Dissertations / Theses: 'Waste chemical production'

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Lin, Zhongye. "Microalgal Growth and Lipid Production from Organic Waste." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1385429109.

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Lucas, Carlos Krus Galvão. "Biogas production from potato peel waste." Master's thesis, Faculdade de Ciências e Tecnologia, 2014. http://hdl.handle.net/10362/12337.

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Stamouli, Konstantina. "Fuel production and optimisation from mixed plastic waste." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8268/.

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Increasing plastic consumption has created an alerting problem with waste disposal of the mixed waste plastics once the recyclable fractions have been recovered. The percentage sent to landfill of the generated mixed plastic waste amounts to one third of the total. Liquid fuel recovery from mixed plastic waste is possible using pyrolysis as a tertiary recycling process. The focus of this study was to obtain useful liquid product recovered from the pyrolysis of a variety of commercial mixed plastic waste utilising a pilot scale fluidised bed reactor of 1kg/hr processing capacity. The influence of residence time (1.78 to 2.74s), feedstock variation and reaction temperature (500 – 550oC) were investigated to optimise the quality of the wax products. Characterisation of the mixed plastic feedstocks through TGA, DSC and FTIR analysis was carried out to lay the foundation of the pyrolysis conditions. Understanding the fuel quality and product distribution was essential in assessing the key properties such as melting point and viscosity in the optimisation process. Key findings of the research concluded that increasing residence time has the strongest effect on reducing the melting point (up to 14oC) of the liquid product across all studied feedstocks although the magnitude of the effect greatly depends upon the initial feedstock composition. Changes is the average melting point correspond to a shift in the average carbon number distribution of the product. Feedstock and process parameters variability were also found to greatly affect the final product quality resulting in a versatile product composition as well as the product yields that varied between 27 and 60% w.t.

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Bolaji, Efeoluwa Omotola. "Anaerobic fermentation of organic wastes for chemical production by undefined mixed microbial cultures." Thesis, University of Aberdeen, 2018. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=236961.

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Zheng, Sheng. "Biodiesel production from waste frying oil: Conversion monitoring and modeling." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/26416.

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Biodiesel is a clean-burning substitute for petroleum-based diesel produced from virgin or waste vegetable oils and animal fats. One obstacle to the development of biodiesel is its high cost compared to petroleum diesel. Using waste frying oil instead of virgin oil can significantly reduce the high production cost. In our lab, promising preliminary results have indicated that transesterification of waste frying oil catalyzed by sulphuric acid has sufficient commercial feasibility to warrant further investigation. In order to better understand the acid-catalyzed transesterification process and to optimize the process yield, an empirical study of the reaction kinetics was carried out. A mixture design for feed compositions at various temperatures was used to determine their effects on conversion rates and yields. Empirical models were built to describe the relationships of interest. Rate of mixing, feed composition and temperature were chosen as independent factors in this study. Intensity of mixing was found to have no significant effect on the yield over 100 rpm. The methanol to oil ratio and temperature were the most significant factors affecting the yield. Finally, a region of optimum operating conditions was determined from the models. Analytical methods played an important role in our study. The extent of the reaction was followed off-line by gel permeation chromatography (GPC) and compared to results using an off-line infrared sensor based on attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. The development, use and evaluation of the off-line method were discussed. The reproducibility of both methods was found to be excellent (≤1%); data obtained from both methods were found to be reliable. Finally, a comparison of the two methods showed good agreement (within 2%) in the monitoring of the transesterification reaction.

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Jitrwung, Rujira. "Optimized continuous hydrogen production by «Enterobacter aerogens» from glycerol-containing waste." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=95168.

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ABSTRACT Glycerol is the main by-product of biodiesel production. Enterobacter aerogenes has a known ability to convert glycerol (GL) in a fermentative process to yield hydrogen and ethanol. To demonstrate the potential of a continuous fermentative process to valorize crude-glycerol, hydrogen yield was optimized by determining the optimal cultivation conditions in serum bottles, which were then applied to the optimization of the operation of a 3.6-L continuous bioreactor for maximum hydrogen yield. Conditions optimized in bottles were grouped and tested using a Box-Behnken response surface methodology to determine the optimal concentration of inoculum volume (18%), O2 in transfer step (7.5% O2), Na2HPO4 (12 g/L), NH4NO3 (1.5 g/L) and FeSO4.7H2O (6.25 mg/L). Two levels of full factorial design with a middle point were used to optimize the concentration of trace salts including Na2EDTA (3.5 mg/L), CaCl2.2H2O (0 mg/L) and MgSO4.7H2O (200 mg/L) while a parametric study was used to determine the optimal amounts of two phosphate salts (Na2HPO4, KH2PO4). After a scale-up of 30x in batch mode, the optimal operating conditions of the 3.6-L bioreactor (50% working volume) were determined to be: fresh feed rate (0.44 mL/min), liquid recycle ratio (33%), pH (6.4), glycerol concentration (15 g/L), mixing speed (500 rpm), and waste reuse (0%). Using the optimized conditions we demonstrated the stability of the system over time and obtained the highest yields ever reported in CSTR, 0.86 mole hydrogen/mole GL and 0.74 mole ethanol/mole GL, and this at a significantly reduced media cost of $ 0.91 CAD/L (77% lower than previous studies).
ABRÉGÉ Le glycérol est le principal sous-produit de la production de biodiesel. Enterobacter aerogenes a une capacité connue à convertir le (glycérol) en hydrogène et en éthanol au cours d'une fermentation. Afin de démontrer le potentiel d'un procédé en continu de valorisation du glycérol, les conditions optimales de culture ont été déterminées dans des bouteilles afin d'optimiser le rendement en hydrogène et puis appliquées à un bioréacteur de 3.6 L. Les conditions de culture optimales, déterminées à l'aide de la méthodologie de réponse de surface de Box-Behnken, sont un volume d'inoculation de 18%, une concentration d'oxygène de 7.5% lors du transfert, et les concentrations suivantes de Na2HPO4 (12 g/L), NH4NO3 (1.5 g/L) et FeSO4.7H2O (6.25 mg/L). Un plan factoriel complet à deux niveaux avec point central a aussi été utilisé afin de déterminer les concentrations optimales de Na2EDTA (3.5 mg/L), CaCl2.2H2O (0 mg/L) et MgSO4.7H2O (200 mg/L) alors qu'une étude paramétrique a permis de déterminer la quantité optimale de deux sels de phosphate (Na2HPO4, KH2PO4). Suite à la mise à l'échelle 30x dans le bioréacteur opéré en mode batch, les conditions optimales du CSTR ont été identifiées comme étant un débit d'alimentation de 0.44 mL/min, un ratio de recyclage de liquide de 33%, un pH de 6.4, une concentration de glycérol de 15 g/L, une vitesse de mélange de 500 rpm ainsi qu'une réutilisation nulle du résidu liquide. En utilisant ces conditions optimales de culture et d'opération du bioréacteur opéré en continu, la stabilité du procédé sur une période prolongée d'opération a été confirmée. Dans ces conditions, les plus hauts rendements en hydrogène et en éthanol jamais rapportés dans un tel système, ont été obtenus, 0.86 mole hydrogène/mole GL and 0.74 mole éthanol/mole GL, et ce, à un coût en média de 75% inférieur aux études antérieures.

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Zhang, Yi. "Design and economic assessment of biodiesel production from waste cooking oil." Thesis, University of Ottawa (Canada), 2002. http://hdl.handle.net/10393/6138.

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Biodiesel is a recommended petroleum-based diesel substitute mainly because it is environmentally friendly and is a renewable, domestic resource. However, compared to petroleum-based diesel, biodiesel has a higher cost, which is the major obstacle to its commercialization. In this thesis, four different continuous alkali- and acid-catalyzed processes to produce biodiesel from virgin vegetable oil and waste cooking oil were designed and simulated. Process flowsheets, along with detailed operating conditions and equipment designs for each process were created. Technical assessment of these processes showed that the alkali-catalyzed process using virgin oil required the least amount of process equipment and no significant requirement for special materials of construction but had the highest raw material cost. The acid-catalyzed process using waste cooking oil proved to be technically feasible with a significantly lower raw material cost but required forty percent of the process equipment to be constructed from stainless steel. An economic assessment was also performed based on the results of process simulations. The alkali-catalyzed process using virgin vegetable oil was found to have the lowest fixed capital cost. However, in terms of total manufacturing cost, aftertax rate of return and break-even price of biodiesel, the acid-catalyzed process using waste cooking oil had the lowest operating cost, the best aftertax rate of return (i.e., 10%) and the lowest break-even price (i.e., $590/tonne). In summary, the acid-catalyzed process to produce biodiesel from waste cooking oil is technically feasible and economically attractive. Results from the sensitivity analyses of the various processes indicated that plant capacity, the price of feedstock oil and biodiesel price were the factors that most significantly affected the economic feasibility of biodiesel production.

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Van, Dyk Lizelle Doreen. "The production of granular activated carbon from agricultural waste products." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/52003.

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Thesis (MEng)--University of Stellenbosch, 2000.
ENGLISH ABSTRACT: Peach and apricot shells are agricultural waste products. These waste products accumulate around canneries and food-processing plants in South Africa. No effort is being made to utilise these waste products. This study is the first part of the product development from these products i.e. peach shell activated carbon and apricot shell activated carbon. By producing activated carbon from peach and apricot shells the solid waste problem is addressed, but most of all a profit can be made. But why activated carbon? Activated carbons are unique and versatile adsorbent with a vast amount of adsorption applications. It can be produced via a simple oxidation reaction with steam and the nature of peach and apricot shells are such that it is expected that activated carbons with good adsorption properties can be produced from it. The single largest consumer of activated carbon in South Africa is the gold mining industry that uses imported coconut shell activated carbon for gold adsorption in the gold recovery process. Activated carbon is also used as water purification adsorbents. During this study activated carbons were produced in a fluidized bed reactor at various activation conditions: 700 - 900°C, 0.0425 - 0.0629 g steamlg char.min and 30 - 60 min. This was done in order to find the optimum activation conditions within the activation parameter range. The optimal activated carbons were defined as peach and apricot shell activated carbons that showed good microporous as well as mesoporous character. The optimal activated carbons produced are: peach shell activated at 875°C, 0.0533 g stearnlg char. min, 60 min and apricot shell activated carbon at 850°C, 0.0533 g steamlg char.min, 60min. The possible use of these optimal activated carbons and two other activated carbons produced (Peach shell activated carbon 900°C, 0.0425 g steamlg char. min, 60 min and apricot shell activated carbon 900°C, 0.0425 g steamlg char.min, 60min) were tested in gold recovery and water purification. The gold adsorption properties of peach and apricot shell activated carbons were found to be better than two commercial coconut shell activated carbons (Chemquest 650 and GRC 22). No definite conclusions could, however, be drawn about the replacement of coconut shell activated carbon with peach or apricot shell activated carbon, because abrasion test work and thermal regeneration of the experimental carbons still have to be performed. The experimental activated carbons displayed good phenol adsorption characteristic, although further test work is required.
AFRIKAANSE OPSOMMING: Perske- en appelkoospitte is landbouafvalprodukte. Hierdie afvalprodukte versamel rondom inmaakfabrieke en voedselververkingsaanlegte. Tans word daar geen poging in Suid-Afrika aangewend om hierdie afvalprodukte te benut nie. Hierdie studie is die eerste deel van die ontwikkeling van die produkte: Perskepitdop-geaktiveerde koolstof en appelkoospitdop-geaktiveerde koolstof. Deur geaktiveerde koolstof van die perske- en appelkoospitdoppe te maak, word nie net 'n antwoord op die vastestofafvalsprobleem gevind nie, maar daar kan ook geld gemaak word. Hoekom geaktiveerde koolstof? Aktiveerde koolstowwe is veelsydige en unieke adsorbente met 'n groot verskeidenheid adsorpsie toepassings. Dit kan vervaardig word via 'n eenvoudige oksidasie reaksie met stoom en die aard van die perske- en appelkoospitdoppe is sodanig, dat verwag kan word om geaktiveerde koolstowwe met goeie adsorpsie eienskappe daarvan te kry. Die grootste enkelverbruiker van geaktiveerde koolstof in Suid-Afrika is die goudmynbedryf, wat kokosneutdop geaktiveerde koolstof invoer om goud te herwin. Geaktiveerde koolstof word ook gebruik vir watersuiwering. Tydens hierdie studie IS geaktiveerde koolstowwe by verskillende aktiveeringskondisies in 'n gevloeïdiseerde bed vervaardig: 700 - 900oe, 0.0425 - 0.0629g stoornlg gepiroliseerde pitdoppe.min en 30 - 60 mm. Die aktiveringskondisies is gevarieer om sodoende die optimale aktiveringskondisies binne die aktiveringsparameterreeks te kry. 'n Geaktiveerde koolstof is as optimaal geklassifiseer as dit 'n goeie mikro- sowel as mesostruktuur getoon het. Die optimaal geaktiveerde koolstowwe is: geaktiveerde koolstof vervaardig van perskepitdoppe by 875°e, 0.0533 g stoornlg gepiroliseerde pitdoppe.min, 60 mm en geaktiveerde koolstof vervaardig van appelkoospitdoppe by 850oe, 0.0533 g stoornlg gepiroliseerde pitdoppe.min, 60min. Die gebruik van die twee optimale geaktiveerde koolstowwe sowel as twee ander geaktiveerde koolstowwe (perskepitdop-geaktiveerde koolstof, 900oe, 0.0425 g stoornlg gepiroliseerde pitdoppe.min, 60 min en appelkoospitdop-geaktiveerde koolstof, 850°C, 0.0533 g stoom/g gepiroliseerde pitdoppe.min, 60min) is VIr goudadsorpsie en watersuiwering ondersoek. Die goudadsorpsie eienskappe van die perske-en appelkoospitdop-geaktiveerde koolstowwe was beter as die van twee kommersiële kokosneutdop-geaktiveerde koolstowwe (Chemquest 650 and GRC 22). Daar kan egter geen definitiewe gevolgtrekkings gemaak word oor die vervanging van kokosneutdop geaktiveerde koolstowwe met dié van perske of appelkoospitdoppe nie, aangesien daar nog toetsresultate oor die slytweerstand en reaktiverings eienskappe van die eksperimentele geaktiveerde koolstowwe uitstaande is. Die eksperimentele geaktiveerde koolstowwe toon goeie adsorpie ten opsigte van fenol, maar verdere toetswerk is egter nodig.

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Jourabchi, Seyed Amirmostafa. "Production and physicochemical characterisation of bio-oil from the pyrolysis of Jatropha curcus waste." Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/28825/.

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The increasing use of fossil fuels and the impending depletion of their reserves worldwide are driving alternative energy sources as one of the foremost consideration for research in energy, fuel, and power technology. Additionally, the increasing rate of harmful emissions especially carbon dioxide from the increased usage of fossil fuels have led to the need for more environmentally friendly replacement fuels. Presently, bio-oil originating from biomass has been proposed as an alternative fuel to fossil diesel. The aim of this research project is to optimally produce bio-oil in terms of quantity and quality from Jatropha curcas waste by using conventional and fast pyrolysis methods. Jatropha curcas shrub, which can be planted economically in tropical regions like Malaysia, is typically planted as a source of inedible oil for biodiesel production. The leftover pressed cake after oil extraction is an agricultural waste, which can be upgraded into fuel via pyrolysis. In this project, the pyrolysis parameters to achieve optimum quantity and quality of bio-oil from Jatropha curcas waste were determined. To achieve this, two fixed-bed pyrolysis rigs for conventional and fast pyrolysis processes were designed and fabricated, and a corresponding Design of Experiment was performed. By considering yield, calorific value, water content and acidity, the results from both methods were mathematically modelled after comparison and the optimum parameters for both methods were determined. The validated models of conventional and fast pyrolysis showed that optimum combined quantity and quality of bio-oil occur at reaction temperatures of 800 K and 747 K respectively but at the same nitrogen linear velocity of 0.0078 cm/s. At these optimum conditions, conventional and fast pyrolysis yield 50.08 wt% and 40.08 wt% of bio-oil with gross calorific values of 15.12 MJ/kg and 16.92 MJ/kg, water contents of 28.34 wt% and 28.02 wt%, and pH values of 6.77 and 7.01, respectively. The produced bio-oils from both rigs at their optimum points were dehydrated, and the physicochemical characteristics of the dehydrated bio-oils from both rigs were compared to standard specifications for burner biofuels. Based on ASTM D7554-10 standard for burner biofuel specifications, by reducing the sulphur contents, both dehydrated bio-oils can be used as burner fuel without any further processes. Finally, both 10% of optimised and dehydrated bio-oils emulsified in 90% diesel were tested and compared to EN590, the European standards for diesel used in commercial diesel engines and ASTM D6751-01, the standard biodiesel specifications. In addition to sulphur content, if the water content of both of these emulsified dehydrated bio-oils are removed, they can be commercially used as diesel fuel in diesel engines because their solid content, kinematic viscosity, ash content, flash point, cetane number and copper corrosion strip test results are within the range of EN590 standard.

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Rojas-Cuellar, Tania Raquel. "Utilisation of cellulose waste for the production of a chemical intermediate of economic interest." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/utilisation-of-cellulose-waste-for-the-production-a-chemical-intermediate-of-economic-interest(81b2984b-adf0-48a9-8e06-f3e9da548c19).html.

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Currently biomass is considered to be one of the main options to substitute the fossil fuels. Nevertheless, bioenergy is not the only alternative use for organic waste materials. In recent years, the utilisation of cellulolytic waste from industries, such as the paper industry and agriculture (in fields and in processing plants), is considered to be a good source of renewable carbon to produce chemical intermediates, such as glucose, lactic acid, ethanol and acetic acid, which can be returned to the productive chain. However, the principal obstacle in the use of this material for enzymatic degradation lies in the nature of the cellulose polymer. There are still many engineering, technological and chemistry related issues which remain to be resolved. The main objective of this study is to enable the production of glucose from the enzymatic hydrolysis of cellulose waste, arising from the waste of a recycle paper plant (paper crumb) by using Trichoderma reesei strain directly, instead of the commonly used mixture enzymes. This procedure, known as the single-step glucose production process, aims to reduce the costs associated in the use of pure enzymes and pre-treatments that are usually necessary to carry out the enzymatic degradation. The paper crumb is high in cellulose fibres (32%) with an alkaline characteristic, which carries a wide variety of impurities. This study recommends using existing knowledge with regards the enzymatic activity of the fungus and demonstrates its ability to degrade this substrate; regardless of the complex matrix linked to the cellulose polymer. Due to the nature of paper crumb a number of issues had to be solved during the development of the single-step production process. Firstly, the identification of an analytical method to monitor the enzymatic degradation of the paper crumb without interference of the inorganic compounds present in the substrate. The glucose analyser GL6 proved to be most suitable in this study. Secondly; the verification of the fungus’ ability to grow in this substrate by using PDA/Paper crumb plate, which allowed its adaptation gradually and reduced the time to produce enzymes. Finally, the evaluation of the enzymatic activity under acid and alkaline conditions was undertaken. It is demonstrated that the single-step process is feasible under acid conditions. The study also found that the fermentation time was the key parameter (up to 9 h.) to avoid the consumption of the glucose. The results show that the single-step process produces the same amount of glucose as the multi-step process (0.4 g/l), however the lower glucose production making it less economically attractive and less feasible to be expanded into an industrial scale. Nevertheless, the findings of this research contribute to establishing the basics for the optimisation of the glucose production process as an alternative for cellulose waste management. This adds economic value to the organic waste minimisation, which will lead to reduce cost in production processes.

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Lundberg, Johan. "Impact of increased production on TOC to the Waste Water Treatment Plant : Piteå 750." Thesis, Luleå tekniska universitet, Industriell miljö- och processteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-65294.

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Today there are strict demands regarding emissions to water and air from the Swedish industries. This degree project, conducted at Smurfit Kappa Piteå, will focus on the emissions of organic material in waste water from the paper mill. The overall goal was through dynamic simulations predict the Total Organic Carbon (TOC) emissions from the paper mill at the time a foreseen increase of production is implemented. The recovery boiler is currently a bottleneck in the process and the production of sulphate pulp has today its maximum capacity. This means that production growth will occur exclusively by increasing the intake of recycled fiber. The work started with a comprehensive mapping of TOC, in which ingoing pulps in pulp towers, head boxes and effluent flows were mapped. This was done over a period of two weeks and thus covered a whole production cycle. A TOC method evaluation was conducted where the most suitable analysis method was determined. Mapped data were thereupon evaluated and significant variables were identified. It was determined that use of recycled fiber was the single most important variable to TOC load from paper machine 1 (PM1), but also starch addition to paper machine 2 (PM2) was found to be significant. The work then continued with the simulation phase, consisting of two main parts. The first part consisted of preparatory work where the model was developed to be able to accurately measure TOC load to the waste water treatment plant. This part also included work to identify necessary process changes as a result of an increased production. The second part consisted of the simulation. Three different scenarios were simulated for each paper machine plus two scenarios for the recycled fiber plant. The dynamic simulation model was successively calibrated with respect to TOC concentration and trends followed the ones expected by experience. In the production increase scenario simulated, TOC load distribution between PM1, PM2 and recycled fiber plant will more evenly distributed compared to current production. The largest increase of TOC load will come from the recycled fiber plant, which according to the simulation will increase with about 30 %.
Idag ställs höga krav på de svenska industrierna vad avser utsläpp till vatten och luft. I detta examensarbete som utförts på Smurfit Kappa Piteå undersöktes avloppsflöden från pappersbruket till bioreningsanläggningen. Den övergripande målsättningen var att genom dynamiska simuleringar prediktera de TOC utsläpp pappersbruket kommer att generera efter planerad produktionsökning. Sodapannan är i dagsläget en flaskhals i processen, något som medför att produktionen av nyfibermassa idag så hög den kan vara. Detta medför att produktionsökningen uteslutande kommer att bestå av ökat intag av returfibermassa. Arbetet startade med en omfattande TOC kartering där ingående massor, inloppslådor samt avloppsflöden karterades. Detta utfördes under två veckor och täckte på så sätt en hel produktionscykel. En metodutvärdering genomfördes där lämplig metod för att mäta TOC i just de karterade provpunkterna bestämdes. Erhållna data från karteringen analyserades därpå och signifikanta variabler utvärderades. Det konstaterades att användningen av returfibermassa var den enskilt mest korrelerade variabeln till TOC nivå för pappersmaskin 1 (PM1), samt att stärkelsetillsats på pappersmaskin 2 (PM2) påvisades vara signifikant under den karterade perioden. Simuleringsfasen tog sedan vid, vilken bestod av två delar. En del bestod av förberedande arbete där modellen utvecklades för att simulera TOC halt med så god precision som möjligt. I denna del ingick även arbete för att ta fram nödvändiga processförändringar i och med den ökade produktionen. Den andra delen bestod av själva simuleringsfasen där tre olika scenarion simulerades för respektive pappersmaskin samt två stycken för returfiberanläggningen. Den dynamiska simuleringsmodellen lyckades på ett bra sätt balanseras med karterade mätdata. De utförda simuleringarna av TOC belastning till bioreningen påvisade rimliga resultat och följde de trender som erfarenhetsmässigt kan förklaras. Vid den simulerade produktionsökningen scenariot kommer TOC fördelningen mellan PM1, PM2 och returfiberanläggningen vara mer jämnt fördelat. Den största ökningen av TOC belastning kommer från returfiberanläggningen som enligt simuleringen kommer att öka med omkring 30 %.

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Gustafsson, Jesper, and Mikael Landberg. "Production of bio-plastic materials from apple pomace : A new application for the waste material." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-21216.

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Extensive quantities of apple pomace are generated annually but disposal of this waste is still much disputed. In EU alone, 500 000 tons are produced every year. Without further treatment, the acidic character of apples with their high sugar and low protein content makes the pomace unsuitable for landfilling and animal feedstock. However, further treatment is usually not economically feasible. This study addresses this issue by introducing a new approach for the apple pomace to produce sustainable materials. The high content of sugars in apple pomace which can be reshaped and reformed at higher temperatures makes the waste material suitable for plastic production. Other components found in apple pomace are 5 % proteins and 1.5 % fats. Fibers are abundant, dietary fibers amounts for more than half (55 %) the original apple pomace weight. Phenols, sorbitol and acids can be found in minor mount, 2 % or less. The apple pomace itself is a mixture of mostly pulp and peel which corresponds to 9/10 of the total mass. Whereas seeds, seed core and stalk are the remaining 1/10. The possibilities of utilizing apple pomace to produce biofilms and 3D shapes have been investigated. The effects of introducing orange pomace, another waste material produced in extensive quantities, to apple pomace samples has also been studied. Two methods were used to produce bioplastic materials; solution casting and compression molding. Glycerol was used as a plasticizer. Apple pomace, either washed or not washed, was oven-dried and milled into a fine powder. Using compression molding, plates or cups of the two powders with different amounts of glycerol were prepared. Mixtures of apple pomace and orange pomace, with or without glycerol, were prepared in the same way. The apple pomace was also used in a film casting method to produce plastic films. Applying laser cutting to the plates and plastic films, dog-bone specimens were created whose mechanical properties were analysed using a universal testing machine. Highest values in terms of tensile strength and elongation at max was reached with bioplastics produced from solution casting where the values varied in the range 3.3 – 16 MPa and 11 – 55 % respectively. The compression molding approach resulted in tensile strength values in the range 0.94 – 5.9 MPa whereas the elongation at max was in the range 0.30 – 1.9 %. A possible application for this material could be disposable tableware which does not require high mechanical strength. It was shown that it is possible to produce 3D structures and plastic films from apple pomace. Washed apple pomace with glycerol has similar properties as not washed apple pomace without the plasticizer. Adding orange pomace to apple pomace samples increases the tensile strength at the expense of the elongation at max. The pressing conditions and powder size greatly effects the mechanical properties, where a larger powder size lower the values for the mechanical properties. This new approach paves the way for a new utilization of apple pomace to replace some petroleum-based materials and at the same time solve the disposal problem of apple pomace.

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Ojoawo, Babatunde I. "Large Scale Production of Hydrogen Via Steam Reforming of Waste Plastic Pyrolysis Gas." Youngstown State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1596125244460537.

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Maru, Biniam Taddele. "Sustainable production of hydrogen and chemical commodities from biodiesel waste crude glycerol and cellulose by biological and catalytic processes." Doctoral thesis, Universitat Rovira i Virgili, 2013. http://hdl.handle.net/10803/129175.

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El hidrógeno tiene un gran potencial como combustible limpio y "verde" del futuro. En consecuencia, en esta tesis se ha investigado el desarrollo de una producción sostenible de hidrógeno y otros productos químicos a través del estudio de: 1) El comportamiento fermentativo de microorganismos anaerobios productores de hidrógeno a partir de glicerol puro y glicerol bruto contenido en el biodiesel; 2) Lainmovilización de los microorganismos en una superficie de soporte sólido; 3) La integraciónde la fermentación oscura con la hidrólisis catalítica de celulosa. Los resultados fueron los siguientes: i) Las recién aisladas bacterias Enterobacter SPH1 y Citrobacterfreundii H3 pueden fermentar el glicerol y producir niveles óptimos de H2; ii) La bacteria hipertermófilaThermotogamaritima DSM3109 puede crecer en glicerol puro y crudo; iii) El Co-cultivo (1:1) de Enterobacter SPH1 y E. coli CECT432 es capaz de producir cantidades significativas de H2 a partir de glicerol en bruto; iv) La inmovilización de los microorganismos en soportes y la adición de especies de hierro mejora la conversión de glicerol y producción de H2; i) Enterobacter SPH1 y Citrobacterfreundii H3 fueron capaces de producir H2 a partir de la fracción soluble en agua obtenida directamente de la hidrólisis de celulosa catalizada por ZrO2. Estos nuevos hallazgos mejoran nuestra comprensión de la producción microbiana de hidrógeno, y se espera que en el futuro conduzcan a la producción sostenible a partir de glicerol crudo y celulosa.
Hydrogen has a significant potential as clean and ‘green’ fuel of the future. Accordingly, this thesis investigated how to generate a sustainable production of hydrogen and other chemical commodities through study of: 1) Fermentative behavior of anaerobichydrogen producing microorganisms from pure glycerol and biodiesel waste crude glycerol; 2) The advantage of using a solid supportimmobilisationof microorganisms 3) The integration of the dark fermentative system with the catalytic hydrolysis of cellulose. The findings were: i) Newly isolated bacteria Enterobacter spH1 and Citrobacterfreundii H3 can use glycerol and produce optimal levels of H2 ii) The hyperthermophileThermotogamaritima DSM 3109 can grow on both pure and crude glycerol; iii) Co-culture (1:1) of Enterobacter spH1 and E. coli CECT432is able to produce significant amount H2 from crude glycerol; iv) Microorganisms immobilisation on supports and addition of ironspecies enhance the glycerol conversion and H2 production; v) Enterobacter spH1 and Citrobacterfreundii H3 were able to produce H2 of water soluble fractionfrom the catalytic hydrolysis of cellulose by ZrO2 material. These new findings improve our understanding of hydrogen production, and hopefully lead to sustainable production from crude glycerol and cellulose in the future.

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Rosenblum, James S. "The Relationships of Pathogenic Microbes, Chemical Parameters, and Biogas Production During Anaerobic Digestion of Manure-based Biosolids." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1376929611.

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King, Rebecca Lynne. "Investigation of Anode Catalysts and Alternative Electrolytes for Stable Hydrogen Production from Urea Solutions." Ohio University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1275514221.

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17

Xiao, Suo. "Phagotrophic Algae Based Approaches for Advanced Wastewater Treatment." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1542368310384856.

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18

Семенов, Евгений Александрович. "Технология очистки промышленных жидких отходов в алмазном производстве." Thesis, НТУ "ХПИ", 2005. http://repository.kpi.kharkov.ua/handle/KhPI-Press/29569.

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Диссертация на соискание ученой степени кандидата технических наук по специальности 05.17.01 – технология неорганических веществ. – Национальный технический университет "Харьковский политехнический институт", Харьков, 2005. Диссертация посвящена разработке технологии очистки сточных вод алмазного производства от солей марганца и никеля с получением ликвидных химических продуктов. Проведены теоретические термодинамические исследования по изучению взаимодействия компонентов отходов с различными восстановителями и окислителями, также проведена оценка термодинамической вероятности протекания твердофазных реакций между компонентами отходов. Изучено и установлено влияние на процессы осаждения в случае присутствия одного из металлов в растворе, и при их одновременном присутствии, которые содержат 1-60 г/л и 0,76-40 г/л марганца и никеля соответственно, технологических параметров: концентрации реагентов, температуры, времени осаждения. Для существующего производства синтетических алмазов предложена технологическая схема очистки сточных вод, содержащих соединения марганца и никеля, с двумя способами утилизации водно-солевого раствора: электродиализ с получением раствора NaClO и водорода или направлением в водооборотную систему предприятия.
The thesis for a candidate’s degree of technical science by specialty 05.17.01 – technology of inorganic substances. – National technical university "Kharkov polytechnic institute", Kharkiv, 2005. The dissertation is devoted to development of technology of clearing of wastewater of diamond manufacture from salts of manganese and nickel, which allows receiving products liquid on the chemical market. In the dissertation, the thermodynamic researches on study of interaction of components wastes with various reducezers and oxidizers: HCOOH, HCOH, H₂, CH₄, CO, KMnO₄, (NH₄)₂S₂O₈, K₂Cr₂O₇, NaClO, FeCl₃, Cl₂, O₃, O₂, H₂O₂ are carried out. The researches on study of influence of various parameters on process precipitation of compounds manganese and nickel from solutions, which are, contained compound out of metals and at a solution by connections of compounds of two metals: concentration reagents, temperature of time precipitation. Are established chemises of processes precipitation, as for precipitation from solutions in which there is one of metals, and from solutions in which is present as compounds of manganese and nickel. Based on received given and established the mechanism offers mathematical models of processes precipitation of compounds manganese and nickel from solutions, which are taking into account influence of concentration reagents, temperature and time of precipitation. The circuit of principle technological on clearing wastewater of containing compounds of manganese and nickel, with various ways of recycling of a formed water-salt solution is offered. As a result of the carried out technical-economic account was established, that the most effective variant is the direction of a water-salt solution in water circle system of the plant.

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Бондаренко, Тамара Степановна. "Исследования возможности использования отходов химического производства для защиты литейных форм." Thesis, НТУ "ХПИ", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/25320.

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Созданы новые составы покрытий на основе отходов производства для защиты изложниц при разливке стали сифоном и сверху, характеризующиеся высокими показателями физико-механических свойств, эффективно защищающие рабочую поверхность изложниц от агрессивного воздействия стали и газов, обеспечивающие улучшение санитарно-гигиенические условия труда.
Created new coating compositions based waste products for the protection of molds for casting steel trap and above, characterized by high levels of physical and mechanical properties, effectively protects the work surface from aggressive mold steel and gas, providing improved sanitary conditions.

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ARCANJO, JUNIOR Hélio Gomes. "Avaliação quantitativa e qualitativa do resíduo de variedades de milho cultivados para a produção de minimilho." Universidade Federal Rural de Pernambuco, 2014. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6492.

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Submitted by Mario BC (mario@bc.ufrpe.br) on 2017-02-21T13:47:37Z No. of bitstreams: 1 Helio Gomes Arcanjo Junior.pdf: 943075 bytes, checksum: a2b879ed967c57e40067c04cd29fde6a (MD5)
Made available in DSpace on 2017-02-21T13:47:37Z (GMT). No. of bitstreams: 1 Helio Gomes Arcanjo Junior.pdf: 943075 bytes, checksum: a2b879ed967c57e40067c04cd29fde6a (MD5) Previous issue date: 2014-02-24
Corn [Zea mays (L.) Poaceae] is one of the most widely produced crops in the world, with high nutritional value and diverse applications, serving as a food source for both humans and animals. The production of mini-corn increases the yield and accelerates the return of the producer’s investment. The cultivation of mini-corn generates waste from other parts of the plants, such as the stem and leaves, which are often discarded and serve as green fertilizer for the next crop. However, these parts of the mini-corn plant may serve as food for ruminants. It is therefore necessary to evaluate the remains of mini-corn plants after the harvesting of the corn. The aim of the present study was to evaluate the bromatological characteristics and in vitro digestibility of corn plants after the harvest of five varieties of mini-corn. A randomized, block design was used with a 5 X 2 factor scheme in subdivided plots with five varieties (AG 1051, Alagoano, Branquinha, São Luíz and Viçosence) with and without the harvesting of cobs in a subplot with three blocks. The Alagoano and Viçosence varieties had the highest crude protein content in the subplot without cobs. The AG1051, Branquinha and Viçosence varieties had the highest total digestible nutrients in the subplot without cobs (P > 0.05) and demonstrated the greatest fodder potential among the varieties tested. The Alagoano variety had the highest neutral detergent fiber and in vitro digestibility of neutral detergent fiber in the subplot without cobs (P > 0.05).
O milho [Zea mays (L.) Poaceae] é uma das culturas mais produzidas no mundo, possuindo alto valor nutritivo e diversas aplicações, servindo tanto na alimentação humana quanto para a alimentação animal. A produção do minimilho aumenta a rentabilidade e a velocidade do retorno do investimento ao produtor. Entretanto o cultivo do minimilho gera resíduos, tais como a planta de milho composta por palha (caule e folha) onde muitas vezes esta é desprezada servindo de adubo verde para a próxima cultura. No entanto a palha do minimilho pode servir de alimento para os ruminantes, portanto, faz-se necessário à avaliação das plantas remanescentes a colheita do minimilho. Objetivou-se neste trabalho avaliar as características químicas bromatológica e a digestibilidade in vitro de plantas integras de milho e de plantas remanescentes a colheita de minimilho de cinco variedades de milho. O delineamento foi em blocos casualizados em esquema fatorial 5x2 em parcelas sub divididas sendo, cinco cultivares na parcela (AG 1051, Alagoano, Branquinha, São Luíz e Viçosence) e com e sem colheita do minimilho na sub parcela com três blocos Dentre as variedades selecionadas as que obtiveram maiores valores para PB na sub parcela sem espiga foram as cultivares Alagoano e Viçosence. Para a variável NDT na sub parcela sem espiga as variedades que obtiveram valores superiores (P<0,05) foram o AG1051, a Branquinha e o Viçosence obtendo estes, maior potencial forrageiro diante as outras cultivares. Nas variáveis de FDN e DIVFDN na sub parcela sem espiga a variedade que obteve maiores valores (P>0,05) foi o Alagoano.

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21

Estejab, Ali. "Mathematical and Molecular Modeling of Ammonia Electrolysis with Experimental Validation." Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1514834805432007.

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22

Bonnin, Egilda Purusha. "Electrolysis of Ammonia Effluents: A Remediation Process with Co-generation of Hydrogen." Ohio : Ohio University, 2006. http://www.ohiolink.edu/etd/view.cgi?ohiou1156435340.

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23

Voigt, Paul George. "Bioethanol production from waste paper through fungal biotechnology." Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1013447.

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Bioethanol is likely to be a large contributor to the fuel sector of industry in the near future. Current research trends are geared towards utilizing food crops as substrate for bioethanol fermentation; however, this is the source of much controversy. Utilizing food crops for fuel purposes is anticipated to cause massive food shortages worldwide. Cellulose is the most abundant renewable resource on earth and is subject to a wide array of scientific study in order to utilize the glucose contained within it. Waste paper has a high degree of cellulose associated with it, which makes it an ideal target for cellulose biotechnology with the ultimate end goal of bioethanol production. This study focussed on producing the necessary enzymes to hydrolyse the cellulose found in waste paper and using the sugars produced to produce ethanol. The effects of various printing inks had on the production of sugars and the total envirorunental impact of the effluents produced during the production line were also examined. It was found that the fungus Trichoderma longibrachiatum DSM 769 grown in Mandel's medium with waste newspaper as the sole carbon source at 28 °C for 6 days produced extracellular cellulase enzymes with an activity of 0.203 ± 0.009 FPU.ml⁻¹, significantly higher activity as compared to other paper sources. This extracellular cellulase was used to hydrolyse waste newspaper and office paper, with office paper yielding the highest degree of sugar production with an end concentration of 5.80 ± 0.19 g/1 at 40 °C. Analysis by HPLC showed that although glucose was the major product at 4.35 ± 0.12 g/1, cellobiose was also produced in appreciable amounts (1.97 ± 0.71 g/1). The sugar solution was used as a substrate for Saccharomyces cerevisiae DSM 1333 and ethanol was produced at a level of 1.79 ± 0.26 g/1, the presence of which was confirmed by a 600 MHz NMR spectrum. It was found that cellobiose was not fermented by this strain of S. cerevisiae. Certain components of inks (the PAHs phenanthrene and naphthalene) were found to have a slight inhibitory effect (approximately 15% decrease) on the cellulase enzymes at very high concentrations (approximately 600 μg/1 in aqueous medium), while anthracene had no effect. Whole newsprint ink was shown not to sorb glucose. The environmental analysis of the effluents produced showed that in order for the effluents to be discharged into an aqueous ecosystem they would have to be diluted up to 200 times. They were also shown to have the potential to cause severe machinery damage if reused without proper treatment.

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24

Muhammad, Chika. "Pyrolysis-catalysis of plastic wastes for production of liquid fuels and chemicals." Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/12142/.

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The use of pyrolysis as a waste disposal method for waste plastics has been well established. However, the market value of the recycled plastic products and separate upgrading of the pyrolysis product liquid are some of the challenges facing the process. Therefore, the use of pyrolysis-catalysis of waste plastic in a two-stage pyrolysis-catalysis reactor system could bring a balance between sustainability and market value of the products generated. Hence, this work investigated the influence of different types of zeolite catalysts on the pyrolysis-catalytic upgrading of waste plastics for quality liquid fuels and valuable chemical production. Initially, two zeolite Y and ZSM-5 catalysts, in the form of pellets, were used for pyrolysis-catalysis of WEEE. Zeolite catalyst with a lower Si-Al ratio (Y zeolite) produced a higher conversion of the styrene to other aromatic products, particularly benzene and toluene. Thereafter, the influence of six zeolite catalysts with different surface areas and Si: Al ratios was investigated on the catalytic pyrolysis of waste high-density polyethylene (HDPE). Overall, the results suggest that the catalyst properties influenced the conversion of HDPE to more valuable products such as fuel-range hydrocarbons and chemicals. Similarly, pyrolysis of real-world mixed plastics, simulated mixed plastic (SMP), and virgin plastics were investigated in the presence of HZSM-5 catalyst. In addition, a sample of spent FCC catalyst was also tested for the pyrolysis of the plastic samples. Finally, the influence of spent FCC, fresh zeolite Y and ZSM-5 catalysts was investigated under different bed temperatures from 400 – 600 °C. This final work confirmed that the choice of a bed tempetrure of 500 °C, for most of this research was appropriately justified. Overall, the product oils gave fuel properties similar to gasoline, the aromatic content of the oil make them suitable as chemical feedstocks, the gas products with very high-calorific values can be used as fuel gas.

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25

Beereddy, Dinesh Reddy. "Waste Water Treatment and Optimal Utilization for Irrigation and Biogas Production." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171842.

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This paper is about the studies carried out to analyze the feasibility of using an innovative treatment system in the primary treatment process for municipal waste water. Furthermore, experiments are conducted to analyze the optimal parameters for utilizing the treated waters for irrigation purposes and for biogas production from the recovered sludge. The work is carried on the incoming municipal wastewater from Hammarby locality with around 30,000 inhabitants. Chemicals used in this process are, a metal salt namely polymerized aluminum chloride (PAX XL36) and two flocculation chemicals namely, a high molecular weight polymer (HM) (SNF Nordfloc C-192) and a low molecular weight polymer (LM) (Purfix 120). The choice of these chemicals was based on the recommendations made by previous studies on flocculation chemicals. These chemicals aid in flock formation and the DAF unit which provides compressed air, aids in flock flotation. The study is focused on optimizing parameters which implies minimal usage of chemicals and aimed to attain maximum sludge production with best possible treated water quality. All the experiments have been carried out on a pilot scale unit, designed with required specifications and with the foresight to scale up into a large scale unit based on the results. These are obtained by performing a series of analysis specifically formulated for this study. In laboratory experiments were carried out to analyze COD (chemical oxygen demand), Ammonium, Nitrate, Total nitrogen and phosphorus using Dr. Lange cuvettes. As the prime focus is on reuse of the treated water for irrigation purpose and biogas production, all the parameters are modulated in accordance with the standard water quality prescriptions for the water to be used for irrigation. In accordance with the climatic conditions of the region, various parameters are modulated in such a way that in summers the outcome water quality is emphasized and maximization of sludge/organic matter is emphasized during winter season.

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26

Parvez, Ashak Mahmud. "A study of CO2 gasification of solid carbonaceous wastes for CO2 mitigation and chemical production." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/43267/.

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This study focuses on the utilization of solid carbonaceous wastes, the mitigation of CO2 and the development of CO2-based chemical production process which is divided into three main parts. The first part consists of the investigation of solid carbonaceous samples behaviours under pyrolysis and combustion processes. The second part covers experimental study of CO2 gasification aiming at the identification of interactions during co-gasification. Here, the presence of interactions will be further discussed, particularly in terms of increasing the gasification rate of low reactive carbonaceous sample and the effect of pyrolysis heating methods on gasification reactivity. The last part considers the thermodynamic assessment of conventional and CO2-enhanced biomass gasification. The objective is to identify the influence of CO2 as a gasifying agent in biomass gasification. Moreover, the comparisons study of bio-DME production based on conventional and CO2-enhanced gasification was also carried out in this thesis. (i) Pyrolysis of NMPCBS and combustion of solid carbonaceous materials This part consists of investigation of solid carbonaceous samples behaviours under pyrolysis and combustion processes. The objective is to explore the feasibility of the utilization of non-metallic part of waste printed circuit boards (NMPCB), including the thermal behaviours of NMPCB and its blends with two types of coals by using a thermogravimetric analyser (TGA). For individual sample, the results showed that the NMPCB had the fastest rate of pyrolysis and the highest maximum weight loss rate compared with coals, thus, the highest reactivity. These were attributed to the thermal degradation properties of the constituent elements in NMPCB. Meanwhile, based on kinetic study, it is evident that the lower heating rates favoured the pyrolysis process. For blends, it was revealed that there was 6%-7% deviation in terms of the yield of solid residue between experimental and calculated values, indicating a significant gap between the overall activation energy (Ea) of the blends and its average (Eave). Thus, it confirmed the existence of interactions in co-pyrolysis. Moreover, the combustion characteristics of an Australian coal, a suite of solid carbonaceous materials, and their blends were also investigated. A drop in both ignition temperature and burnout temperature was observed when carbonaceous wastes were blended with coal at different proportions (10 wt% and 30 wt%) which justified that there were strong interactions during the co-processing of coal with carbonaceous materials. The ignition index values of coal/polystyrene and coal/oat straw blends increased by 78% and 52%, respectively, when the blending ratio increased from 10 wt% to 30 wt%. Similarly, 2.6 times increase in combustion index was also observed in coal/oat straw blend. The presence of interactions in blends was further measured by using the root mean square interaction index (RMSII) which showed that coal/oat straw and coal/polystyrene blends had the highest RMSII values. This indicated the presence of strong interactions during co-combustion. (ii) CO2 gasification of solid carbonaceous materials The second part covers the feasibility evaluation of using CO2 as a gasifying agent, namely CO2 gasification, for various solid carbonaceous materials. The work includes the conversion of carbonaceous materials to syngas, gasification characteristics of coal, a set of waste carbonaceous materials, and their blends. The experiments were run by using a thermogravimetric analyser (TGA). The results showed that CO2 gasification of polystyrene completed at 470 °C, which was lower than those of other carbonaceous materials. This behaviour was attributed to the high volatile content coupled with its unique thermal degradation properties. Further results demonstrated that CO2 co-gasification process was enhanced as a direct consequence of interactions between coal and carbonaceous materials in the blends. The intensity and temperature of occurrence of these interactions were influenced by the chemical properties and composition of the carbonaceous materials in the blends. The strongest interactions were observed in coal/polystyrene blend at the devolatilisation stage, as indicated by the highest value of RMSII, whereas at char gasification stage, the highest interactions were found in coal/oat straw blend. The catalytic effect of alkali metals and other minerals in oat straw, such as CaO, K2O, and Fe2O3, contributed to these strong interactions, thus, the addition of polystyrene and oat straw enhanced the overall CO2 gasification of coal. On the other hand, interactions between petroleum coke and solid carbonaceous materials were also analysed with the aim of enhancing the gasification reactivity of highly unreactive petroleum coke. To achieve this, an Australian coal and gum wood were chosen for co-processing with petroleum coke. The addition of gum wood was found as the significant contributor of the enhanced gasification reactivity of petroleum coke. This is due to the combined influence of a number of unique features of bio-char, such as high surface area, more active sites, low crystalline index and the catalytic effect of alkali and alkaline earth metals (AAEM) compounds. These results confirmed that proper selection of solid carbonaceous materials for gasification of petroleum coke is an effective means to improve the conversion efficiency of petroleum coke, i.e., higher reactivity, and therefore expand its large scale utilization. In addition to coal and petroleum coke, the isothermal and non-isothermal CO2 gasification of an algal biomass (Chlorella) char were also carried out by using TGA under two different heating systems, i.e. conventional and microwave-assisted pyrolysis. Based on reactivity index, maximum peak temperature and maximum mass loss rate parameters, it was shown that microwave char had higher gasification reactivity than that of conventional char. Likewise, the activation energy value of microwave char also confirmed its higher reactivity which was found to be about 9.6% lower than that of conventional char. In addition, the physical properties of these chars, such as Brunauer-Emmett-Teller surface area, carbon crystalline structure and number of active sites, were systematically tested. Based on these properties, microwave char was found to be more reactive as demonstrated by its large BET surface area, low crystalline index and high active sites. Meanwhile, co-gasification experiments under isothermal condition revealed the existence of greater synergistic effects in coal char/microwave algae char blend than that present in coal char/conventional algae char blend. (iii) Process modelling and simulation The last part considers the process simulation of thermodynamic assessment for CO2-enhanced biomass gasification. The primary objective is to identify the influence of CO2 as a gasifying agent in biomass gasification. In this part, steam and CO2-enhanced gasification of rice straw was simulated using Aspen Plus simulator and compared in terms of energy, exergy and environmental impacts. It was found that the addition of CO2 had less impact on syngas yield than gasification temperature; the cold gas efficiency (CGE) increased with CO2/Biomass ratio. At lower ratios (below 0.25), gasification system efficiency (GSE) was below 22.1%, which is lower than that of conventional gasification. However, when CO2/Biomass ratio was increased, the GSE continued to increase and reached a peak of 58.8% at ratio of 0.87. In terms of syngas exergy, the value generally increases with CO2 addition mainly due to the increase in physical exergy. In this work, chemical exergy was found to be 2.05 to 4.85 times higher than physical exergy. The maximum exergy efficiency occurred within the temperature range of 800 oC to 900 oC, related to the peak of syngas exergy. For CO2-enhanced gasification, exergy efficiency was found to be more sensitive to temperature than CO2/Biomass ratios. In addition, the preliminary environmental analysis showed that CO2-enhanced gasification resulted in significant environmental benefits compared with stream gasification. However improved assessment methodologies are needed to better evaluate the advantages of CO2 utilization.

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27

Davis, Jake Ryan. "Production of Expendable Reagents from Raw Waters and Industrial Wastes." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/344216.

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A couple of processes for electrosynthetic production of expendable reagents, namely acids, bases, and oxidants, from the native salt content of raw waters and industrial wastes were investigated, and the composition of mixed acids and bases made of sodium sulfate or sodium chloride salts were predicted using a model predicated on conservation principles, mass action relations, and Pitzer equations. Electrodialysis with bipolar membranes (BMED) was used to produce acids and bases in a single pass. Product concentration was limited only by the salt content of the feed water. The current efficiency for acid production was slightly higher than that for base, but neither dropped below 75%. Acid and base current utilization showed the same trends with respect to feed salt content and flow velocity, with higher efficiency at higher feed salt concentrations and flow velocities. Operating the BMED stack near the limiting current density of the bipolar membrane (BLCD) or above the limiting current density of the diluate compartment (LCD) decreased current efficiency and increased electrical power dissipation. Electrodialytic acid and base production was approximately10 times cheaper than the chemicals' f.o.b. unit costs as quoted on Alibaba.com. The mechanism and cost of on site peroxodisulfuric acid production by electrolysis of sulfuric acid solutions with boron doped diamond film anodes was investigated experimentally and with molecular dynamics (MD) and density functional theory (DFT) simulations. The cost of on site peroxodisulfate production was approximately 4 times less expensive than purchasing a 25 lb bag. It was shown that direct discharge of sulfate species produces sulfate radicals, which subsequently combined to form peroxodisulfuric acid. The likely hood of these reactions was dependent on electrode surface condition. Sulfate radicals could also be produced in solution by reaction with hydroxyl radicals generated by water discharge.

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Bílek, Vlastimil. "Alkalicky aktivované systémy." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-319676.

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This doctoral thesis is focused on the possibilities of alkali-activated slag (AAS) shrinkage reduction, which would together with the use of waste sludge from waterglass production contribute to wider practical utilization of this interesting material. Besides the influence on AAS dimensional changes also effect of various factors on workability, setting time and mechanical properties was investigated. Obtained results were supported by the application of instrumental techniques like izotermal calorimetry, mercury intrusion porosimetry, scanning electron microscopy and X-ray diffraction. The results show the possibilities of reduction of AAS drying shrinkage related to its cracking tendency through the combination of increased dose of waterglass and reduced water to slag ratio (w/b), partial replacement of slag by pulverized fly ash or cement by-pass dust and application of organic admixtures, where significant effect on AAS hydration was observed. On the basis of the obtained results concrete mixtures, where the whole activator was replaced by the waste sludge form waterglass production, were designed and optimized in terms of shrinkage, mechanical properties and price. Selected concretes were also tested in semi-operating conditions.

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29

Vu, Xuan Hoan, Sura Nguyen, Thanh Tung Dang, Udo Armbruster, and Andreas Martin. "Production of renewable biofuels and chemicals by processing bio-feedstock in conventional petroleum refineries." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-190806.

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The influence of catalyst characteristics, i.e., acidity and porosity on the product distribution in the cracking of triglyceride-rich biomass under fluid catalytic cracking (FCC) conditions is reported. It has found that the degradation degree of triglyceride molecules is strongly dependent on the catalysts’ acidity. The higher density of acid sites enhances the conversion of triglycerides to lighter products such as gaseous products and gasoline-range hydrocarbons. The formation of gasolinerange aromatics and light olefins (propene and ethene) is favored in the medium pore channel of H-ZSM-5. On the other hand, heavier olefins such as gasoline-range and C4 olefins are formed preferentially in the large pore structure of zeolite Y based FCC catalyst (Midas-BSR). With both catalysts, triglyceride molecules are mainly converted to a mixture of hydrocarbons, which can be used as liquid fuels and platform chemicals. Hence, the utilization of the existing FCC units in conventional petroleum refineries for processing of triglyceride based feedstock, in particular waste cooking oil may open the way for production of renewable liquid fuels and chemicals in the near future
Bài báo trình bày kết quả nghiên cứu khả năng tích hợp sản xuất nhiên liệu sinh học và hóa phẩm từ nguồn nguyên liệu tái tạo sinh khối giầu triglyceride bằng công nghệ cracking xúc tác tấng sôi (FCC) trong nhà máy lọc dầu. Kết quả nghiên cứu cho thấy xúc tác có ảnh hưởng mạnh đến hiệu quả chuyển hóa triglyceride thành hydrocarbon. Tính acid của xúc tác càng mạnh thì độ chuyển hóa càng cao và thu được nhiều sản phẩm nhẹ hơn như xăng và các olefin nhẹ. Xúc tác vi mao quản trung bình như H-ZSM-5 có độ chọn lọc cao với hợp chất vòng thơm thuộc phân đoạn xăng và olefin nhẹ như propylen và ethylen. Với kích thước vi mao quản lớn, xúc tác công nghiệp FCC dựa trên zeolite Y ưu tiên hình thành C4 olefins và các olefin trong phân đoạn xăng. Ở điều kiện phản ứng của quá trình FCC, triglyceride chuyển hóa hiệu quả thành hydrocarbon mà có thể sử dụng làm xăng sinh học cho động cơ và olefin nhẹ làm nguyên liệu cho tổng hợp hóa dầu

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Vu, Xuan Hoan, Sura Nguyen, Thanh Tung Dang, Udo Armbruster, and Andreas Martin. "Production of renewable biofuels and chemicals by processing bio-feedstock in conventional petroleum refineries." Technische Universität Dresden, 2014. https://tud.qucosa.de/id/qucosa%3A29110.

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The influence of catalyst characteristics, i.e., acidity and porosity on the product distribution in the cracking of triglyceride-rich biomass under fluid catalytic cracking (FCC) conditions is reported. It has found that the degradation degree of triglyceride molecules is strongly dependent on the catalysts’ acidity. The higher density of acid sites enhances the conversion of triglycerides to lighter products such as gaseous products and gasoline-range hydrocarbons. The formation of gasolinerange aromatics and light olefins (propene and ethene) is favored in the medium pore channel of H-ZSM-5. On the other hand, heavier olefins such as gasoline-range and C4 olefins are formed preferentially in the large pore structure of zeolite Y based FCC catalyst (Midas-BSR). With both catalysts, triglyceride molecules are mainly converted to a mixture of hydrocarbons, which can be used as liquid fuels and platform chemicals. Hence, the utilization of the existing FCC units in conventional petroleum refineries for processing of triglyceride based feedstock, in particular waste cooking oil may open the way for production of renewable liquid fuels and chemicals in the near future.
Bài báo trình bày kết quả nghiên cứu khả năng tích hợp sản xuất nhiên liệu sinh học và hóa phẩm từ nguồn nguyên liệu tái tạo sinh khối giầu triglyceride bằng công nghệ cracking xúc tác tấng sôi (FCC) trong nhà máy lọc dầu. Kết quả nghiên cứu cho thấy xúc tác có ảnh hưởng mạnh đến hiệu quả chuyển hóa triglyceride thành hydrocarbon. Tính acid của xúc tác càng mạnh thì độ chuyển hóa càng cao và thu được nhiều sản phẩm nhẹ hơn như xăng và các olefin nhẹ. Xúc tác vi mao quản trung bình như H-ZSM-5 có độ chọn lọc cao với hợp chất vòng thơm thuộc phân đoạn xăng và olefin nhẹ như propylen và ethylen. Với kích thước vi mao quản lớn, xúc tác công nghiệp FCC dựa trên zeolite Y ưu tiên hình thành C4 olefins và các olefin trong phân đoạn xăng. Ở điều kiện phản ứng của quá trình FCC, triglyceride chuyển hóa hiệu quả thành hydrocarbon mà có thể sử dụng làm xăng sinh học cho động cơ và olefin nhẹ làm nguyên liệu cho tổng hợp hóa dầu.

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Bonnet, Marie-Claude. "Contribution à l'étude de la valorisation des déchets lignocellulosiques par ozonation." Poitiers, 1988. http://www.theses.fr/1988POIT2261.

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Deng, Fu-yin, and 鄧福尹. "Enzymatic hydrolysis and chemical esterification production of biodiesel from from waste cooking oil." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/31432110109723126172.

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碩士
大同大學
生物工程學系(所)
101
The production of biodiesel usually uses expensive vegetable oils as raw material. Although waste cooking oil (WCO) is inexpensive, it generally contains high content of free fatty acids, which may lead to saponification with alkaline catalyst. In this study, Candida rugosa lipase (CRL) was adsorbed onto Diaion HP-20 resin, and then the immobilized CRL was used in the hydrolysis of WCO to fatty acid (FA), followed by the production of biodiesel through esterification using ion-exchange resin Amberlyst 15 as a catalyst. The effects of pH, concentration of lipase and reaction time on the adsorption of CRL, and those of temperature, dosage of immobilized CRL and agitation speed on the hydrolysis of WCO were examined. Response surface methodology was employed to obtain the optimal conditions for the hydrolysis of WCO: 39.26 ℃, 999.29 mg of immobilized CRL and 199.96 rpm of agitation speed; the experimental conversion of FA was 102.9 ± 1.1%, and the conversion and content of biodiesel after esterification were 95.3 ± 1.3% and 94.1 ± 0.1%, respectively. The conversion of FA remained the same after the immobilized CRL was reused for seven reaction recycles. The conversion of FA showed little decrease after immobilized CRL was stored at 4℃ or room temperature for 20 days, demonstrating the immobilized CRL has good storage stability.

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"Cotton textile mill waste: mushroom production, ensilage and alterations in chemical composition and ruminal degradability." Tese, BIBLIOTECA CENTRAL DA UFLA, 2003. http://bibtede.ufla.br/tede//tde_busca/arquivo.php?codArquivo=485.

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Jaria, Guilaine Marques. "Production of waste-based adsorbents for the removal of pharmaceuticals from water: chemical activation and modification." Doctoral thesis, 2020. http://hdl.handle.net/10773/30466.

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The sustainable development of society implies the adoption of strategies related to waste management and valorization (in a circular economy perspective) and to effluent treatment (namely for the removal of pharmaceuticals from water). Being adsorption by activated carbon (AC) a well-established method for water treatment, this work focuses on the production of AC using residues, namely sludge from pulp and paper industry, for the removal of pharmaceuticals from water. This approach aims to foster an integrated solution for the two environmental issues involved in this work. Primary pulp and paper mill sludge (PS) showed a great potential to produce carbon-based adsorbents, relatively to biological sludge (BS). Through the use of PS and a production process involving chemical activation and pyrolysis, it was possible to produce AC in both powdered and granular (using a binder agent) forms, with high surface areas (SBET) (similar to those of commercial AC with the same granulometry). The produced powdered AC presented, in batch adsorption systems, adsorption capacities for the pharmaceuticals carbamazepine (CBZ), sulfamethoxazole (SMX) and paroxetine (PAR), in the same magnitude of commercial AC. However, when applied in wastewater matrix, variations in the adsorption capacity of the produced AC for the studied pharmaceutical was observed, namely in the case of SMX, which decreased, and PAR, that increased. The produced granular AC showed, in batch adsorption systems, lower adsorption capacity for the three pharmaceuticals CBZ, SMX, and PAR, than the commercial granular AC used as reference. Also, in this case, a reduction in the adsorption capacity for CBZ and SMX was observed for wastewater matrices. In fixed-bed column studies (continuous mode) the produced granular AC presented a higher breakthrough volume and adsorption capacity for CBZ for the lower flow-rate. Also, it was observed a reduction of the adsorption capacity with the increase of the complexity of the aqueous matrix (distilled water > wastewater > multicomponente solutions – with the three pharmaceuticals – in wastewater). The application of different functionalization methods to the powdered AC surface showed to be an interesting approach, evidencing an increase in the selectivity of some functionalized AC for some of the pharmaceuticals under study, despite the general reduction in their SBET. Concluding, this work demonstrates the potential of PS from pulp and paper mill industry to produce alternative AC, particularly in the powdered form, to be applied in the removal of pharmaceuticals from water.
O desenvolvimento sustentável da sociedade implica a adoção de estratégias ligadas à gestão dos resíduos e sua valorização (numa perspetiva de economia circular) e ao tratamento de efluentes (nomeadamente, para a remoção de fármacos da água). Sendo o processo de adsorção por carvão ativado (CA) um método bem estabelecido para o tratamento de águas, este trabalho incide sobre a produção de CA a partir de resíduos, nomeadamente lamas da indústria da pasta e do papel, para a remoção de fármacos da água. Esta abordagem pretende proporcionar uma solução integrada nos dois desafios ambientais anteriormente referidos. Comparativamente com as lamas biológicas (LB), as lamas primárias (LP) da indústria da pasta e do papel, mostraram ter um grande potencial para a produção de adsorventes à base de carvão. A partir de LP, e usando um processo de ativação química e pirólise, foi possível produzir CA, quer na forma de pó, quer na forma granular (usando um agente aglomerante) com elevadas áreas superficiais (SBET) (comparáveis às de CA comerciais da mesma granulometria). Os CA produzidos em pó apresentaram, em sistemas descontínuos de adsorção, capacidades de adsorção para os fármacos carbamazepina (CBZ), sulfametoxazol (SMX) e paroxetina (PAR), da mesma ordem de grandeza que os CA comerciais. Contudo, quando aplicados em matrizes de efluente real, observam-se variações na capacidade de adsorção dos CA produzidos para os fármacos em estudo, principalmente no caso do SMX, que diminuiu, e da PAR, que aumentou. O CA granular produzido apresentou, em sistemas descontínuos de adsorção, menor capacidade de adsorção para os três fármacos CBZ, SMX e PAR, do que o CA granular comercial de referência. Também neste caso, se verificou uma redução da capacidade de adsorção da CBZ e do SMX em matrizes de efluente real. Estudos realizados em colunas de leito-fixo (modo contínuo) mostraram que o CA granular produzido apresentou maior volume de rutura e maior capacidade de adsorção da CBZ para o menor fluxo. Verificou-se, ainda, a redução da capacidade de adsorção com o aumento da complexidade da matriz aquosa (água destilada > efluente real > soluções multicomponente - com os três fármacos - em efluente). A aplicação de diferentes metodologias de modificação ou funcionalização da superfície dos CA em pó mostrou ser uma abordagem interessante, observando-se um aumento de seletividade de alguns CA funcionalizados para alguns dos fármacos em estudo, apesar da redução geral da SBET destes. Em suma, este trabalho demonstra o potencial das LP da indústria papeleira para a produção de CA alternativos aos CA comerciais, em particular para a formulação em pó, e para a sua aplicação na remoção de fármacos das águas.
Programa Doutoral em Química

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35

Dias, Sandra Raquel da Silva. "Production of activated carbons by microwave pyrolysis of industrial wastes for the removal of pharmaceuticals from water." Master's thesis, 2018. http://hdl.handle.net/10773/24698.

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The presence of pharmaceuticals in water bodies, being biologically active compounds, have raised concerns due to the adverse effects in non-target organisms. With the conventional treatments, applied in the wastewater treatment plants (WWTPs), being inefficient for the removal of these contaminants, WWTPs are pointed out as the main source of pharmaceuticals into the environment. The use of adsorption, as an advanced treatment for the removal of pharmaceuticals from water, in particular by using activated carbons (ACs), has shown to be an easy-handling and cost-efficient process, without sub-products formation. Since the production of ACs can be an expensive process, due to the high energy requirements and the use of expensive precursors, the alternative microwave (MW) pyrolysis of paper mill primary sludge (PS) can be a promising solution, contributing simultaneously for industrial waste valorisation. In the scope of this work, ACs were produced by MW pyrolysis of PS impregnated in KOH (activating agent) for 10 min at 800 W, washed with hydrochloric acid and sieved to obtain the fraction of particles with a size up to 180 μm. Different ACs were obtained by changing activating agent:precursor ratios, namely 0.5:1, 1:1 and 1.5:1. The produced ACs were physico-chemically characterised. In order to assess the performance of the produced ACs, batch adsorption experiments were performed with ultra-pure water to determine the adsorption percentages of the anti-epileptic carbamazepine (CBZ). The effect of AC dosage and the effect of contact time were also tested. The obtained results have shown that, overall, the ACs produced with an activating agent:precursor ratio of 0.5:1 presented specific surface areas (SBET) between 773 and 1190 m2/g and high percentages of CBZ removed from ultra-pure water solutions, above 80 %, for AC dosages of 0.1 g/L and a contact time of 24 h. The lab-made ACs have shown a more developed porous structure than the reference commercial AC and comparable SBET. Nevertheless, under the same experimental conditions, different production batches resulted in ACs with different properties and performances, highlighting that further research work is required to optimise its production process, making it repeatable.
Sendo os fármacos compostos biologicamente ativos, a sua presença nos recursos hídricos tem gerado preocupações devido aos efeitos adversos em organismos não-alvo. Sendo os tratamentos convencionais, aplicados nas estações de tratamento de águas residuais (ETARs), ineficientes para a remoção destes contaminantes, as ETARs são apontadas como a principal fonte de fármacos no meio ambiente. O processo de adsorção, enquanto tratamento avançado para a remoção de fármacos da água, em particular com o uso de carvões ativados (CAs), tem-se mostrado um processo de fácil aplicação e eficiente, sem formação de subprodutos. Como a produção de CAs pode ser um processo dispendioso, devido aos requisitos energéticos e ao uso de precursores de elevado custo, a alternativa pirólise em micro-ondas (MO) de lama primária (LP) da indústria papeleira pode ser uma solução promissora, contribuindo simultaneamente para a valorização de resíduos industriais. Neste trabalho, os CAs foram produzidos por pirólise em MO de LP impregnada com KOH (agente ativante) durante 10 min a 800 W, lavados com ácido clorídrico e crivados para obtenção da fração de partículas com dimensão inferior ou igual a 180 μm. Obtiveram-se diferentes CAs alterando as razões de agente ativante:precursor, nomeadamente 0.5:1, 1:1 e 1.5:1. Os CAs produzidos foram física e quimicamente caraterizados. No sentido de avaliar o desempenho dos CAs produzidos, realizaram-se testes de adsorção em descontínuo com água ultra-pura para determinar a percentagem de adsorção do anti-epilético carbamazepina (CBZ). O efeito da concentração de CA e o efeito do tempo de contacto também foram testados. Os resultados obtidos demonstraram que, de um modo geral, os CAs produzidos numa razão de 0.5:1 de agente ativante:precursor apresentaram áreas superficiais específicas (SBET) entre 773 e 1190 m2/g e elevadas percentagens de remoção de CBZ de soluções de água ultra-pura, acima de 80 %, para concentrações de CA de 0.1 g/L e tempos de contacto de 24 h. Os CAs produzidos em laboratório demonstraram ter uma estrutura porosa mais desenvolvida do que o CA comercial de referência e SBET comparáveis. Todavia, para as mesmas condições experimentais, diferentes lotes de produção originaram CAs com propriedades e desempenhos diferentes, denotando que mais trabalho de investigação deve ser investido de modo a otimizar o seu processo de produção, tornando-o repetível.
Mestrado em Estudos Ambientais

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Ledwaba, Kabelo Mike. "Development of a microbial fuel cell for energy recovery from wastewater." Diss., 2017. http://hdl.handle.net/10500/24742.

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A key engineering challenge is a transition to cleaner sustainable energy supply that is derived from renewable resources. Furthermore, affordable access to this modern sustainable energy services for communities in particular poor rural and urban communities is crucial. Microbial fuel cell (MFCs) is an emerging renewable alternative technology with potential to be self-sustaining that could alleviate the energy crisis and reduce environmental pollution. The use of the MFC as a dual system for electricity generation and wastewater treatment is been well reported in literature. Manganese dioxide (MnO2) is an effective electro-catalyst that have been used for alkaline fuel cells and battery application. MnO2 have a high conductivity and high structural porosity for ion and gas transport. In addition, MnO2 have a favourable crystal morphology, which makes it particularly useful for improving oxygen reduction reaction in the fuel cell. Graphene (GO) will be loaded on MnO2 surface as an effective support material. GO is a material good for electrical conductivity and their mechanical strength is applicable in electro-catalytic activities and is cost effective. In this work, a constructed dual chamber MFC configuration with graphite rod electrodes, MnO2-GO electrocatalyst and proton exchange membrane (PEM) using municipal sewage wastewater to generate electricity. The MnO2 as an alternative electro catalyst used for oxygen reduction reaction (ORR) in the MFC while using reduced graphene (rGO) as a support to enhance electrode surface area. Also addressing the effect of graphene material loading on MnOx catalyst for electrochemistry. The characterization of the MnO2-GO electrocatalyst have been analysed using X-Ray diffraction (XRD), Brunau-Emmett-Teller (BET) surface area and Fourier transform infrared spectroscopy (FTIR) for structural properties. Electrochemical techniques such as cyclic voltammetry (CV) for MnO2-GO electrocatalyst. Thermal gravimetric analysis (TGA) for the thermal properties, and the morphological properties probed by Scanning Electron Microscopy (SEM). The dual chamber MFC design functioned successfully and tested for energy generation from municipality sewage wastewater. The maximum voltage of 586 mV reached during MFC operation with various sewage municipal wastewater COD of 100-300mg/L. The maximum power density of 248 mW/m2 with resistance of 16.98 Ω and highest current density of 1.72mA/m2 was observed at the first cycle as compare to other cycle. The lowest value of 0.002159 mA/m2 obtained at the end of 10 days. The content of municipality sewage wastewater is capable of generating electricity. The physico-chemical properties of α-MnO2 exhibits excellent cycling stability on the electrochemical. This excellent cycling stability of α-MnO2 as a super capacitor electrode material. In addition, the graphene material loading on α-MnO2 has improved the electro catalytic activity, which influences the kinetics of the reduction reaction. The α-MnO2 synthesized BET analysis specific surface area of 134.61m2 g-1 reported. MFC technology has the potential to finds its own niche in the energy industry as it is becoming more and more sustainable due to the lower cost of electro catalyst materials. Power densities of 248 mW/m2 using wastewater with COD of 291mg/l were much higher than those previously obtained using low strength wastewater. These results have opened doors for further investigation of improving electro catalysis, utilized high concentration wastewater with high COD and improved MFC design including electrode materials.
Civil and Chemical Engineering
M. Tech. (Chemical Engineering)

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37

Mahlangu, Jethro Padya. "Guidelines for successful implementation of total productive maintenance in a chemical plant / Jethro Padya Mahlangu." Thesis, 2014. http://hdl.handle.net/10394/15382.

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With the world economy becoming unpredictable, it has become a necessity for businesses to relook at the way they do business. The world has become competitive and companies that aim to become profitable have seen the need to find ways to improve efficiencies and increase productivity to stay relevant. There has been an adoption of strategies that are aimed at improving the efficiencies in companies such as Total Productive Maintenance (TPM). The strategy is aimed at improving equipment efficiencies and increase productivity through the transfer of certain skills from maintenance personnel to operators. The aim is that the operators perform some of the activities that the maintenance people used to do and they do the more complex tasks. By transferring these skills to operators there is constant cleaning, inspections and lubricating of equipment. This frees up time for maintenance people to do planning and other jobs that require time and higher skills levels. The implementation of these activities allows companies to tap into unused capacity that was always hidden by breakdowns and unplanned stops. The process however requires commitment from management and all stakeholders involved in the organisation. There are prescribed implementation processes that can be followed or companies can follow their own processes but the fundamentals of involving people from the onset must be followed. The involvement of stakeholders creates commitment at all levels and in order to sustain this initiative people must be committed to it. The inclusion of the activities transferred from maintenance people to operators, will reinforce the knowledge and habits required from operators and perhaps sustain the initiative.
MBA, North-West University, Potchefstroom Campus, 2015

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Costa, Emanuel Tiago Pinto Monteiro da. "Evaluation of alternative feedstocks for bioenergy production in Portugal: non-edible oilseed crops, by-products and wastes." Tese, 2020. https://hdl.handle.net/10216/131663.

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Costa, Emanuel Tiago Pinto Monteiro da. "Evaluation of alternative feedstocks for bioenergy production in Portugal: non-edible oilseed crops, by-products and wastes." Doctoral thesis, 2020. https://hdl.handle.net/10216/131663.

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40

Li, Minsheng. "Life-cycle inventory (LCI) development for a solid waste/coal blend gasification system for production of power and chemicals." 2002. http://www.lib.ncsu.edu/theses/available/etd-07072002-163217/unrestricted/etd.pdf.

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Dissertations / Theses on the topic 'Waste chemical production'

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