I am using the vacuum pump from KNF Neuberger Inc to create a reduced pressure environment for the dryer. I want to calculate the energy consumption of this pump. The pump is removing nitrogen gas from the dryer continuously. The pressure of the system is 500 mbar with a known flow rate (0.6L/min) and temperature (35.31 degree celcius) of nitrogen gas. I know that in order to calculate the energy consumption, I have to include the energy used to remove the nitrogen and the residual solvent. I calculated the energy used to remove the residual by multiplying the enthalphy of vapourization of the solvent with its number of mole of solvent removed. However, I get stuck with calculating the energy consumption to remove the nitrogen gas. Most of the resources are about how to find energy consumption of liquid ring pump and rotary pumps. When I used these resources as a reference, I obtained a very small value for the energy consumed. I don't think that is right.

  • $\begingroup$ can you measure the current flowing through the pump motor? $\endgroup$ – niels nielsen Apr 13 '19 at 17:42
  • $\begingroup$ No, I don't think the current is needed to calculate the energy consumption. It depends on the properties of the gas removed by the pump $\endgroup$ – Tammy Chong Apr 13 '19 at 18:49
  • $\begingroup$ If you know the energy consumption of the pump motor, you can set an upper bound on the energy required to evacuate the chamber. In fact, the dollar cost of a pumpdown is the electricity cost of running the pump. $\endgroup$ – niels nielsen Apr 13 '19 at 19:39

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.