Strategies to Mitigate Complications Associated with Unconventional Crudes in the Wastewater Treatment Plant

摘要

The oil sands hydrocarbons (OSH) in Canada and the shale plays or light, tight oils (LTO) in the USA combine to give North America the third largest oil reserve in the world after Saudi Arabia and Venezuela (US Energy Information Administration, EIA). The majority of the reserves are unconventional and therefore harder to extract and process than conventional oil. Because of the extensive extraction processes required, contaminants that challenge refinery operation are inherent in these crude sources. Until recently unconventional crude oil has been available at significant discounts to conventional oil and provided an economic incentive to the refiner despite the need for modifications to refinery configuration and infrastructure. The same consideration is rarely afforded to the wastewater treatment plant and the ultimate economic benefit to the refinery is dictated by the wastewater treatment plant's ability to consistently meet the requirements of the National Pollutant Discharge Elimination System (NPDES) permit. This paper reviews the observed effects of the main contaminants of the two primary unconventional oil sources in North America, the oil sands hydrocarbons in Canada and the tight oils in the United States, and the approaches used to mitigate detrimental consequences and improve refinery profitability.