摘要
本文介绍某电厂对其循环流化床锅炉进行环保升级的案例,分别从现有系统状况和改造方案等两方面进行了论述。某电厂现有4x75t/h循环流化床锅炉,烟气中氮氧化物、二氧化硫及粉尘等不能满足国家最新的超低排放标准,为此对其进行环保升级改造,改造后烟气中氮氧化物、二氧化硫及粉尘的排放浓度分别低于50、35、5mg/Nm^3。脱硝采用SNCR提效改造+炉内SCR(尾部烟道合适位置处布置一层)+COA(低负荷保障手段);脱硫除尘采用静电除尘器(预除尘)+循环流化床半干法脱硫(附属布袋除尘器);消白采用烟气直接升温,加热介质为低压蒸汽。
This paper introduces in detail the case of environmental protection upgrading of circulating fluidized bed boilers in a power plant, and discusses the existing system status and improvement scheme. The existing 4 x75 t/h circulating fluidized bed boiler in a power plant can not meet the latest national ultra-low emission standards, such as nitrogen oxides, sulfur dioxide and dust in flue gas.Therefore, the environmental protection upgrading of the boiler is carried out. The emission concentration of nitrogen oxides, sulfur dioxide and dust in the flue gas is lower than 50, 35 and 5 mg/Nm^3 respectively. SNCR efficiency improvement + SCR(one layer in the tail flue) and COA(low load safeguard means) are adopted for denitrification;electrostatic precipitator(pre-precipitator) and circulating fluidized bed semi-dry desulfurization(auxiliary bag precipitator) are used for desulfurization and dust removal;flue gas is heated directly and low pressure steam is used for heating medium.
