04598 Gasification and char combustion reactivities of Daw Mill coal in wire-mesh and ‘hot-rod’ reactors

04598 Gasification and char combustion reactivities of Daw Mill coal in wire-mesh and ‘hot-rod’ reactors

03 Gaseous fuels (derived gaseous fuels) generation in the Krahi coal mining area. The project team has developed a detailed methodology to determin...

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03

Gaseous fuels (derived gaseous fuels)

generation in the Krahi coal mining area. The project team has developed a detailed methodology to determine the technical feasibility. environmental acceptability, and commercial economic potential of UCG at a selected site. Hydra-geological conditions of the coal seam and surrounding strata are initially determined and in the assessment. The methodology and current project status are discussed in this paper. 97104587

Comparative waste materials

study

of

biogas

production

from

with a space between the slag tap and water. With the design of the inclined downward injection of the burners of powdered coal and char and opposite light-oil burner, the air flows upwardly with a greater contour line such that slag particles drop to the wall hy centrifugal force and through the tap. which are then cooled by water and discharged.

97104594 Environmental performance of an oxygen-blown entrained-bed coal gasification pilot plant

Euzen, J.-P. et al. Eur. Pat. Appl. EP 794,239 (Cl. CIOG2/00), IO Sep 1997, FR Appl. 9,6/2,91 1. 8 Mar 19Y6, 9, pp. (In French) The preparation of Cs_,,, hydrocarbons from synthesis gas using a FischerTropsch catalyst in apparatus consisting of 2-3 catalyst beds and an intermediate mixing zone. Methane selectivity is 4.6% and 8%92% for Cs+ hydrocarbons.

Ueda, F. et al. Kagaku Kogakrr Ronhumho, 1997, 23. (I). 1X-27. (In Japanese) Four coals were selected to study the hehaviour of their trace elements during entrained-bed coal gasification in a 50 ton/d plant (HYCOL). The heha;our was characterize2 by their distribution in’solid, water and gas. More volatile elements were present in dust from water scrubbing (cake) than in slag from the gasifier. The cake contained submicron particles. Results from leaching tests on slag and cake showed that water emissions were below the regulatory limit. More than 90% of the coal sulfur was liberated and converted to HzS and COS in the syngas and a few percent of the coal nitrogen converted to NH2 and HCN. Since almost all NH; and HCN can he removed by water scrubbing. their contents in syngas were Icss than a few ppm. The scrubbing system will remove a significant proportion of submicron particles and nitrogen compounds from syngas. In order to obtain a precise understanding of their hehaviour. the trace elements in syngas and the elements possibly accumulated in the plant devices must he measured directly.

Development of load and pressure controler for the 97104589 200 tons per day entrained flow IGCC pilot plant in Japan.

Experimental study 97104595 gasifier with a twin-fluidized-beds

different

Mandal, T. and Mandal, N. K. Ener~ Conven. Mgmt, 1997, 38, (7), 67Y683. The biogas generation capacity of each mixture and its individual components of various categories of waste materials was determined via experimental studies. Hence, the best waste material, that can produce the maximum amount of biogas from each category of waste materials, has been found at a specific temperature of 37°C.

Conversion of synthesis 97104588 the presence of a liquid phase

gas into hydrocarbons

in

Nagata, K. ef al. Adv. lnstrum. Control, 1996, 51, (2), 1307-1319. From the viewpoint of the power generation mixture in Japan, nuclear power plants will continue to be operated to meet the base load, while integrated coal gasification combined cycle (IGCC) power plants will be required to serve as thermal power plants. They will cover the middle load as is the case with conventional thermal power plants. In terms of operational performance, therefore, IGCC power plants will need to be able to follow a wide range of load demand at high speed. For this purpose, a load and pressure controller was developed and tested during the operational research on a 200 tons/day entrained flow ICCC pilot plant at the Nakoso Power Station by the Engineering Research Association for IGCC Power Systems (IGC Association) under the trust of New Energy and Industrial Technology Organization (NEDO). The development of the load and pressure controller and the results of the control test carried out to check the load follow capability of the pilot plant are reported. In addition, some information on the simulation study also being conducted is provided.

Developments in Fischer-Tropsch technology 97104590 Stud. Surf. Sci. Catal., 1997, 107, (Natural Gas Conversion IV), Jager, B. 219-224. SSPD and SAS reactors are discussed. The integrated Fischer-Tropsch process with syngas production is also presented. Direct flow solid bed gasification gas and heat recovery from wastes 97104591

reactor

for fuel

Kuntschar, W. et al. PCT Int. Appl. WO 97 32.945 (Cl. (X033/26), 12 Sep 1997, DE Appl. 19,608,826, 7 Mar 1996, 62 pp. (In German) A gasification reactor for gasifying organic solids of high ash content and tending to form slags was constructed. The reactor comprises a solids storage chamber bounded at the base by a grate, and a product gas line for discharging the product gas. The solids storage chamber has an oxidation zone with an air and/or oxygen feed, To create a continuously operating gasification reactor, the reactor should be provided with a slag-separation device and a discharge mechanism with which the separated slag can be removed from the reactor, and with a ring duct around the periphery for the oxygen supply. The invention is also directed at advantageous uses of the gasification reactor.

Ecological indexes in a power block with a 97104592 module for oxygen gasification of coal-dust fuel and steamgas equipment Bogacheva, Russian) The paper module for gas. Lower sulfur, are

97104593

T. M. and Petukhov, V. I.

E/&r.

Stn., 1996, (I l), 32-36.

(In

presents a 500 MW power block which includes a gasification 280 t/h of raw fuel with the production of 329,000 m’ih synthesis emission levels of the technology, especially removal of ash and discussed.

Entrained-bed

coal gasifier

Kate, S. and Fukuda, H. Jpn. Kokai Tokkyo Koho JP 09,227,879 197,227,879] (Cl. ClOJ3/46), 2 Sep 1997, Appl. 96/31,X90, 20 Feb 1996, 6 pp. (In Japanese) Introduces an entrained-bed coal gasifier with improved collection efficiency of melt slag and scattering prevention. It comprises at least one powdered coal burner with inclined downward injection on the side wall of the combustor zone, a pair of char burners oppositely disposed above the powdered coal burner and symmetrical to the flow of the powdered coal burner. A light oil burner is situated on the opposite side of the powdered coal burner with a light-oil lighting torch at a right angle to the light oil burner. A slag tap is provided at lower part of the powdered coal burner

398

Fuel and Energy Abstracts

November

1997

on

thermal

balance

in the

Li, 2. et al. Ranshao Kexue Ytr Jishu., 1996. 2. (I), IS-22. (In Chinese) In a middle scale hot-mode experimental apparatus an experimental study concerning ignition and heating of a twin-fluidized-hed gasifier. tcmperature profile of the twinbed as well as heat transfer hetween the two hcds. was made. The results were used to calculate the solid particle circulating rate between the beds. In this paper various variables effecting on the operatton of the gasifier are discussed. This study provides :I hasIs for further research.

97104596

Fractal concepts

in modelling

of char gasification

Hu, G. et al. Huagong Xuehao, 1997, 48, (4), 457-464. (In Chinese) An analysis of the interactions between transport, reaction, pore morphology and evolution process are presented in a fractal pore model. The\e local fractal pores are the constituents of the pore network of char particles. The Bethe network is used to describe the pore space topology of the medium. This approach provides a natural framework for characterization of the geometrical structure of the pore andmodelling of pore opening. enlargement and coalescence in the evolution of porosity and internal accessible surface area with the process of char gasification. This study also considers the loss of solid fragments by percolation. So it is applicahlc to modclling the char gasification process in an industrial gasifier.

97104597 cycle

Fuel behaviour

studies in the air-blown

gasification

Paterson, N. Fuel, 1997. 76, (l3), 1319-1325. An overview of the air-blown gasification cycle (ABGC) development programme is given. Pilot-scale investigations of the fuel flexibility of the gasification process have been conducted. The performance and operability of the gasifier with a selection of world coals is discussed. The Tuccessful development of the components of the ABGC is nearing completion. although some outstanding areas need further investigation.

97104598 Gasification and char combustion reactivities Daw Mill coal in wire-mesh and ‘hot-rod’ reactors

of

Lim, J.-Y. et al. Fuel. 1997, 76, (13), 1327-1335. Daw Mill (UK) coal was investigated for its pyrolysis and CO:-gasification behaviour of using wire-mesh (WMR) and fixed-bed ‘hot-rod’ (HRR) reactors. Experiments were performed at pressures between 0.1 and 3 MPa at 850 and 1000°C. These reaction conditions reflect those of novel power plant technologies (e.g. ABGC) in which coal gasification and char combustion reactivities are relevant to design and operation. All experiments used untreated coal samples rather than pre-prepared chars. CO: gasification reaction rates were directly calculated from the difference between mass loss in pyrolysis and during gasification in COZ. Combustion reactivities of the chars from these experiments were determined in an atmospheric pressure thermogravimetric balance. The partitioning of the original sulfur and nitrogen contents between the volatiles released in the gasifier and the char transferred for combustion in the CFBC were determined. The reactivities of four other coals were also tested at 1000 C and 2 MPa. A straightforward relationship of declining pyrolysis mass loss with increasing rank was discovered. However, even within the limits of the small number of samples tested, considerable scatter was found in the reactivities of middle-rank coals, probably due to a combination of structural factors, including differences in char pore structure. catalytic effects of mineral matter components and differences in the inherent reactivity of the carbonaceous matter. The percentages of coal nitrogen and sulfur retained in the residual chars generally declined with increasing pressure; reactive gases appear to remove char nitrogen more efficiently. suggesting that pyrolysis experiments may not he a good guide to char nitrogen partitioning in gasification and combustion.