Midwest Petroleum Refinery for Benzene Contaminated Tank Vent
Waste oil containing several 100 ppm of benzene was being stored at a midwest petroleum refinery. For environmental compliance, the vent from this tank was being sent to a thermal oxidizer.
In March, the thermal oxidizer failed sending the benzene-laden vent gas into the atmosphere. An emergency scrubber was installed, which was able to reduce the benzene using water.
Because benzene is not very water soluble, there was a large overflow volume from the scrubber, close to 400 gpm. This created an overload situation for the plant’s wastewater treatment plant. There was also a slight benzene odor coming from the scrubber exhaust.
The petroleum refinery contacted OMI Industries to learn how Ecosorb® products have been used in scrubbers to enhance gas odor removal. OMI Industries commissioned a test to prove the effectiveness of Ecosorb 206 on benzene.
Results showed that with the use of a 25:1 dilution, Ecosorb 206 in water, the solubility of the benzene was increased by 264 times.
Increased solubility results in less gas in the air, leading to a reduction in odor.
The increase in solubility of the benzene, via a small amount of Ecosorb 206, was used by the plant in the scrubber. Ecosorb 206 had an immediate effect on eliminating the benzene odor coming from the scrubber and reducing the scrubber overflow going to the wastewater treatment plant. (Water overflow went from 400 gpm to about 4 gpm.)
This reduced the overload problem at the waste treatment plant. The plant maintained its environmental compliance in both the air and water. A new thermal oxidizer was commissioned and operational in about 8 months after the initial unit failure.