Process for the purification of flue gases from heating and purification plants for carrying out the process

摘要

PCT No. PCT/DK81/00118 Sec. 371 Date Aug. 23, 1982 Sec. 102(e) Date Aug. 23, 1982 PCT Filed Dec. 22, 1981 PCT Pub. No. WO82/02151 PCT Pub. Date Jul. 8, 1982.By a process of cleaning flue gases, both solid particles and nitrogen oxides and sulphur dioxide are removed from the flue gas prior to the discharging into the atmospheric air. In order to ensure that almost all the content of sulphur dioxide and nitrogen oxides is removed from the flue gas, said flue gas is initially carried through a shower of aqueous liquid and subsequently through a heat exchanger, in which its temperature is lowered to about 20 DEG -30 DEG C., and then through a film of alkaline liquid, and finally through a second shower of aqueous liquid to pass a sulphuric acid neutralizing liquid in a container before the discharging into the atmospheric air. As a result a simultaneous possibility of utilizing the heat of the flue gas is ensured by means of the heat exchanger. A cleaning plant for carrying out the process comprises an apparatus (2), through which the flue gas cleaned of solid particles is carried. When seen in the flow direction, this apparatus comprises a first flue scrubber (8), in which the flue gas is subjected to a shower of liquid, a two-step heat exchanger (9, 10) permitting a reduction of the temperature of the flue gas to 20 DEG -30 DEG C. After the two-step heat exchanger (9, 10), the apparatus (2) comprises a rotating, conical disc (11) providing a film of milk of lime, through which the flue gas is forced to pass during the continuous flow through the apparatus. After this film of milk of lime, the flue gas passes a shower of liquid emitted from a second flue scrubber (14), and upon said scrubber the flue gas is forced to pass a limy liquid in a container (15).