A kind of flue gas desulfurization and denitrification process method

Abstract

The invention discloses a flue gas desulfurization and denitrification process method. The method comprises the following steps: (1) spraying and washing flue gas containing NOx and SOx; (2) allowing a gas phase exhausted in step (1) to enter a desulfurization tower to be subjected to desulfurization treatment, wherein the desulfurization treatment adopts the ammonia desulphurization technology, part of NOx is removed during desulphurization, a low-concentration ammonia water desulfurization section is arranged at the upper part of the 0.5%-1.0%; (3) performing selective reduction denitrification reaction on gas exhausted from the top of the desulfurization tower. Compared with the prior art, the flue gas desulfurization and denitrification are combined organically, so that the overall effectiveness and economic efficiency of flue gas treatment are improved.

Description

technical field [0001] The invention relates to a treatment process for flue gas containing NOx and SOx, in particular to a desulfurization and denitrification process for boiler flue gas and refinery FCC flue gas. Background technique [0002] NOx (nitrogen oxides in flue gas, generally NO, NO 2 and N 2 A mixture of nitrogen oxides such as O) and SOx (sulfur oxides in flue gas, generally SO 2 and SO 3 mixture) is one of the main sources of air pollution. NOx and SOx in the atmosphere mainly come from exhaust gases from industrial processes related to combustion processes and exhaust emissions from motor vehicles and ships. [0003] Nitrogen oxides are collectively referred to as NOx, and the most harmful ones are: NO, NO 2 . The main hazards of NOx are as follows: (1) toxic to the human body; (2) toxic to plants; (3) can form acid rain and acid fog; (4) form photochemical smog with hydrocarbons; (5) destroy the ozone layer . [0004] In the atmosphere, SO 2 It will...

AI Technical Summary

Problems solved by technology

[0013] CN1895744A introduces a high-dust composite SCR flue gas denitrification process and denitrification catalytic reaction device. This SCR process is mainly aimed at NOx in power plant flue gas, and is not suitable for NOx in FCC flue gas. x governance

[0014] In the denitrification→desulfurization process in the prior art, NOx is first reduced to nitrogen, which consumes a lot of ammonia, and at the same time, NOx is not utilized at all

At the same time, in the follow-up desulfurization process, if the ammonia process is adopted, the problem of non-compliance of exhaust particulate matter cannot be solved