A limestone-gypsum wet flue gas desulfurization and denitrification additive

Abstract

The invention provides an additive for limestone-gypsum wet flue gas desulfurization and denitration process, which belongs to the flue gas treatment field. The additive comprises amines 40-60 wt.%, organic acids 30-45 wt.%, and polymeric organic carboxylate 10-30 wt.%. The amines can directly react with sulfur dioxide acidic gas to form ammonium sulfite, thus realizing desulfurization. The amines can react with nitrogen oxides to form nitrogen gas, thus realizing denitration. The organic acids and polymeric organic carboxylate can promote the dissolution of limestone for reducing the usage amount of limestone, promote pH buffering capability of limestone slurry, prevent rapid pH decrease during the absorption of sulfur dioxide, inhibit formation of calcium sulfite soft scale, and prevent plugging of demister. Compared with the existing limestone method, this invention has increased desulfurization efficiency (by 5-10%) and increased denitration efficiency (by above 50%) under the same liquid-gas ratio condition.

Description

technical field [0001] The invention belongs to the technical field of flue gas purification, and in particular relates to an additive used in limestone-gypsum wet flue gas desulfurization and denitrification. Background technique [0002] Air pollution control has become the theme of environmental governance in today's era, and the main indicator of atmospheric substances is carbon dioxide (SO 2 ) and nitrogen oxides (NO x ). The Ministry of Environmental Protection and the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China jointly issued the "Emission Standards of Air Pollutants for Thermal Power Plants" which will be implemented on January 1, 2012. SO 2 Emission limit implementation 200mg / Nm 3 , NO x Emission limit implementation 100mg / Nm 3 . Stricter than the existing GB13223-2003 emission limits, especially for NO x emissions will be used as mandatory indicators. [0003] At present, the methods of simulta...

AI Technical Summary

Problems solved by technology

At present, coal-fired power plants across the country are facing the dilemma of difficulty in purchasing coal, poor coal quality, especially high and fluctuating sulfur content in coal-fired coal. The desulfurization system is often operating under abnormal conditions, and the desulfurization efficiency is low.