View Full Version : Control over energy usage

28-03-2011, 08:08 PM
Hello new here, i work in a large production facility. We have installed the Hench system wich allows us to have some control over energy usage. Has anyone had any experience with these systems , recomendations , this is a basic outline of our plant
2 stage- 3 boosters 2psig suction aqnd 5 high stage running 28 psig suction and 140 discharge. the condensers control was very tight now we are getting a 40psi swing 143 down to 107. in my opinion this is causing oil carryover and low operating temperatures through the compressors. we have mycom 500 hp comp. what is the best way to get rid of the large swing on discharge pressures? any help will be greatly appreciated, Mike

04-04-2011, 07:46 PM
Normally to save energy, you want to let the head pressure float down as low as practical. There are a coiple of limiting factors on how low you can drop the head pressure.

At lower head pressures, you wil want to check your oil separtor design for the lower pressures, as you will have a higher velocity in the separator. The Coalescer elements should not be over loaded based on velocity. Overloading can cause oil carry over. Also, if you let the head pressure drop too fast, you can get some oil foaming which leads to oil carry over.

Nex issue is having enough differental pressure to push the high pressure liquid to the next lower pressure and maintain suffucient flow. If the machine has liquid injection oil cooling, you need to keep the head up enough that the liquid injection will feed.

Hench should have at least check your oil separator design and lowest pressure acceptable for plant operation.

AS fo keeping the discharge pressur up, you can go into the Hench system and set the fan cycling parameters on the condenser. The IOM or help screen should tell you how to get to that function.


05-04-2011, 07:19 PM
Thank you for the help i will do some more research, Mike