Air Blown Fluidised Bed Gasification of high ash Indian Coals -BHEL's experience in a 168 TPD PFBG

摘要

Bharat Heavy Electricals Limited (BHEL), India has installed a 6.2 MW IGCC plant in 1989, with a moving bed gasifier. Having established the feasibility of IGCC for high ash Indian coals and understanding the limitations of the moving bed gasifier, BHEL added a Fluidised bed gasifier in 1996. This paper gives a brief description of the Pilot. Scale IGCC Demonstration plant and BHEL's experience in gasification of the coals along with details of various systems incorporated and tested and the parametric variation studies during the tests to enhance the performance of the gasifier. The extent of improvement in carbon conversion with fly ash recycling adopting a non mechanical (seal pot) recycle system are presented. The effect of some of the parameters like the temperature of operation of the fluidized bed and the temperature of the air used for fluidisation and reaction on gas composition are detailed. Based on the experience, BHEL is working on a scale up design to 182 MW capacity. The basic details of the same are also presented.