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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Quarterly Journal of Applied Chemical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Gas Hydrate,Constant volume size,Equilibrium conditions
- چکیده:
- چکیده انگلیسی: One of the main problems in oil recovery via the gas injection is the formation of hydrates in the
lines. In order to prevent the formation of hydrate in these lines, which leads to the blockage and
sometimes explosion, at first, the equilibrium formation conditions must be determined and then to
prevent its formation by changing the thermodynamic conditions or by adding the inhibitors. In this
research, the hydrate formation for a natural gas sample has been studied under the various
thermodynamic conditions. For this purpose, a gas sample was taken from the natural gas
transmission lines. Then, the conditions for the formation of gas hydrates were determined from the
experimental equations. Also, by constructing and launching a laboratory system, the experiments
were carried out using the Isochoric method and the hydrate formation conditions were determined.
The experiments were done at a temperature range of 264 to 300 K and a pressure range of 5 to 45
bar in the pure water. The results showed that, with increasing temperature, the equilibrium pressure
of the hydrate formation increases and with increasing pressure, the equilibrium temperature of
hydrate formation is reduced.
- انتشار مقاله: 14-03-1397
- نویسندگان: Mohsen Kasaeezadeh,Alireza Azimi
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Chemical and Biochemical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Adsorption,Nanofiltration,Membrane,Haloacetonitrile
- چکیده:
- چکیده انگلیسی: In this study removal of haloacetonitriles from aqueous solution by employing a novel hybrid filtration process is investigated. The application potential of the oxidized multi-walled carbon nanotubes (O-MWCNTs) as adsorbent was investigated by evaluating the effect of different process parameters. Solution pH significantly affected the removal of DCAN (as a model of HANs) due to its strong effect on the charges of the adsorbent and the adsorbate. A maximum DOC removal of 98.7% for was achieved with 150 mg/L oxidized MWCNTs dosage and at a solution pH of 8. Finally, the nanofiltration technique using a PBS membrane was effectively employed to reject the wastewater pollutants (HANs) proprly.
- انتشار مقاله: 08-05-1399
- نویسندگان: Mohsen Vaziri,Seyed Mostafa Tabatabaee Ghomsheh,Alireza Azimi,Masoomeh Mirzaei Ghaleh Ghobadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Progress in Chemical and Biochemical Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Crude Oil,hydrogen,Naturl Gas,molar component of water
- چکیده:
- چکیده انگلیسی: Natural gas and crude oil in natural underground reservoirs are in contact with water. Stability of these compounds at the presence of both components and complete dependence on the host molecules by forming holes in their guest molecules are replaced. There are many gases such as methane, ethane, propane, carbon dioxide, hydrogen sulphides that can play the role of guest molecules. The natural gas hydrate formation in different sectors of the oil and gas industry in downstream processes causes the production to stop or decrease. Therefore, the need to know the causes and conditions of hydrate formation is strongly felt. In this study, Van der Waals and Platteeuw model was used to predict hydrate formation conditions. The prediction of hydrate formation conditions needs equilibrium fugacity of gaseous components, and for the equilibrium molar component of water.
- انتشار مقاله: 15-06-1398
- نویسندگان: Alireza Bozorgian,Zahra Arab Aboosadi,Abolfazl Mohammadi,Bizhan Honarvar,Alireza Azimi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Medicinal and Chemical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Zeolite,catalysts,Gasoline Units,Normal-heptane,Light Naphtha
- چکیده:
- چکیده انگلیسی: The aim of this study is to investigate naphtha Gasoline unit catalysts. In two-factor catalysts, platinum or palladium was used as the active metal on the base alumina chloride, zirconia, and zeolite. Considering the fact that refining and gasoline processes are expanding and refineries in Iran are required to produce cleaner fuels that meet environmental standards, investigating different kinds of light naphtha gasoline unit catalysts can greatly help to promote production of clean fuel and make production process more efficient. Light naphtha gasoline is normally conversion of normal pentane and normal hexane compounds to its branched compounds. Also Light naphtha its derivatives and it is done by chlorinated ammonia or zeolite catalysts in one or some fixed bed reactors. Activity of two-factor catalysts strongly depends on acidic and metal sites. For example, in catalyst Pt./HY, which is a kind of zeolite catalyst for Gasoline Units, the optimal ratio of strong acidic sites to metal sites in n-heptane Gasoline is determined to be less than 6. In this work, various kinds of catalysts used in isomerization unit were identified and considered.
- انتشار مقاله: 13-01-1398
- نویسندگان: Amir Samimi,Soroush Zarinabadi,Amir Hossein Shahbazi Kootenaei,Alireza Azimi,Masoumeh Mirzaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Chemical Reviews
- نوع مقاله: Journal Article
- کلمات کلیدی: aromatic compounds,reactor,Catalyst Poisoning,Naphtha Feed
- چکیده:
- چکیده انگلیسی: The catalytic conversion of naphtha is a refinery process in which heavy naphtha feeds through the catalytic bed of several reactors at high temperatures and pressures that potentially increase the aromatics content of naphtha and its octane number. Usually, naphtha feed is used to remove the impurities that prevent useful reactions and cause poisoning of reformer catalysts. Operating abutments for the catalytic converter unit are temperature, pressure, metallurgical agent, hydrogen to hydrocarbon ratio, and chlorine ratio. In this study, Operational Conditions in Octanizer and Hydro-treating Units in oil refinery companies is investigated and optimized the conditions of catalysis.
- انتشار مقاله: 08-03-1398
- نویسندگان: Amir Samimi,Soroush Zarinabadi,Amir Hossein Shahbazi Kootenaei,Alireza Azimi,Masoumeh Mirzaei
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of New Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی: Nano-silica,Rheology,Fluid Migration,Well Cementing,preventing strategies
- چکیده:
- چکیده انگلیسی: There are various vital reasons for cementing operation, in which fluid migration through cement slurry, as one of the most dangerous and complicated challenges faces drilling industry has been occurred. This phenomenon has become a global problem with its disastrous effects this review paper focused on the gas migration types, factors affecting on each of them and some theoretical and experimental solution. Immediate, short term and long term are the three types of gas migration based on the lifecycle of the well. There are different strategies to prevent gas migration, each type of migration have special strategies. Technical solution development, application of different cement additives in cement slurry and prediction technique for cement quality are number of strategies are developed. Hydrostatic pressure less than pore pressure and the existence of a path to gas migration are two major factors that must be stopped simultaneously to prevent migration. Understanding the mechanisms of cement hydration in early times is necessary to investigate these factors. Cement hydration can lead to swelling and shrinkage at the same time. At the beginning of cementation chemical shrinkage occurs, followed by swelling and autogenously shrinkage, and their intensity depends on the type and amount of the cement additives, the degree of hydration, the water-cement ratio and the fineness of cement. The most important factors that make the annulus pressure less than the pore pressure are: cement placement, Cement hydration in liquid state, and Cement hydration in solid-liquid state.
- انتشار مقاله: 17-11-1398
- نویسندگان: Mahmoud Bayanak,Soroush Zarinabadi,Khalil Shahbazi,Alireza Azimi
- مشاهده
- جایگاه : پژوهشی
- مجله: Chemical Methodologies
- نوع مقاله: Journal Article
- کلمات کلیدی: Adsorption,Haloacetonitrile,Nano-filtration,Hybrid adsorption
- چکیده:
- چکیده انگلیسی: The haloacetonitriles (HANs) exist in drinking water exclusively as byproducts of disinfection. HANs are found in drinking water more often with higher concentrations. Human exposure occurs through consumption of finished drinking water, oral and dermal contact as well as when showering, swimming and other activities. The purpose of this study was to investigate the novel hybrid adsorption/ PBS membrane filtration process used to remove haloacetonitriles from aqueous solution. The efficiency of the PAC adsorbent was also evaluated at different pH, which confirmed efficacy of PAC at pH of 8.A maximum removal of DOC (98.7%) was obtained with 150 mg/L PAC dosage at a solution pH of 8. HANs sorption process followed the pseudo second order kinetic model and the Langmuir isotherm gave the best correlation of adsorption.
- انتشار مقاله: 18-03-1399
- نویسندگان: Mohsen Vaziri,Seyed Mostafa Tabatabaee Ghomsheh,Alireza Azimi,Masoomeh Mirzaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Chemical Methodologies
- نوع مقاله: Journal Article
- کلمات کلیدی: corrosion,Coating,electrochemical reaction,Initial adhesiveness,oil and gas
- چکیده:
- چکیده انگلیسی: Corrosion has been the greatest problem in oil and gas industry, and many experts have always tried to combat this major problem. This has been given to the corrosion and inspection in oil and gas industry. Corrosion in oil and gas wells is driven by some electrochemical mechanisms, and when the system reaches a temperature below the dew point, the moisture will be converted to liquid and many droplets form on the pipe's wall. The corrosion in pipelines' coatings is one of the main problems in oil and gas industries for which a huge amount of money is spent each year. Coating is the first defense line in front of a corrosive environment in which pipes have been buried. Good function of coating depends on its adhesion to the metal surface. Finally, according to our results in this article, we show that, the chemical compounds inside the coating such as chlorides and sulphides can play an electrolyte role, which accelerates corrosion.
- انتشار مقاله: 20-03-1398
- نویسندگان: Amir Samimi,Soroush Zarinabadi,Amir Hossein Shahbazi Kootenai,Alireza Azimi,Masoumeh Mirzaei
- مشاهده
- جایگاه : پژوهشی
- مجله: Advances in Environmental Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Carbon Dioxide,absorption kinetics,nanoparticle,anionic surfactant,amine solvent
- چکیده:
- چکیده انگلیسی: Amine solvents are extensively used on an industrial scale for removing carbon dioxide (CO2). The presence of some additives in amine solvents has a desirable effect on CO2 absorption kinetics and also improves the absorption process. In this study, graphene oxide (GO) nanoparticles and the anionic surfactant sodium dodecyl sulphate (SDS) were used as additives to the amine solvent. The number of CO2 moles that were used (ng), the values of the diffusion coefficient (DAB), and the mass transfer coefficients of CO2 gas absorption in the amine solvent (Kc) were determined. Furthermore, the effect of the additives on the kinetics of CO2 gas absorption in the amine solvent was investigated. The results showed that mass transfer coefficients increased with a decrease in pressure and an increase in temperature as well as in the SDS and GO concentrations. The values of the mass transfer coefficient under different conditions varied between 0.0311 and 0.0587 cm/s. The molecular diffusion coefficient of CO2 in the amine solvent increased from 0.000025 to 0.000287 cm2/s with decreases in the pressure and with increases in the temperature and increases in concentrations of additives. The laboratory data were statistically analyzed via Design-Expert software using response surface experiment design and a historical method. A mathematical relation was proposed to estimate the mass transfer coefficients. Moreover, a mathematical relation was introduced to predict the molecular diffusion coefficient of CO2 in the amine solvent.
- انتشار مقاله: 25-07-1397
- نویسندگان: Abdollah Mohammadpoor,Masoomeh Mirzaei,Alireza Azimi,Mostafa Tabatabaee Ghomshe
- مشاهده