Academic literature on the topic 'Ethylene glycol – Environmental aspects'

There is a global trend to replace the production of conventional recyclable plastics with biobased ones, allowing a sustainable alternative adapted to the current concept of a circular bioeconomy. Forest-industrial and agricultural biomass wastes (lignocellulosic biomass waste, LCBW) produce severe problems in some developing countries because they are improperly disposed of or burned in the open air. Such wastes are attractive as a raw material to produce bioplastics due to their low cost. Furthermore, low-pollution processes can complete an economical and environmentally friendly approach. This review focuses on bio-polyethylene furanoate (PEF) production from LCBW as an alternative for polyethylene terephthalate (PET), one of the most widely used fossil-based plastic. The standpoint is based on the replacement of fossil-based monomers for the manufacture of PET, terephthalic acid (TPA), and ethylene glycol by two bio-based monomers, namely 2,5-furandicarboxylic acid (FDCA) and bio-ethylene glycol (Bio-MEG). This study describes the processes to obtain each bio-monomer, as well as the resulting polymers’ performance aspects, biodegradability, environmental and economic considerations, and recycling.

Recycling and reusing of poly (ethylene terephthalate) (PET) fabrics waste are essential for reducing serious waste of resources and environmental pollution caused by low utilization rate. The liquid-phase polymerization method has advantages of short process flow, low energy consumption, and low production cost. However, unlike prepolymer, the material characteristics of PET fabrics waste (complex composition, high intrinsic viscosity, and large quality fluctuations) make its recycling a technique challenge. In this study, the falling film-rotating disk combined reactor is proposed, and the continuous liquid-phase polymerization is modeled by optimizing and correcting existing models for the final stage of PET polymerization to improve the product quality in plant production. Through modeling and simulation, the weight analysis of indexes closely related to the product quality (intrinsic viscosity, carboxyl end group concentration, and diethylene glycol content) was investigated to optimize the production process in order to obtain the desired polymer properties and meet specific product material characteristics. The model could be applied to other PET wastes (e.g., bottles and films) and extended to investigate different aspects of the recycling process.

The article describes the results of a study to determine the simultaneous effect of polyethylene terephthalate waste (PET) and polyethylene (PE) on the strength characteristics and bulk density of epoxy mortars. In these mortars, 9 wt.% of the polymer binder was replaced by glycolysate which was made from PET waste and propylene glycol. Additionally, 0–10 vol.% of the aggregate was substituted with PE agglomerate made from plastic bags waste, respectively. The modification of the composition of epoxy mortar has a special environmental and economic aspect. It also allows to protect natural sources of the aggregate, while reducing the amount of waste and reducing problems arising from the need to store them. The resulting composite has very good strength properties. With the substitution of 9 wt.% of resin and 5 vol.% of sand, a flexural strength of 35.7 MPa and a compressive strength of 101.1 MPa was obtained. The results of the microstructure study of the obtained mortars constitute a significant part of the paper.

The awareness of occupational health risk management in the electronics industry is weak in China, and many Chinese occupational health management regulations have not been effectively implemented. China’s current occupational hazards classification method and the Environmental Protection Agency (EPA) inhalation risk assessment model recognized internationally were used to perform health risk assessments for a chip manufacturing company in the electronics industry in order to determine the existing problems and put forward the optimization proposals of the occupational hazards classification method in China. The results showed that the detected concentrations of toxic and harmful chemicals in all testing points did not exceed the occupational health exposure limits in China. According to the EPA inhalation risk assessment model, the highest values of non-carcinogenic risks of ammonia, chlorine, fluoride, sulfuric acid, hydrogen chloride, ethylene glycol, phosphine, boron trifluoride, isopropanol, benzene, and xylene were 5.10, 67.12, 1.71, 45.98, 1.83, 1.43, 160.35, 46.56, 2.52, 5.55, and 5.37, respectively, which means workers in electronic chip manufacturing companies exposed to these chemicals have higher occupational health risks. However, on the basis of the occupational hazards classification method, the occupational health risks of exposure to the toxic and hazardous chemicals are relatively harmless operations. The evaluation results of the EPA inhalation risk assessment model are generally higher than those of the occupational hazards classification method. It’s recommended to refine the value of occupational exposure limit B, taking more characteristics of the hazard factors into account and fuzzifying the parameters to optimize the occupational hazards classification method. At the same time, it is suggested that the electronic chip manufacturing company should conduct anti-virus risk management covering in three aspects: increasing the awareness of occupational hazards, enhancing system ventilation, and improving personal health management measures.

The novel aspect of this research is the fabrication, characterisation, and application of an engineered adsorbent made from quartz sand coated with calcium ferric oxides (QS/CFO) derived from the wastepaper sludge ash (WPSA) for the removal of tetracycline (TC) from synthetic water. Initially, the new adsorbent was fabricated using a Ca/Fe molar ratio, sand/FeCl3 ratio, pH (of synthesising environment), ethylene glycol dose, and temperature of 1:0.75, 1:1, 12, 6 mL/100 mL, and 95℃, respectively. Then, the new adsorbent was applied to treat water having 50 mg/L of TC in batch experiments, taking into account the effects of the contact time (0–180 min), pH of water (2–12), the dose of adsorbent (0.05–0.5 g), and agitation speed (0–250 rpm). The results obtained proved the engineered adsorbent can remove as much as 90% of the TC (adsorption capacity of 21.96 mg/g) within 180 min at an initial pH, adsorbent dosage, and agitation speed of 7, 0.3g per 50 mL, and 200 rpm, respectively. It was also found that the pseudo-second-order model describes the kinetic measurements better than the pseudo-first-order model, which indicates that the TC molecules have been bonded with the prepared sorbent through chemical forces. Furthermore, the intra-particle diffusion model results demonstrated that the diffusion mechanism plays a significant role in TC adsorption; however, it was not the predominant one. Finally, the outcomes of the characterisation analysis proved that the newly formed layer on the quartz sand substantially contributed to the removal of the TC from the contaminated water.

Potentially fatal ethylene glycol intoxication in an adult with normal renal function was treated with 4-methylpyrazole administered three hours after the incident occurred. The plasma ethylene glycol concentration was 3.5 g 1-1 on admission. The metabolic acidosis present on admission resolved within four hours, and the subsequent clinical course was uneventful. The apparent plasma half-life of ethylene glycol was 16 h and the mean renal and plasma clearances of ethylene glycol were 24 and 25 ml min-1, respectively. These results support the hypothesis that complete blockade of hepatic metabolism of ethylene glycol is achieved by 4-methylpyrazole. The only side-effect observed as a result of treatment was a transient slight increase in serum transaminase activity.

Laboratory results are presented for a patient who died following ingestion of an antifreeze solution containing ethylene glycol. It was observed that the measurement of osmolality, which is of value in the early stages of ethylene glycol poisoning, may give normal results if there are many hours delay between ingestion and admission. The hypocalcaemia which frequently accompanies ethylene glycol poisoning is shown to develop over several hours.

Ligament/tendon tissue engineering has the potential to provide therapies that overcome the limitations of incomplete natural healing responses and inadequate graft materials. While ligament/tendon fibroblasts are an obvious choice of cell type for these applications, difficulties associated with finding a suitable cell source have limited their utility. Mesenchymal stem cells/marrow stromal cells (MSCs) are seen as a viable alternative since they can be harvested through routine medical procedures and can be differentiated toward a ligament/tendon fibroblast lineage. Further study is needed to create an optimal biomaterial/biomechanical environment for ligament/tendon fibroblastic differentiation of MSCs. The overall goal of this dissertation was to improve the understanding of the role that biomechanical stimulation and the biomaterial environment play, both independently and combined, on human MSC (hMSC) differentiation toward a ligament/tendon fibroblast phenotype. Specifically, the effects of cyclic tensile stimuli were studied in a biomaterial environment that provided controlled presentation of biological moieties. The influence of an enzymatically-degradable biomaterial environment on hMSC differentiation was investigated by creating biomaterials containing enzymatically-cleavable moieties. The role that preculture may play in tensile responses of hMSCs was also explored. Together, these studies provided insights into the contributions of the biomaterial and biomechanical environment to hMSC differentiation toward a ligament/tendon fibroblast phenotype.

The inevitable fate of much of the ethylene glycol used for deicing bridges, aircraft and airport runways, and from leaking and overheating automobile radiators is as runoff to adjacent surface waters which commonly contain higher plants, including members of the duckweed family, the Lemnaceae. However, ethylene glycol is usually thought of as being a relatively benign pollutant and therefore its effects on higher plants have received little attention. The EC50 for ethylene glycol with respect to the inhibition of frond reproduction in axenically-grown Lemna gibba is 176 mM. HPLC and GC/MS studies indicate that ethylene glycol is not metabolized by duckweed. However, after having grown in the presence of ethylene glycol, the fronds of L. gibba are a darker green, translucent color, tend to sink, and generated gas bubbles in their growth media. It is hypothesized that these effects are due to a disruption by ethylene glycol of the pectin layer between cells as evidenced by the appearance of intercellular gaps in the aerenchymatous tissues. Other polyols, including propylene glycol and glycerol, produced the same effects as ethylene glycol. The result of the creation of the intercellular gaps is to increase the uptake of solutes and water from the growth media into the intercellular air spaces. The enhanced uptake of water caused the fronds to sink as well as change the optical properties which resulted in the darker green appearance. The enhanced uptake of nutrients led to the stimulation of growth at concentrations of ethylene glycol below 80 mM. The enhanced uptake of sucrose led to enhanced metabolism and an increased evolution of carbon dioxide as reflected by the bubbles in the growth media. However, the enhanced uptake of organic and inorganic pollutants led to their enhanced toxicities. Therefore, though ethylene glycol may be of relatively low direct toxicity, it can through various interactions, potentiate the toxicities of other pollutants
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Lemna gibba was used as a model aquatic angiosperm to study the effects of ethylene glycol. Ethylene glycol, usually thought of as a benign pollutant, was shown to cause a phenomenon that was termed the polyol effect. Poly(ethylene glycol)s with carbon chain lengths of less than 34 residues, as well as two ethers of ethylene glycol, also elicited the polyol effect Although ethylene glycol was not extremely toxic (acute toxicities in the mM rather than muM or nM range), it interacted synergistically with other organic chemicals to tentiate their toxicities. Thus, the toxicity of naphthalene was enhanced in the presence of ethylene glycol but, due to the volatility of naphthalene, experiments to demonstrate that ethylene glycol also enhanced the metabolism of naphthalene were inconclusive A spectroradiometric method was devised to quantify the polyol effect. The threshold concentration of ethylene glycol at which the polyol effect could be detected by this method was between 35 and 40 mM. The earliest developmental time for the detection of ethylene glycol stress was between the second and third generation of daughter fronds. The spectroradiometric methods that were developed for measuring ethylene glycol stress were shown to be considerably more sensitive and reproducible than any other available method. Spectroradiometry, using the duckweeds as bioindicators, could provide a relatively quick, sensitive monitoring technique for aquatic pollution of various kinds The toxicities of thorium and cadmium were not potentiated by ethylene glycol and neither were their uptakes. Both control and ethylene glycol-grown fronds absorbed thorium. Only a small portion of the absorbed thorium was leachable indicating that thorium uptake was either a result of active cellular uptake or binding to external cell surfaces. However, thorium absorption by dead L. gibba fronds was equally fast showing that uptake was a result of biosorption rather than active cell processes. DRIFTS analysis of thorium-loaded fronds revealed that thorium was bonded to carboxylic sites. Sugar cane bagasse was also able to remove thorium from an aqueous medium suggesting that plant materials in general could be highly effective absorbents for the remediation of actinide pollution
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Les nanotechnologies appliquées aux sciences pharmaceutiques ont pour but d’améliorer l’administration de molécules actives par l’intermédiaire de transporteurs nanométriques. Parmi les différents types de véhicules proposés pour atteindre ce but, on retrouve les nanoparticules polymériques (NP) constituées de copolymères “en bloc”. Ces copolymères permettent à la fois l’encapsulation de molécules actives et confèrent à la particule certaines propriétés de surface (dont l’hydrophilicité) nécessaires à ses interactions avec les milieux biologiques. L’architecture retenue pour ces copolymères est une structure constituée le plus fréquemment de blocs hydrophiles de poly(éthylène glycol) (PEG) associés de façon linéaire à des blocs hydrophobes de type polyesters. Le PEG est le polymère de choix pour conférer une couronne hydrophile aux NPs et son l’efficacité est directement liée à son organisation et sa densité de surface. Néanmoins, malgré les succès limités en clinique de ces copolymères linéaires, peu de travaux se sont attardés à explorer les effets sur la structure des NPs d’architectures alternatives, tels que les copolymères en peigne ou en brosse. Durant ce travail, plusieurs stratégies ont été mises au point pour la synthèse de copolymères en peigne, possédant un squelette polymérique polyesters-co-éther et des chaines de PEG liées sur les groupes pendants disponibles (groupement hydroxyle ou alcyne). Dans la première partie de ce travail, des réactions d’estérification par acylation et de couplage sur des groupes pendants alcool ont permis le greffage de chaîne de PEG. Cette méthode génère des copolymères en peigne (PEG-g-PLA) possédant de 5 à 50% en poids de PEG, en faisant varier le nombre de chaînes branchées sur un squelette de poly(lactique) (PLA). Les propriétés structurales des NPs produites ont été étudiées par DLS, mesure de charge et MET. Une transition critique se situant autour de 15% de PEG (poids/poids) est observée avec un changement de morphologie, d’une particule solide à une particule molle (“nanoagrégat polymére”). La méthode de greffage ainsi que l’addition probable de chaine de PEG en bout de chaîne principale semblent également avoir un rôle dans les changements observés. L’organisation des chaînes de PEG-g-PLA à la surface a été étudiée par RMN et XPS, méthodes permettant de quantifier la densité de surface en chaînes de PEG. Ainsi deux propriétés clés que sont la résistance à l’agrégation en conditions saline ainsi que la résistance à la liaison aux protéines (étudiée par isothermes d’adsorption et microcalorimétrie) ont été reliées à la densité de surface de PEG et à l’architecture des polymères. Dans une seconde partie de ce travail, le greffage des chaînes de PEG a été réalisé de façon directe par cyclo-adition catalysée par le cuivre de mPEG-N3 sur les groupes pendants alcyne. Cette nouvelle stratégie a été pensée dans le but de comprendre la contribution possible des chaines de PEG greffées à l’extrémité de la chaine de PLA. Cette librairie de PEG-g-PLA, en plus d’être composée de PEG-g-PLA avec différentes densités de greffage, comporte des PEG-g-PLA avec des PEG de différent poids moléculaire (750, 2000 et 5000). Les chaines de PEG sont seulement greffées sur les groupes pendants. Les NPs ont été produites par différentes méthodes de nanoprécipitation, incluant la nanoprécipitation « flash » et une méthode en microfluidique. Plusieurs variables de formulation telles que la concentration du polymère et la vitesse de mélange ont été étudiées afin d’observer leur effet sur les caractéristiques structurales et de surface des NPs. Les tailles et les potentiels de charges sont peu affectés par le contenu en PEG (% poids/poids) et la longueur des chaînes de PEG. Les images de MET montrent des objets sphériques solides et l'on n’observe pas d’objets de type agrégat polymériques, malgré des contenus en PEG comparable à la première bibliothèque de polymère. Une explication possible est l’absence sur ces copolymères en peigne de chaine de PEG greffée en bout de la chaîne principale. Comme attendu, les tailles diminuent avec la concentration du polymère dans la phase organique et avec la diminution du temps de mélange des deux phases, pour les différentes méthodes de préparation. Finalement, la densité de surface des chaînes de PEG a été quantifiée par RMN du proton et XPS et ne dépendent pas de la méthode de préparation. Dans la troisième partie de ce travail, nous avons étudié le rôle de l’architecture du polymère sur les propriétés d’encapsulation et de libération de la curcumine. La curcumine a été choisie comme modèle dans le but de développer une plateforme de livraison de molécules actives pour traiter les maladies du système nerveux central impliquant le stress oxydatif. Les NPs chargées en curcumine, montrent la même transition de taille et de morphologie lorsque le contenu en PEG dépasse 15% (poids/poids). Le taux de chargement en molécule active, l’efficacité de changement et les cinétiques de libérations ainsi que les coefficients de diffusion de la curcumine montrent une dépendance à l’architecture des polymères. Les NPs ne présentent pas de toxicité et n’induisent pas de stress oxydatif lorsque testés in vitro sur une lignée cellulaire neuronale. En revanche, les NPs chargées en curcumine préviennent le stress oxydatif induit dans ces cellules neuronales. La magnitude de cet effet est reliée à l’architecture du polymère et à l’organisation de la NP. En résumé, ce travail a permis de mettre en évidence quelques propriétés intéressantes des copolymères en peigne et la relation intime entre l’architecture des polymères et les propriétés physico-chimiques des NPs. De plus les résultats obtenus permettent de proposer de nouvelles approches pour le design des nanotransporteurs polymériques de molécules actives.
The goal set to nanotechnologies applied to pharmaceutical sciences is to improve drug delivery and benefits with the help of nanometer-sized vehicles. At this time different types of drug carriers had been proposed. Amongst them, block copolymer nanoparticles (NP) have been designed to allow, at the same time, efficient drug encapsulation and provide surface properties (hydrophilic layer) to the NP which are necessary for its interactions with biological systems by preventing the opsonisation and the subsequent recognition by the mononuclear macrophage system (MPS) and the rapid elimination of the drug carrier. The most prominent polymer architecture in drug delivery application is the linear di-block copolymer architecture, such as poly(ethylene glycol) blocks (PEG) linked to a polyester hydrophobic chain. PEG is the gold standard to add a hydrophilic corona to drug carrier’s surface, but its efficacy is directly linked to its surface organization and surface densities. In spite of limited success of diblock at the clinical stage, few studies have been devoted to other type of architecture such as comb-like copolymers, either for the exploration of new synthesis routes or for the characterization of particles prepared from alternative architecture polymers. We attempted in preamble of this work to define more closely the conceptual and technical framework allowing quantitative determination of PEG surface densities. This review work has been used in the experimental work to define the characterization methods. Several synthesis strategies have been developed for the preparation of comb copolymers in this work. All strategies are based on random copolymerization of dilactide with small epoxy molecules with a pendant group suitable for subsequent PEG grafting, yielding a polyester-co-ether backbone. In a second step, PEG chains have been grafted on available pendant groups (alcohol groups or alkyne) to produce the final comb copolymers. In the first part of the experimental work, esterification reaction by acylation and coupling (the Steglish reaction) allowed the preparation of a first comb-like copolymer library with PEG content varying from 5 to 50 % (w/w). The number of PEG chains (PEG grafting density) was varying while the lengths of the PEG chains and the hydrophobic PLA backbone were kept constant. The library of comb-like polymers was used to prepare nanocarriers with dense PEG brushes at their surface, stability in suspension, and resistance to protein adsorption. The structural properties of nanoparticles (NPs) produced from these polymers by a surfactant-free method were assessed by DLS, zeta potential, and TEM and were found to be controlled by the amount of PEG present in the polymers. A critical transition from a solid NP structure to a soft particle with either a “micelle-like” or “polymer nano-aggregate” structure was observed when the PEG content was between 15 to 25% w/w. This structural transition was found to have a profound impact on the size of the NPs, their surface charge, their stability in suspension in presence of salts as well as on the binding of proteins to the surface of the NPs. The arrangement of the PEG-g-PLA chains at the surface of the NPs was investigated by 1H NMR and X-ray photoelectron spectroscopy (XPS). NMR results confirmed that the PEG chains were mostly segregated at the NP surface. Moreover, XPS and NMR allowed the quantification of the PEG chain coverage density at the surface of the solid NPs. Concordance of the results between the two methods was found to be remarkable. Physical-chemical properties of the NPs such as resistance to aggregation in saline environment as well as anti-fouling efficacy, assessed by isothermal titration calorimetry (ITC), were related to the PEG surface density and ultimately to polymer architecture. In the second part of this work, grafting of PEG chains on a polyester-co-ether backbone was directly performed using cyclo-addition of PEG azide on pendant alkyne groups. The new strategy was designed to understand the contribution of PEG chains grafted on PLA backbone ends. The new polymer library was composed of PEG-g-PLA with different PEG grafting densities and PEG molecular weights (750, 2000 and 5000 D). PEG chain grafting could only take place on pendant groups with this approach. NPs were produced by different methods of nanoprecipitation, including “flash nanoprecipitation” and microfluidic technology. Some formulation variables such as polymer concentration and speed of mixing were studied in order to observe their effects on NP surface characteristics. Unlike for the first copolymer library, here the NPs size and zeta potential were found to not be much affected by the PEG content (% w/w in polymer). Sizes were also not affected by the PEG chains length. TEM images show round shaped object and as expected sizes were found to decrease with polymer concentration in the organic phase and with a decrease in mixing time of the two phases (for flash nanoprecipitation and microfluidic technology). PEG chain surface densities were assessed by quantitative 1H NMR and XPS. In the third experimental part, we explored the role of polymer architecture on drug encapsulation and release of curcumin from NPs. Curcumin has been chosen as a model with a view to develop a delivery platform to treat diseases involving oxidative stress affecting the CNS. As previously observed with blank NPs, a sharp decrease in curcumin-loaded NP size and morphology change occurred between 15 to 20 % w/w of PEG. Drug loading, Drug loading efficiency and the diffusion coefficients of curcumin in NPs are showing a dependence over the polymer architecture. NPs did not present any significant toxicity when tested in vitro on a neuronal cell line. Moreover, the ability of NPs carrying curcumin to prevent oxidative stress was evidenced and linked to polymer architecture and NPs organization. In a nutshell, our study showed the intimate relationship between the polymer architecture and the biophysical properties of the resulting NPs and sheds light on new approaches to design efficient NP-based drug carriers. The results obtained lead us to propose PEG-g-PLA comb architecture copolymers for nanomedecine development as an alternative to the predominant polyester-PEG diblock polymers.

Primary Water Stress Corrosion Cracking (PWSCC) is one of important ageing issues in PWR (Pressurized Water Reactor) primary systems. It has been pointed out that high concentration dissolved hydrogen may lead to occurrence of PWSCC. The authors have proposed to substitute hydrogen by methanol as a fundamental countermeasure of PWSCC. So far corrosion tests of stainless steels and Zircaloy-4 in methanol solutions at 320 °C were conducted under γ-ray irradiation and without irradiation. The test results show that methanol is promising. In the present paper, γ-ray irradiation experiments of methanol solution at 320 °C were done up to 100 kGy. A study on the radiolysis of methanol solution is important from two aspects. One concerns corrosion of structural materials. The radiolysis of methanol may result in formation of harmful compounds to the structural materials, such as carboxylic acids. It is necessary to know the yields of such compounds. The other concern is possible polymerization of methanol and formation of organic polymer deposit on fuel claddings. Large amount of the deposit on fuel claddings should be avoided to keep integrity of fuel claddings. Therefore, it should be clarified whether gaseous species are major products and whether polymerized species of methanol such as ethylene glycol is formed. After the γ-ray irradiation of methanol solution, following species were analyzed: CO2 and H2, methanol, formaldehyde, formate and acetate, and ethylene glycol and glycerin. Without γ-ray irradiation, the major process of the thermal decomposition of methanol at 320 °C is oxidation of methanol by water and generation of one CO2 molecule and three H2 molecules. Under γ-ray irradiation, the decomposition of methanol is accelerated; little methanol remains after 10 kGy irradiation. The major product is CO2, and polymerization of methanol unlikely occurs. After methanol is completely decomposed, the hydrogen yield still increases. The reducing environment is maintained. Probably, transient organic species play important roles. The addition of low concentration methanol may be sufficient to maintain reducing environment of the PWR primary systems.

Abstract The paper objective is to demonstrate the successful operation & maintainability of Carbon Capturing & Injection (CC&I) Project. CC&I project is one of the major Saudi Aramco projects to reduce Greahhouse Gaseous (GHG) emissions as one of the company key environmental aspects. The project is located in the Eastern Province of the Kingdom of Saudi Arabia at Hawyiah NGL Recovery Plant (HNGLP). The project started capturing the CO2 in 2015 from HNGLP Acid Gas Removal Units (AGRUs) and then inject nearly 750 Kton per year of carbon dioxide into oil wells for sequestration and enhanced oil recovery maintainability. In most of gas plants, acid gas (primarily CO2 and H2S) is treated till achieving certain air quality parameters before thermal oxidizing process. After CC&I project, acid gas (only CO2 for HNGLP) is captured inlieu of thermal oxidizing. CC&I project has several processes from CO2 capturing to injection as follows: integrally geared multistage compressor, standalone dehydration system using Tri-Ethylene Glycol (TEG), CO2 recovery system, Granulated Activated Carbon (GAC) to treat water generated from compression and dehydration systems for reuse purpose, and special dense phase pump that transfers dehydrated CO2 at supercritical phase through 85 km pipeline to one of South Ghawar Field Wells to replace typical oil recovery enhancement technique (sea water injection). CC&I project is unique as it has several new technologies and experiences represented by the compressor capacity, pumping supercritical fluid at very high pressures, using mechanical ejector application to maximize carbon recovery, and using TEG as dehydration medium with CO2. CC&I project design considered the noise hazards generated from the compressor operation via installing engineering enclosure with proper ventilation system.(1) This project helped HNGLP to minimize the total GHG emissions from combustion sources by nearly 30-35% comparing with before. It also helped to reduce nearly 75-80% of the consumed fuel gas to run the thermal oxidizers in AGRUs and send it as product as sales gas. The project helped to increase HNGLP business sustainability performance measures (less energy consumption by 8-9% and nearly 5-6% water reserves sustainability).

Abstract This paper will present corrosion management of a wet sour gas carbon steel export pipeline using continuous and batch corrosion inhibitors with mono-ethlene-glycol (MEG) as hydrate mitigation strategy in NACE MR 0175/ ISO 15156 region 3 (severe sour). The wet sour gas carbon steel export pipeline corrosion management via continuous CI and batch inhibitors with closed loop MEG regeneration system is rare worldwide. This is especially challenging when the case study may potentially be the longest wet sour gas, large diameter carbon steel pipeline (approximately 207km × 32 inch) in the world thus far. Pipeline corrosion management and hydrate management aspects when being reviewed holistically, it could provide significant cost savings yet safeguarding the overall technical integrity of the pipeline. The overall corrosion management leverages on Shell's many years of JIP and operating experience in sour service including the pipeline material specification, corrosion management, inspection, and maintenance philosophy. Reliable correlation between reservoir properties and uncertainties severe sour service, flow assurance, chemical behavirous, operating experiences etc were considered to best represent the operating envelope for this wet sour gas carbon steel pipeline. This includes the testing and selection of continuous CI and batch inhibitor, corrosion monitoring, operational pigging, maintenance, and inspection requirements throughout the field life.

Solvent wastes produced at Cernavoda NPP consist of miscellaneous acetone, toluene, methanol, chloroform, triclorethan, white spirit and ethylene glycol. These are normally LLW containing only relatively small quantities of beta/gamma emitting radionuclides and varying amounts of tritium with activity below E08Bq/l. This paper is a review of some current innovative work of Waste Management Facility from Institute for Nuclear Research Pitesti in the development of a viable solidification technology to convert solvent wastes into a stable monolithic form, which minimises the probability to release tritium in the environment during interim storage, transportation and final disposal. The paper presents the author’s research on immobilisation of solvent wastes by cementation using aluminium stearate additive. A quality assurance program should accompany the production of waste forms. The goal of all tests should be to obtain a license for a certain process from a competent authority. The process will be clean, which means there will be no secondary waste and low doses to the personnel will be achieved; the product quality will meet any National requirement and the reproducibility of the process meets any QA requirement.

In many industrial processes, cooling with brines is preferable to cooling with an evaporating refrigerant. For medium and high temperatures (above about −35°C/−30°F), aqueous solutions of calcium chloride, sodium chloride, ethylene glycol, propylene glycol, and methanol have typically been used. For very low temperatures (down to about −80°C/-110°F) halocarbon refrigerants methylene chloride and trichloroethylene have generally been used. In recent years, both methylene chloride and trichloroethylene have come under increasingly strict regulation because of their toxicity. While many plants continue to use these brines, most are searching for alternates. This study was begun in response to the needs of a plant that was replacing methylene chloride with aqueous calcium chloride. The high viscosity of the calcium chloride brine caused design and operational problems. The above-mentioned brines, as well as aqua-ammonia, polydimethylsiloxane, and d-limonene, were compared for cost, toxicity, flammability, environmental safety, and energy efficiency. The energy efficiency comparison included comparisons of heat transfer coefficient, mass flow rate, volume flow rate, frictional pressure drop, inertial pressure drop, and pumping power. The comparisons indicated that aqua-ammonia was the best choice as a replacement for methylene chloride and trichloroethylene in some temperature ranges.

Nowadays, many refineries are built close to the shorelines due to economical point of view. The operation of refineries requires the cooling system which, in many cases is based on the circulation of the water pumped from the sea into the water intake and distributed to the plants. The circulated water should be led back by a proper outfall system somewhere in the sea where the water depth is deep enough and environmental conditions are fully met. High Density Poly Ethylene (HDPE) pipes are one of the options which can be used as a proper outfall system. The bathymetry of the shoreline and coastal zone, outfall discharge, method of installation both in the sea and the shore area as well as HDPE materials and welding techniques should be considered for the selection of a proper outfall system. Fluid characteristics and hydraulic conditions are other issues which should be checked and controlled. Various loadings should be considered for the mechanical design of the pipeline in the sea. This paper attempts to highlight the main steps required to be taken for the design of an HDPE pipe in the sea. Furthermore, a design flowchart is recommended. At the end, the design of the outfall pipeline of the refineries phases 9 & 10 located in South Pars Field of Persian Gulf is discussed and the results are presented.

Abstract This project describes the modeling process to design the packaging and heat exchanger for a half-bridge wide-bandgap (WBG) power semiconductor module. The module uses two silicon carbide, metal-oxide-semiconductor field-effect transistor (MOSFET) devices per switch position that are soldered to an aluminum nitride, direct-bond copper (DBC) substrate. A baseplate cooling configuration (e.g., no thermal grease) is used along with a water-ethylene glycol, jet-impingement-style heat exchanger. The heat exchanger was designed to be fabricated using prototyping equipment from the National Renewable Energy Laboratory, complies with automotive standards (for minimal channel sizes, flow rates, and coolant), and considers reliability aspects (i.e., erosion/corrosion). Device-scale computational fluid dynamics (CFD) is used first to design the slot jet impingement cooling configuration and compute the effective heat transfer coefficient (HTC) of the concept. The computed HTCs are then used as boundary conditions for a finite element study to optimize the package geometry (e.g., device layout and baseplate thickness) to minimize thermal resistance and minimize temperature variation between the module’s four devices. Finally, a fluid manifold is designed to generate the slot jets and cool the devices. Module-scale CFD predicts a relatively low junction-to-fluid thermal resistance of 16.7 mm2·K/W, a 1.4°C temperature variation between devices, and a total pressure drop of 5,860 Pa (0.85 psi) for the design. The thermal resistance of the module design is about 67% lower than the 2015 BMW i3 power electronics/modules thermal resistance.