- #1
Amused_1
- 7
- 1
Hi all. First, some context.
I work for a small seed oil extraction plant where we cold press the seed then solvent extract the residual oil from the presscake. In the solvent extraction plant we use liquid ring pumps to pull the required vacuums. The Plant Vac Pump (PVP) is used in all operations and pulls the vacuum for the 1st effect, 2nd effect, the Oil Stripping Column (OSC) and the Mineral Oil System (MOS, also known as the Solvent Air Separator). This typically pulls a vacuum of around -600 millibar when distillation is in full swing.
We also have a High Vac Pump (HPV) that pulls a vacuum on a separate vessel called the High Vac Dryer at around -850 millibar, but this is used only when the finished oil requires a <1ppm residual solvent content.
Both pumps use water as a service liquid, which is typically around 20-30 Celsius.
Recently, when using just the PVP, we’ve noticed the top of the Vac Tank getting hot. The water doesn’t seem to increase much in temp, but the space above it (and the ceiling of the tank itself) feels like it could be around 50-60 Celsius. We’ve traced it back to the pump itself - the inlet pipe for the water is no warmer than usual, the vapour inlet that the pump is pulling on is cool as any air/vapour present has been pulled through a condenser, yet the outlet for the water is again around 50-60C.
We’ve gagged back the valve on the vapour inlet which has reduced the vacuum to between -500 and -550 and found this has reduced the temp on the outlet, but moving forward we’re not sure how to solve the issue.
Would anyone have any thoughts? I can provide more info if needed, but figure there was plenty above to chew on!
I work for a small seed oil extraction plant where we cold press the seed then solvent extract the residual oil from the presscake. In the solvent extraction plant we use liquid ring pumps to pull the required vacuums. The Plant Vac Pump (PVP) is used in all operations and pulls the vacuum for the 1st effect, 2nd effect, the Oil Stripping Column (OSC) and the Mineral Oil System (MOS, also known as the Solvent Air Separator). This typically pulls a vacuum of around -600 millibar when distillation is in full swing.
We also have a High Vac Pump (HPV) that pulls a vacuum on a separate vessel called the High Vac Dryer at around -850 millibar, but this is used only when the finished oil requires a <1ppm residual solvent content.
Both pumps use water as a service liquid, which is typically around 20-30 Celsius.
Recently, when using just the PVP, we’ve noticed the top of the Vac Tank getting hot. The water doesn’t seem to increase much in temp, but the space above it (and the ceiling of the tank itself) feels like it could be around 50-60 Celsius. We’ve traced it back to the pump itself - the inlet pipe for the water is no warmer than usual, the vapour inlet that the pump is pulling on is cool as any air/vapour present has been pulled through a condenser, yet the outlet for the water is again around 50-60C.
We’ve gagged back the valve on the vapour inlet which has reduced the vacuum to between -500 and -550 and found this has reduced the temp on the outlet, but moving forward we’re not sure how to solve the issue.
Would anyone have any thoughts? I can provide more info if needed, but figure there was plenty above to chew on!