Integrated purification method and device for CO and NOx removal of gas boiler

Abstract

The invention discloses an integrated purification method and device for CO and NOx removal of a gas boiler, and belongs to the field of treatment of gaseous pollutants. A return flue of the gas boiler is connected with a gas inlet of a catalytic reaction device through a boiler flue gas outlet, and a gas outlet of the catalytic reaction device is connected with a fan through a waste heat recoverysystem; a urea solution injection device (15) is arranged in the return flue, and the urea solution injection device is connected with a urea storage tank through a metering device and a control device; a guide plate, a CO oxidant layer and a denitration catalyst layer which are all vertical to a shaft are arranged in the catalytic reaction device sequentially to form a multi-stage reactor. The injection point of a denitration reductant is located in the return flue of the gas boiler within 300-500 DEG C, urea decomposition is facilitated, and decomposition product NH3 is uniformly mixed in arear flue section, CO and NOx are simultaneously removed by a CO oxidant and a denitration catalyst, denitration efficiency of the catalyst is improved, service life of the catalyst is prolonged, andclean and energy-saving emission is finally realized.

Description

technical field [0001] The present invention is based on the fact that a certain amount of nitrogen oxides (NO x ) and carbon monoxide (CO) and other gaseous pollutants, and on the premise that there is no corresponding CO emission standard, to provide a simultaneous removal of CO and NO in the flue gas x 1. A purification method and device for realizing ultra-low emission, belonging to the field of gaseous pollutant treatment. Background technique [0002] With my country's economic development and the adjustment of energy structure, and natural gas has the advantages of high calorific value, cleanness, and no waste residue after combustion compared with coal, oil and other energy sources, gas-fired boilers will become the direction of future promotion and development. However, gas-fired boilers inevitably produce NO during operation. x And air pollutants such as CO produced by insufficient fuel combustion. Among them, NO x It is the air pollutant that involves the most...

AI Technical Summary

Problems solved by technology

Among them, NO x It is the air pollutant that involves the most environmental problems. It is the main precursor of the greenhouse effect, acid rain, ozone layer destruction, water eutrophication, photochemical smog and smog, and CO is a common toxic and harmful gas. At the same time, CO is a clean fuel. Direct emissions not only waste energy, but also negatively impact human health and the atmosphere

[0003] In the situation of air pollutant emission limits and environmental protection law enforcement are becoming increasingly strict, combined with the characteristics of gas boiler flue gas components, coupled with gas boiler flue gas removal of CO and NO x The integrated purification method and device have not yet been practically applied in the market. Therefore, it is necessary to develop a synergistic method for the removal of CO and NO in flue gas. x Integrated control technology is of great significance to the clean emission of gas boilers

At present, there are no literature and patent reports on the synergistic removal of CO and NO from gas-fired boiler flue gas x Technical process of gaseous pollutants such as

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