CERAMIC FILTERS FOR THE HOT-GAS DESULFURI ZATION

Electricity generation from coal is expected to be mainly achieved by gas and steam power stations (GuD-Kraftwerke) in which coal gases serv e as fuel. Precondition for the operation of a gas turbine with coal g as is the preceding scrubbing of the gas from aggressive gaseous compo nents, for example H2S, at high temperatures of about 550-degrees-C an d pressures up to 20 bar. A central problem at the cleaning are the ho t-gas filters. For these, ceramic filters were developed on the basis of ceramized polyurethane sponges, loaded with zinc oxide and used for desulphurization. The regeneration takes place in the air current. Ma terial-scientific investigations for the production, for the structure of the ceramic filters, as well as for the mutual reaction between th e ZnO-loaded ceramic filters and the H2S-parts of the coal gas and of the sulphurized ceramic bodies. respectively, and the oxygen in the ai r provide hints for the life-duration of the filters. The results of t he investigation show that ZnO-loaded ceramic filters are suitable for the bot-gas desulphurization of reducible coal gases and that they ca n be regenerated well.