Make sure the pump is off. Then passively recover all the working solvent back into your recovery tank. In order to passively recover, open the vapor recovery port on your recovery tank. Cover your recovery tank in ice and add some salt – make sure to cover as much surface area as possible. The purpose of this step is to chill the recovery tank as much as possible which maintains a lower pressure. Read the gauge on the collection base and compare it to the recovery gauge, the collection gauge should have a higher pressure than the recovery gauge (more than 15PSI). This differential pressure will suck the butane gas back into the recovery tank slowly recovering it. Open the valve on the recovery tank to start passively recovering. The process takes a long time, (often more than 12 hours). The colder you keep the recovery tank, the faster it will recover. Dry ice or adding salt to your ice will both speed up the process by reducing the vapor pressure in the recovery tank.
Posted in: Extraction System Operation