Exhaust purification for oil-free vertical vacuum pumps
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Our company currently uses a large number of WLW series oil-free vertical vacuum pumps, which perform well. However, with the increasing strictness of environmental regulations, the exhaust gas from oil pumps also needs to be routed through waste gas treatment systems. In actual operation, it was found that the concentration of organic substances in the exhaust gas is high, which can easily lead to excess levels of waste gas. We installed a 4-square-inch tube-type condenser at the exhaust outlet, cooled by ice brine, but when using vacuum, the exhaust concentration was still very high; a handheld PGM7320 detector showed a concentration as high as 15,000 mg/m3, which far exceeds the processing capacity of the waste gas treatment facilities. At present, our exhaust pipelines and vacuum pump exhausts are connected in a fixed manner; the exhaust gas is under negative pressure, while the vacuum pump is used for exhaust. I hope the experts can give some advice on how to handle this?
The so-called oil-free vertical reciprocating pumps are merely a term used in comparison to earlier types of reciprocating pumps; in reality, they still contain a very high amount of oil. This high oil content greatly complicates the recovery of the substances present in the exhaust gases, and since these substances contain oil, recovery becomes almost meaningless. In terms of exhaust gas recovery technology, a combination of gas washing, condensation, and adsorption is typically used; relying solely on condensation yields very limited results, as the concentration level depends mainly on the physicochemical properties of the condensable substances.
We are facing the same problem at the moment, as the exhaust gas from vacuum pumps contains complex components. Depending on the plastic products we produce, the composition of this exhaust gas varies; it mainly includes acrylonitrile, small plastic molecules, styrene, water vapor, and other benzene derivatives. Handling this waste is extremely difficult, as it cannot be effectively removed using single treatment methods. I also hope that the experts in this group will not hesitate to share their knowledge and make significant contributions to environmental protection.