The jet pump is suitable for high temperature, high pressure and high vacuum fields, such as vacuum evaporation, vacuum drying, vacuum refrigeration, vacuum distillation, lifting liquid, alkali or abrasive containing suspension, and also suitable for special environment of strong radiation.
The steam jet pump is a jet vacuum pump that uses water vapor as a working medium and can directly vent the atmosphere. The pump is quick to start, has a small footprint, a wide working pressure range, and a large amount of pumping, which can remove dust, corrosive and flammable and explosive gases. It is economical to use surplus or discarded steam. The disadvantage of this kind of pump is that the civil construction investment is high (the installation height needs more than 10m) and the cooling water consumption is large. The compression ratio of a single-stage steam jet pump is generally not more than 10.
Air jet pumps use compressed air or atmospheric air as the working medium. A low pressure is generated by the air flow at the nozzle outlet to draw air or other gas, which is then compressed and discharged. According to whether the working medium is high pressure air or normal pressure air, it is divided into general air jet pump and atmospheric jet pump. The air jet pump has a large working medium and must have a large capacity air compressor. Most air jet pumps are single staged.
When the required degree of vacuum is not too high, a certain pressure of water can be used as a water jet pump for the working fluid to generate a vacuum. The speed of water jet is often around 15-30 m/s. It is a rough vacuum device. Since the water jet pump has the dual function of generating vacuum and condensing steam, it is extremely widely used.