燃煤工业锅炉飞灰回用鼓泡(乳化)湿法脱硫除尘一体化系统研究

Research on integrated bubbling(emulsification)wet desulfurization and dust removal system for reuse of fly ash from coal-fired industrial boiler

针对目前工业锅炉石灰石湿法脱硫系统易堵塞、运行费用高等问题,开发了一种新型燃煤工业锅炉飞灰回用鼓泡(乳化)湿法脱硫除尘一体化系统,改变传统粉煤灰脱硫仅作为脱硫剂载体直接喷入烟道的利用方式,通过提纯粉煤灰中Ca^(2+)离子制成碱性浆液实现粉煤灰湿法脱硫,不需添加其他脱硫剂。同时新型脱硫系统不设置喷头装置,通过“飓风旋流器”让烟气切割脱硫剂形成乳化层达到增加反应时间和反应面积的效果。通过某14 MW工业热水锅炉应用结果表明:高、中、低3种负荷下,新型脱硫系统均运行稳定,平均入口烟气温度为100℃,较改造前锅炉排烟温度降低30~50℃,有效提升了锅炉热效率;中负荷运行条件下,经新型脱硫系统脱硫后SO_(2)含量为10.9 mg/m^(3),脱硫效率91.2%,同时脱硫系统协同除尘效率达98.94%,再经湿式静电除尘(雾)器深度除尘后烟尘浓度为4.8 mg/m^(3),达到超低排放标准。该系统解决了传统石灰石湿法脱硫喷头装置易堵塞问题,同时省却了传统布袋除尘器,运营成本低,具有良好的推广前景。

In view of the problems of easy blockage and high operating costs of limestone-gypsum wet flue-gas desulfurization systems,a new type of integrated bubbling(emulsifying)wet desulfurization and dust removal system for fly ash recycling of coal-fired industrial boiler was developed.The traditional fly ash desulfurization is only used as a desulfurizer carrier and directly sprayed into the flue.By purifying the Ca^(2+) in the fly ash to prepare an alkaline slurry,wet desulfurization of fly ash can be achieved without adding other desulfurizers.At the same time,the new desulfurization system does not set nozzle device,and the"hurricane cyclone"allows the flue gas to cut the desulfurizer to form an emulsifying layer,so as to increase the reaction time and reaction area of the effect.The application results of a 14 MW industrial hot water boiler show that the new desulfurization system runs stably under high,medium and low loads,and the average inlet flue gas temperature is 100℃,which is 30-50℃lower than the boiler exhaust temperature before the renovation,which effectively improves the thermal efficiency of the boiler.Under medium-load operating conditions,the content of SO_(2) after desulfurization by the new desulfurization system is 10.9 mg/m^(3),and the desulfurization efficiency is 91.2%.At the same time,the synergistic dust removal efficiency of the desulfurization system is 98.94%.After deep dust removal by wet electrostatic precipitator,the smoke concentration is 4.8 mg/m^(3),which can meet ultra-low emission standards.The system fundamentally solves the traditional limestone wet desulfurization nozzle device easy blockage problem,and saves the traditional cloth bag dust collector,has low operating cost,and a good promotion prospect.