Positive displacement blower, Cement Industry, Mining industry L Roots type blowers/vacuum pump is designed by National Union Associated ... /minVacuum Degree: -9.8~-39.2 kPa;Application:Widely used in Power, Petroleum Chemical, Fertilizer, Steel, Metallurgy, Oxygen Producing, Cement, ... Abatement, Aquaculture, Sewage Treatment, Pneumatic Conveying and etc. diverse industries. Roots Blower for Cement