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[en] Present article is devoted to concept substantiation of selected technologies on deep coal processing. The basic aspects of coal gasification were studied. The selection state of optimal technology of coal gasification was considered. The optimal technologies of gas processing were proposed.
[en] Bechtel, along with Amoco as the main subcontractor, developed a Baseline design, two alternative designs, and computer process simulation models for indirect coal liquefaction based on advanced Fischer-Tropsch (F-T) technology for the U. S. Department of Energy's (DOE's) Federal Energy Technology Center (FETC)
[en] This patent deals with a Fischer-Tropsch catalyst comprising iron co-deposited with or deposited on particles comprising a mixture of zirconia and titania, preferably formed by co-precipitation of compounds convertible to zirconia and titania, such as zirconium and titanium alkoxide. The invention also comprises the method of making this catalyst and an improved Fischer-Tropsch reaction process in which the catalyst is utilized
[en] The effect of Mn-promotion on high surface area Al-pillared montmorillonite (AlMMT) supported Co nanoparticles prepared by hydrothermal method have been investigated. A series of different weight% Mn-promoted Co nanoparticles were prepared and characterized by XRD, TPR, TGA, BET and SEM techniques. An increase in the surface area of MMT is observed with Al-pillaring. Fischer-Tropsch catalytic activity of the as prepared catalysts was studied in a fixed bed micro reactor at 225 .deg. C, H2/CO = 2 and at 1 atm pressure. The data showed that by the addition of Mn the selectivity of C1 dropped drastically while that of C2-C12 hydrocarbons increased significantly over all the Mn-promoted Co/AlMMT catalysts. The C13-C20 hydrocarbons remained almost same for all the catalysts while the selectivity of C21+ long chain hydrocarbons decreased considerably with the addition of Mn. The catalyst with 3.5%Mn showed lowest C21+ and highest C2-C12 hydrocarbons selectivity due to cracking of long chain hydrocarbons over acidic sites of MMT
[en] The process concerning the chemical transformation of natural gas into oil-based products (a so-called 'clean' diesel) known under the term GTL FT (Gas To Liquids - Fischer Tropsch) will turn a new page in its history with the start-up of a major unit in Qatar in 2006 Up until now only two GTL units were deployed, in the early 1990's (Moss as and Shell) without however resulting in the widespread expansion of this process. The technological breakthroughs achieved around the year 2000 combined with a favourable background context (concerning geopolitical tension, ears of oil production peaks, significant increases in the price of crude) now account for much of the interest shown in this solution. Consequently, outside Qatar, projects are also being looked at in various natural gas producing countries such as Nigeria or Algeria. It would be justified however to think that a new wave of natural gas recycling will gradually emerge as part of the global energy market. (author)
[en] The effect of solvent on the hydrogen-deuterium isotopic homomolecular exchange over a traditional Fischer-Tropsch cobalt catalyst (25 % Co/Al2O3) was investigated using a plug flow reactor at two different reaction temperatures (room temperature (26 oC) and -20 oC) and at atmospheric pressure. In this study, three different solvents were tested, including n-pentane, n-hexadecane, and C-30 oil. The consumption of H2 and D2 is the same, and the concentration of the HD produced is twice the consumption of H2 or D2 at dry (without solvent) conditions. At room temperature and at -20 oC, conditions without solvent exhibited 100 mol% exchange with the formation of H2:HD:D2 having a 1:2:1 ratio. For n-pentane solvent, the exchange rates were ∼97 and ∼80 mol% at 26 and -20 oC, respectively. For the n-hexadecane and C30 oil solvents, the initial exchange rate was ∼50 mol%, with the exchange rate decreasing over time. The lower exchange rate with the n-hexadecane and C30 oil solvents, and also n-pentane at -20 oC, is likely due primarily to the limited mobility of reactant molecules in the liquid-filled pores of the catalyst. Blocking or covering of the pores of the catalyst depends on the molecular mass and density of the solvent. No isotopic partitioning preference was observed at two different temperatures and various solvents for the active cobalt catalyst. (author)
[en] Significant savings are being realized from the consolidated tritium gas-processing operations at the Savannah River Site. However, the trade-off is some reduction of operational flexibility due to decreased storage capacity for process and waste gases. Savannah River National Laboratory researchers are developing an integrated process gas model for tritium processing using Aspen Custom ModelerTM (ACM) software. The modeling involves fully characterizing process flow streams (gas composition, quantity), frequency of batch transfers, and availability of equipment in the flow stream. The model provides a valuable engineering tool to identify flow bottlenecks, thereby enabling adjustments to be made to improve process operations. (authors)
[en] The demand for cleaner automotive fuels has created an opening for converting natural gas to liquid transport fuels and blending agents using Fischer-Tropsch technology. While the technology is well established, it is not yet clear whether the conversion can compete with crude oil refining or with pipelines and liquefied natural gas. Although all the oil giants are interested in the technology, the only commercial-sized plant in the world was the Shell plant in Malaya which had capacity of 12,000 bpd, but the profitability of the plant came from the wax by-products. The plant has been closed since a fire and explosion in 1997. The process chain is described. The gas-to-liquid activities and achievements of Saol, Exxon and Texaco are reported. It was concluded that although there are still some problems to be ironed-out, there is a promising future for gas-to-liquid conversion. (UK)
[en] Highlights: • Biofuels are produced by Fischer-Tropsch synthesis using the syngas obtained by supercritical reforming. • A plant capacity of 60 t/h and a feeding concentration of 25 wt% were established as the base-case. • The aim of the energy self-sufficient process was to maximize the biofuel production and electrical power. • The break-even prices were 1.20, 0.93 and 0.26 €/kg for gasoline, diesel and jet-fuel, respectively. • The process competitiveness is promising with respect to that of fossil fuels of crude oil. - Abstract: High energy demand along with large capital costs have been the main drawbacks of Fischer-Tropsch plants, which may call into question the economic viability of the Fischer-Tropsch process. The second issue is the focus of this paper, which presents a techno-economic assessment of biofuels production by a low-temperature Fischer-Tropsch synthesis with electricity as a co-product from supercritical water reforming of the bio-oil aqueous phase. A plant size of 60 t/h was considered and a heat-integrated process was designed to be energy self-sufficient, which includes syngas production and upgrading, as well as liquid fuels production by Fischer-Tropsch synthesis and refining. The simulation and optimization was performed with the aid of Aspen Plus, and some case-studies were performed. Using a feeding concentration of 25 wt%, 2.74 t/h biofuels and 5.72 MWe were obtained. In this case, by performing a discounted cash flow analysis, with 10% rate of return and 100% equity financing, the minimum selling prices for the refined FT-gasoline, FT-diesel and FT-jet fuel were 1.20, 0.93 and 0.26 €/kg (0.84, 0.75 and 0.20 €/L), respectively, which are competitive prices with respect to the market values of the equivalent fossil fuels. Likewise, the decrease in the selling prices as the plant capacity increases was also analyzed.