Efficient combined type vacuum oil-gas separation method

The invention belongs to the technical field of vacuum oil filtration, and particularly relates to an efficient combined type vacuum oil-gas separation method, which is characterized in that on the basis of an existing vacuum tank, a natural air cooling type rotary vane vacuum pump and a roots booster pump are simultaneously mounted; the natural air-cooled rotary vane vacuum pump is a first-stage vacuum pump, and the roots booster pump is a second-stage vacuum pump; firstly, the first-stage vacuum pump is started to pump the atmospheric pressure in the vacuum tank to 4500 pa, and then the second-stage vacuum pump is started to pump the atmospheric pressure in the vacuum tank to a set value. The vacuum pumping efficiency is improved, the oil-gas separation time is shortened, and the oil quality is improved. 本发明属于真空滤油技术领域，具体为高效复合式真空油气分离方法，在现有真空罐的基础上，同时各安装一个自然风冷式旋片真空泵和罗茨增压泵；所述自然风冷式旋片真空泵为一级真空泵，所述罗茨增压泵为二级真空泵；首先启动一级真空泵将真空罐内的大气压抽至4500pa后再启动二级真空泵将的真空罐内的大气压抽至设定值。本发明提高了抽真空效率、缩短了油气分离时间和提高了油品质量。