The development of improved gas filtration systems for emission control in the case of small solid fuel combustion units
Three different types of gas filter were tested: a ceramic fiber mat, a ceramic foam and a ceramic honeycomb. Three different pilot test rigs were used : an open fireplace (test rig No. 1), a closed appliance (test rig No. 2) and a specially designed "smoke-eating" appliance which can be converted from an open fire to a closed fire by attaching a "fire front" (test rig No. 3). Most testwork was carried out using peat briquettes or Polish coal as fuel. Separate laboratory studies established that for the rapid (uncatalysed) combustion of smoke particulates, temperatures of at least 500 C (for peat smoke) or 600 C (for coal smoke) were necessary. In test rig No. 1 it was impossible to develop a system which would result in these kinds of temperatures continuously. Rapid blockage of filters resulting in gas and smoke spillage was unavoidable. In test rig No. 2 the conflicting demands of gas flow, filter efficiency and rapid self-cleaning of filters by smoke combustion could not be reconciled. In test rig No. 3 satisfactorily low smoke emissions (< 5 g/h) were measured when used in the "closed appliance" mode. This was due to appliance design and not to the introduction of a filter system. This is recommended as the most promising route to be followed in addressing this problem. Studies carried out on the chemical composition of smoke revealed small but significant amounts of polyaromatic hydrocarbons in coal smoke (about 0.3% w/w) and peat smoke (about 0.16% w/w).
Bibliographic Reference: EUR 12790 EN (1990) 55 pp., MF, ECU 4
Record Number: 199010757 / Last updated on: 1994-12-01
Original language: en
Available languages: en