基于过热蒸汽动能磨的粉煤灰超细粉碎技术

Fly Ash Ultrafine Grinding Technology based on Superheated Steam Powered Mill

蒸汽动能磨是利用Laval喷嘴产生超音速气流加速粉碎腔中的物料,使物料在相互碰撞、摩擦中粉碎的技术,利用该技术进行粉煤灰的超细粉碎加工可高效、经济地制备各种微米尺度的粉煤灰超微粉体。在分析研究基于蒸汽动能磨的粉煤灰超细粉碎加工技术与现有粉煤灰粉碎技术优缺点的基础上,创造性地提出基于剪切粉碎的磨内三段式气体运动理论的过热蒸汽动能磨技术,基于该技术建成年产3万t的过热蒸汽动能磨中试试验装置,并连续稳定运行8个月。结果表明:生产粒径D97=15µm的高细粉煤灰时,其产量达到3.4 t/h;生产粒径D97=10µm的高细粉煤灰,产量达到1.8 t/h。该中试装置的运行数据为基于过热蒸汽动能磨的粉煤灰超微粉碎工业生产线的大规模应用提供了数据基础。

The steam powered mill is a kind of technology that uses Laval nozzle to produce supersonic steam flow to accelerate the materials in grinding chamber,where materials are ground in the process of mutual collision and friction.Utilizing this technology to conduct ultrafine grinding of fly ash can efficiently and cost-effectively produce ultramicro fly ash of various micron sizes.On the basis of analyzing and studying the advantages and disadvantages of fly ash ultrafine grinding technology based on steam powered mill compared with current fly ash grinding technology,this paper creatively proposes the superheated steam powered mill technology on the basis of the shear grinding-based three-stage kinetic theory of gases in mill.A superheated steam powered mill pilot test plant with annualproduction capacity of 30,000t utilizing this technology is built and runs stably for consecutive 8 months.The results show that the production capacity reaches up to 3.4t/h when highly fine fly ash with particle size D97=15um is produced,and reaches 1.8t/h when highly fine fly ash with particle sizeD97=10um is produced.The operation data of such pilot test plant provides data basis for the wide application of fly ash ultramicro grinding line utilizing superheated steam powered mills.