Segui questo link per vedere altri tipi di pubblicazioni sul tema: Produced waters.
Tesi sul tema "Produced waters"
Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili
Vedi i top-50 saggi (tesi di laurea o di dottorato) per l'attività di ricerca sul tema "Produced waters".
Accanto a ogni fonte nell'elenco di riferimenti c'è un pulsante "Aggiungi alla bibliografia". Premilo e genereremo automaticamente la citazione bibliografica dell'opera scelta nello stile citazionale di cui hai bisogno: APA, MLA, Harvard, Chicago, Vancouver ecc.
Puoi anche scaricare il testo completo della pubblicazione scientifica nel formato .pdf e leggere online l'abstract (il sommario) dell'opera se è presente nei metadati.
Vedi le tesi di molte aree scientifiche e compila una bibliografia corretta.
1
Multon, Lance Michael. "Removal of oil from produced waters". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ60239.pdf.
Testo completo
2
Jackson, Richard E. "Geochemistry of coalbed natural gas produced waters in the Powder River Basin, Wyoming". Laramie, Wyo. : University of Wyoming, 2009. http://proquest.umi.com/pqdweb?did=1799840421&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
Testo completo
3
Tohidikaloorazy, Foroogh. "Fundamental controls on kinetic hydrate inhibitor performance and polymer removal from produced waters". Thesis, Heriot-Watt University, 2016. http://hdl.handle.net/10399/3235.
Testo completoAbstract (sommario):
Gas hydrate formation is one of the major concerns in the oil and gas industry, posing considerable risks to production operation when it is not controlled. Gas hydrates are traditionally avoided by injecting thermodynamic inhibitors (THIs) such as methanol or MEG, however over the past two decades, in response to economic and HS&E concerns associated with THIs, low dosage “Kinetic Hydrate Inhibitors” (KHIs) have seen increasing use in the industry as an alternative. Although KHIs use is now quite widespread and can offer considerable CAPEX/OPEX benefits, their hydrate inhibition mechanisms are still relatively poorly understood. In this thesis, a novel PVT phase behaviour/ crystal growth inhibition (CGI) method previously developed in-house has been used to study fundamental controls on KHI inhibition mechanisms in terms of gas and aqueous phase composition, pressure, polymer type and presence of other pipeline chemicals. Particular focus has been placed on gas composition, notably acid/sour gases, with results strongly suggesting that cage occupancy patterns play a crucial role in KHI inhibition performance as a function of pressure and presence of CO2 and H2S being a significant factor. In contrast, work on the effect of pH does not suggest pH reduction to be the main contributor to the observed behaviour in system containing CO2/H2S. In addition, extensive studies on KHI-THI mixtures for different KHI polymers in multi-component natural gas systems have revealed a potential synergistic effect of methanol up to a certain concentration, while proving a consistent ‘top-up’ effect for ethylene glycol, opening up options for novel combined KHI-THI inhibition strategies. While KHIs are gaining particular interest, there is the issue of handling/disposal of produced waters with the potential of polymer fouling problems. To address this problem, robust evaluation of a recently developed solvent extraction based polymer removal method shows this to have significant promise. Results also suggest that presence of other pipeline chemicals will not affect the removal effectiveness significantly. Work has also been expanded to examine whether the treatment chemicals themselves might offer a novel means to create “water immiscible KHIs” for certain applications. Results indicate that such a KHI formulation can work well, even though the bulk of the polymer is not in the aqueous phase but in an immiscible organic chemical. The treatment chemical extraction method also opens up options for potential KHI recovery and re-use.
4
Furrow, Brendan Eugene. "Analysis of hydrocarbon removal methods for the management of oilfield brines and produced waters". Texas A&M University, 2005. http://hdl.handle.net/1969.1/2611.
Testo completoAbstract (sommario):
According to the Texas Railroad Commission (TRC), ????over 250 billion gallons
of produced water is taken out of Texas Soil every year, and more than 35% of this
water is not currently fit to use.?? Therefore, it can be assumed that domestically and
globally, the petroleum industries challenge has been to develop a high-tech and cost
effective method to purify the large volumes of oilfield brines and produced water.
Currently, most of the produced water requires several pre- and post- treatment methods
to aide in reducing fouling of membranes, separation of components, increasing influent
and effluent quality, and preventing unwanted work stoppage during the desalination
process. As a result, the pre- and post- treatment conditioning of the produced water
affects the economics and scale-up (i.e. residence times, absorption capacity, etc??) of
the varying processes parameters. Therefore, this research focuses on developing an
economic analysis and determining the adsorption capacity of an organoclay system to
remove oil.
5
Johnson, Brenda Marie. "Remediation of risks in natural gas storage produced waters the potential use of constructed wetland treatment systems /". Connect to this title online, 2006. http://etd.lib.clemson.edu/documents/1171041556/.
Testo completo
6
Dong, Xiao. "Techno-Economic Analysis of a Cost-Effective Treatment of Flowback and Produced Waters via an Integrated Precipitative Supercritical Process". Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1429533649.
Testo completo
7
King, Lyle A. "Land application with saline-sodic coalbed natural gas co-produced waters in Wyoming's Powder River Basin impacts to soil and biological properties /". Laramie, Wyo. : University of Wyoming, 2006. http://proquest.umi.com/pqdweb?did=1221694361&sid=3&Fmt=2&clientId=18949&RQT=309&VName=PQD.
Testo completo
8
BARBOSA, Tellys Lins Almeida. "Desempenho e validação de um sistema com automação para processos de separação água/óleo com membranas cerâmicas". Universidade Federal de Campina Grande, 2014. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/531.
Testo completoAbstract (sommario):
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-30T17:51:31Z
No. of bitstreams: 1
TELLYS LINS DE ALMEIDA BARBOSA - DISSERTAÇÃO PPGEQ 2014..pdf: 2340446 bytes, checksum: 3a2ea16e16c4359a82b431379410d16c (MD5)Made available in DSpace on 2018-04-30T17:51:31Z (GMT). No. of bitstreams: 1 TELLYS LINS DE ALMEIDA BARBOSA - DISSERTAÇÃO PPGEQ 2014..pdf: 2340446 bytes, checksum: 3a2ea16e16c4359a82b431379410d16c (MD5) Previous issue date: 2014-09-26
O presente trabalho visa estudar o desempenho e validação de um sistema com automação para processos de separação de águas oleosas com membranas cerâmicas. O trabalho foi dividido em duas partes: testes em escala de bancada e no sistema com automação. Nos ensaios em escala de bancada foram realizados experimentos de caracterização da membrana cerâmica com água deionizada e com efluente sintético, com intuito de estimar o comportamento das membranas para auxiliar no desenvolvimento do sistema com automação. Para avaliar o desempenho dos sistemas de separação água/óleo com membranas cerâmicas os seguintes parâmetros foram analisados: fluxo do permeado (J, em L/h.m2) e taxa de rejeição de óleo. Nos experimentos no sistema com automação foi avaliado o desempenho no processo de separação água/óleo com membranas cerâmicas, o efluente sintético utilizado obedeceu às mesmas condições do sistema de bancada. Os experimentos com efluente sintético foram simulados com concentração de óleo fixada em 20 mg/L. Observou-se que a redução do fluxo de permeado com o tempo de operação é fortemente dependente da pressão e do teor de óleo emulsionado, podendo ser relacionada aos fenômenos de polarização por concentração, inerentes aos PSM. Contudo, a redução do fluxo no permeado foi atenuada no sistema com automação que possui processos de limpeza backpulse e backwash. Quanto à taxa de rejeição da fase dispersa, para todas as condições analisadas, apresentou-se maior que 97%. A utilização do backwash tendo como agente de limpeza uma solução de hidróxido de sódio não foi eficaz na recuperação do fluxo do permeado, porém o comportamento do processo de limpeza foi extremamente satisfatório o que indica com a mudança do agente de limpeza no processo terá uma melhor recuperação do fluxo do permeado. A partir dos experimentos realizados no sistema com automação os resultados obtidos demostram potencial para separação com membranas cerâmica, para o tratamento de águas oleosas.
This work aims to study the performance and validation of system with automation to oily water separation processes with ceramic membranes. It was divided into two phases: laboratory-scale tests and tests with the system with automation. In the laboratory-scale tests, experiments to characterize the ceramic membrane were carried out with deionized water and synthetic effluent, aiming to estimate the behavior of membranes to assist the developing of the system with automation. To evaluate the performance of the water-oil separation systems with ceramic membranes the following parameters were analyzed: permeate flow (J, L/h.m2) and oil rejection rate. In the experiments with the automatic system the performance was evaluated in oil-water separating process with ceramic membrane, the synthetic effluent used followed the same conditions as the benchtop system. The experiments with synthetic effluent were simulated with oil concentration set at 20 mg/L. It was observed that the reduction of the permeate flux with the operation time is strongly dependent of the pressure and emulsified oil content, may be related to concentration polarization, inherent to membrane separation processes. However, the reduction of permeate flow was attenuated in the system with automation where backpulse and blackwash cleaning processes were used. The dispersed phase rejection rate, for all conditions analyzed, was greater than 97%. The backwash cleaning system having sodium hydroxide as cleaning agent was not effective to increase the permeate flow, but the cleaning agent performance was extremely satisfactory which indicates that the change of the cleaning agent in the process will increase the flow in the permeate stream. From the experiments carried out with the system with automation results demonstrate the potential for separation with ceramic membranes, for oily water treatment.
9
Furno, Laetitia. "Etude et caractérisation d’additifs anticorrosion utilisés dans l’industrie pétrolière par chromatographie en phase liquide à ultra haute performance et spectrométrie de masse haute résolution". Electronic Thesis or Diss., Université Paris sciences et lettres, 2024. http://www.theses.fr/2024UPSLS028.
Testo completoAbstract (sommario):
Les additifs sont des mélanges complexes de substances chimiques utilisés en petite quantité pour améliorer la production, ou prévenir des problèmes (corrosion des infrastructures, formation d’émulsions, dépôts de cire, etc.). Ces produits sont mal connus des industriels qui les utilisent car les compositions sont gardées secrètes par les fournisseurs, et les méthodes de suivi usuellement employées sont peu sensibles et souvent non spécifiques. L’objectif de la thèse est d’améliorer la connaissance de l’une de ces familles d’additifs, les inhibiteurs de corrosion, et de développer une approche UHPLC-HRMS permettant leur analyse dans des eaux de production.Dans un premier temps, une méthode UHPLC-HRMS a été développée. Un criblage de colonnes a été mené sur 8 colonnes de chromatographie en phase inverse, afin de trouver celle qui permettrait la meilleure séparation de molécules modèles représentatives de celles retrouvées dans les additifs commerciaux. Pour réaliser cette comparaison multicritère, les fonctions de désirabilité de Derringer ont été utilisées. Dans un second temps, trois additifs commerciaux ont été analysés en HRMS (Orbitrap) et en spectrométrie de masse en tandem. La haute résolution, ainsi que l’étude des mécanismes de fragmentation des ions, ont permis l’élucidation des structures des molécules majoritairement présentes dans les mélanges commerciaux. Ensuite, la méthode UHPLC-HRMS développée a été appliquée pour l’analyse des inhibiteurs de corrosion précédemment étudiés, dans de l’eau pure et dans des eaux de production. Enfin, il a été observé que ces additifs peuvent s’adsorber sur de nombreuses surfaces, incluant le verre des flacons utilisés pour l’injection en chromatographie. La méthode développée a donc été mise en œuvre pour mieux comprendre les phénomènes d’adsorption des inhibiteurs de corrosion à l’aide notamment de plans d’expériences, et ainsi mieux maitriser leur quantificationAdditives are blends of chemicals used in small quantities to improve production or prevent issues (infrastructure corrosion, emulsion formation, wax deposits, etc.). These products are not well understood by the end user because their composition is kept secret by suppliers, and the monitoring methods typically employed are not very sensitive and often non-specific. The objective of the thesis is to improve the understanding of one of these families of additives, the corrosion inhibitors, and to develop a UHPLC-HRMS method for their analysis in produced waters.Firstly, a UHPLC-HRMS method was developed. A column screening was conducted on 8 reverse-phase chromatography columns to find the one that would allow the best separation of model molecules representative of those found in commercial additives. To perform this multi-criteria comparison, Derringer’s desirability functions were used. Secondly, three commercial additives were analyzed using HRMS (Orbitrap) and tandem mass spectrometry. The high resolution, as well as the study of ion fragmentation mechanisms, allowed the elucidation of the structures of the molecules predominantly present in the commercial mixtures. Then, the developed UHPLC-HRMS method was applied to the analysis of the commercial corrosion inhibitors previously studied, in pure water and in produced waters. Finally, it has been observed that these additives can adsorb onto various surfaces, including the glass of the vials used for injection in chromatography. The developed method was therefore implemented to better understand the adsorption phenomena of corrosion inhibitors, using experimental designs, and thus better control their quantification
10
Sousa, Magna Ang?lica dos Santos Bezerra. "Desenvolvimento de um destilador solar para tratamento de ?guas de produ??o de petr?leo com vistas a sua utiliza??o na agricultura e gera??o de vapor". Universidade Federal do Rio Grande do Norte, 2004. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15754.
Testo completoAbstract (sommario):
Made available in DSpace on 2014-12-17T15:01:15Z (GMT). No. of bitstreams: 1
MagnaASB.pdf: 1635517 bytes, checksum: df420c88397a6cd630a5381fcef348b7 (MD5)
Previous issue date: 2004-09-02The production of petroleum is frequently accomplished with great volumes of water, that it is carried of the underground with the oil. It is a challenge of the present century the development of technologies that allow the use of waste water for purposes that consume great amounts of water and don't demand as rigid as the one of the drinking water requirements. The solar distillation has been configuring as an alternative of clean technology for desalination of brine and saline. Besides causing the minimum possible damage to the environment, it takes advantage of an abundant and free energy source: the solar energy. That study aims to develop a Solar Distillator for treatment of the produced water of the oil wells, to obtain an efluent to use in agriculture and vapor generation. The methodology for collection, conservation and analysis of the physical-chemical parameters obeyed the norms in APHA (1995). The sampling was of the composed type. Experiments were accomplished in the solar distillation pilot and simulation in thermostatic bathing. The operation was in batch system and for periods of 4, 6 and 12 h. The developed Distillator is of the type simple effect of two waters. It was still tested two inclination angles for covering; 20? and 45?. The Distillator presented minimum of 2,85 L/m2d revenues and maximum of 7,14 L/m2d. The removals of salts were great than 98%. The removal of TOC in the simulation was great than 90%. In agreement with the data of energy and mass balance, it was verified that the developed solar Distillator presented compatible revenues with those found in literature for similar types. It can be inferred that the obtained distilled water assists to the requirements CONAMA in almost all the points and could be used for irrigation of cultures such as cotton and mamona. As the distilled water has characteristics of fresh water it can be used in the generation of vapor
A produ??o de petr?leo ? realizada freq?entemente com grandes volumes de ?gua, que ? carreada do subsolo junto com o ?leo. ? desafio do presente s?culo o desenvolvimento de tecnologias que possibilitem ou uso ou reuso de efluentes para outros fins. A destila??o solar ? uma alternativa de tecnologia limpa para dessaliniza??o de ?guas salobras e salinas. Esse estudo visa desenvolver um Destilador Solar para tratamento da ?gua de produ??o de petr?leo, com vistas a se obter um efluente pass?vel de utiliza??o na agricultura e gera??o de vapor. A metodologia para conserva??o e an?lise dos par?metros f?sico-qu?micos obedeceu preconiza??o do APHA (1995). A amostragem foi do tipo composta. Foram realizados experimentos no destilador solar piloto e simula??o em banho termost?tico. A opera??o foi em sistema de batelada e por per?odos de 4, 6 e 12 h. O destilador desenvolvido ? do tipo simples efeito de duas ?guas. Testou-se ainda dois ?ngulos de inclina??o para cobertura; 20? e 45?. O destilador apresentou rendimentos m?nimo de 2,50 L/m2d e m?ximo de 7,5 L/m2d. As remo??es de sais foram superiores a 98%. A remo??o de TOC na simula??o foi superior a 90%. De acordo com os dados dos balan?os energ?tico e de massa, verificou-se que o destilador solar desenvolvido apresentou rendimentos compat?veis com os encontrados na literatura para seus similares. Enfatiza-se que o isolamento utilizado n?o estava nas condi??es de otimiza??o, logo, esse rendimento pode ser melhorado. Pode-se inferir que a ?gua destilada obtida atende aos requisitos CONAMA em quase todos os pontos, podendo ser utilizada, com ressalvas, na irriga??o de culturas n?o comest?veis como o algod?o e a mamona. Como a ?gua destilada tem caracter?sticas de ?gua doce pode ser utilizada na gera??o de vapor
11
Sprague, Nicolle Marie. "Copper in the Urban Water Cycle: Sources and Sinks, Benefits and Detriments, and Corrosion in Soft Waters". Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/42724.
Testo completoAbstract (sommario):
In recent years, stringent world-wide regulation of copper in drinking water, wastewater discharge and sludge has prompted utilities to carefully evaluate copper sources and sinks, benefits and detriments, and mitigation. This work compiled the individual efforts of researchers and utilities to provide a basis for holistic decision-making. Mass balances suggest that between 14-61% of copper in wastewater originates from home plumbing. Dosing of pure copper sulfate "root killer" by consumers, which is of unlikely value, accounted for up to 27% of copper inputs. Removal of copper in wastewater treatment ranged from 24-90%, suggesting a potential for optimization of these processes if desired. Finally, though utilities are pressured to reduce copper inputs at all stages of the urban water cycle, substantial benefits including human and wastewater bacteria micro-nutrition, water disinfection and algae control should not be overshadowed.
To better understand copper inputs from corrosion in soft waters, a 12 month study was executed. Free chlorine (0.7 mg/L) was determined to have minimally adverse effects on copper release at pH 9.5 but no significant effect at pH 7.0, and higher temperatures usually increased copper release. Organic matter including soluble and particulate NOM, sodium alginate, and gum xanthan, tended to worsen copper release. Their direct effects included complexation and mobilization of pre-existing copper scale as particulates. Indirect effects were also discovered, including a propensity of gum xanthan and alginate to decrease pH, increasing copper release, and also to produce a microbiologically unstable water, decreasing the dissolved oxygen necessary for fueling corrosion reactions. The range of organic matter effects could be placed within a unified conceptual framework.Master of Science
12
Patel, Chirag V. "Management of produced water in oil and gas operations". Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/1544.
Testo completoAbstract (sommario):
Produced water handling has been an issue of concern for oil and gas producers as it is one of the major factors that cause abandonment of the producing well. The development of effective produced water management strategies poses a big challenge to the oil and gas industry today. The conversion of produced water into irrigation or fresh water provides a cost effective tool to handle excessive amounts of the produced water. In this research we proposed on-site produced water treatment units configured to achieve maximum processing throughput. We studied various advanced separation techniques to remove oil and dissolved solids from the produced water. We selected adsorption as the oil removing technique and Reverse Osmosis (RO) as the dissolved solids removing technique as being the best for our purpose. We performed experiments to evaluate operating parameters for both adsorption and RO units to accomplish maximum removal of oil and dissolved solids from the produced water. We compared the best models fitting the experimental data for both the processes, then analyzed and simulated the performance of integrated produced water treatment which involves adsorption columns and RO units. The experimental results show that the adsorption columns remove more than 90% of the oil and RO units remove more than 95% of total dissolved solids from the produced water. The simulation results show that the proper integration and configuration of adsorption and RO units can provide up to 80% efficiency for a processing throughput of 6-8 gallons per minute of produced water. From an oil and gas producers viewpoint output from the produced water treatment system is a revenue generating source. The system is flexible and can be modified for the applications such as rangeland restoration, reservoir recharge and agricultural use.
13
Brookes, Adam. "Immersed membrane bioreactors for produced water treatment". Thesis, Cranfield University, 2005. http://dspace.lib.cranfield.ac.uk/handle/1826/4508.
Testo completoAbstract (sommario):
The performance of a submerged membrane bioreactor for the duty of gas field produced water treatment was appraised. The system was operated under steady state conditions at a range of mixed liquor suspended solids (MLSS) concentrations and treatment and membrane performance examined. Organics removal (COD and TOC) display removal rates between 90 and 97%. Removal of specific target compounds Benzene, Toulene, Ethylbenzene and Xylene were removed to above 99% in liquid phase with loss to atmosphere between 0.3 and 1%. Comparison of fouling rates at a number of imposed fluxes has been made between long term filtration trials and short term tests using the flux step method. Produced water fed biomass displays a greater fouling propensity than municipal wastewater fed biomass from previous studies. Results indicate an exponential relationship between fouling rate and flux for both long and short term trials, although the value was an order of magnitude lower during long term tests. Moreover, operation during long term trials is characterised by a period of pseudo stable operation followed by a catastrophic rise in TMP at a given critical filtration time (tfi, ) during trials at 6 g. L"1. This time of stable operation, tfit, is characterised by a linear relationship between fouling rate and flux. Results have been compared with the literature. Data for membrane fouling prior to the end of t fit yielded a poor fit with a recently proposed model. Trends recorded at t> trlt revealed the fouling rate to follow no definable trend with flux. The system showed resilience to free oil shocking up to an oil concentration of 200ppmv. Following an increase in oil concentration to 500 ppmv, rapid and exponential fouling ensued.
14
Foslie, Sverre Stefanussen. "Design of Centrifugal Pump for Produced Water". Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-24348.
Testo completoAbstract (sommario):
During the spring of 2008, Jón Bergmann Heimisson developed a pump design program in Matlab. The program has been further developed during the work with this thesis, as well as in the author's preceding project thesis, giving key information for an existing pump design. The aim of this Master's thesis has been to verify the calculation of pump characteristics and velocity profiles at the impeller outlet through testing.A detailed description of the relevant theory regarding pump design has been presented, and different calculation models for the pump characteristics have been examined. The analytical approaches for calculating the performance data have been implemented into Matlab, and a comparison of the different calculation models has been performed. A multistage centrifugal pump has been used for verifying the velocity profiles, and the pump characteristics have been compared to the different calculation models presented in Matlab. Measurements of the velocity profiles were carried out in Typhonix' laboratories at Varhaug using a pitot-static probe.The results achieved from the comparison of the characteristic curves calculated in Matlab showed that the models provide quite different results. Some of the methods widely used in the literature proved to deviate significantly from the measured results, while other and more advanced methods provided better results.The results achieved from testing the velocity profiles with the pitot-static probe were not as good as desired. The measured velocities and flow angles did not correlate well with the analytical solutions, and the results are partly unreliable. Some of the trends regarding changes due to increased volume flow or rotational speed were found, but the exact values could not be trusted. The pitot-static probe is an intrusive method, and it probably disturbed the flow in a way making good results difficult to achieve.
15
Shpiner, R. A. M. "Treatment of produced water by waste stabilsation pond". Thesis, Imperial College London, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498655.
Testo completo
16
Alanezi, Yousef H. "Crossflow microfiltration of oil from synthetic produced water". Thesis, Loughborough University, 2009. https://dspace.lboro.ac.uk/2134/8815.
Testo completoAbstract (sommario):
Produced water is formed in underground formations and brought up to the surface along with crude oil during production. It is by far the largest volume byproduct or waste stream. The most popular preference to deal with produced water is to re-inject it back into the formation. Produced water re-injection (PWRI) needs a treatment before injection to prevent formation blockage. Due to the increase of produced water during oil production in the west of Kuwait, an effluent treatment and water injection plants were established and commissioned in 2004 so that produced water could be used for re-injection purposes. It is estimated that oil wells in the west of Kuwait produce 15 to 40 % of produced water. The main aim of this treatment train is to reduce not only the oil-in-water amount to less than 10 ppm, but also total suspended solids to 5 ppm which is the maximum allowable concentration for re-injection and disposal. Furthermore, with respect to the upper limit for injection, the maximum number of particles between 5 and 8 microns is 200 in 0.1 ml. In practice the number is found to exceed this limit by 10 times...
17
Khor, Ee Huey. "Improvements of oil-in-water analysis for produced water using membrane filtration". Thesis, Curtin University, 2011. http://hdl.handle.net/20.500.11937/2563.
Testo completoAbstract (sommario):
The accuracy of oil-in-water analysis for produced water is increasingly crucial as the regulations for disposal of this water are getting more stringent world wide. Currently, most of the oil producing countries has their own regulations for disposal of this water. The oil-in-water can be distinguished between two types, mainly dispersed and dissolved oil. Among these oils, dispersed oil concentration is the main component under monitoring for the oil-in-water limitation. From literatures, the standard analytical method for oil-in-water measurement has been changed from IR analysis to GC-FID analysis due to solvent restrictions. As a result of the change, a total of dispersed and dissolved oil is measured and this causes the oil-in-water parameter value to be higher. Therefore the removal of dissolved oil before oil-in-water analysis is critical. This issue can be overcome by enhancing current monitoring technique which incorporates a separation technique in removing dissolved oil from the produced water prior to the GC-FID analysis.A thorough review was given to all current available separation techniques that can be employed for dissolved oil removal. Membrane filtration system was proposed in this research to be incorporated into the test method to remove the dissolved oil as it is relatively a small separation unit, easy to operate and very practical in the laboratory scale application. By using membrane filtration, it was found that the removal of dissolved oil is dependent on the pore-size of the membrane where in this case Microfiltration removes more dissolved oil than Ultrafiltration.However, there is an issue in using this membrane filtration technique. The deposition of dispersed and dissolved oil on the membrane reduces the efficiency of the removal process. In this research, mathematical & computational modelling was done in studying the hydrodynamic effect caused by pressure for the fluid flow profile inside the membrane cartridge. Then, two approaches are proposed prevention of fouling, firstly, by physical or mechanical means and secondly, by chemical means. The use of mechanical means for the prevention of deposition were studied by simulation using computational fluid dynamics (CFD) and mathematical model to visualize the hydrodynamic conditions inside the membrane cartridge.Mathematical model has been developed for the relationship of differential pressure(DP) with the concentration of oils at the wall (Cg). The purpose of this study is toestimate the concentration of oils by changing the differential pressure. Severalfactors for the reduction of fouling or the concentration of oils at the membrane wallby physical means such as pore sizes, membrane types and operating conditions werestudied. The experimental data were analyzed by using statistical method. Throughdesign of experiment (DOE) and the verification of CFD visualization, the optimumconditions for the operation were identified to be at low differential pressure (DP)but at high trans-membrane pressure (TMP). The most suitable type of membranewith 0.2um pore size was found to give highest efficiency in removing dissolved oil.Despite these findings, the total prevention of oil fouling on the membrane by mechanical means is not possible. Therefore, chemical pre-treatment method and chemical cleaning methods were explored in their capacity to remove the deposition of oil on the membrane. This pre-treatment method enhances the separation by changing the physical properties of the oil towards the membranes. Changes of chemical properties of oil should be avoided in this attempt for accuracy of measurement. pH changes are one of the ways for pre-treatment, and the effects of acidity and alkalinity effect on the solution were studied for the improvement of the separation.Chemical cleaning using NaOH was investigated for its ability to clean off the deposition of oils on the membrane. The duration of the cleaning as well as the volume used were studied experimentally until the optimum conditions were reached. The chemical treatment approaches are integrated into the physical method to enhance the removal of dissolved oil by using membrane filtration. The optimum condition of this integrated techniques were verified experimentally.In conclusion a new standard analysis method in the oil-in-water parameter monitoring for produced water in the oil and gas sector has been developed. With the incorporation of membrane filtration system, produced water analysis will be improved, which would benefit the oil and gas operators.
18
Laurenson, Chevonne Hazel. "Aspects of the biology and fishery for monkfish Lophius piscatorius Linnaeus 1758 in waters around the Shetland Isles, Northeastern Atlantic". Thesis, University of Aberdeen, 2003. http://www.ices.dk/products/CMdocs/2001/J/J2701.pdf.
Testo completo
19
Shrawage, Abhijeet J. "CFD Analysis of Supercritical Water Reactor for Flow Back and Produced Water Treatment". Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1407229655.
Testo completo
20
Hong, Soklida. "Glutaraldehyde Removal from Produced Water Using Photolysis and Photocatalysis". Thesis, North Dakota State University, 2017. https://hdl.handle.net/10365/28665.
Testo completoAbstract (sommario):
Glutaraldehyde (GA) has been used extensively as a biocide in hydraulic fracturing fluids leading to the contamination of the compound in produced water. In this study, the performances of photolysis and photocatalysis for removal of GA in synthetic produced water were investigated. The photolytic degradation rate of GA increased with increasing incident ultraviolet light intensity and decreasing pH. Increasing initial GA concentration resulted in a reduced rate of GA degradation. At high salt concentrations, similar to the levels found in produced water, the photodegradation rate of GA was better than those at zero/low salt concentrations. In photocatalytic experiments, GA could be degraded efficiently under both simulated visible light and natural sunlight. Photolysis and photocatalysis are promising technologies for removing GA in produced water due to their small footprint, ease of operation, and efficiency. This study helps in addressing an obstacle associated with produced water treatment and disposal.North Dakota Water Resources Research Institute Fellowship Program
21
Pedrouzo, Lanuza Marta. "Pharmaceuticals and personal care products in environmental waters". Doctoral thesis, Universitat Rovira i Virgili, 2010. http://hdl.handle.net/10803/9058.
Testo completoAbstract (sommario):
En la presente Tesis Doctoral se han desarrollado diferentes métodos analíticos para la determinación de pharmaceuticals and personal care products (PPCPs) en aguas medioambientales. El término PPCPs engloba todos los fármacos, drogas de abuso, hormonas y los excipientes activos incluidos en productos de uso personal, así como los metabolitos, conjugados y sub-productos de transformación. Los métodos desarrollados han estado basados en extracción en fase sólida o extracción con barras magnéticas agitadoras seguidos de la cromatografía líquida acoplada a la espectrometría de masas o de masas en tándem. Debido a los bajos límites de detección alcanzados, estos métodos se pudieron aplicar a la monitorización de estos compuestos en diferentes plantas depuradoras del área de Tarragona, donde la información al respeto era inexistente. Debido a que el principal destino de las aguas residuales son los ríos, se analizaron aguas del Ter, Llobregat y Ebro. Para completar el estudio, la presencia de PPCPs fue determinada en aguas de consumo.In the framework of the present Doctoral Thesis different analytical methods have been developed to determine pharmaceuticals and personal care products (PPCPs) in environmental waters. The term PPCPs cover all the pharmaceuticals, drugs of abuse, hormones, the active compounds included in personal care products, and also metabolites, conjugates and transformation sub-products. The developed methods were based on solid-phase extraction and stir bar sorptive extraction followed by liquid chromatography coupled to mass spectrometry and tandem mass spectrometry. Achieving the low limits of detection, these methods could be applied to the monitoring of these compounds in different sewage treatment plants from Tarragona Region, where not data were available. The PPCPs resulting in the effluent sewage waters can achieve rivers. Therefore, waters from three rivers: Ter, Llobregat and Ebro were analyzed. To complete the study, also drinking water was analyzed to determine PPCPs.
22
Lee, Yang Bong. "Effect of water activity on headspace volatile compounds produced in whey protein concentrate and other spray dried dairy products during accelerated storage /". The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487843688959376.
Testo completo
23
Greyshock, Aimee E. "Evaluation of Triclosan Reactivity in Monochloraminated Waters". Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/36295.
Testo completoAbstract (sommario):
The antibacterial agent, triclosan, is widely used in many household personal care products, and it has recently been detected in wastewater treatment plant effluents and in source waters used for drinking water supply. Accordingly, the reactivity of triclosan with the disinfectants used in wastewater treatment and in the production of potable water is of interest. Monochloramine is used as an alternative disinfectant in drinking water treatment to minimize production of regulated disinfection by-products. This study examined the reactions between triclosan and monochloramine and involved analysis of monochloramine and triclosan decay and product formation under drinking water treatment conditions over a pH range of 6.5 to 10.5. Monochloramine decay in the presence of triclosan was measured relative to monochloramine auto-decomposition in the absence of triclosan using UV-VIS spectrophotometry. Experimental results showed that the monochloramine auto-decomposition intermediates, free chlorine and dichloramine, are responsible for a majority of the observed triclosan decay and product formation. A kinetic model for monochloramine auto-decomposition was modified to include terms and rate coefficients for the reactions of triclosan with monochloramine (k = 90.4 M-1h-1), free chlorine (k = 1.94×107 M-1h-1), and dichloramine (k = 2×105 M-1h-1), and was able to predict triclosan and monochloramine decay. It was determined that the reactions of dichloramine and free chlorine with triclosan were 103 and 105 times faster, respectively, than the reaction of monochloramine with triclosan. The products of these reactions, detected using GC-MS, included three chlorinated triclosan intermediates, 2,4-dichlorophenol, and 2,4,6-trichlorophenol. Low levels of chloroform were detected at pH values of 6.5 and 7.5.Master of Science
24
Lin, Jack. "Pre-treatment of coal seam water with coagulation and electrocoagulation". Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/105358/4/Jack_Lin_Thesis.pdf.
Testo completoAbstract (sommario):
This thesis examined innovative methods for pre-treatment of coal seam water. In order to prevent scaling and fouling of downstream reverse osmosis membranes we investigated both electrocoagulation and chemical coagulation using aluminium and iron based electrodes and/or coagulants. Application of electrocoagulation was found to significantly reduce the presence of problematic dissolved species such as silica and also alkaline earth ions which potentially can scale membranes and equipment. Chemical coagulation could also remove dissolved silica from simulated coal seam water samples but was found to be relatively ineffective when treating real coal seam water. The future study of electrocoagulation is worthy in order to determine its applicability to a wider range of coal seam water compositions and to minimise costs of use.
25
Brassill, Natalie A. "The Assessment of Escherichia coli as an Indicator of Microbial Quality of Irrigation Waters used for Produce". Thesis, The University of Arizona, 2013. http://hdl.handle.net/10150/293596.
Testo completoAbstract (sommario):
Escherichia coli is a bacterial species that lives in the gut of all warm-blooded animals, fish, birds as well as reptiles and is commonly used as an indicator of fecal contamination in water. This project assessed currently used culture based media for the detection of E. coli in irrigation waters used in Arizona and California, and will present recommendations towards the most reliable media for the evaluation of irrigation waters used for produce. Currently, no microbial indicator standards exist for irrigation waters used for produce production in the United States. The produce industry suggests that the recreational water standard guideline (126 E. coli/100 ml) established by the United States Environmental Protection Agency (USEPA) be used. There is concern that the false positive rate of E. coli detection may be high in these waters giving false indications of the level of risk from enteric pathogens. This project evaluated three commercially available media for E. coli detection to test irrigation waters from three agricultural areas (Yuma and Maricopa, AZ and Imperial Valley, CA) and then assessed false positive rates by utilizing Polymerase Chain Reaction (PCR) and DNA sequencing of the bacterial isolates. The media that were chosen for evaluation were (1) MI Agar, (2) IDEXX Colilert Quanti-Tray® and (3) m-ColiBlue24® broth, all evaluation media accepted by the USEPA and widely used in the monitoring of irrigation water quality by the produce industry. Four hundred and fifty 1-L irrigation water grab samples were collected between March 2012 and November 2012. The samples were analyzed for both cultural counts and water quality parameters including temperature, salinity and pH. Isolates positive and negative for E. coli were then selected and assessed utilizing PCR and DNA sequencing. The false positive rate of each method was found to be high, with MI Agar, m-ColiBlue24® broth and the IDEXX Colilert Quanti-Tray® at an accuracy of 67%, 72%, and 51% respectively. A false positive result is reported when presumptive E. coli sub cultured from the media is found to be non-E. coli through molecular analysis. Overall the IDEXX Colilert Quanti-Tray® performed at a greater rate of accuracy than the other two media evaluated, however, high false positive rates may lead to inaccurate assessment of water quality.
26
Palsson, Bjarni. "A study on the parameters controlling (matrix) injectivity of produced water". Thesis, Heriot-Watt University, 2004. http://hdl.handle.net/10399/2021.
Testo completoAbstract (sommario):
There is a lack of general design methods for water injection schemes. This is reflected in the fact that there exists no handbook for water injection and no commercial reservoir simulators include modules for injectivity damage; even though waterflood simulation is one of their main tasks. This thesis aims at critically evaluating the current approach and suggesting better practises. The objective is to analyse the parameters affecting the performance of matrix water injection wells and critically evaluate their importance in the light of available field history. This includes a review of the injectivity damage mechanisms involved and evaluation of the prediction methods available to quantifY their reliability for real field cases. The following steps are presented: » Review of current understanding of water injection performance. ? » Review of published coreflood experiments with the aim of identifYing both main trends and the key differences. Other potential damage mechanisms are also discussed briefly. » Available injectivity prediction models are evaluated for sensitivities in the input parameters and compared against both core experiments and field performance. » Field information from more than I00 wells, operated by 15 international oil companies was acquired. The information is critically analysed in consistent manner and the main trends identified and compared to the key findings ofthe laboratory and model approaches. The field data proved generally insufficient to provide a firm correlation relating water quality and formation characteristics to injectivity decline. This comparative investigation does however, indicate the uncertainty range in the key parameters involved and does, therefore, result in an improved understanding of the injectivity mechanisms. The key findings are summarised in brief guidelines for best operational practices for water injection. Furthermore, areas of significant inconsistencies, requiring further investigation, are identified and recommendations made as a basis of research activity to fill some of the many gaps in understanding in this important topic.
27
Donnelly, Alan Paul. "On-line concentration measurement and separation of oil from produced water". Thesis, Heriot-Watt University, 2001. http://hdl.handle.net/10399/506.
Testo completo
28
FALLER, MARIA CLARA KREMER. "ASPECTS OF THE UTILIZATION OF HUMIC SUBSTANCE IN PRODUCED WATER TREATMENT". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2006. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=9241@1.
Testo completoAbstract (sommario):
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORÁgua de produção consiste de uma das principais preocupações ambientais relacionadas à produção de petróleo. Substâncias húmicas (SH) são naturalmente formadas durante a humificação de matéria orgânica por microorganismos, apresentando uma série de propriedades, dentre essas, a de captura de grande parte dos íons metálicos. O presente trabalho teve com o objetivo principal avaliar a viabilidade da utilização de SH no tratamento da água de produção, considerando a utilização de três diferentes compostos húmicos (HMC). Em relação ao tempo para a completa coagulação/floculação, observou-se uma variação em função da concentração utilizada, para todos os três casos de HMC. HMC-3 apresentou os menores intervalos de tempo, além de interface bem definida e sobrenadante final de aspecto límpido. Os resultados do teor de bário, após adição das HMC, mostram a redução do valor inicial em todos os casos, sendo que a maior redução para 4mL do HMC- 1. Ensaios realizados com as algas detectaram tanto um aumento da clorofila quanto das áreas médias das algas na presença de água de produção, sendo este mais acentuado quando também da presença de HMC-3. Os resultados mostraram ser factível o uso de substâncias húmicas em tratamentos que envolvam uma etapa de cogulação/floculação e confirmam a capacidade das SH de reter espécies metálicas como o bário. Nos ensaios com algas, teve-se forte indicativo da contribuição positiva da presença da água de produção para seu crescimento, especialmente da água de produção com SH. Estes resultados reafirmam o grande potencial do uso das SH em tratamentos ambientais.
Produced water consists in one of the biggest environmental concerns related to oil production activities. Humic Substances (HS) are naturally formed during the humification organic residues by microorganisms and present several properties, amongst them, the ability to bind great part of the metal ions. The present work objectifies the avaluation the viability of the use of HS in the treatment of produced water, consideraing three different humic compounds (HMC-1, 2 e 3). In relation to the time for complete coagulation/floculation, a variation of the times as a function of the concentration of HS was observed, in all three cases. HMC-3 presented the shortest times, well defined interface and supernatant of clear aspect. The results of barium content, after HMC addition, clearly present the reduction of the initial values. The biggest reduction being obtained by 4 mL HMC-1. Tests algae detected an increase in the chlorophyll, as well as in the algae average areas, being this effect was even more accentuated in the presence of HMC-3. The results of the test show the possibility of HS use in treatments which involve a coagulation/floculation step nad confirm the HS capacity to bind metal species such as barium. The tests with algae strongly indicates the positive contribution of the presence of produced water to its growth, especially in the case of the produced water with HS. These results reaffirm the great potential of the use of HS in environmental treatments.
29
Omar, Salem A. S. "Characterisation and bioremediation of soil impacted by Libyan oilfield produced water". Thesis, Sheffield Hallam University, 2013. http://shura.shu.ac.uk/20145/.
Testo completoAbstract (sommario):
A large quantity of produced water (PW) is currently produced during crude oil and natural gas exploration and production. The result and effect of discharging PW on the environment has become a significant issue of environmental concern. PW impacted soil is a common environmental problem associated with oil and gas production. This causes the death of plants and contaminates soil. In addition, impacted soil leads to wide spread contamination of surface waters and shallow aquifers. This work describes an investigation of PW and full characterization of contaminated soils by the disposal of PW at the study site, it includes analysis of both PW and impacted soil using different analytical techniques in order to identify and assay the main constituents that cause the pollution of the soil at the site. The Nasser oilfield, Libya has been chosen as the study site because has a long history of crude oil production since 1956. For this study, six PW samples were collected from the disposal pit bank and through the production stages, eighteen samples of contaminated soil from the disposal pit bank at the study oilfield along with uncontaminated soil samples (taken far from the polluted area) to used as reference. Measurable impacts from PW discharges observed in the soils that have been identified include elevated concentrations of petroleum hydrocarbons and salts in the soil. The total dissolved solids (TDS) concentration in PW and soil can vary between 25407 mg/l to 126065 mg/1, for PW and 20716 mg/kg to 105240 mg/kg for impacted soil. The most common organic contaminants found in-PW are total petroleum hydrocarbon (TPH) and BTEX (benzene, toluene, ethylbenzene and xylenes). The average concentrations of TPH for PW and polluted soil samples ranged from 1.2 mg/1 to 2.9 mg/l for PW and 10550 mg/kg to 90750 mg/kg for soil samples, BTEX were found in PW at the processes stage and the disposal pit. The average BTEX concentration in PW ranged from 0.11 mg/l to 1.86 mg/l. The polyaromatic hydrocarbons (PAHs) and oilfield chemicals (OFCs) (i.e. corrosion inhibitors, scale inhibitors, biocides and demulsifiers) were also detected in soil and PW at the study site. Understanding the composition of PW and the impacted soil are necessary for assessing the possibility of beneficial reuse and to selecting suitable treatment process for PW and soil. The results showed that the main constituents that impact the soil are hydrocarbons and salts.
30
Niu, Jing. "Desalination of Produced Water via Gas Hydrate Formation and Post Treatment". Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/76822.
Testo completoAbstract (sommario):
This study presents a two-step desalination process, in which produced water is cleaned by forming gas hydrate in it and subsequently dewatering the hydrate to remove the residual produced water trapped in between the hydrate crystals. All experiments were performed with pressure in the range of 450 to 800psi and temperature in the range of -1 to 1°C using CO? as guest molecule for the hydrate crystals. The experiments were conducted using artificial produced waters containing different amounts of NaCl, CaCl₂ and MgCl₂ at varying temperature (T) and pressure (P). The results are presented as functions of %Reduction of difference chemical elements, CO? requirements and applied T and P conditions.
The impact of dewatering techniques, including centrifuge and filtration process, on gas hydrate solid product is studied. The results showed that over 99% of dissolved NaCl and MgCl2 can be removed from artificial saline water in laboratory experiments. This was achieved in a process involving a single-stage hydrate formation step, followed by a single-step solid-liquid separation (or dewatering). The results also show that the %Reduction (percentage of the concentration decrease) of artificial produced water increases with centrifugation time and rotational speed (rpm). The %Reduction was increased considerably after hydrate crystals were crushed and filtered, indicating that the artificial process water was entrapped in between the hydrate crystals. It was found also that the finer the particle size, the higher the extent of salt removal. In general, filtration was a better than centrifugation for the removal of TDS (Total Dissolved Solids).Master of Science
31
Ali, Ayman W. "Performance Evaluation of Foamed Warm Mix Asphalt Produced by Water Injection". University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1374518551.
Testo completo
32
Vaziri, Mojgan. "Water Resistance of Scots Pine Joints Produced by Linear Friction Welding". Thesis, Nancy 1, 2011. http://www.theses.fr/2011NAN10059/document.
Testo completoAbstract (sommario):
Le soudage du bois est une technique d'assemblage sans adhésif de deux pièces de bois, leur soudure étant produite par friction mécanique sous pression des deux pièces. Ce procédé, applicable à des pièces de bois plates, d'essences identiques ou différentes, se prête à la fabrication de meubles et à la menuiserie. Cependant, le joint obtenu n'est pas de classe "extérieur", ce qui le réserve à un usage "intérieur". En effet, un joint destiné à une utilisation extérieure ou en milieu à humidité variable doit présenter une résistance élevée à l'eau. L'objectif principal de cette thèse est d'étudier la résistance à l'eau du bois soudé. A cet effet, des méthodes d'essais complémentaires et non-destructrices ont été utilisées, comme le scanner ou l'imagerie par résonance magnétique (IRM). L'influence des paramètres de soudage et des propriétés du bois sur, d'une part, la formation et la propagation des fissures dans la ligne de soudure, et sur, d'autre part, la densité et l'absorption d'eau de la soudure a été ainsi étudiée. Les expériences de cette thèse seront menées sur des échantillons de pin (Pinus sylvestris) de dimensions 200 mm x20 mm x 40 mm, coupés dans la direction longitudinale du fil du bois. La Norme Européenne EN 205 a servi de cadre pour déterminer la résistance des échantillons de pin en traction-cisaillement. Les méthodes d'essais (non-destructrices) ont été utilisées selon leur pertinence: le scanner a servi à étudier la formation et la propagation des fissures; l'imagerie par résonance magnétique (IRM) a permis quant à elle de caractériser la pénétration et l'infiltration d'eau dans le bois soudé.Le mécanisme d'adhérence du pin a été étudié grâce à la RMN MAS (spectrométrie à résonance magnétique nucléaire avec polarisation croisée et rotation à l?angle magique) du carbone13 et à la micro-densitométrie par rayons X. Ces différentes méthodes, non destructrices, offrent l'avantage d'une analyse non invasive et l'élimination de facteurs parasites liés à la préparation et à la coupe du bois. Voici en résumé les résultats obtenus les plus marquants: (1) Le scanner et l'imagerie par résonance magnétique (IRM) sont des méthodes de recherche particulièrement polyvalentes et adaptées à l'étude des bois soudés. (2) L'utilisation de bois de coeur, une pression de soudage de 1.3 Mpa et un temps de soudage de 1.5 s permettent d'augmenter la résistance à l'eau du pin soudé. (3) Des tests d'optimisation ont montré que la résistance du pin en traction-cisaillement est plus sensible aux variations de temps de soudage qu'au temps de refroidissement et qu'elle peut être optimisée à plus de 9.7 MPa en respectant une pression de 1.3 Mpa, un temps de soudage > 3.5 s et un temps de refroidissement < 60 s. (4) La résistance à l'eau du bois soudé peut être améliorée dans une certaine mesure en faisant varier paramètres de soudage et propriétés des essences, mais dans tous les cas, le recours à un imperméabilisant naturel et écologique reste nécessaire. (5) Le pin soudé possède une résistance à l'eau et en traction-cisaillement inhabituellement élevée, cela pouvant s'expliquer par une teneur en composés extractifs augmentée. (6) Des essais sous IRM ont montré que les causes de rupture du joint varient suivant l'essence: faible résistance à l'eau de la ligne de soudure dans le cas du hêtre soudé, retrait et expansion du bois dans le cas du pin soudé. (7) Les extractifs du pin améliorent nettement la résistance à l'eau du joint soudé, mais à un niveau qui ne lui permet cependant pas la certification "extérieur" sans protection. En revanche, il peut être certifié "semi-extérieur" avec protectionWood welding is a mechanical friction process allowing the assembly of timber without any adhesives. The process consists of applying mechanical friction, under pressure, alternately to the two wood surfaces to be welded. This process can be applied to weld two flat pieces of timber, originating from the same or different tree species, and can be used in the manufacture of furniture and wood joinery. The only limitation is that the joint is not exterior-grade, but only suitable for interior joints. Exterior use, or use in an environment with varying humidity demands water resistance of the welded joints. The main objective of this thesis is to study the water resistance of the welded wood. This is complemented with special attention to non-destructive test methods such as X-ray Computed Tomography (CT-) scanning and Magnetic Resolution Imaging (MRI). The influence of welding parameters and wood properties on crack formation and crack propagation in the weldline was investigated. The influence of these parameters on weldline density and water absorption in the weldline were also studied. Investigations in this thesis are based on welded samples of Scots pine (Pinus sylvestris) of the dimensions 200 mm × 20 mm × 40 mm which were cut in the longitudinal direction of the wood grain. The tensile-shear strength of the welded Scots pine samples were determined using European standard EN 205. Different non-destructive methods such as X-ray Computed Tomography (CT-) scanning to study crack formation and propagation, and magnetic Resolution Imaging (MRI) to characterize water penetration and the distribution mechanism in welded wood were used. Solid state CPMAS 13C NMR spectrometry and X-ray microdensitometry investigations were carried out to study the mechanism of adhesion in Scots pine. These various non-destructive methods offer the advantage of non-invasive analysis and the elimination of any artifacts present due to preparation and sectioning. The most important results are summarized as follows: (1) X-ray Computed Tomography (CT-) scanning and Magnetic Resolution Imaging (MRI) are versatile research methods applicable to investigations of welded woods. (2) Water resistance of welded Scots pine can be increased using heartwood, a welding pressure of 1.3 MPa, and a welding time of 1.5 s. (3) Optimization tests showed that the tensile-shear strength of Scots pine was more sensitive to welding time changes than holding time and could be optimized to more than 9.7 MPa using 1.3 MPa welding pressure, > 3.5 s welding time, and < 60 s holding time. (4) Changing welding parameters and wood properties can increase water resistance of welded wood to some extent, but treating the weldline with certain natural and environmentally-friendly water repellents is still necessary. (5) Welded Scots pine shows unusually high water resistance and tensile-shear strength. This may be explained by there being more extractives compounds in Scots pine. (6) MRI experiments showed that the origin of the joint failure in welded beech is poor water resistance of the weldline, while swelling and shrinkage of wood are the main reasons for joint failure of welded Scots pine. (7) Extractives in Scots pine dramatically improve water resistance of the welded joint, but not to a level to classify the joint as an unprotected exterior grade. However, it can qualify as a joint for protected semi-exterior application
33
Beech, Scott Jay. "Oil removal for produced water treatment and micellar cleaning of ultrafiltration membranes". Thesis, Texas A&M University, 2006. http://hdl.handle.net/1969.1/4249.
Testo completoAbstract (sommario):
Produced water is a major waste produced from oil and natural gas wells in the state of Texas. This water could be a possible source of new fresh water to meet the growing demands of the state after treatment and purification. This thesis describes a research project that evaluated the treatment of brine generated in oil fields (produced water) with ultrafiltration membranes. The characteristics of various ultrafiltration membranes for oil and suspended solids removal from produced water were studied to test whether they could be used in a pretreatment method. The research measured the effect of pressure and flow rate on performance of three commercially available membranes for treatment of oily produced water. Oil and suspended solids removal were measured by using turbidity and oil in water measurements taken periodically. The study also analyzed the flux through the membrane and any effect it had on membrane performance. The research showed that an ultrafiltration membrane provided turbidity removal of over 99% and oil removal of 78% for the produced water samples. The results indicated that the ultrafiltration membranes would be useful as one of the first steps in purifying the water. Membrane cleaning of produced water-fouled membranes by micellar solutions was investigated. A neutral pH and ambient temperature micelle solution for effective cleaning of oily water-fouled membranes was developed and studied. The performance of cleaning solutions on ultrafiltration membranes was investigated on laboratory size membrane testing equipment. Different micro emulsion solutions were studied to evaluate the effect of solution properties on cleaning performance. Three types of multiple membranes were studied, each having the same polyvinylidene fluoride (PVDF) material but with different nominal separation or flux characteristics. The data showed that the use of a micelle solution to clean the produced water-fouled membranes was a feasible and effective method. The study showed with further adjustment of the micelle solution the cleaning effectiveness could be optimized to provide double the effectiveness of current industry methods for membranes fouled by produced water.
34
Wang, Yuxin. "Source Water Quality Assessment and Source Water Characterization for Drinking Water Protection". Research Showcase @ CMU, 2014. http://repository.cmu.edu/dissertations/416.
Testo completoAbstract (sommario):
Source water quality plays a critical role in maintaining the quality and supply of drinking water, yet it can be negatively affected by human activities. In Pennsylvania, coal mining and treatment of conventional oil and gas drilling produced wastewaters have affected source water quality for over 100 years. The recent unconventional natural gas development in the Marcellus Shale formation produces significant volumes of wastewater containing bromide and has the potential to affect source water quality and downstream drinking water quality. Wastewater from coal-fired power plants also contains bromide that may be released into source water. Increasing source water bromide presents a challenge as even small amounts of bromide in source water can lead to carcinogenic disinfection by-products (DBPs) in chlorinated finished drinking water. However, bromide is not regulated in source water and is not removed by conventional drinking water treatment processes. The objective of this work is to evaluate the safe bromide concentration in source water to minimize the cancer risk of trihalomethanes - a group of DBPs - in treated drinking water. By evaluating three years of water sampling data from the Monongahela River in Southwestern Pennsylvania, the present analysis reached three conclusions. First, bromide monitoring for source water quality should be taken at drinking water intake points. Water sample types (river water samples vs drinking water intake samples) can lead to different water quality conclusions and thus affect regulatory compliance decision-making. Second, bromide monitoring at drinking water intake points can serve as a predictor for changes in heavily brominated trihalomethanes concentrations in finished water. Increasing bromide in source water can serve as an early warning sign of increasing formation of heavily brominated trihalomethanes and their associated cancer risks in drinking water. Finally, this work developed a statistical simulation model to evaluate the effect of source water bromide on trihalomethane formation and speciation and to analyze the changing cancer risks in water associated with these changing bromide concentrations in the Monongahela River. The statistical simulation method proposed in this work leads to the conclusion that the bromide concentration in source water must be very low to prevent the adverse health effects associated with brominated trihalomethanes in chlorinated drinking water. This method can be used by water utilities to determine the bromide concentration in their source water that might indicate a need for process changes or by regulatory agencies to evaluate source water bromide issues.
35
Wang, Chengtao. "Assessment of the Occurrence and Potential Effects of Pharmaceuticals and Personal Care Products in South Florida Waters and Sediments". FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/689.
Testo completoAbstract (sommario):
A LLE-GC-MS method was developed to detect PPCPs in surface water samples from Big Cypress National Park, Everglades National Park and Biscayne National Park in South Florida. The most frequently found PPCPs were caffeine, DEET and triclosan with detected maximum concentration of 169 ng/L, 27.9 ng/L and 10.9 ng/L, respectively. The detection frequencies of hormones were less than PPCPs. Detected maximal concentrations of estrone, 17β-estradiol, coprostan-3-ol, coprostane and coprostan-3-one were 5.98 ng/L, 3.34 ng/L, 16.5 ng/L, 13.5 ng/L and 6.79 ng/L, respectively.
An ASE-SPE-GC-MS method was developed and applied to the analysis of the sediment and soil area where reclaimed water was used for irrigation. Most analytes were below detection limits, even though some of analytes were detected in the reclaimed water at relatively high concentrations corroborating the fact that PPCPs do not significantly partition to mineral phases.
An online SPE-HPLC-APPI-MS/MS method and an online SPE-HPLC-HESI-MS/MS method were developed to analyze reclaimed water and drinking water samples. In the reclaimed water study, reclaimed water samples were collected from the sprinkler for a year-long period at Florida International University Biscayne Bay Campus, where reclaimed water was reused for irrigation. Analysis results showed that several analytes were continuously detected in all reclaimed water samples. Coprostanol, bisphenol A and DEET’s maximum concentration exceeded 10 µg/L (ppb). The four most frequently detected compounds were diphenhydramine (100%), DEET (98%), atenolol (98%) and carbamazepine (96%). In the study of drinking water, 54 tap water samples were collected from the Miami-Dade area. The maximum concentrations of salicylic acid, ibuprofen and DEET were 521 ng/L, 301 ng/L and 290 ng/L, respectively. The three most frequently detected compounds were DEET (93%), carbamazepine (43%) and salicylic acid (37%), respectively. Because the source of drinking water in Miami-Dade County is the relatively pristine Biscayne aquifer, these findings suggest the presence of wastewater intrusions into the delivery system or the onset of direct influence of surface waters into the shallow aquifer.
36
Veum, Kristen Sloan. "Disinfection by-product precursors and formation potentials of Missouri reservoirs". Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4534.
Testo completoAbstract (sommario):
Thesis (M.S.) University of Missouri-Columbia, 2006.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 29, 2007) Includes bibliographical references.
37
Mbonimpa, Eric Gentil. "Characterization of disinfection by-product precursors from Missouri streams". Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/4908.
Testo completoAbstract (sommario):
Thesis (M.S.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 10, 2009) Includes bibliographical references.
38
Wise, Lynn V. "Characterization of sludges produced when using polyaluminum chloride coagulants". Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/41514.
Testo completoAbstract (sommario):
The dewatering characteristics of polyaluminum chloride (Hyper⁺Ion 1050A) sludges were investigated using lab-scale tests including specific resistance to filtration (r*), capillary suction time (CST), and sludge pH. The effects of chemical conditioning (lime and cationic polymer) and mixing intensity (Gt) upon the sludge dewatering characteristics in a pilot-scale plate and frame press were also studied.
The dewatering characteristics of the Hyper⁺Ion sludges were found to be dependent upon the influent water turbidity conditions; specifically, the ratio of aluminum coagulant to total dry solids in the sludge. Lime was an effective conditioner for doses that produced a sludge pH value in the range of 11.5 to 11.8 which, again, was a direct function of the aluminum coagulant fraction in the sludge. Cationic polymer and a combination of lime and polymer were also effective conditioning schemes when the appropriate dose and mixing intensity were applied.Master of Science
39
Ullah, Asmat. "Separation of oil drops from produced water using a slotted pore membrane". Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/15687.
Testo completoAbstract (sommario):
Microfiltration is one of the most important processes in membrane sciences that can be used for separating drops/particles above 1 ??m. Depth microfiltration membranes retain drops/particles inside the surface of the membrane, the process is expensive and membranes quickly become fouled. On the other hand, surface microfiltration membranes stop drops/particles on the surface of the membrane and the process is less fouling. Higher permeate flux and lower trans-membrane pressure is obtained with a shear enhanced microfiltration technique. Production of specific size of drops and stability of the drops are very important in testing the microfiltration of crude oil drops/water emulsions. Oil drops from 1-15 ??m were produced with a food blender, operated at its highest speed for the duration of 12 mins. In addition, vegetable oil drops were stabilised with 1% polyvinyl alcohol (PVA), Tween 20 and gum Arabic, stability was assessed on the basis of consistency in the size distribution and number of drops in each sample analysed at 30 mins interval. A slotted pore Nickel membrane with the slot width and slot length of 4 and 400 ??m respectively has been used in the filtration experiments. The slot width to the slot length ratio (aspect ratio) of the used membrane is 100. Vibrating the membrane at various frequencies created shear rates of different intensities on the surface of the membrane. Membrane with a tubular configuration is preferred over the flat sheet because it is easy to control in-case of membrane oscillations both at lab and industrial scale. Besides this, a tubular membrane configuration provides a smaller footprint as compared to the flat sheet. The influence of applied shear rate on slots/pore blocking has been studied. Applying shear rate to the membrane reduced the blocking of the slots of the membrane; and reduction of slots blocking is a function of the applied shear rate. At higher shear rate, lower blocking of the slots of the membrane was verified by obtaining lower trans-membrane pressure for constant rate filtration. The experiments are in reasonable agreement with the theoretical blocking model. Divergence of the experimental data from the theory may be due to involvement of deforming drops in the process. During microfiltration of oil drops, the drops deform when passing through the slots or pores of the membrane. Different surfactants provided different interfacial tensions between the oil and water interface. The influence of interfacial tension on deformation of drops through the slots was studied. The higher the interfacial tension then the lower would be the deformation of drops through the slots. A mathematical model was developed based on static and drag forces acting on the drops while passing the membrane. The model predicts 100% cut-off of drops through the membrane. Satisfactory agreement of the model with the experiments shows that the concept of static and drag force can be successfully applied to the filtration of deformable drops through the slotted pore membranes. Due to the applied shear rate, inertial lift migration velocities of the drops away from the surface of the membrane were created. Inertial lift velocities are linear functions of the applied shear rate. A mathematical model was modified based on inertial lift migration velocities. The critical radius of the drops is the one above which drops cannot pass through the surface of the membrane into the permeate due to the applied shear rate and back transport. The model is used as a starting point and is an acceptable agreement with the experiment. The model can be used to predict the 100% cut-off value for oil drops filtration and a linear fit between this value and the origin on a graph of grade (or rejection) efficiency and drop size to slot width ratio was used to predict the total concentration of dispersed oil left after filtration. Hence, it is shown how it is possible to predict oil discharge concentrations when using slotted filters.
40
Wilson, Reese Nathaniel. "Clarification of Recreational Pool Water using Biological Additives Produced by BiOWiSH(TM)". DigitalCommons@CalPoly, 2015. https://digitalcommons.calpoly.edu/theses/1477.
Testo completoAbstract (sommario):
Effects of commercially available bacterial products were investigated on two common recreational pool contaminants: sunscreen and cyanuric acid (CYA). Microbial products developed by BiOWiSH Technologies, Inc. were tested for enhancing mechanical filtration and water clarification in bench-scale bioreactors, with conditions mimicking those of recreational pool water. Bacterial consortia included proprietary mixes of Bacillus, Lactobacillus and Pseudomonas, and other genera of bacteria. BiOWiSH products are either fermented on a solid substrate consisting of rice bran and soy meal, or they are mixed with a soluble diluent. Twenty-nine BiOWiSH products were tested throughout forty experiments.
Experiments were carried out to determine both the efficacy of BiOWiSH products for turbidity reduction and the mechanism by which BiOWiSH removes sunscreen from solution. In trials without mechanical filtration, the only product which showed a reduction in turbidity relative to the control, albeit inconsistently, was the solid substrate version of BiOWiSH Aqua FOGTM (Thai FOG). Experiments on BiOWiSH coupled with mechanical filtration showed a 79% average reduction of turbidity in the first 24 hrs. BiOWiSH products containing solid substrate, both active and abiotic, showed an average turbidity reduction of 90% in the first 24 hrs. In the same timeframe, soluble BiOWiSH products showed a 79% average reduction in turbidity. Thus, the solid v substrate provided an additional 11% reduction in turbidity over soluble products and un-amended mechanical filtration. Through experimentation and scanning electron microscopy, it was concluded that the primary mechanism of clarification by the solid substrate is adsorption of sunscreen to the substrate surface.
Further experiments were performed in anaerobic and aerobic environments to determine whether BiOWiSH products can remove cyanuric acid from solution through adsorption or biodegradation. Two measurement methods, turbidimetric and HPLC (high performance liquid chromatography) were used to independently quantify CYA. A reverse-phase HPLC method was developed which utilizes a phosphate buffer and methanol for the separation of cyanuric acid from nitrate and other chemical species. The solid BiOWiSH Aqua FOG product (prod. in Thailand) interfered with the turbidimetric analysis, showing false decreases in CYA. Using HPLC, there was no measureable biodegradation or adsorption of CYA by BiOWiSH products in these bench-scale tests. Significant systematic error in the HPLC analysis prevented conclusive findings; therefore, the ability of BiOWiSH products to reduce CYA from solution remains inconclusive.
41
Farrell-Poe, Kitt. "Antibacterial Products in Septic Systems". College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2010. http://hdl.handle.net/10150/146423.
Testo completoAbstract (sommario):
2 pp.Originally published: 2001
An onsite sewage treatment system or "septic system" is effective way to safely recycle household wastewater back into the natural environment. The key to effective treatment is proper design, system installation, responsible operation, and periodic maintenance. This article provides information about how to improve septic system performance by taking simple steps at home.
42
Ferreira, Francisco Cardoso. "Chlorine dioxide and by-products in water distribution systems". Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-11242009-020052/.
Testo completo
43
Diehl, Alicia Catherine. "Factors affecting disinfection by-product formation during chloramination of drinking water /". Full text (PDF) from UMI/Dissertation Abstracts International, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3008314.
Testo completo
44
Al, Aufi Mohammed. "Treating oil-field co-produced water by forward osmosis for low-salinity water injection and enhanced oil recovery". Thesis, University of Surrey, 2017. http://epubs.surrey.ac.uk/842050/.
Testo completoAbstract (sommario):
Co-produced water re-injection is a mature recovery technique for oil fields. Co-produced water that is not re-injected is the largest wastage stream in the oil industry. Handling, treatment and management (especially re-injection back into the reservoir) is an expensive operation. PWRI is a secondary oil recovery method with a small recovery factor in the range of 15-25% and contributes to many surface and subsurface issues, e.g., scaling and reservoir plugging, resulting in the decline of water injectivity, and thus lower oil recovery. This reduction, of course, impinges significantly on the revenue stream of major oil corporations. However, low-salinity (LowSal) water injection is an emerging method that boosts oil recovery by reducing the downsides of produced water re-injection. Using forward osmosis to produce low-salinity water for injection is a novel idea, in which the co-produced water will be the draw solution. In this concept, low-salinity water from water wells (brackish water) is used as the feed to dilute the co-produced water. The diluted co-produced water will then be re-injected as LowSal water. The obviously cheaper alternative of direct dilution of the co-produced water with the brackish water might not produce a water compatible with the oil reservoir in both ionic composition and strength. Data have been collected from different oil fields with various co-produced water and formation characteristics. Different co-produced water treatments were observed in each oil field due to differences in co-produced water chemistry. The water sample for analysis was taken at the skim tanks prior to the water injection stage. A theoretical resistance-in-series model for the forward osmosis stage is presented, which has been adapted from the literature, which incorporates the mass transfer equations, in which the boundary layer and thin-film theory for the membrane intrinsic layers are integrated. An improved shell mass transfer correlation is introduced in addition to the incorporation of a modified reflection coefficient into the resistance-in-series model. The collected data were then incorporated into the theoretical model to calculate and evaluate the forward osmosis performance and, in turn, the water chemistry before re-injection. A forward osmosis rig has been erected to use the latest hollow fibre membrane supplied by the Toyobo Company (Japan). Water and solute flux were measured to validate the model estimations. The model estimated results were at 95% confidence to the measured values. Analytical investigations (ion analysis) for the membrane filtrate at various flowrates and applied pressures were performed to determine the forward osmosis filtrate ion composition. The FO filtrate compositions were then simulated using ScaleChem studio software from OLI for scaling tendency. The software predicted a remarkable reduction in the scaling tendency in the injection water infrastructure (including the oil reservoir) and by more than 50% compared to conventional co-produced water re-injection. Parallel to the ScaleChem predictions, the FO filtrate water was experimentally investigated for scaling using the Differential Scaling Loop rig, in a third-party lab. The DSL results are in good agreement with the ScaleChem predictions. The experimental scaling tendency results show that the injection of forward osmosis filtrate has the minimum occurrence of scaling both in the surface and subsurface. This new concept to produce LowSal produced water re-injection has the potential to improve oil recovery by minimizing the oil reservoir plugging due to scaling.
45
Ates, Nuray. "Disinfection By-products Formation In Low - Bromide And Low - Suva Waters". Phd thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609489/index.pdf.
Testo completoAbstract (sommario):
The main objective of this study was to conduct a systematic investigation of the disinfection by-products (DBPs) formation in low-bromide and low- specific ultraviolet absorbance (SUVA) waters and the control of DBP precursors by nanofiltration (NF) and ultrafiltration (UF) processes in such waters. To this end, firstly, the effect of bromide ion on the formation and speciation of DBPs was investigated. In fractionated Alibeyköy source water, increasing bromide concentrations in NOM fractions increased concentrations of trihalomethanes (THMs), haloacetic acids (HAAs) and adsorbable organic halides (AOX) and resulted in a shift toward the formation of brominated species. Secondly, the impacts of SUVA and differential UV spectroscopy (&
#916
UV), which has been shown to correlate well with DBP formation has been elucidated in terms of DBP formation and speciation. Alibeykö
y and Karacaö
ren waters were fractionated employing various separation methods and it has been shown that SUVA did not correlate well with the formation and speciation of THMs and HAAs in tested low-SUVA waters. Similarly, no correlations were found among THMs/HAAs formations and &
#916
UV. Finally, the NOM rejection performances of NF and UF membranes were investigated. NF and UF membranes (<
2000 dalton) was found to be suitable for the removal NOM from surface waters having low SUVA and low bromide contents. While higher molecular weight (HMW) fraction was successfully rejected (>
90%) by all membrane types, lower molecular weight (LMW) fraction could be removed with ranging efficiencies from 1.5 to 30%. NF membranes provided DOC, UV254 absorbance, THM, and HAA reductions up to 90%.
46
Johnson, Thomas G. "Heat Transfer in Brine Solutions at Supercritical Pressure". Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1439504843.
Testo completo
47
Gai, Ke. "Effect of Mercury Speciation on its Transport in Soil and Removal from Produced Water". Research Showcase @ CMU, 2017. http://repository.cmu.edu/dissertations/1066.
Testo completoAbstract (sommario):
Mercury (Hg) is distributed globally through atmospheric transport. The broad range of environmental conditions will lead to various possible speciation of mercury, which will ultimately affect the toxicity and transport of mercury. Hg toxicity, transport and speciation have been widely studied. However, information about effects of Hg speciation on its environmental behavior in unsaturated porous media and on its removal from wastewater stream is still limited. The present work contributes towards understanding the impact of Hg speciation on both the transport of Hg species in unsaturated porous media (e.g., surface soil) and removal of Hg species in wastewater streams. This knowledge is necessary to assess the possible environmental risks of Hg in the environment, where different Hg species can exist and have different properties and impacts on water quality and ecosystems. The first objective of this research was to determine the effect of Hg speciation on its retention in partially saturated soils. The retention of Hg species in model porous media and in real soil was assessed in column breakthrough experiments. Deposition (retention) rates for each Hg species were calculated to evaluate the influence of Hg speciation, porous medium composition and influent solution on the mobility of Hg species in porous media. This study provided information about the relative retention of each Hg species in soils, and identified natural-organic-matter-bound Hg as the most mobile Hg species and that with the greatest potential for vertical migration to groundwater. The second objective of this research was to determine how Hg speciation affects its ability to be removed from water via adsorption by activated carbon and organoclay. The effects of Hg speciation, water quality parameters and adsorbent type on the removal of Hg were compared to explore the potential removal efficacy and mechanism. The result indicated Hg removal efficacy was influenced by Hg speciation differently depending on the solution conditions. Therefore, using total dissolved Hg(II) to predict Hg removal efficacy may not provide a reliable estimate of adsorption. Organoclay was shown to have a highly reactive surface and the highest adsorption capacity per unit specific surface area among the tested adsorbents. The third objective was to determine the Hg speciation in produced water from an oil production well, and to study the influence of Hg speciation on its removal from produced water by adsorbents. Mercury species in a produced water sample were identified as mainly particulate species and hydrophobic species. The removal of the amended Hg species in produced water was measured to evaluate the impact of Hg speciation on its removal. This study showed that produced water composition affected Hg speciation and formed hydrophobic Hg was more difficult to remove than initially added hydrophilic Hg species in produced water.
48
Okaiyeto, Kunle. "Evaluation of flocculating potentials and charecterization of bioflocculants produced by three bacterial isolates from Algoa Bay, South Africa". Thesis, University of Fort Hare, 2016. http://hdl.handle.net/10353/2633.
Testo completoAbstract (sommario):
Flocculation has been widely adopted as one of the most effective methods to remove colloidal particles in water or wastewater treatment. Synthetic flocculants are conventionally used because of their high flocculating efficiency and cost-effectiveness. However, they have been reported to have hazardous properties and implicated in some serious health problems including senile dementia and neuro-toxicity, as well as being recalcitrant in the environment. Consequently, efforts are being geared away from the use of synthetic flocculants in water and wastewater treatment. Hence, the need for safe and eco-friendly flocculants has become imperative. Compared with synthetic flocculants, bioflocculants have special advantages such as safety, biodegradability and harmlessness to the environment and humans; attributes which make them potential alternatives in water treatment, downstream as well as fermentation processes. In the current study, the potentials of bacterial isolates recovered from Algoa Bay in the Eastern Cape Province of South Africa for bioflocculant production were investigated. The bacterial isolates were identified by polymerase chain reaction (PCR) as belonging to the Bacillus genus. The analysis of 16S ribosomal deoxyribonucleic acid (rDNA) nucleotide sequence of isolate M72 showed 99 percent similarity to Bacillus toyonensis strain BCT-7112 and was deposited in the GenBank as Bacillus toyonensis strain AEMREG6 with accession number KP406731. Likewise, the 16S rDNA nucleotide sequences of isolates M69 and M67 showed 98 percent sequence similarity to Bacillus licheniformis strain W7 and Bacillus algicola strain QD43 respectively; and M67 isolate was subsequently deposited in the GenBank as Bacillus sp. AEMREG7 with accession number KF933697.1. The results of the nutritional requirements and fermentation conditions revealed that optimum inoculum size for REG-6 production was 4 percent (v/v), while 5 percent (v/v) and 3 percent (v/v) were most favourable for MBF-W7 and MBF-UFH production respectively. Glucose was the best carbon source for the production of bioflocculants (REG-6 and MBF-UFH) by Bacillus toyonensis AEMREG6 and Bacillus sp. AEMREG7 respectively, while maltose supported optimum bioflocculant (MBF-W7) production by Bacillus specie. Inorganic nitrogen (NH4NO3) was the favoured nitrogen source for both REG-6 and MBF-W7 production, while mixed nitrogen sources [yeast extract + urea + (NH4)2SO4] supported the maximum production of MBF-UFH. The initial medium pH for REG-6 was 5, while MBF-W7 and MBF-UFH were both maximally produced at the initial pH of 6. After a 96 h cultivation period under optimal culture conditions, 3.2 g of purified REG-6 with a maximum flocculating activity of 77 percent was recovered from 1 L fermented broth of Bacillus toyonensis AEMREG6. Yields of 3.8 g and 1.6 g pure bioflocculants with the respective highest flocculating activities of 94.9 percent and 83.2 percent were also obtained from 1 L, 72 h-fermented broths of Bacillus licheniformis and Bacillus sp. AEMREG7 respectively. Furthermore, all the three bioflocculants (REG-6, MBF-W7 and MBF-UFH), displayed thermal stability within the temperature range of 50 to 100 oC, with strong flocculating activities of over 80 percent against kaolin suspension over a wide range of pH range (3–11) and relatively low dosage requirements of 0.1-03 mg/ml in the presence of divalent cations in the treatment of kaolin clay suspension and Thyme River waters. Chemical composition analyses of the bioflocculants showed them to be glycoproteins with a predominantly polysaccharide backbones as shown by the following carbohydrate/protein (w/w) ratios: 77.8 percent:11.5 percent (REG-6); 73.7 percent:6.2 percent (MBF-W7) and 76 percent:14 percent (MBF-UFH).
49
Peterson, Benjamin L. "Development and Optimization of a Produced Water, Biofilm Based Microalgae Cultivation System for Biocrude Conversion with Hydrothermal Liquefaction". DigitalCommons@USU, 2018. https://digitalcommons.usu.edu/etd/7237.
Testo completoAbstract (sommario):
Extraction of oil and gas in Utah’s Uintah Basin results in large quantities of wastewater, or produced water, with nutrients and residual organic chemical that represent a significant resource for producing energy-related and value-added products. Produced water was obtained as a biomass producing nutrient source from industries operating in Utah’s Uintah Basin. Within the Uintah Basin (defined as Uintah and Duchesne Counties within Utah) approximately 93 million barrels of water were produced in 2013 while only 11% of the water was disposed of through evaporation, with the national average at 2%. The rest is reinjected into the subsurface.
The goal of this project was to design a system that utilizes produced water as a nutrient source for growing microalgae biomass in a biofilm form using a Rotating Algal Biofilm Reactor (RABR). The biomass would then be harvested and converted into biocrude oil using hydrothermal liquefaction (HTL). The objectives were to (1) cultivate biomass on produced water, (2) optimize the reactor to reduce energy costs to operate while increasing biomass productivity, and (3) increase feedstock quality for HTL.
The RABR was constructed out of polystyrene disks, and experimentation was carried out to optimize rotational speed of the reactor. Two strains of algal biomass were identified as biofilm formers and grown using produced water as the nutrient source. The biomass was then utilized as a HTL feedstock that gave an average yield of 34.5% ash free dry weight.
50
Sowder, Jonathan T. "The origin and fate of arsenic in coalbed natural gas produced water ponds". Laramie, Wyo. : University of Wyoming, 2009. http://proquest.umi.com/pqdweb?did=1935323111&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
Testo completo