Envent provided vapor control on 5 temporary frac tanks during a tank cleaning. The source tank was emptied of a slop oil mixture. The product was going to be separated by a centrifuge into water, oil, and solid components. The temporary tanks in use accepted water/oil outputs and contained a heavy oil/sludge input mixture. The main technical challenge in this project was ensuring that the passive carbon system would not be spent at a faster pace than what was expected, and possibly result in compliance violations. The amount of product being pumped into the frac tanks would vary along the vapor control and could not be predicted. In addition to trying to comply with our emission limits, we had to be sure that all the system was the most cost and time effective solution.
Once the scope was outlined, calculations were performed to infer the amount of carbon needed based on the vapor pressure of the tank mixture. After we gather all the products data, we were able to design a carbon system according to the type of product in the tanks, the number of tanks, the pumps output, etc. Envent used a system of two EVAC 2000 (2,000 lbs carbon vessels), including a flame arrestor, interconnecting hoses, and tank fittings.
SCAQMD permits are particularly complex for centrifuge operations and the compliance of centrifuge projects requires attention to detail. Envent engineers experience was valuable when laying out the equipment in the most efficient way so that in case of an equipment failure we would still comply with all the SCAQMD permit limits.