Desulfurization and denitration system and method combining sintering flue gas circulation with ozone pre-oxidation

Abstract

The invention provides a desulfurization and denitration system and method combining sintering flue gas circulation with ozone pre-oxidation. The system includes an ozone preparation device, a desulfurization reaction device, a denitration reaction device and a sintering flue gas circulation device; ozone is used for primary ozone pre-oxidation treatment of flue gas before a desulfurization reaction in a main flue of a sintering machine and secondary ozone pre-oxidation treatment of flue gas before a denitration reaction; the desulfurization reaction device is used for desulfurization treatment and primary denitration treatment of the flue gas; the denitration reaction device is used for secondary denitration treatment of the flue gas; and the sintering flue gas circulation device can supply oxygen to the high-temperature flue gas for recycling the flue gas. The desulfurization and denitration method includes the steps of sintering flue gas circulation, desulfurization and denitrationreactions after ozone pre-oxidation treatment, and discharge of flue gas. The system and method provided by the invention can improve the flue gas circulation rate to 30% or more, improve the denitration reaction rate, and reduce the use amount of a catalyst and prolong the service life, so that the NOx emission reaches or exceeds ultra-low emission of flue gas.

Description

technical field [0001] The invention belongs to the technical field of flue gas desulfurization and denitrification and waste heat utilization in the iron and steel industry, and in particular relates to a desulfurization and denitrification system and method using sintering flue gas circulation combined with ozone pre-oxidation. Background technique [0002] The iron and steel industry is a high-pollution industry. The iron ore sintering process itself produces a lot of smoke. In addition, because the air leakage rate of the domestic sintering machine is as high as 40%, a considerable part of the air does not pass through the sintering material layer and directly enters the subsequent flue gas treatment device. Therefore, the amount of sintering flue gas is very large. For example, a 360m 2 When the sintering machine is in normal production, the amount of flue gas emitted is as high as 2.16 million cubic meters per hour. In addition to the large amount of sintering flue g...

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Problems solved by technology

[0008] The purpose of the present invention is to provide a desulfurization and denitrification system and method combined with ozone pre-oxidation of sintering flue gas circulation, to at least solve the problem of large catalyst consumption and short service life in the current flue gas desulfurization and denitrification process; large flue gas treatment capacity, It leads to the consumption of a large amount of fuel for flue gas heating, thereby increasing the investment and operating costs of desulfurization and denitrification devices; in addition, the denitrification effect is difficult to meet the ultra-low emission standard.

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