SPE Paper Analyzes Challenges of Reusing Produced Water Source: SPE
Produced water is an inextricable part of the hydrocarbon recovery processes, yet it is by far the largest volume waste stream associated with hydrocarbon recovery. Water production estimates are in the order of 250 million B/D in 2007, for a water-to-oil ratio of approximately 3:1, and are expected to increase to more than 300 million B/D between 2010 and 2012.
Increasingly stringent environmental regulations require extensive treatment of produced water from oil and gas productions before discharge; hence, the treatment and disposal of such volumes costs the industry annually more than USD 40 billion. Consequently, for oil and gas production wells located in water-scarce regions, limited freshwater resources in conjunction with the high treatment cost for produced water discharge makes beneficial reuse of produced water an attractive opportunity.
Water consumption worldwide is roughly split, with 70% agricultural use, 22% industrial use, and 8% domestic use. A fifth of the population lives in areas of water scarcity, and one in eight lacks access to clean water. Currently, properly treated produced water can be recycled and used for waterflooding [produced water re-injection (PWRI)] and other applications, such as crop irrigation, wildlife and livestock consumption, aquaculture and hydroponic vegetable culture, industrial processes, dust control, vehicle and equipment washing, power generation, and fire control. These beneficial reuses directly decrease the withdrawal of potable water, a highly valuable commodity in many regions of the world. Although produced water can potentially be treated to drinking water quality, little research has been done on the feasibility and cost-effectiveness of direct or indirect potable reuse of produced water from oil and gas production.
Read the full paper here (PDF).