Method for synchronous desulfurization, denitrification, mercury removal and dust removal in bag type dust collector

Abstract

The invention discloses a method for synchronous desulfurization, denitrification, mercury removal and dust removal in a bag type dust collector. The method is characterized in that the bag type dust collector is taken as a reaction device for the synchronous desulfurization, denitrification, mercury removal and dust removal, manganese oxide is taken as an active material for the synchronous desulfurization, denitrification and mercury removal, and manganese oxide slurry or powder and an oxidation accelerator are jetted into a flue gas transmission pipeline; the manganese oxide can react respectively with sulfur dioxide, nitric oxide and gaseous mercury under the synergistic effect of the oxidation accelerator, so as to be converted into manganese sulfate, manganous nitrate and mercuric chloride particulate matters respectively; smoke, the unreacted manganese oxide as well as particulate products of the manganese oxide after being subjected to the desulfurization, denitrification and mercury removal are retained by a filter bag, so that a filtering layer is formed; and a material of the filtering layer is recovered at fixed period, so that the manganese oxide can be recycled. The desulfurization, denitrification, mercury removal and dust removal for coal-fired flue gas can be synchronously realized in the bag type dust collector in an integrated way.

Description

1. Technical field [0001] The invention relates to the field of air pollution control, in particular to a method for simultaneous desulfurization, denitrification, mercury and dust removal of flue gas. 2. Background technology [0002] Thermal power plants produce a large amount of SO in the process of high temperature combustion 2 , NO x , soot and other pollutants, nitrogen oxides in the air are the main source of fine particulate matter PM2.5, and thermal power plants are the largest emitters of nitrogen oxides. Therefore, it is imperative to denitrify power plants and reduce PM2.5 concentration without delay. Nitrogen oxides can also cause regional environmental pollution problems such as photochemical smog and ozone layer depletion. Thanks to SO 2 , NO x Emissions have caused acid rain in 81.6% of cities across the country, and increased severe weather such as smog across the country, which has seriously affected industrial and agricultural production, people's liv...

AI Technical Summary

Problems solved by technology

The shortcomings of this type of catalyst are: first, the cost of catalytic preparation is relatively high, and the toxicity is strong, and the workers must wear gas masks during installation. The service life of the catalyst is 3 years, and it is difficult to dispose of the catalyst after it fails; V 2 o 5 for SO 2 Oxidation to SO 3 The reaction is catalytic, and the resulting SO 3 with NH 3 Reacts with water vapor in flue gas to form NH 4 HSO 4 , when it is lower than its dew point (300 ~ 330 ℃), it will condense on equipment and pipelines, causing blockage and corrosion

The third is that the reaction temperature required for denitrification of this type of catalyst is relatively high (300-400°C), which is not suitable for the actual situation of flue gas desulfurization and low temperature after dust removal in existing power plants in my country.

The disadvantage of this technical solution is that the manganese oxide is not replaced and regenerated within the life cycle of the filter bag, and the manganese oxide is transformed into manganese sulfate due to the reaction with sulfur dioxide, which will quickly deactivate and lose the catalytic denitrification function

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