Flue gas desulphurisation

摘要

This process enables any low-dust flue gas to be scrubbed sulphur-dioxide-free with a high degree of efficiency and flue gas heat originally necessary for SO2 dispersion to be extracted in a utilisable manner and to be used. The residual heat portion still necessary for the energetics of the process is characterised by the temperature difference of 15 DEG K above the temperature of the purified exhaust gas. Crystalline and thus marketable ammonium sulphate is generated in this case. The high degree of efficiency with simultaneous low heat requirement is made possible by a circulation process in which scrubbing is carried out by ammonium sulphite solution at low temperature, the oxidation to give ammonium sulphate is carried out at a higher temperature in the same tower without steam generation and recooling and the further supply of ammonia, ammonium sulphate precipitation and separating off ammonium sulphate takes place in a single, fully integrated material-loss free and heat-loss free cyclic process. The process has the advantage of high availability, high efficiency, low operating and capital costs and owing to the utilisation of thermal energy and ammonium sulphate fertiliser, it comes into the area of a profit-making industrial method.