Paper No. 6
Presentation Time: 4:30 PM
ADDRESSING DIVERSE WATER MANAGEMENT CHALLENGES DURING HYDRAULIC FRACTURING OF SHALE FOR NATURAL GAS PRODUCTION
GREGORY, Kelvin B.1, VIDIC, Radisav
2 and DZOMBAK, David A.
1, (1)Civil & Environmental Engineering, Carnegie Mellon University, 119 Porter Hall, Pittsburgh, PA 15213, (2)Department of Civil and Environmental Engineering, University of Pittsburgh, 949 Benedum Hall, Pittsburgh, PA 15261, kelvin@cmu.edu
New drilling and well-stimulation technology has enabled a boom in natural gas exploration and production from deep, black shale formations. Shale gas is projected to be the largest contributor to growth in natural gas production in the United States for 25 years. The same is true for many other nations as recent assessments revealed substantial and technically recoverable shale gas in India, China, and Argentina among others. The technical challenges of drilling and well stimulation in deep shale are largely behind the industry. However, where shale gas resources are currently produced, water management emerged as a critical challenge for the sustainable development of these reservoirs, where hydraulic fracturing must be used. Following hydraulic fracturing, water containing high concentrations of total dissolved solids (TDS) return to the surface. The TDS concentrations in this wastewater also known as “flowback” can far exceed that of sea water and also contain hydrocarbons that add complexity and cost to the already challenging management of flowback.
Sustainable production of shale gas requires management of flowback that ensures protection of water resources. Where the infrastructure exists, deep-well injection will be the primary means of disposal. However, in many areas where shale gas production will be abundant, deep-well injection sites are not available or may not be economically feasible due to transportation costs. Moreover, the water stress associated with fresh water resources is regionally, locally, and seasonally variable. The fresh water demands for hydraulic fracturing may compete with other industrial and municipal needs and especially where the resource is limited. With water management challenges that are spatially and temporally variable and dynamic, there is no clear panacea for sustainable shale gas development. However, as hydraulic fracture moves into new shale formations with unique resource development challenges, novel technology and management solutions are emerging that enable environmentally sustainable and economically feasible natural gas extraction from shales.
