透气膜用重质碳酸钙粉体粉磨分级工艺研究

On Grinding and Grading Technology of Heavy Calcium Carbonate Powder for Breathable Film

结合透气膜专用重质碳酸钙粉体的d_(97)细度和2μm细粉含量等应用指标及其产业化关键技术,从粉磨、分级和流场稳定技术角度,探讨了与粉磨分级稳流有关的磨盘转速、磨辊压力、入料粒度、料层厚度、分级转速和风量风压流场等工艺参数,实验结果证明,在磨盘转速为42 rpm,入磨颗粒尺寸标准为≤8 mm,料层厚度为6 cm,磨辊粉磨压力为60 k Pa;分级机分级转速为1400 r/min,风压为12.1k Pa,风量为27×10^(3)m^(3)/h等工艺参数集成下,其成品细度d_(97)=16.03~17.52μm,2μm细粉含量28.9%~30.3%,达到透气膜专用重质碳酸钙粉体产品的d_(97)细度及其2μm细粉要求。

This paper combines the application indicators of special heavy calcium carbonate powder for permeable membrane,such as d_(97)fineness and 2μm fine powder content,and the key technologies for its industrialization,and discusses the process parameters related to grinding,classification,and flow stabilization from the perspective of grinding disc speed,roller pressure,feed size,bed thickness,classification speed,and air volume and pressure flow field.The experimental results show that when the grinding disc speed is 42 rpm,the feed particle size standard is≤8 mm,the bed thickness is 6 cm,and the roller grinding pressure is 60 kPa;the classification machine classification speed is 1400 rPm,the air pressure is 12.1 kpa,and the air volume is 27×10^(3)m^(3)/h,etc.,the finished product fineness d_(97)=16.03~17.52μm,2μm fine powder content 28.9%~30.3%,which meets the d_(97)fineness and 2μm fine powder requirements for special heavy calcium carbonate powder for permeable membrane.