Objective
The process is based on the use of a novel spouted fluidised bed system, designed to utilise a wide range of coals in terms of swelling and size grading and produce a gas low in tar, sulphur and dust. The aim of the project is to construct, operate and evaluate a 0. 5 T/h fluidised bed gasification plant for the manufacture of a low calorific value fuel gas for industrial application.L%
Successful developments have been achieved in all areas of the plant. Coal conversion of 70% on a mass basis have been attained with a gas calorific value of 3. 8 MJ/m3. Start up operating and shut down procedures have been developed. Several coals have been tested giving similar performances. Sulphur retention by the addition of limestone indicated that 80% of sulphur which otherwise would be released in gas can be retained. Alternative gas cleaning techniques have been evaluated. It was found that a high efficiency cyclone was insufficient to meet emission requirements. Moreover early promise has been shown by a bag filter producing a dust-free gas. Burner designs have been developed for combustion of the low calorific value over a range of operating conditions.
The pilot plant comprises facilities for coal and limestone feeding, gasification, gas cleaning and combustion. Coal is fed to the gasifier either overbed using a screw feeder, or underbed by pneumatic injection. The gasifier is fluidised on a mixture of air and steam and operated slightly above atmospheric pressure at a nominal bed temperature of 980 deg. C. and fluidising velocity of 2 m/s. Fuel gas of low calorific value (4. 0 MJ/m3) is produced with minimal tar content. Most of the sulphur which would otherwise be released in the gas can be retained in the bed by the addition of limestone. Gas cleaning is performed in one of the two alternative system, which will be evaluated to ensure environmental and user standards are met. Information on the gas combustion characteristics will be obtained by burning some of the gas in an existing test furnace facility.
Work on the project started in January 1981 with the appointment of an engineering contractor (Courtaulds Engineering) tocarry out the design and installation phases of the contract. This work was completed in April 1985. Cold commissioning of the plant was completed by August 1985. By the end of the contract six operational runs had successfully been completed.
Topic(s)
Call for proposal
Data not availableFunding Scheme
DEM - Demonstration contractsCoordinator
GL52 4RZ Gloucester
United Kingdom