In a golden age of corporate personhood, U.S. refineries may actually have more in common with humans than ever before. Water sustains both human and refinery life. As a community’s water consumption increases, so must its municipal wastewater treatment capacity increase. Likewise, as regulations necessitate more hydrotreatment processing, refineries must increase sour water treatment capacity. While this notion might harmoniously unify a refinery and its perpetually protesting community, in reality it causes downstream issues with contamination risks galore.
As a general rule in wastewater treatment, “do not mix different wastewater streams before treatment.” Although cooling water and sanitary sewage may require the least amount of treatment, an operator must be mindful of the refinery’s process and instrument drawing (P&ID) in the event of an oil spill, in which these flows could be contaminated. Storm water may be contaminated by air pollutants and should be dealt with accordingly. The most heavily polluted wastewater feeds stream from process water and steam units; these must be sweetened, and oils and solids must be separated from the wastewater.
In order to minimize the load on the treatment units, the operator must separate different wastewater streams based on their characteristics. A complete wastewater characterization includes biochemical oxygen demand (Standard Methods 5210), chemical oxygen demand (Standard Methods 5220), suspended solids, hydrocarbon content, nitrogen content, phenols [all in mg/L], and acidity [pH]. The EPA provides guidelines for industrial wastewater limitations and Standard Methods for the Examination of Water and Wastewater provides EPA-approved wastewater analytical procedures.
In July 2012, The Carlyle Group and Sunoco, Inc. formed a joint venture, Philadelphia Energy Solutions, to continue refinery operations at the oldest continuously operating refinery on the east coast. The Carlyle Group and the Commonwealth of Pennsylvania agreed to provide funding for the catalytic cracker unit, a train terminal for transporting Bakken crude oil, and a mild hydrocracker unit. All of these modifications will increase the water consumption as well as the required wastewater treatment capacity of the refinery. The EPA required Sunoco to continue to remove groundwater contaminants such as hydrocarbons and heavy metals. On the other hand, the new owners must increase their wastewater treatment capacity. While there are plenty of people who might disagree, I believe this has been the healthiest business agreement in past decade between industry and government in the PA energy sector.