For PM emission control in very high temperature exhaust streams ( >600ºC ), such as gasification, pyrolysis and incineration, traditional bag filters following temperature exchangers, ceramic filters, or scrubbers are used as end stage dedusters.
For most arrangements, a primary high temperature separator, namely a cyclone, is important to reduce as much ash and char as possible. A good efficiency is important to reduce concentration of solids to the final stage dedusters, avoiding plugging of scrubbers and damaging of filters.
Most arrangements have considerable investment and operation costs. Traditional bag filters imply the frequent change of bags and a high investment in temperature exchangers. Ceramic filters can withstand high temperatures but have a considerable pressure drop, typically up to 300mm w.g., gradually increasing due to clogging of the pores. The long-term durability and cracking risk (mainly during cleaning) of the elements are also critical.
Client's needs include an efficient and robust cyclone pre-separator and a very high efficient final stage dedusting system, which can operate at high temperatures with low maintenance/operating costs.