工业炉窑高温含尘烟气金属丝网除尘技术研究

Research on metalwirework filter dust removal technology for high temperaturedusty flue gas of industrial furnace

工业炉窑生产中产生的大量高温含尘气体携带了大量的余热余能,若能得到合理回收利用,将创造巨大的经济价值和环保价值,因此,对高温气体净化除尘是一项实现资源合理利用和环境保护的关键技术。新型的金属多孔材料凭借良好的耐温性、机械性能和导热性等,在高温烟气除尘方面具有很好的适用性和优越性。选择金属丝网除尘器作为研究对象,通过试验和数值模拟相结合的方法,探究除尘器进口气流流量、气流含尘浓度、气流入口温度对于除尘系统压降的影响规律。结果表明,系统压降随着进口空气流量的增大而升高,当进气流量从0.4 Nm 3/h增加到34.3 Nm 3/h时,压降从12.6 Pa迅速升高到1989 Pa,通入含尘气体产生的系统压降要高于通入相同流量的洁净空气产生的系统压降,压降随着含尘浓度的增加有上升趋势,但含尘浓度大于53 g/m 3时,压降反而下降。进气温度越高,系统平均压降越高,进气温度从13℃上升到202℃时,压降从520.5 Pa上升到941.5 Pa。系统压降与出口温度的模拟结果与试验结果吻合较好。对于进气温度较低(<300℃)的工况条件,除尘器的系统压降主要来自于金属丝网滤袋的表面压降;当温度上升后,压降上升很快,当温度为600℃时,系统压降在3000 Pa左右,远高于滤袋表面压降,这时需要考虑除尘器结构压降带来的影响。

The large number of high-temperature dust-containing gases produced in the production of industrial furnaces carry a lot of waste heat and energy.If they can be reasonably recycled,it will create great economic and environmental value.Therefore,the purification and dust removal of high-temperature gas is a key technology to realize the effective utilization of resources and environmental protection.The new metal porous material has excellent applicability and superiority in high-temperature flue gas dust removal due to its good temperature resis tan ce,mechanical properties,and thermal conductivity.In this paper,the metal wirework ash bag filter was selected as the research object.Through the combination of experiment and numerical simulation,the influences of the inlet air flow rate,dust concentration,and inlet temperature on the pressure drop of the dust removal system were explored.The experimental results show that the pressure drop of the system increases with the increase of the inlet air flow rate.When the inlet clean air flow rate increases from 0.4 Nm 3/h to 34.3 Nm 3/h,the pressure drop increases rapidly from 12.6 Pa to 1989 Pa.The system pressure drop of dusty gas is higher than that of clean air under the same gas flow rate and the pressure drop increases with the increase of ash concentration in gas.When the dust concentration is higher than 53 g/m 3,the pressure drop decreases.The higher the inlet temperature is,the higher the average pressure drop of the system is.When the inlet temperature rises from 13℃to 202℃,the pressure rises from 520.5 Pa to 941.5 Pa.The simulated pressure drops and outlet temperatures are in good agreement with the experimental results.Under the conditions of lower inlet temperatures(<300℃),the system pressure drop of dust collector is mainly affected by the surface pressure drop of the metal wirework filter bag.When the inlet temperatures increases,the pressure drop increases significantly.The pressure drop is approximately 3000 Pa for the inlet temperature of 600℃,greatly higher than thesurface pressure drop of the bag filter.And thus the pressure drop of the structure of dust collector needs to be considered during the design of bag filter.