Vacuum pump cooler

Vacuum pump is a kind of equipment that uses physical or chemical methods to extract the vacuum from the container. With the development of enterprise production and scientific research, the requirements of process specification and pressure range of vacuum technology are more and more strict, especially the rapid growth of the downstream application industry of vacuum pump and the continuous expansion of application field promote the rapid development of vacuum pump industry.

The commonly used vacuum pumps are dry screw pump, water ring vacuum pump, reciprocating vacuum pump, slide valve vacuum pump, roots vacuum pump and diffusion pump. The specifications of vacuum pump are different according to the specific application in different industries. There are large turbine vacuum pumps suitable for petrochemical industry and miniature vacuum pumps for high precision in laboratory.

A variety of vacuum pump equipment also restricts the performance and quality of its supporting equipment. Vacuum pump water chiller is a key supporting equipment. Water ring vacuum pump, roots vacuum pump, diffusion pump and other types need water chiller as a supporting device to stabilize equipment temperature and improve vacuum efficiency.

Let’s look at a practical application of vacuum pump cooling

In order to meet the development needs of a plastic enterprise, the workshop needs to provide a special chiller for the high-power vacuum pump to stabilize the internal working fluid temperature of the vacuum pump equipment and realize high vacuum and high-efficiency production.

Vacuum pump special refrigeration equipment, with excellent refrigeration performance, economic performance has been recognized by customers, and finally determined the model of water-cooled box chiller.

Technical difficulties and principle analysis of the project:

Take the water ring vacuum pump as an example, the water temperature of the water ring will rise under the impelling of the impeller, while the vacuum degree of the suction chamber of the vacuum pump is high, the pressure is low, and the corresponding saturated steam temperature is also low. When the water temperature rises to this temperature, it will be vaporized, resulting in the decrease of vacuum suction capacity and the working efficiency of the vacuum pump.

The ability of water ring vacuum pump to reduce steam depends on coolant temperature and flow rate.

Assuming that the limit suction pressure of the vacuum pump is 4.2kpa, the corresponding saturation temperature is about 30 degrees. If the water temperature rises by 4 degrees during the operation of the vacuum pump, the temperature of the working fluid of the vacuum pump should be below 26 degrees to ensure the performance of the vacuum pump.

Therefore, the cooling temperature range and water flow rate are the key points in the selection of water chillers. After contacting the project, we communicated with the technical personnel of both sides of the customer to confirm the cooling demand of vacuum equipment.

Working water of vacuum pump: the water temperature at the outlet of vacuum pump is 42-50 ℃, which needs to be reduced to 15-22 ℃;

The flow rate of chilled water is 18 cubic meters per hour and the pressure is 0.1 MPa. The cooling water supplied in summer is 36-41 degrees.

According to the demand, the water-cooled box type water chiller is customized, which consists of three 25p units in series, with a total of 6 turbine compressors, shell and tube evaporators in series and shell and tube condenser in series, and the heat exchange area of the evaporator is increased; the refrigerating capacity is 201756 kcal, and the chilled water working condition is: chilled water inlet temperature is 12 ℃, outlet temperature is 7 ℃, cooling water inlet temperature is 30 ℃, and outlet temperature is 35 ℃.

The temperature control of vacuum pump working fluid is one of the main reasons for the decline of vacuum equipment performance and low vacuum. Therefore, the special vacuum pump water chiller should be equipped for the temperature control of vacuum pump, and regular routine maintenance should be carried out after the cooler is put into use;

In order to reduce the energy consumption of large-scale vacuum pump, it is necessary to innovate the operation mode of large-scale vacuum pump and reduce the energy consumption.

With the progress of industrial technology, vacuum equipment is widely used in vacuum evaporation, vacuum concentration, crystallization, distillation, sublimation, drying, dehydration and other technological processes, and temperature control is one of the important parameters of all processes.