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No 7
Vol. 7 No. 5
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In this article, 23 methods for emission reduction in gas transmission facilities, including compression stations, transmission pipelines and valve stations, have been assessed according to operability, technical feasibility and economic profit. Emission reduction potential, payback period, capital and operating costs have been considered as the main criteria, based on which, all methods have been categorized in three levels. Weight factors were considered for each criterion to quantify the ultimate analysis and prioritize based on total score. Net present value (NPV), internal rate of return (IRR) and added value were also considered to precise economic calculations. The results showed that direct inspection and maintenance (DI&M) for valve stations possessed the highest priority, followed up with DI&M for launcher-receivers and pipeline. Utilization on absorbed natural gas (ANG) for turbine starter exhaust gas had the least interest among other methods.
- Kazem Kashefi
Keywords : Emission Reduction, ، Greenhouse Gases, ، CDM, ، Gas Transmission
Compete and consistent source identification, followed up with accurate emission measurement is the first but the most important step in reduction and controlling of greenhouse gases. Methane and carbon dioxide emission from Iranian gas transmission facilities is discussed in this article. All compression stations and transmission pipeline across the country are within the boundary of this research. Different emission types (fugitive, vent and combustion) in various operating modes (normal, maintenance, startup and process upsets) were considered and annual emission rates for all identified sources were measured or estimated, based on emission/activity factors methods. Stations age and capacity, types of turbines and compressors and the ratio of capacity to number of runs, were considered in statistical analysis. The results revealed 25 emission categories, among which, fugitive emission from station valves was the greatest with 37.8% share of total emission. Fugitive emission from blow-downs of launcher-receivers (20.7%), fugitive from above-ground pipelines (12.2%), combustion emission in stations (12.5%) and vent from compressor seals (10.8%) were in second to fifth order among all other emission sources.
- Kazem Kashefi
Keywords : Greenhouse Gases, ، Emission, ، Gas Transmission, ، Compressor Station
Consumption of conventional gas reservoirs and development of drilling, logging and coring technology, many countries and scientists have focused on the gas hydrate explorations. Recently many successful gas hydrate wells have been drilled in the world which is often on the marine environment. Almost one decade ago, it was considered that drilling in gas hydrate reservoirs was quite risky. However, recent drilling expeditions in marine environment show that gas hydrate does not risky and big oil services companies encourages to development of these drillings. Because successful drilling results withdrawals from gas hydrate reservoirs does not dissociate immediately and consequently lot of considered theoretical problems ruled out of the drilling of these reservoirs. It is obvious that special cares should be taken to maintain gas hydrate reservoirs as stable as possible with drilling fluid selection and cement composition selection. This paper presents a comprehensive perspective on the results of drilling activities in the gas hydrate reservoirs.
Ahmad Ghozatloo
Keywords : Gas Hydrate ، Drilling ، Logging ، Coring ، ،
Buildings are one of the major energy consumers in Iran. Electricity in this section is supplied by thermal power plants with low efficiency and high pollution emissions. Today, the development and deployment of novel power generation systems with high efficiency and independent of the network with low emissions are important and extensive researches have been devoted to them. Fuel cell is one of these systems. In this paper, the application of Solid Oxide Fuel Cell (SOFC) as a prime mover of a cogeneration system to supply energy demands of a typical residential building has been analyzed from technical and economic points of view. The process of SOFC was simulated using Aspen Plus software and the possibility of heat recovery from SOFC high temperature exhaust gas to activate a double effect absorption refrigeration cycle by steam generation and hot water production in a heat recovery heat exchanger was examined. The power and efficiency of heating and power cogeneration and heating, power and cooling cogeneration systems versus inlet fuel rates was obtained. Based on building energy consumption model, the produced powers and building loads matching conditions were obtained based on minimum annual energy cost. Economic analysis has shown that annual energy consumption cost in cogeneration system compared with a separately produced power system will be drastically reduced. With the commercialization of SOFC technology and further reduce manufacturing costs, this system can be very suitable alternative to conventional power generation systems.
- Ali Rahimi Khameneh
Keywords : Cogeneration, ، SOFC, ، Heat recovery, ، Aspen Plus, ، Building
In this paper I will try to compare the presently practised design on warming up of sulfur reactor beds to 300 degree farnhyte in SRU start ups from cold against the concept of cold reactor bed start ups designed & developed by the Ortloff of USA from 1970 and is practiced in their designed plants since then . To me , the cold reactor bed start up is a much better theory and has many advantages. To effect this theory , Ortloff utilises 2 especial controll valves for bypassing the beds during the plant warm up from cold (to keep them safe from harm ) . I have come to realise that the use of those control valves which are so sophisticated and expensive and can be troublesome are not required and installation of 2 hammer blinds can effectively displace those valves and create a more reliable operation.
Keywords : Sulfur recovery unit ، Clause process(reaction) ، Cold theory of reactor bed start up ، Reactor bed warm up ، Hammer blind ،

ابتداقبلی12بعدیانتها مشاهده 1 تا 5 ( از 10 رکورد)