Coal & Gas Technology Division
Coal & Gas Technology group at the Indian Institute of Chemical Technology, Hyderabad had been engaged in the development of Indigenous processes for the rational utilization of the locally available low-grade coals, since its inception. Low Temperature Carbonization process for producing domestic coke was perhaps, one of the first and the largest successful effort in this direction that could be commercialized. A 900 tonnes coal per day Commercial LTC plant based on the IICT technology went in to operation as early as by 1978 at the Coal Chemicals Complex of the Singareni Collieries Co., Ltd., Ramakrishnapuram, AP, producing the ‘Sicco Coke®’ and operated uninterrupted for over three decades till it was recently shut down due to growing problems in the marketability of the product. Extensive work done on various briquetting aspects including the development of different binders, briquette strength, etc., led to transfer of technology to small, medium and large-scale industry alike that included commercial use of our technology in the Coal Chemicals Complex of SCCL making the smokeless SICCO coke briquettes.
IICT has gained leadership position in Energy R&D area from the expertise it acquired through hands-on experience on gasification of coal, an initiative taken as early as in the mid-sixties. A 1t/h pilot plant based on the moving bed gasification was installed and during the extensive trials on the 24 tpd pilot plant, 2900 tons of coal was gasified at pressures up to 24 kg/cm2 in about 21 test campaigns spanning over seven years from 1983-90, logged 4600 hours of operation and valuable Process data on gasification characteristics of the low-grade Indian non-caking coals collected both on Air-blown & Oxygen-blown modes of operation.
Elaborate experimental programme in this UNDP-assisted project included parametric optimization studies and testing of six different low-grade Indian coals & a lignite, Special studies on development of a mathematical model and its validation, Elucidation of gasification reaction kinetics through studies on coal reactivity in a Thermo-Gravimetric Analyzer(TGA), measurement of axial temperature profile in the fuel bed, Residence Time Distribution for flow of solids down the reactor, Scale-up studies for application in power generation through Integrated Gasification Combined Cycle(IGCC), Participation in making a comparison of nine different IGCC technologies that were being developed abroad that culminated in the preparation of a Techno-Economic Feasibility Report (TEFR) for a 600MW IGCC plant when using a very high ash Coal from North Karanpura, Jarkhand for comparing four IGCC processes including the indigenous Moving bed process with NTPC's conventional thermal power plant of same capacity in 1992.
In line with the activity on hand, i.e., Coal gasification for IGCC power generation, it was prudent that, IICT take up work on the Gap areas in IGCC technology and accordingly, process development for Hot Cleanup of Coal-derived Fuel Gas at 850oC & 20kg/cm2 for removal of dust by Filtration through Ceramic Candle Filters and Sulphur compounds (H2S & COS) by Chemisorption on mixed metal oxide sorbents was successfully done using simulated gas mixtures in 2005. Desulphurization done in a dual bed adsorber resulted in recovery of the removed sulphur as elemental Sulphur by-product. The project was successfully completed in July’06.
Apart from process development, physico-chemical characterization of coal samples received from the industry is being done under ISO-9001:2008 surveilance, commercially offering the services to clients for various analyses such as the Proximate, Ultimate, Calorific value, Gray-King Carbonization Assay, Hardgrove Grindability Index, Forms of Sulphur, Ash Fusion characteristics, etc., since the very inception and is being continued. Currently the group is being led by shri B. Madhusudhan.