焦化烟气活性焦低温脱硝工艺与反应器开发

为了开发适用于焦化烟气的干法脱硫低温脱硝技术，在现有活性焦脱硫脱硝技术的基础上，针对焦化烟气低硫高硝、排烟温度低、湿度高等特点，选取一种商用活性焦，在试验装置上分别研究了空速、温度、氨氮比和湿度等对活性焦脱硝性能的影响，在此基础上设计了左右并联式、错流移动床反应器结构形式，并根据理论计算和结构设计模型完成反应器图纸设计，建成60万t/a焦炉配套的活性焦干法脱硫低温脱硝工业装置，并在工业装置上开展了72h工业性试验，验证实验室工艺与反应器设计可行性。结果表明，活性焦脱硝适宜的工艺参数条件为：空速300h-1，反应温度140℃，氨氮比1.3，烟气湿度不宜超过16%|以某焦化厂烟气为例，进行了反应器尺寸理论计算，设计出15万Nm3/h烟气量处理能力的反应器尺寸为8m×33m×4m|工业性试验的烟气温度、氨氮比、湿度均以实验室结果为基准开展试验，烟气平均进口温度约135℃、氨氮比1～1.1∶1、烟气平均湿度12.5%，在此条件下，装置脱硫、脱硝效率分别为99%和89%，在基准氧含量为8%时，SO2和NOx平均排放浓度分别为4mg/m3和92mg/m3，满足焦化烟气超低排放指标要求。

Process and reactor of coking flue gas denitration at low temperature by activated coke

In order to develop dry desulfurization and low-temperature denitrification technology for coking flue gas, effects of air speed, temperature, ammonia nitrogen ratio and humidity on the denitrification performance of commercial active coke were studied. The structure of reactor was designed, and reactor size was calculated by calculation model. The results show that the suitable process parameters for denitrification of activated coke as following: space velocity 300 h-1, reaction temperature 140 ℃, ammonia nitrogen ratio is 1.3, flue gas humidity no more than 16%. Aiming at improving desulfurization and denitrification efficiency of activated coke reactor, the structure of reactor is left-right parallel and cross flow moving bed reactor. Take flue gas of coking plant example, activated coke desulfurization and denitration reactor with capacity of 150000 Nm3/h is designed with size of 8 m×33 m×4 m.