| 摘要 |
The invention relates to a method for the denitrification of bypass exhaust gases (105, 205, 305) in a plant for producing cement clinker, the plant comprising in the gas flow direction a rotary kiln (102, 202, 302), and said rotary kiln (102, 202, 302) being connected to a calcinator (107, 207, 307) for the deacidification of raw meal or to a rotary kiln riser shaft via a rotary kiln inlet chamber (104, 204, 304), and the bypass exhaust gas being drawn off in the region of the rotary kiln inlet chamber (104, 204, 304). The method according to the invention comprises the following steps: cooling the bypass gas (105, 205, 305) to a temperature between 260°C and 400°C in a cooling device, injecting an ammonia-, urea- and/or ammonium-containing substance into the cooled bypass gas (112, 21, 312), introducing the bypass gas (112, 21, 312) that has been mixed with an ammonia-, urea- and/or ammonium-containing substance and cooled into a ceramic filter system (114, 214, 314), in which any halide and sulfate of the alkali metals and alkaline-earth metals precipitated during cooling of the bypass gas (112, 21, 312) is filtered out, and any nitrogen oxide not yet reacted by the ammonia-, urea- and/or ammonium-containing (NH4 +) substance is chemically selectively reduced over a catalytic converter (116, 216, 316) which is located in the ceramic filter system (114) and/or which is located directly downstream of the ceramic filter system (214, 316). |
