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1.
Artigo em Inglês | MEDLINE | ID: mdl-35682073

RESUMO

The rapid growth and urbanization rate, coupled with hot climate and scarce rainfall, makes it essential for a country like Kuwait to have several power and desalination plants with high-generating capacity. These plants are entirely reliant on burning fossil fuels as a source of thermal energy. These plants are also universally accepted to be the largest CO2 emitters; hence, they present a potential for carbon capture and storage (CCS). Having established the suitability of the existing conditions for post-combustion CCS, a techno-economic-based feasibility study, which took into consideration local power generation technologies and economic conditions, was performed. Relying on fifteen case study models and utilizing the concept of levelized cost of electricity (LCOE), the statistical average method (SAM) was used to assess CCS based on realistic and reliable economic indicators. Zour power station, offering the highest potential CO2 stream, was selected as a good candidate for the analysis at hand. Heavy fuel oil (HFO) was assumed to be the only fuel type used at this station with affixed price of USD 20/barrel. The analysis shows that the internal rate of return (IRR) was about 7%, which could be attributed to fuel prices in Kuwait and governmental support, i.e., waived construction tax and subsidized workforce salaries. Furthermore, the net present value (NPV) was also estimated as USD 47,928 million with a 13-year payback period (PBP). Moreover, 1-3% reductions in the annual operational cost were reflected in increasing the IRR and the NPV to 9-11% and USD 104,085-193,945 million, respectively, and decreasing the PBP to 12-11 years. On the contrary, increasing the annual operational cost by 1% made the project economically unfeasible, while an increase of 3% resulted in negative IRR (-1%), NVP (-USD 185,458 million) and increased PBP to 30 years. Similarly, increasing the HFO barrel price by USD 5 resulted in negative IRR (-10%) and NVP (-USD 590,409); hence, a CCS project was deemed economically unfeasible. While the study considered the conditions in Kuwait, it is expected that similar results could be obtained for other countries with an oil-driven economy. Considering that around 62% of the fossil fuel blend in Kuwait is consumed by electricity and water generation, it is inevitable to consider the possibility and practicality of having a carbon network with neighboring countries where other oil-driven economies, such as Kingdom of Saudi Arabia and Iraq, can utilize a CCS-based mega infrastructure in Kuwait. The choice of Kuwait is also logical due to being a mid-point between both countries and can initiate a trading scheme in oil derivatives with both countries.


Assuntos
Carbono , Centrais Elétricas , Dióxido de Carbono , Estudos de Viabilidade , Combustíveis Fósseis , Kuweit
2.
J Air Waste Manag Assoc ; 69(10): 1142-1169, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31184550

RESUMO

This study reports on the occupational inhalation exposure to VOCs of workers in the Kuwaiti printing industry. Using the evacuated canister methodology, we targeted 72 VOCs in three printeries and compared the concentrations to previous reports and relevant occupational exposure levels (OELs). We found that recent efforts in the printing industry to reduce VOC usage had been successful, as concentrations of key hazardous VOCs were substantially lower than anticipated. On the other hand, nearly all target VOCs were found. Non-production areas were sampled along with the offset printing areas, another strength of this study, and revealed exposures to hazardous VOCs among administers and digital printer and CTP operators. Exposure to ototoxic VOCs amounted to 1-3% of the OEL, consisting mostly of ethylbenzene, which was likely in use in two of the study printeries. Exposure to carcinogenic or probably carcinogenic VOCs was 15-20% of the OEL at four locations across the three printeries, consisting mostly of vinyl chloride and benzyl chloride. Vinyl chloride VOC was partially sourced from outdoors, but was also likely used inside the study printeries. Interestingly, concentrations of vinyl chloride were similar in most sampling locations to that of CFC-114, a CFC banned by the Montreal Protocol and not commonly used as a refrigerant. This unexpected finding suggests further study is warranted to identify the use of these VOCs in printeries. Exposure to hazardous VOCs up to nearly 50% of the OEL, consisting largely of bromoform and vinyl chloride. Bromoform was found in all the study printeries, sourced partially from outdoor air. The higher concentrations found inside the study printeries likely resulted from the use of the desalinated water for washing. This finding raises of emissions from sources other than blanket washes, and inks, etc. adding to the total VOC load in printery indoor air. Implications: Results from this study indicate that efforts to reduce worker exposure to VOCs particularly dangerous to human health in recent years have been successful, but there is still much to be done to protect workers. Exposures to ototoxic and carcinogenic VOCs were identified, among both production and non-production workers. Unexpected findings included the apparent use in printing activities of the carcinogen vinyl chloride and CFC-114, banned under the Montreal Protocol. Observed lapses in safety procedures included failure to utilize ventilation systems and closing doors between work areas, indicating management and worker education should remain a priority.


Assuntos
Poluentes Ocupacionais do Ar/análise , Exposição por Inalação/análise , Exposição Ocupacional/análise , Impressão , Compostos Orgânicos Voláteis/análise , Derivados de Benzeno/análise , Compostos de Benzil/análise , Monitoramento Ambiental/métodos , Humanos , Indústrias , Trialometanos/análise , Cloreto de Vinil/análise
3.
J Air Waste Manag Assoc ; 67(11): 1170-1179, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-27700694

RESUMO

Twenty-four-hour integrated ambient air samples were collected in canisters at 10 locations within Kuwait's major power station: Doha West Power Station to assess the spatial distribution of volatile organic compounds (VOCs) within the perimeter of the station. A total of 30 samples, i.e., three samples per location, were collected during February and March. The samples were analyzed using a gas chromatography with flame ionization detection (GC-FID) system and following the U.S. EPA Method TO-14A with modification. The results reflected the emission activities on the site and the meteorological conditions during sampling. Generally speaking, there was a negative correlation between the ambient temperature and the VOC concentrations, which indicates the sources were local. The halogenated compounds formed the highest proportion (i.e. 50-75 %) of the total VOC concentrations at the ten locations. 1,2,4-Trichlorobenzene and Vinyl Chloride concentrations were the highest amongst the other halogenated compounds. The aromatic compounds formed the least proportion (i.e. 1-4%) of the total VOC levels at all locations with Toluene having the highest concentrations amongst the aromatic compounds at seven locations. Propene, which is a major constituent of the fuel used, was the highest amongst the aliphatic compounds. The findings of this study and other relevant work suggests the measured VOC levels were the highest over the year, nevertheless, further work is required to assess the precisely temporal variation of VOC due to change in meteorological conditions and the emission rates. IMPLICATIONS: Assessment of VOC concentrations around a power plant in Kuwait during the peak season showed halogenated compounds to be the dominant group. The calculated indoor concentrations were lower than those reported in a residential area about 12 km away.


Assuntos
Poluentes Atmosféricos/análise , Centrais Elétricas , Compostos Orgânicos Voláteis/análise , Poluentes Atmosféricos/química , Clorobenzenos/análise , Clorobenzenos/química , Monitoramento Ambiental/métodos , Kuweit , Tolueno/análise , Tolueno/química , Cloreto de Vinil/análise , Cloreto de Vinil/química , Compostos Orgânicos Voláteis/química
4.
Chemosphere ; 168: 147-154, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27776233

RESUMO

A sampling campaign was carried out to assess the impact of the oil field activities on the concentrations of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in ambient air at Umm Al-Aish oil field in northern Kuwait. Sixteen samples were collected from March 2014 to January 2015. The concentrations of ΣPCDD/Fs were relatively high (33.6-586 fg I-TEQ/m3; median: 94.7 fg I-TEQ/m3; 31.2 to 516 fg WHO-TEQ2005/m3; median: 83.7 fg WHO-TEQ2005/m3) compared to those of dl-PCBs (3.9-36.8 WHO-TEQ2005/m3; median 9.9 WHO-TEQ2005/m3). A unique PCDD/F profile that was not previously reported was found. Further investigations should be conducted to establish whether the dioxin profile found in this study is specific for the desulfurization facility located in the study area or from oil flaring in the oil fields located upstream of the study area. The findings suggest that the oil field activities have a significant impact on the PCDD/F concentration in ambient air but a low or negligible influence on dl-PCBs' levels.


Assuntos
Poluentes Atmosféricos/análise , Dibenzofuranos Policlorados/análise , Campos de Petróleo e Gás , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Kuweit
5.
Gynecol Endocrinol ; 22(12): 680-4, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17162710

RESUMO

BACKGROUND: Women with polycystic ovary syndrome (PCOS) are considered to be at increased risk of miscarriage. Since metformin has beneficial effects on the risk factors contributing to first-trimester abortion in PCOS patients, we hypothesized that metformin - owing to its metabolic, endocrine, vascular and anti-inflammatory effects - may reduce the incidence of first-trimester abortion in PCOS women. MATERIALS AND METHODS: A prospective cohort study was set up to determine the beneficial effects of metformin on PCOS patients during pregnancy. Two hundred non-diabetic PCOS patients were evaluated while undergoing assisted reproduction. One hundred and twenty patients became pregnant while taking metformin, and continued taking metformin at a dose of 1000-2000 mg daily throughout pregnancy. Eighty women who discontinued metformin use at the time of conception or during pregnancy comprised the control group. RESULTS: Both groups were similar with respect to all background characteristics (age, body mass index, waist/hip ratio, follicle-stimulating hormone, luteinizing hormone, estradiol and dehydroepiandrosterone sulfate levels). Rates of early pregnancy loss in the metformin group were 11.6% compared with 36.3% in the control group (p < 0.0001; odds ratio = 0.23, 95% confidence interval 0.11-0.42). CONCLUSIONS: Administration of metformin throughout pregnancy to women with PCOS was associated with a marked and significant reduction in the rate of early pregnancy loss.


Assuntos
Aborto Espontâneo/prevenção & controle , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Aborto Espontâneo/etiologia , Adulto , Feminino , Humanos , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Síndrome do Ovário Policístico/complicações , Gravidez , Primeiro Trimestre da Gravidez
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