1. What is the role of the vacuum pump? What kinds of vacuum pumps are commonly used in refineries? The vacuum pump is designed to create a vacuum in the equipment or container that operates below ambient atmospheric pressure or high vacuum. Vacuum pumps commonly used in refineries include steam jet vacuum pumps, water ring vacuum pumps and reciprocating vacuum pumps.

2. What is the working principle of the steam jet vacuum pump? It consists of a nozzle, a mixing chamber, an expansion chamber, and a pressure outlet. In operation, water vapor is sprayed from the nozzle into the mixing chamber at a high speed (1200-1500 m/s). At this time, a certain negative pressure is generated at the nozzle, so that the pumped gas is flushed into the mixing chamber from the gas inlet and mixed with water vapor. And get some energy from the water vapor. When the mixed gas stream enters the diffuser chamber, the velocity gradually decreases along the axis, and the pressure gradually increases along the axis flow until it is discharged above the atmospheric pressure. Due to the continuous work, the gas in the equipment is continuously extracted, thus causing a vacuum (negative pressure) state inside the equipment.

3. What are the characteristics of the steam jet vacuum pump? The steam jet vacuum pump entrains the pumped gas at a high speed of water vapor, so it has the characteristics of large pumping capacity, high vacuum, simple manufacture, convenient installation and maintenance, etc. Currently, the vacuum distillation unit of the refinery Most of the vacuum pumps used are steam jet vacuum pumps.

4. What is the construction of the water ring vacuum pump? What is the working principle of the water ring vacuum pump? The water ring vacuum pump is composed of a pump casing, an impeller, a water ring, a suction chamber, a discharge chamber, and a vent hole.