| Abstract |
An effective, simple handling and efficient system for mainly medium and small sized power plants, district heating plants, garbage incinerators etc. up to 300 MW electric output could be developed. For the 80 to 90% decrease of the acidic components in the flue gas the 'Spray Drying System Duesseldorf' has been applied in the meantime for more than 25 units of different sizes and a total of more than 3 million cubicmeters. The combination of a lignite coke filter and catalyst as a multistage filter coupled with the spray drying system, filters the rest of solids, adsorbes (the rest of) the acidic components, the vaporous heavy metals, the carbon hydrates etc. After adding ammonia to the flue gas the coke coal then works as a catalyst for the NO/sub x/-reduction at temperatures of about 80 to 100/sup 0/C, that means without any expensive reheating, as known from the metal type catalysts. The lignite coke is an uncomplicated, inexpensive material, which will be burned as fuel after use. The coke consumption only depends on the amount of the acidic components in the flue gas (i.e. efficiency of the scrubber). The results measured up to now have shown that with lignite coke (1) the flue gas from a coal-fired boiler can be completely desulfurized, whereby SO/sub 2/ loadings of the coke of 10-15% are to be achieved, (2) with the flue gas remaining in the coke for a period of 15-20 seconds it is possible to achieve NO/sub x/ reductions of 80-90%, (3) the NO/sub x/ content in the clean gas varies between 150 and 250 mg/m/sup 3/n. (ERA citation 14:021980) |
