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Isoprene, a volatile hydrocarbon emitted largely by plants, plays an important role in regulating the climate in diverse ways, such as reacting with free radicals in the atmosphere to produce greenhouse gases and pollutants. Isoprene is both deposited and formed in soil, where it can be consumed by some soil microbes, although much remains to be understood about isoprene consumption in tropical soils. In this study, isoprene-degrading bacteria from soils associated with tropical plants were investigated by cultivation and cultivation-independent approaches. Soil samples were taken from beneath selected framework forest trees and economic crops at different seasons, and isoprene degradation in soil microcosms was measured after 96 h of incubation. Isoprene losses were 4–31% and 15–52% in soils subjected to a lower (7.2 × 105 ppbv) and a higher (7.2 × 106 ppbv) concentration of isoprene, respectively. Sequencing of 16S rRNA genes revealed that bacterial communities in soil varied significantly across plant categories (framework trees versus economic crops) and the presence of isoprene, but not with isoprene concentration or season. Eight isoprene-degrading bacterial strains were isolated from the soils and, among these, four belong to the genera Ochrobactrum, Friedmanniella, Isoptericola and Cellulosimicrobium, which have not been previously shown to degrade isoprene.

article i nfo Theaimofthisstudyistoevaluateabenchscaledirectcontactmembranedistillation(DCMD)performanceusing flatsheet polytetrafluoroethylene(PTFE)membrane atdifferent inlet flow rates, temperatures,and salinity com- position. The effect of the various operating conditions on the quality of the distillate water produced was inves- tigated by Inductively Coupled Plasma/Optical Emission Spectrometry (ICP/OES) and ion chromatography (IC). Five different feed solutions were studied such as the Arabian Gulf seawater, rejected brine from Qatari thermal desalination plants andartificialbrine.Apermeate fluxof 35.6LMH canbe producedattemperaturedifferenceof 50 °C between hot and cold sides. The thermal energy efficiency of the system was analyzed and reached up to 22%. The flow mode and turbulence promoter in feed channels were found to have a very important effect on the flux and energy efficiency. It was also noted that using spacers in the flow channels increase the distillate flux by more than 51% as compared with a spacer-free system. The investigation has shown that the highest Gain Output Ratio (GOR) value can be obtained when using less saline feed solution at the highest feed temper- ature, lowest permeate temperature and lowest flow rate. Finally, the salt rejection rate throughout the conduct- ed tests was very high (N99.9%) and almost independent of any studied operational parameters. Eventually, DCMD has proven to be a feasible and effective technology capable of consistently producing high quality distil- late from a very high salinity feed even with substantial quality difference compared to other desalination methods such as RO and MSF.

Little is currently known about the potential impact of silver nanoparticles (AgNPs) on estuarine microbial communities. The Colne estuary, UK, is susceptible to oil pollution through boat traffic, and there is the potential for AgNP exposure via effluent discharged from a sewage treatment works located in close proximity. This study examined the effects of uncapped AgNPs (uAgNPs), capped AgNPs (cAgNPs) and dissolved Ag 2 SO 4 , on hydrocarbon-degrading microbial communities in estuarine sediments. The uAgNPs, cAgNPs and Ag 2 SO 4 (up to 50 mg L −1 ) had no significant impact on hydrocarbon biodegradation (80–92% hydrocarbons were biodegraded by day 7 in all samples). Although total and active cell counts in oil-amended sediments were unaffected by silver exposure; total cell counts in non-oiled sediments decreased from 1.66 to 0.84 × 10 7 g −1 dry weight sediment (dws) with 50 mg L −1 cAgNPs and from 1.66 to 0.66 × 10 7 g −1 dws with 0.5 mg L −1 Ag 2 SO 4 by day 14. All silver-exposed sediments also underwent significant shifts in bacterial community structure, and one DGGE band corresponding to a member of Bacteroidetes was more prominent in non-oiled microcosms exposed to 50 mg L −1 Ag 2 SO 4 compared to non-silver controls. In conclusion, AgNPs do not appear to affect microbial hydrocarbon-degradation but do impact on bacterial community diversity, which may have potential implications for other important microbial-mediated processes in estuaries.

Membrane distillation (MD) is a hybrid thermal-membrane desalination process that uses low-grade waste heat and hydrophobic membrane to produce high quality distillate. The MD process can treat highly saline brines that other conventional desalination processes cannot treat. These unique features of the MD process make it an ideal candidate to desalinate concentrated brines from thermal desalination plants to augment fresh water production from existing facilities. A consortium consisting of ConocoPhillips Global Water Sustainability Center, Qatar University, and Qatar Electricity & Water Company was formed to evaluate the application of MD for the desalination of concentrated brines from thermal plants. Five different MD technologies were evaluated and the two most suitable technologies were selected for field-testing. The pilot units A & B are based on multi-effect vacuum and air gap MD technologies, respectively. These units were tested side-by-side at a full-scale thermal desalination plant in Qatar. Pilot unit A showed a stable flux of 6.2 LMH under optimized conditions with excellent salt rejection (> 99.9%). Pilot unit B achieved a distillate flux of 2.5 LMH and salt rejection greater than 98.9%. Overall, MD was shown to be a feasible technology to produce potable quality water from the brines discharged from thermal desalination plants.

An investigation into the potential of using industrial low-grade waste heat in desalination using membrane distillation (MD) has been carried out. This investigation highlighted the need to work on fresh water production using economic and environmentally friendly techniques. Using an approach based on heat integration and heat recovery principles, process streams in three industrial processes, namely the liquified natural gas (LNG), Ethylene and Vinyl Chloride Monomer (VCM) were screened to eliminate unsuitable sources of low-grade heat. This approach is appropriate to Qatar, being one of the countries that have large natural gas reserves and an emerging petrochemical industry. The criteria for selecting suitable low-grade heat sources led to the elimination of LNG and Ethylene processes for further consideration. The VCM process on the other hand showed a promising outlook, in particular in the direct chlorination section where a major vapor stream is condensed through the temperature range 11...

This work was aimed at evaluating the relative merits of bioaugmentation, biostimulation and surfactant-enhanced bioavailability of a desert soil contaminated by crude oil through biopile treatment. The results show that the desert soil required bioaugmentation and biostimulation for bioremediation of crude oil. The bioaugmented biopile system led to a total petroleum hydrocarbon (TPH) reduction of 77% over 156 days while the system with polyoxyethylene (20) sorbitan monooleate (Tween 80) gave a 56% decrease in TPH. The biostimulated system with indigenous micro-organisms gave 23% reduction in TPH. The control system gave 4% TPH reduction. The addition of Tween 80 led to a respiration rate that peaked in 48 days compared to 88 days for the bioaugmented system and respiration declined rapidly due to nitrogen depletion. The residual hydrocarbon in the biopile systems studied contained polyaromatics (PAH) in quantities that may be considered as hazardous. Nitrogen was found to be a limiting nutrient in desert soil bioremediation. United Arab Emirates University Research Sector (grant 03-7-12/02).

Background Anti-IgE (omalizumab) inhibited early and late asthmatic reactions and infiltration of inflammatory cells in asthmatic bronchial biopsies at baseline. The effect of chronic allergen exposure on these outcomes is unknown. Repeat allergen challenge in human skin represents a suitable model to address this question. Objective To study the effect of anti-IgE (omalizumab) on early-phase (EPR) and late-phase (LPR) skin reactions and cellular infiltration by using a repeat skin allergen challenge designed to imitate chronic allergen exposure. Methods Twenty-four atopic allergic volunteers received omalizumab or placebo for 12 weeks. Paired intradermal challenges of allergen (30 biological units) and diluent control were administered on 9 occasions at 2-week intervals. Early-phase and late-phase skin reactions and cellular infiltration in skin biopsies (using immunohistochemistry and in situ hybridization) were measured at intervals. Results Compared with placebo, omalizumab-treated patients had a progressive reduction in the LPR that was significantly greater than its effect on the EPR (median, −63% vs −24% respectively; P =.009). In addition, significant reduction of the LPR was reached within 2 weeks of commencing treatment, compared with 8 weeks for the EPR. There was a priming effect of repeated allergen challenge on infiltration of eosinophil, neutrophil, T H 2 (CD3 + /IL-4 + ), and total FcɛRI + cells in patients on placebo that was abrogated in those receiving omalizumab. Conclusion The more marked effect of omalizumab on the LPR and prevention of the repeat-dose priming effect on several inflammatory cell types support a role for anti-IgE treatment in conditions associated with chronic allergic inflammation.

A bioremediation of crude oil contaminated soils study was carried out in engineered laboratory biopile systems. In soil bioremediation, biopiles are ‘ex situ’ treatment systems that consist of excavated and aerated contaminated soils amended by addition of biological, mineral or organic material depending upon specific needs. When bacteria are added to the contaminated soil undergoing biological treatment, the latter is referred to as a bioaugmented treatment system. Such soils are arranged above ground in a pile fashion and hence the term biopile. The study has shown virtually identical trends in respiration rates when indigenous and commercial added bacteria where employed. However, the bioaugmented experiments yielded much greater respiration rates and lead to a reduction of 75% of the initial oil in just 118 days, compared to 1 year in similar studies in the literature. The benefits of engineered biopile systems include safe operations, facilitated material balance and process controllability. The benefits of bioaugmentation were clearly demonstrated and it was found that when no nutrients are added to the soil, bacteria tend to metabolize hydrocarbons into carbon dioxide and water rather than assimilate carbon in cell growth. Polyaromatics analysis of treated soil in this investigation pointed out that simpler and more bioavailable crude oil components were degraded first. A simple sigmoid model for the carbon dioxide generation was developed from the respiration data.

Mean voidage in packed beds of spherical, cylindrical, and nonconventional cylindrical particles has been accurately measured, and the data obtained were employed to develop predictive mean voidage correlations that were not only simpler to use and more accurate than existing correlations, but also helped in developing a single general voidage correlation incorporating a particle shape factor applicable to a variety of particle shapes. Such mean voidage correlations are highly sought in packed bed design for a multitude of applications and can also assist in minimizing pressure drop in such packed beds by guiding particle shape selection.

Mass transfer and kinetics of nitrification using free and alginate gel immobilized Nitrosomonas cells were investigated under no cell growth conditions. A simulated wastewater with industrial strength ammonia content was employed. Under the conditions employed, external diffusion limitations were negligible, but internal mass transfer was found to be very significant. The estimated effective diffusivity of oxygen in alginate gel was around 8.7 × 10 −9 m 2 s −1 for assumed first order kinetics at 25 °C. This value is somewhat lower than reported values, and the discrepancy was explained in terms of different conditions and presence of biomass in this study. The activation energy for nitrification with free Nitrosomonas cells was around 73 kJ mol −1 and compared favourably with reported values. However, the Arrhenius plot for nitrification using immobilized cells displayed a break at 20 °C, and this gave rise to two different activation energies. Between 20 and 35 °C, the activation energy was around 56 kJ mol −1 , whilst between 10 and 20 °C, the activation energy was around 163 kJ mol −1 . This result suggests that different rate limiting steps for nitrification using immobilized cells may apply according to the range of temperatures employed.

Modeling of flow and its impact on transport phenomena in packed bed systems is discussed. A detailed flow model based on an improved Brinkman equation has been derived and its solution is presented. This model incorporates a representative voidage function that enabled the generation of velocity profiles that closely followed the voidage profile and highlighted the importance of the wall zone. Two approximate flow models from the literature have been used to obtain velocity profiles for the purpose of comparison with the model derived herein. Significant differences were observed in the location and magnitude of velocity maxima predicted by the various models employed in this work. The impact of such findings on transport phenomena is discussed. A method to obtain a wall zone velocity is suggested to facilitate estimation of transport parameters near the wall.

The potential use of blank alginate beads, free (non-immobilized) live and dead and immobilized dead algal cells for the removal of nickelions from aqueous solutions was investigated. Immobilization enhanced the sorption of nickel and repetitive use of the sorbent could beachieved. Increasing initial pH or initial nickel ions concentration resulted in an increase in nickel uptake. The experimental results were fittedsatisfactory to the Langmuir and Freundlich isotherm models. The results of the kinetic studies showed that the sorption of nickel ions onblank alginate beads, free live, dead and alginate immobilized dead algal cells followed pseudo-second order kinetics.© 2003 Elsevier Ltd. All rights reserved. Keywords: Biosorption; Immobilization; Algal cells; Nickel; Isotherms 1. IntroductionToxic heavy metal contamination of industrial water is asignificant universal problem. These toxic metals can causeaccumulative poisoning, cancer and brain damage whenfound above the tolerance levels [1]. Exposure to nickelfor example, can cause dermatitis and allergic sensitization[2,3]. Many processes have been used for the removal ofheavy metals from industrial effluents. Chemical precipita-tion, coagulation, solvent extraction, membrane separation,ion exchange and adsorption are commonly applied in thetreatment of industrial effluents [4]. For dilute metal concen-trations, ion exchange, reverse osmosis and adsorption canbe applied [5]. However ion exchange and reverse osmosishave high operating cost, which makes adsorption a betteralternative for heavy metals removal. Activated carbon isone of the most recommended sorbents. However, the rela-tively high cost associated with production and regenerationof spent carbon restricts its use to wealthy nations. Thus,many low-cost sorbents have been investigated[2,3,6–25].Biosorption, which is defined as the accumulation andconcentration of pollutants from aqueous solutions by theuse of biological materials, appears to offer a technically

Temperature polarization is one of the major sources responsible for flux drop in membrane distillation systems due to the reduction in the driving force across the membrane. The present study offers a predictive model developed for the estimation of the temperature polarization coefficient across the membrane taking into consideration the simultaneous heat and mass transfer phenomena. The uniqueness of the developed model is its ability to predict the intermediate temperatures (temperatures along the flow path of the membrane sheet) which can be used to estimate the local flux and local temperature polarization coefficients as opposed to the methods used by others which estimate the TPC, using the average bulk temperatures, resulting in a tool that enables the estimation of the temperature polarization coefficient (TPC) at different operating conditions. It was found that higher feed temperatures result in higher temperature polarization effect and hence a lower TPC. It was also observed that TPC increases with feed flow rate. The highest TPC value of 0.82 was achieved for a flow rate of 3. L/min and a feed-permeate temperature system of 60-20. The use of flow promoters further enhances the performance of the DCMD system and was reflected on increasing the TPC values (0.66 for a spacer filled channel compared to 0.47 for a spacer free operation) at 1.5. L/min flow condition with 70-30 temperature system. The axially integrated local flux values predicted by the model were in good agreement with the experimentally measured fluxes. Qatar University and ConocoPhillips GWSC for their financial support of this work under grants QUST-CENG Fall 12/13-22 and QUEX-CWT-11/12-5 respectively Scopus

A case study on innovation and creativity in engineering design instruction has been presented. The novel approach emphases on the role of student engagement, team spirit and industry support to students. This paper presented findings on student engagement, engagement styles and practical implementation of instructional method to enhance student engagement in engineering design. This approach ensures that the course is more student-centered than it was before and the students assume the responsibility for their own learning. A team teaching and learning approach was used with great emphasis on industrial involvement and student role play for a better preparation for future professional life. This new approach has allowed students to reinforce and apply subject knowledge, whilst developing key skills such as teamwork and communication. The project based approach has been successful at improving students' engagement and sense of responsibility within a more active learning environment. The student engagement in experiential learning was very successful and highly valued by students themselves and local industry. The approach presented boosted students' confidence and demonstrated to them the industrial relevance of their design work, making a significant shift from the purely academic achievement to near professional life achievement.

Flowsheeting packages can be useful computational aids in process design and help in understanding the behaviour of processes. However, without quality input data and a good overall chemical engineering background, the simulation results can easily be misinterpreted. Kinetic data and thermodynamic property methods can be the most likely source of errors. A case study is presented, where the same process model of a typical vinyl chloride monomer plant can give widely differing simulation results, even when employing recommended thermodynamics property methods. In this work the PRSV thermodynamics method were used as a base case, and then in turn the extended NRTL method, the Antoine vapour pressure method and the Kabadi-Danner method. The Antoine method gave the worst predictions, with deviations as high a 293%, whilst the other two methods gave varying but still significant deviations, indicating differing sensitivity of the methods to different parts of the process. Recommendations were put forward to minimize misinterpretation of simulation results.

Abstract The gas industry in Qatar is experiencing a massive growth and its energy consumption leads to significant carbon emissions specifically Carbon Dioxide (CO2). All plant operators have been required to report carbon emissions to local authorities according to international standards. However, it is not clear how carbon will be managed in the future. In this work, a potentially attractive solution for carbon management will be put forward. This work involves a case study on Ammonia production facility and the carbon footprint of the Ammonia process. The sources of CO2 investigated were from the Ammonia process itself and its main support utilities (combustion in gas turbines, steam boilers and natural gas reformers). Refering to previous work done (on Ammonia process simulation using industry standard HYSYS and process calculation using a spreadsheet), an attempt was made to recover CO2 from the process to be utilize in Urea and Methanol manufacturing. This approach was based on the concept of plant integration where Ethylene, Ammonia, Urea, and Methanol production facilities would have a certain degree of mass integration. The work highlighted the importance of the Hydrogen balance from the Ethylene facility and the extent of CO2 recovery and capture from the Ammonia facility. The results indicated that it is possible to target around 45% of CO2 produced in Ammonia manufacturing and utilize it to produce high value products such as Urea and Methanol. It was found that when excess Hydrogen is utilizaed with part of CO2 produced from Ammonia manufacturing facility, excess Methanol that is equivalent to a half a train capacity can be produced (~1424 MTPD*). In addition to that it was found that utilizing another part of CO2 with Ammonia product - that is usually gets exported - almost one train of Urea can be produced (~3728 MTPD). The concept of plant integration was found very powerful and relevant in the context of carbon management since it is known that captured CO2 in Qatar and gulf area may not be stored underground in large quantities because the geology is mainly carbonate reservoirs. The work also indicated the need to purify both CO2 and hydrogen to qualities compatible with the applications indicated. A network of hydrogen and CO2 pipelines was also highlighted in the plant integration study. This plant integration of important petrochemical processes has shown that it is possible to reduce significantly carbon emission in Ammonia manufacturing.

Gas hold-up and oxygen transfer have been investigated in two geometrically similar external loop airlift reactors of linear scale ratio of 2. In mass transfer experiments, the sampling location was found to be important as significantly different kLa values can be obtained. The variations of kLa with probe location have been explained in terms of non-uniform hydrodynamic properties and the results obtained have been validated by means of high speed video camera recordings. At higher gas flowrates, the gas hold-up was significantly higher in the large-scale reactor. It was found that in order to maintain the gas hold-up or kLa constant in both the small- and large-scale reactor, the small-scale reactor required 25% and 27% more power input per unit volume of liquid respectively. © 1997 SCI.

A successful story on teaching innovation and creativity in engineering design instruction is presented in this paper. The approach emphasizes the role of student engagement built around team spirit and industry support to students. This paper presents findings on student engagement, engagement styles and practical implementation of instructional methods to enhance student engagement in engineering design. This approach targets student-centered learning where the students assume the responsibility for their own learning. A team teaching and learning approach was adopted with great emphasis on industrial involvement and student role play for a better preparation for future professional life. This approach has allowed students to reinforce and apply subject knowledge, whilst developing key skills such as teamwork and communication. The project-based approach has been successful at improving students' engagement and sense of responsibility within a more active learning environment. It has also boosted a majority of students' confidence in themselves, making a significant shift from the purely academic achievement to near professional life achievement.

Local mass transfer studies have been carried out in an external loop airlift reactor and indicated the existence of significant non-uniformities in aeration capacity in the various sections of the reactor. The traditional assumption of a single well mixed unit with a single kLa value for external loop airlift reactors was found to be poor and cannot represent adequately the reactor as a whole. The liquid head in the gas/liquid separator was found to have a significant negative negative effect on the local mass transfer coefficient kLa. Visualization of flow patterns showed the existence of strong vortices in the riser and downcomer which contributed to a reduction in local aeration capacity. Mass transfer experiments in an aerated tank showed that the aeration capacity can be reduced by half in viscous media but improved significantly in the presence of salts.

The structure of a series of packed beds of non-equilateral cylindrical particles has been investigated and compared with those of beds of spheres and equilateral cylinders of similar dimensions. It is found that the mean voidage of beds of equilateral cylinders is consistently lower than the corresponding values for beds of spheres and non-equilateral cylinders of aspect ratios 0.25, 0.5, 2 and 3. End effects do not appear to be present in beds of cylinders of aspect ratios of 0.25 and 0.5 and generally, both wall and end effects are significantly weaker than corresponding effects in beds of spheres and equilateral cylinders. This suggests that chanelling is reduced in beds of non-equilateral cylindrical pellets. Whilst the axial voidage distribution of beds of non-equilateral cylinders appears to be almost uniform, the radial voidage distribution bears the effect of confining walls and an oscillatory profile is observed in most cases, but is seen to be irregular for aspect ratios 0.25 and 0.5. ...

لقد تناول هذا الجزء بداية ثلاثة أبحاث وعروض تقديمية حول احتجاز الكربون باستخدام التقنيات التي يمكن أن تحل محل الإجراءات المعهودة لتنقية الأمينات (الغسل). ولعل الحافز يكمن في أن هذه الأساليب البديلة أو أشكالها المختلفة ستندرج ضمن النشاط التجاري. يطرح جيسون أورنستين ذلك بقوة. ويقتبس قول هيرزوج1: "اليوم، تعد الطريقة الوحيدة المعتمدة لاحتجاز الكربون وتخزينه هي تنقية الأمينات. في بعض الأحيان تكون هي الوسيلة الأمثل، حيث يتم من خلالها انتقاء ثاني أكسيد الكربون بجودة عالية وتزيد معدلات الاسترداد بها عن 90%...ولكنها تجعل من الصعب إجراء تعديلات تحديثية على مصانع الطاقة القديمة والأقل كفاءة. على سبيل المثال، إذا كانت كفاءة أحد المصانع 35%، سيؤدي إدخال التحديثات عليه باستخدام احتجاز الكربون وتخزينه إلى انخفاض كفاءته إلى 20-25%. مما يجعله مقترحا مكلفا للغاية."

Plant design is the capstone design course taken in the senior year of a chemical engineering students at Qatar University and is spread over two semesters (Plant Design I and Plant Design II). The course content, delivery and assessment were substantially changed and are now based on the concepts of open-ended, enquiry-guided project learning approach. This ensures that the course is more student-centered than it was before and the students assume the responsibility for their own learning. A team teaching and learning approach was used with great emphasis on industrial involvement and student role play. In the context of our design teaching experience, students act as engineering design consultants and faculty/industrial advisors act as clients for a design tender.

Global warming and climate change has been linked to green house gas emissions into the atmosphere with an overwhelming scientific evidence supported by a variety of field measurements over a period of time. CO2 has been identified as a major contributor to global warming because of its high concentration in the atmosphere. The bulk of the recent CO2 increase in concentration in the atmosphere has been attributed to industrial activities, primarily power generation using fossil fuels. The international scientific community, through the IPCC, concluded that action needs to be taken urgently to mitigate carbon emissions before the point of no return in carbon dioxide concentration in the atmosphere is reached. In that respect, carbon capture and storage (CCS) was deemed to be the most effective solution to deal with large quantities of CO2 emitted. However, recent studies have shown that whilst this may be true where adequate geological storage site are available both in capacity and quality, many parts of the world simply are not blessed with this natural facility. It is imperative to seek alternatives to underground storage. This is even more important at the present time given that no real progress was made to manage carbon emissions on a large scale despite some CCS pilot studies conducted in Algeria, Norway, Canada, Australia and USA. Our work focused on an alternative to CCS, namely carbon mineralization. This is a special form of carbon conversion that does not have the same disadvantage of energy intensity as catalytic conversion of carbon back into fuel or hydrocarbon feedstock. Our approach is based on a relatively low temperature mineralization exploiting salt in reject brines, thus potentially solving two environmental problems in one single solution. Our work is both experimental and computational and has shown that good salt and carbon conversion at around 30 C is feasible. However, computational simulation work using Excel has shown that this method cannot convert all captured CO2 because of the potentially huge amounts to be captured. Nevertheless, this method is an alternative and helps solve two environmental problems in the Arabian Gulf.

The solution to the carbon conundrum does not seem to be within reach in the short or medium term, despite significant advances and knowledge gains in demonstration scale CCS facilities. This stems from the fact that currently carbon management has no binding policies and legal framework. Without this legislation, it is unlikely that international cooperation in carbon trade and management would flourish. The situation is also exacerbated by doubts about the suitability of sites and global capacity to store captured CO 2 . Sophisticated cost models have been developed for carbon capture and storage, and these indicate that cost reduction in the complete carbon value chain should be focused on the capture phase as this is the most energy intensive. However, there are uncertainties about properly costing carbon storage as this should involve search for suitable site location costs. The GCC states have characteristics that make them one of the largest consumers of fresh water and energy in the world, and by default emitters of CO 2 per capita. There are currently no demonstration or commercial scale CCS facilities in the GCC and in the short term, it is unlikely to be the case given that current carbon capture technologies favor coal rather than natural gas as fuel in power plants. It is also unlikely that underground carbon storage be considered in the short term, given the risk of CO 2 plume migration that may displace brine in saline formations into strata containing hydrocarbon resources or potable. It is therefore imperative that substantial research be conducted to identify storage sites, reduce energy consumption in carbon capture and develop alternatives to CCS in the form of carbon conversion into useful products or minerals with low environmental impact. The GCC have tremendous opportunities to lead the world in carbon management given their strong experience in hydrocarbon processing. However, this may only be successful if agreed policies and legal frameworks are in place to facilitate a robust carbon pricing. Qscience

Qatar has experienced an unprecedented development in recent years as a result of its large oil and gas industry. It has the third confirmed reserve of natural gas in the world. With 55.4 tonnes of carbon dioxide per person, Qatar has the highest carbon footprint globally, about 10 times the global average. Against this background, there have been attempts to investigate ways to reduce carbon emissions since CO2 was deemed to be one of the major green house gases. Power generation is by far the biggest contributor to anthropogenic (man-made) carbon emissions. The carbon emission mitigation methods currently considered include both “end of pipe” and “at source” solutions. The techniques currently identified to capture carbon emissions from point sources from industrial activities include post combustion capture, precombustion capture and oxyfuel based capture. These techniques are currently at various stages of development. In this work, an important petrochemical process, namely the Vinyl Chloride Monomer (VCM) process has been selected for carbon footprinting. The primary fossil fuel equivalents, which in turn will be turned into CO2 emissions using combustion processes, were identified. Industrial standard simulation software HYSYS was used to carry out the calculations on the heat duties of the entire plant. Energy intensive sections in the VCM process were identified and their associated CO2 footprint calculated. The total CO2 emissions from VCM plant with a hypothetical capacity of 300,000MT/yr were estimated to be around 96,000 MT/yr, which means that for each 1 ton VCM produced, 0.32 ton of CO2 is emitted. In addition to the process related carbon emissions, non process CO2 emissions were estimated. This emission emanates from energy used to power lighting, electronic equipment, catering, in-house transportation etc. Good practice for energy saving and hence CO2 emission reduction was put forward.

The process industry utilizes thermal energy on a massive scale and rejects a significant proportion into the environment as a low grade heat. The definition of low grade heat is fuzzy and is somewhat related to the temperature of the stream carrying such thermal energy. Estimates of low grade heat emissions are hard to compile accurately on a global scale but these are likely to be of the order of thousands of trillions of BTUs. In some cases, up to 50% of thermal energy consumed is eventually rejected as low grade heat. This waste is not only uneconomical but also environmentally damaging since it carries a carbon footprint. Modern process plants reduced a great deal of thermal energy losses through heat integration and energy recovery. However, due to process temperature requirements, a vast amount of thermal energy denoted as low grade heat is still rejected. The objectives of this work include evaluating the possibility of utilizing the low grade heat outside the process generating, in a useful manner that has both economic and environmental benefits. In the Middle East where the oil and gas industry rejects vast amounts of low grade heat, recovery and utilization for desalination is becoming a serious option. This work proposes utilization of low grade heat in membrane distillation for desalination and establishes a balance between capital and operating costs as well as carbon footprint reduction. The work is based on a couple of case studies involving well established processes, namely the vinyl chloride monomer and gas-to-liquids processes. The recovery of low grade heat will be coupled with seawater cooling thus providing a warm source of salty water feed to the membrane distillation system. The work indicated that quality potable water may be produced for the petrochemical plants and neighboring living quarters at a reasonable cost. This approach may reduce the demand for fresh water from desalination plants in major industrial complexes making these self-sufficient in fresh water. Benefits are both economic and environmental.

The concentration of CO2 in the atmosphere keeps increasing, relentlessly approaching the critical threshold identified as a point of no return for global warming. Recent research on carbon sequestration revealed that emission reduction targets would be hard to achieve with a single solution, namely underground storage, since a great deal of issues are still outstanding. To name but a few of these, one can cite a legal framework, international cooperation and availability of underground storage sites of sufficient quality and capacity. The nature of the outstanding issues is truly global, requiring a global approach for carbon management. Work supported by QNRF addressed important aspects of carbon management and constitutes the basis for the work presented herein. The objectives of this work include a balanced analysis of CO2 mitigation methods currently being tested or still under development, and the best way forward to break the cycle of undecisiveness currently being adopetd by most nations. The topics covered include carbon capture, underground storage in both depleted reservoirs and saline aquifers, carbon conversion, energy efficiency and development of carbon sinks on a global scale. The work has shown so far that the bulk of man made carbon emissions arise from combustion processes, essentially power generation using fossil fuels, and this is relatively well documented by the international energy agency compared to other sources of emissions. The cost of capturing combustion CO2 constitutes the bulk of the composite cost of carbon capture, storage and utilization (CCSU). Once CO2 is captured, it has to be disposed of where facilities are available. In the absence of suitable storage sites, other forms of carbon emission reduction have been identified and would include energy efficiency, carbon conversion and mandatory carbon sinks. The work has shown that it is practically impossible to expect all nations emitting CO2 to employ CCS only. The work achieved is of great significance in highlithing the complexity of carbon management on a global scale and offers alternatives that are both technically feasible and economically balanced.

We examine the effect of various contributory factors, such as structural properties, on the pressure drop of fluids through packed beds so that appropriate correlations with wide practical applicability can be established

Publisher Summary Environmental sustainability is becoming a serious challenge due to the global economic growth coupled with a massive surge in energy demand from new economic powers. The nature of the environmental challenge is extremely complicated since it is a composite of scientific misunderstanding, technological advances, public perceptions and political decisions. This unusual combination is not random since it is directly related to the intimate connection between strategic energy policies, public pressure for green house gas emission reduction and an aspiration for a better quality of life. The second annual gas processing symposium program included a discussion forum that brought academics and people from industry round a table to discuss timely and important topics linked directly or indirectly to environmental sustainability of gas processing operations. This chapter is an attempt to put in perspective future trends driven by joint efforts from academics and people from industry for environmental sustainability in the oil and gas industries.

Global trends in VCM and PVC were reported and raw material price impact highlighted. These trends and the lack of availability of economic studies of petrochemical projects in the public domain motivated the need to carry out an economic study for VCM projects. Indeed, apart from China, current VCM producing countries suffer from exceptionally high raw material and labor costs, casting doubt on the economic viability of new VCM capacity there. It was found that with the current basic feedstock prices, new VCM projects would not be economically feasible in the USA or Western Europe, but would be so in the Middle East with overall rates of return around 27% and pay back periods around 6 years. The approach adopted in this study can also serve as a guide to ensure reliability for process optimization studies that traditionally tend to employ outdated or unrealistic economic data.