01989 Synthesis of high polymers using C1 compounds

01989 Synthesis of high polymers using C1 compounds

03 Gaseous fuels (derived gaseous fuels) over A1203 support. The CH4 and Oz conversions increase with pressure and decrease with GHSV. The decrease ...

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03

Gaseous fuels (derived gaseous fuels)

over A1203 support. The CH4 and Oz conversions increase with pressure and decrease with GHSV. The decrease in the conversions with GHSV reveals that the effect of pressure can be eliminated to some extent by increasing GHSV. The conversion of CH4 and the selectivities to CO and Hz decrease with pressure when the catalyst 2.9% Ni/CaA1204-AlzOs is used in the reaction and increasing GHSV weakens this pressure effect.

fuels by partial oxidation and high-temperature and tar obtained from the low-temperature converting the ashes to melting slags.

Pyrolysis of coal with hydrogen atoms 99/m 980 Bi, J. et al. Prepr. Symp. Am. Chem. Sot., Div. Fuel Chem., 1998, 43, (3) 703-706. In understanding the mechanisms of coal liquefaction and coal hydrogasification, the reactions of coal directly with hydrogen atoms are very important. Taiheiyo coal was reacted in a low pressure thermo-gravimeter with hydrogen atoms (induced by microwave discharge cavity) and hydrogen gas under a pressure range of 1.0-50.0 torr and a temperature range of 2&1OOO”C, with heating rates of 5-20”C/min. TG-MS and GC-MS were used to measure and analyse the char, gas and liquid yields. The conversion of coal with hydrogen atoms was higher than that under low pressure of hydrogen gas and more liquid and gas products were obtained in the reaction with hydrogen atoms. In the presence of hydrogen atoms, it was observed that more CO was produced at a relative low temperature. Fewer alkylated naphthalene compounds were produced in the liquid yield in the reaction with hydrogen atoms than in the hydrogen gas atmosphere.

Hanson, S. et al. IChemE Res. Event, Two-Day Symp., 1998, 613-621. A laboratory-scale spouted bed, which can simulate the pyrolysis of coal particles and the gasification of semicoke in an air-blown gasification cycle (ABGC) gasifier was constructed. Prior to its design, trials were conducted at ambient temperature and pressure. Maximum spoutable bed height and minimum spouting velocity were investigated in relation to different reactor sizes and reactor inlet diameters. The influence of the particle size of the bed material was also studied. The Mathur-Gishler equation could be adapted to calculate the minimum spouting velocity, but because it used the bed height in the calculation, it could not be used unless reliable data on maximum bed height was available. The main design parameters were determined empirically because of the number of variables and reasonable doubt about their independence.

Reaction of fuel NO, formation for gas turbine

Chang, M. et al. US 5,821,270 (Cl. 518-700, CO7C27/00), 13 Ott 1998, Appl. 850,356, 2 May 1997, 9 pp. In this process, a reversibly deactivated hydrocarbon synthesis (e.g. Fischer-Tropsch) catalyst in a hydrocarbon synthesis slurry is rejuvenated by passing the slurry through at least two rejuvenation stages external to the slurry reactor, each of which comprises a rejuvenation zone followed by an offgas removal zone. This is accomplished by using a lift pipe outside the reactor into which slurry from the reactor is passed and contacts a catalyst rejuvenating gas to partially rejuvenate the catalyst particles and form a rejuvenation offgas. The gas and slurry mixture are passed into a vessel in which the gas (e.g. CO) is removed from the slurry. Further rejuvenation takes place when a rejuvenation gas (e.g. Hz) is bubbled into the slurry in the vessel. A gas removing downcomer removes gas from the slurry in the vessel before it is passed back into the reactor. The rejuvenation gas also acts as a lift gas in the lift pipe.

99101981 conditions

Nakata. T. et al. J. Ena. Gas Turbines Power, 1998, 120, (3), 474-480. In a gas turbine comb&tor in integrated coal gasification combined-cycle (IGCC) power generation, the ammonia contained in the coal-gasified fuel is converted to nitrogen oxides (Nor). The aim of this research was to obtain fundamental knowledge of fuel-NO, formation characteristics by applying reaction kinetics to gas turbine conditions. An instantaneous mixing condition was assumed in the cross-section of a gas turbine combustor; both gradual mixing and instantaneous mixing conditions were assumed at the secondary air inlet section. As the ammonia contained in the fuel decomposes in the primary combustion zone under fuel-rich conditions, HCN and other intermediates are formed. Under gradual mixing at the secondary air inlet, the conversion ratio from ammonia to NO, decreased with increasing pressure inside the combustor. The formation characteristics of fuel-NO, were affected by the condition of secondary air mixing. When compared with experimental results, these results showed approximate agreement.

Repowering with an integrated gasificationcascaded humidified advanced turbine (IG-CHAT) cycle

99101982

Freier, M. D. et al. Proc. Am. Power Conf., 1998, 60, (2), 602-607. An evaluation of several cases of an oxygen-blown fixed-bed coal gasifier combined with a cascaded humidified advanced turbine (IG-CHAT) power cycles was carried out to provide examples of repowering a typical USbased coal-fired power plant. Four gasifier cases were evaluated: (1) three circulating pressurized fluidized-bed combustor cases, (2) a bubbling pressurized fluidized-bed case, (3) an atmospheric circulating fluidizedbed case and (4) a refuelling case using a process-derived fuel and a natural gas-fired combustion turbine-combined cycle case. Only when the cost of natural gas increases to >$2.25-$2.50 per lo6 Btu did the IG-CHAT technology, along with the most competitive of the other advanced coalfired technologies, become competitive with natural gas-fired combinedcycles.

Research on agglomeration in coal gasifier with 99101983 twin fiuidized beds

Xione. Y. et al. Meitan Zhuanhua, 1997, 20, (2), 75-79. (In Chinese) Stud&d was the mechanism of agglomeration and defluidization process in a coal gasifier with twin fluidized beds. Optical microscope, X-ray diffraction (XRD) and thermogravimetric analysis were carried out on the samples of agglomerates which caused the defluidization in a coal gasifier with twin fluidized beds. The results showed that molten alkali and alkaline earth sulfates in coal, which are likely to form low-temperature eutectic because of their properties, were formed on the char’s surface and that the molten ash matrix on the char transferred to the surface of bed particles, caused them to form agglomerates as the result of random collisions between the bed particles coated with low-temperature compounds and caused the defluidization in the coal gasifier. Preventing the gasifier from agglomeration and defluidization was also discussed.

Resource conversion method of wastes 99101984 Fujinami, S. et al. Jpn. Kokai Tokkyo Koho JP 10 130,662 [98 130,662] (Cl. ClOJ3/00), 19 May 1998, JP Appl. 96/252,262, 4 Sep 1996, 7 pp. (In Japanese) In the conversion of organic wastes to energy resources the method comprises gasifying the wastes or required fossil fuels (e.g. coal) for generating synthesis gas and using the synthesis gas for power generation in accordance with the power needs and manufacture of synthetic fuels. The added amounts of fossil fuels can be adjusted by absorbing the variations of the quantity and quality of the wastes. Power generation can be achieved by using at least one gas turbine or steam turbine. The synthetic fuels, e.g. methanol, can be used for power generation during daytime. Gasifying comprises the low-temperature gasification of organic wastes and fossil

204

Fuel and Energy Abstracts

May 1999

Simulating laboratory scale

99101985

gasification of the gas, char gasification stage and

spouted bed gasifier

conditions

at

Slurry hydrocarbon synthesis process with muitistage catalyst rejuvenation

99101986

99107 987

Stability of Ni catalyst for methane reforming with CO2 and Hz0 under pressure

Lu, S. and Qiu, F. Yingyong Huaxue, 1998, 15, (4), 62-64. (In Chinese) This paper studies the reaction of methane with COz and Hz0 using the catalyst MCD-2. A 500 h continuous run was carried out under the following conditions: n-(CH4):n(C0z):n(HzO) = 1:1.5:0.9, methane space velocity 1000 h-‘, bed temperature 600-900°C and 0.6 MPa. At the end of this run, the porous structure, mechanical strength, content of active nickel, X-ray diffraction patterns and content of deposited carbon on the catalyst had not undergone any dramatic change and the activity of the catalyst maintained steady methane conversion of 292%. The CO content on the product gas was -4O%, while the Hz/CO ratio was -1.

99101988

Synthesis gas by combined reforming of natural

gas

Ch:n, G. Shiyou Huagong, 1998, 27, (8) 609-614. (In Chinese) The processes and methods of synthesis gas manufacturing from natural gas conversion are reviewed, with particular attention given to the combined steam reforming and partial oxidation approach. Methanol production via natural gas conversion is also discussed.

99101989

Synthesis of high polymers using C, compounds

Masuda, T. et al. Busshitsu Kogaku Kogyo Gijutsu Kenkyusho Hohohu, 1998, 6, (4), 159-167. (In Japanese) This paper outlines high polymer syntheses using syngas (CO + Hz) and its derivatives that can be obtained through steam treatment of diverse carbon resources which are available in sustainable volumes, such as waste plastics contained in city refuse, biomass that is a regenerative resource and coal and non-petroleum carbon resources. The syngas-aided synthesis of biodegradable plastics which is currently being studied by the authors is also introduced.

Temperature measuring device inside coal gasifier 99101990 Yoshida, K. et al. Jpn. Kokai Tokkyo Koho JP 10 237,466 [98 237,466], (Cl. ClOJ3/48), 8 Sep 1998, Appl. 97/45,504, 28 Feb 1997, 6 pp. (In Japanese) This paper describes a temperature measuring device inside a coal gasifier. The gasifier has a gasification chamber for the high-temperature reaction of coal and gasifying agent which contains a protective tube penetrated through the refractory material. The tube is easily inserted and removed. Where the protective tube penetrates the inner surface of the refractory, there is a cooling part surrounding it. The material of the cooling part corresponds to the temperature of slag-deposition prevention.