循环流化床锅炉低氮燃烧的技术改造实践

Technical Reform Practice of Low Nitrogen Combustion in Circulating Fluidized Bed Boilers

2014年,国家发展改革委、环境保护部、国家能源局联合下发了《煤电节能减排升级与改造行动计划(2014-2020年)》的通知,要求对我国现阶段600 MW及以上的燃煤机组进行改造,到2020年,实现大气污染物的排放符合国家规定的超低排放的极限值,即二氧化硫的质量浓度不超过35 mg/Nm^3,氮氧化物的质量浓度不超过50 mg/Nm^3,烟尘的质量浓度不超过10 mg/Nm^3。随着国家对环保力度的要求愈发严格,超低排放已涵盖所有燃煤机组。怎样降低锅炉烟气排放达到环保要求,成了重中之重。互太(番禺)纺织印染有限公司电厂通过与锅炉生产厂家研发人员的通力合作,针对现有的75 t/h循环流化床锅炉的状况,从氮氧化物生成的源头着手,进行低氮燃烧改造,目的是降低氮氧化物初始排放质量浓度。本研究通过理论知识和具体实践阐述如何降低N0X初始排放质量浓度的实施过程。

In 2014,the National Development and Reform Commission,the Ministry of Environmental Protection and the Energy Bureau jointly issued a notice on the“Coal Energy Saving and Emission Reduction Upgrade and Transformation Action Plan(2014-2020)”,which requires the coal-fired units of 600MW and above in China.After 2020,the emission concentration of atmospheric pollutants should meet the national limit of ultra-low emission,that is,the concentration of sulfur dioxide should not exceed 35mg/Nm^3,the concentration of nitrogen oxides should not exceed 50mg/Nm^3,and the concentration of soot should not exceed 10mg/Nm^3.With the strict requirements of the state for environmental protection,ultra-low emissions have covered all coal-fired units,and how to reduce the concentration of boiler flue gas emissions to meet environmental protection requirements has become a top priority.The company’s power plant cooperates with the boiler manufacturer’s R&D personnel to start the situation of the existing 75t/h circulating fluidized bed boiler.From 2015 to 2017,the four boilers will start from the source of nitrogen oxides and carry out low nitrogen.The purpose of combustion modification is to reduce the initial concentration of nitrogen oxides.This paper explains how to reduce the initial emission concentration of N0X through theoretical knowledge and specific practices.