Steam
jet pump
Water vapor jet pump is a jet vacuum pump which takes water vapor as the working medium and can directly exhaust the atmosphere. The pump has the advantages of fast starting, small floor area, wide working pressure range and large air extraction, and can extract dust, corrosive, flammable and explosive gases. It is more economical to use surplus or waste steam. The disadvantages of this pump are high civil engineering investment (installation height of some requires more than 10m) and large cooling water consumption. The compression ratio of single-stage steam jet pump generally does not exceed 10.
Air
jet pump
The air jet pump uses compressed air or atmospheric air as the working medium. The air flow generates low pressure at the nozzle outlet to suck air or other gases, and then compresses it out. According to whether the working medium is high-pressure air or atmospheric air, it is divided into general air jet pump and atmospheric jet pump. The working medium consumption of air jet pump is large, so it must have an air compressor with large capacity. Generally, most air jet pumps are single-stage.
Water
jet pump
When the required vacuum degree is not too high, a water jet pump with a certain pressure of water as the working fluid can be used to generate vacuum. The water jet speed is usually about 15-30m / s. It belongs to crude vacuum equipment. Because the water jet pump has the dual function of generating vacuum and condensing steam, it is widely used.