Can a water ring pump use a high-boiling-point liquid instead of water?
Thread Content
Due to environmental regulations, our factory now uses a closed liquid ring tank for water supply. In the distillation of butyl alcohol, the presence of methylethyl ketone in the crude product causes the water in the liquid ring tank to contain large amounts of this compound. My idea is to use high-boiling-point butanol waste as a circulating medium; in this way, when the contents of methanol and ethanol in the waste are high, the separation becomes easier due to the large difference in boiling points.
If butan-1-ol has a higher boiling point than water, it should work.
Of course. With the current strong pressure to protect the environment, water used in water ring pumps must be recycled; materials inevitably end up in the water, and the water temperature rises as well. To maintain a vacuum level, heat exchangers are needed to cool the water. By using organic solvents with high boiling points as the liquid ring, it is possible to maintain the vacuum level while also separating the materials contained in the solvent, thereby reducing consumption and protecting the environment.
It should be possible. However, if the temperature in the liquid ring groove rises, the pressure inside the groove may increase; be careful for safety. We use open containers for our liquid ring tanks.
Our current liquid ring tank is completely sealed; otherwise, the gas from both the primary and secondary systems would leak out. The liquid ring tank is cooled by a coil inside it using low-temperature water. The exhaust port of the liquid ring groove is connected to the exhaust gas condenser, where the gases A and B are condensed before being discharged. These components A and B tend to aggregate together, blocking the pipes; as a result, the liquid ring tank swells and liquid spills out from the level gauge in that tank.
I strongly agree with the original poster’s opinion. Our factory has had this problem. First, a condenser and an oil-water separator were added to the liquid ring tank, but it still didn’t work. What we did was switch to slide vane pumps instead of water ring pumps; before the gas enters the pump, it is cooled in a tank at -20 degrees Celsius (this is very important – I think preprocessing before entry into the pump is more scientific than preprocessing after it enters). The gas is then liquefied and collected.
The opinion from upstairs is valid; it seems better to replace the pump after all.
Of course, pre-treatment before feeding it into the pump is better; this is done under vacuum conditions, where the boiling point of the material is very low, and a colder environment is required to turn it into a liquid. There’s also the issue that if the component pulled out contains water, it will freeze. That would require two heat exchangers in series, one using low-temperature water and the other using dual cooling.
We also have slide valve pumps in our workshop; we’ve used them before. This is to prevent things from being pulled out; it’s not a problem like with water ring pumps where things can be pulled out. Also, the gas discharged by this pump seems to smell very bad.
The liquid ring groove is usually open, right? Unorganized waste gas also presents challenges; factors such as the viscosity of the residual materials, the presence of solid impurities, and iron shavings need to be taken into consideration. Also, if a solvent is used instead of water, will the pump head of the water ring pump corrode and age, and will it affect the vacuum level? I remember that when the concentration of solute in the water pump is too high, it has a significant impact on the vacuum level; therefore, the water needs to be changed frequently. Could the use of a liquid ring pump be considered?
Water jet pumps contain solvents, basically volatile solvents. The presence of these solvents prevents the vacuum from being achieved, as their vapor pressures are high. High-boiling organic solvents have no effect. The back portion of the residue is a bit viscous, but it can flow; it’s quite fresh and free of any solid impurities. I came up with this plan to better address the issue of pollution. The water pump should also be able to use such solvents as a substitute; when a large amount of organic matter is extracted, it can be burned as fuel as well. This is better than using water as a medium, as it makes the processing easier. It’s not the case that when the organic solvent is extracted, it will separate into layers in water and can be easily separated; in fact, when the amount of organic material extracted is very small, no separation into layers occurs – instead, it volatilizes into the air. Our liquid ring tank is emptied after condensation by the condenser.