Search

Search for Article,Author or ...

News

Current Issue

No 8
Vol. 8 No. 5
2019
Download |

Last Published Articles

The presence of S8 in natural gas streams has caused many problems at the delivery points and measuring equipment. There are many treatment processes, including absorption, adsorption, membranes and conversion processes. In this work, a literature review was carried out on the main methods available for removal of sulfur compounds from gas streams as well as an analysis of the feasibility of its application in pipelines. The results showed that, due to the complexity of the processes and to the costs involved in implementation and maintenance, the mechanisms of control by adsorption are the most attractive for use in pipelines.
- Javad Salimi
Keywords : Natural gas, ، Desulfurization processes, ، Elemental sulfur, ، Adsorption
Abstract In this research, the process of formation of methane hydrates was investigated in the presence of graphene and graphene oxide. First, the graphene nano sheets synthesized and growth on the copper substrate by the CVD method and It was structure was evaluated by XRD, FTIR and AFM analysis. Then, 1% wt. of stable graphene and graphene oxidized nanofluids were prepared and used in the process of gas hydrates formation at 1000 psig and at 4 C. As the nanofluid containing graphene / surfactant, while reducing the Induction and dissolution time to 46.0% and 60.9% respectively, compared to the pure water, could increase the storage rate to 56.7%. This is due to an increase of 40 times the initial dissolution of methane in the nanofluid than water, which is due to the reduction of the mass transfer resistance due to the presence of surfactant and the presence of heterogeneous active sites for nucleation. It was observed, however, the stability of hydrates in presence of graphene is less than graphene oxide, but after reaching the stability, the amount of methane deposited in graphene hydrate is greater than control sample of 34.9.
Ahmad Ghozatloo
Keywords : Methane Hydrates, ، Graphene, ، Surface Properties, ، Oxidation, ، Induction, ، Stability, ، Storage
Nowadays, natural gas refineries have been developed to purify natural gas and optimize the extractive gas properties of gas wells for various uses, such as home use. Each gas refinery is composed of a set of process units, each of which can be a factor in the emission of greenhouse gases into the environment. Therefore, the purpose of this paper is to first study and estimates the greenhouse gas emissions of the process units in the two refineries of Shahid Hasheminejad and Fajr Jam and then provides solutions to improve performance and reduce carbon dioxide emissions in these refineries. Generally, greenhouse gas emission sources are divided into three sections: combustion, process and fugitive emissions. In the combustion section, four mass balance methods (based on the amount and composition of fuel), stack outlet gas analysis method, stack outlet gas analysis method and general propagation coefficient method have been used for both refineries. Comparison of the results of these four methods for boilers in these two refineries shows that the mass balance method will result in more accurate results in calculating the CO2 emission and emission factor for the calculation of the CH4 emission. Also, the fugitive emission related to equipment leakage of wastewater treatment process related to these two refineries has been estimated. The results of the estimation of greenhouse gas emissions in these two refineries show that the flaring of gases, carbon dioxide in the raw gas entering the refinery and fuel consumption in the energy conversion equipment are three main sources of greenhouse gas emissions. Therefore, 11 projects to improve the efficiency and reduce carbon dioxide emissions in these two refineries have been presented around the flaring reduction, improving energy efficiency (in all three sectors of production, transmission and consumption), and CO2 capture from exhaust gases from the stack of furnace.
- Kazem Kashefi
Keywords : gas refinery ، greenhouse gas emissions ، emission reduction ، performance improvement ، sustainable development
One of the main problems in gas condensate wells occurring by increasing gas production and reducing pressure in gas condensate reservoirs is gas condensates loading and water in well, followed by reduced gas production and finally cut off gas production and condensates and extracted with gas from well. Thus, it is important to recognize the signs of liquid loading in the gas-producing wells in the initial stages and to provide a suitable solution for gas wells, and thus, to minimize the negative effects of fluid fall into the well opening. This paper examines the effect of various parameters on the liquid loading phenomenon in one of the well fields of Pazanan gas condensate. It was conducted to examine different factors and find the best solution for optimization in the studied wells. Finally, by providing the most suitable solution for the studied well, the rate of liquid loading in the studied wells is reduced and the economic profit resulting from optimization, high economic savings of this method and its efficiency are confirmed. Comparison of the results obtained from this study and simulation with Pipesim software shows that the results have a good accuracy for the new well completion and these results prevent liquid loading and optimizing and increasing production in the field studied at the current time and, ultimately, very high economic profit of optimizing and return on capital in the field studied.
Masoud Bijani - - Siamak Mohamadi Azad
Keywords : gas condensate well ، liquid loading ، tubing ، optimization ، economic profit ، production well
In this configuration, the thermal couplings of two processes in terms of catalytic bed have been studied. The catalytic bed contains a fix bed and a fluid bed. The processes under study in this project are the methane tri-reforming process in the calefactory section and the methanol dehydrogenation process in the endothermic section, which are carried out separately in the plug reactor. In this modeling, once a methane tri-reforming process in a fixed bed and once in a fluid bed with a methanol dehydrogenation process in a fixed bed in improved coupling method are coupled, and their results have been studied and compared. The results of this modeling indicate the feasibility of coupling of the two processes. In this project, a homogeneous, one-dimensional and stable model is proposed to predict the behavior of these reactors. The rates of methane conversion in the fixed bed and in the fluid bed in the calefactory section were obtained as 92.9% and 90%, respectively; and the yields of hydrogen in the fixed bed and fluid bed were obtained as 1.8 and 1.75, respectively; and the H₂/CO ratio in the fixed bed and fluid bed ware obtained as 1.94 and 2.02, respectively. Generally, according to the results, the yield of the fixed bed coupling for this configuration is more favorable in methane conversion and yields of hydrogen than that of the fluid bed coupling.
Marjan zare - Zahra Arab
Keywords : Methane Tri-Reforming, Methanol Dehydrogenation, Fixed Bed, Fluid Bed, Thermal Coupling Reactor

ابتداقبلی12بعدیانتها مشاهده 1 تا 5 ( از 10 رکورد)