Sustainable Management of Flowback Water during Hydraulic Fracturing of Marcellus Shale for Natural Gas Production

Abstract

This study evaluated the feasibility of using abandoned mine drainage (AMD) as makeup water for the reuse of produced water for hydraulic fracturing. There is an abundance of AMD sources near permitted gas wells as documented in this study that can not only serve as makeup water and reduce the demand on high quality water resources but can also as a source of chemicals to treat produced water prior to reuse. The assessment of AMD availability for this purpose based on proximity and relevant regulations was accompanied by bench-and pilot-scale studies to determine optimal treatment to achieve desired water quality for use in hydraulic fracturing. Sulfate ions that are often present in AMD at elevated levels will react with Ba 2+ and Sr 2+ in produced water to form insoluble sulfate compounds. Both membrane microfiltration and gravity separation were evaluated for the removal of solids formed as a result of mixing these two impaired waters. Laboratory studies revealed that neither AMD nor barite formed in solution had significant impact on membrane filtration but that some produced waters contained submicron particles that can cause severe fouling of microfiltration membrane. Coagulation/flocculation was found to be an effective process for the removal of suspended solids and both bench-and pilot-scale studies revealed that optimal process conditions can consistently achieve the turbidity of the finished water below 5 NTU. Adjusting the blending ratio of AMD and produced water can achieve the desired effluent sulfate concentration that can be accurately predicted by chemical thermodynamics. Co-treatment of produced water and AMD will result in elevated levels of naturally occurring radioactive materials (NORM) in the solid waste generated in this process due to radium co-precipitation with barium sulfate. Laboratory studies revealed that the mobility of barite that may form in the subsurface due to the presence of sulfate in the fracturing fluid can be controlled by the addition of appropriate antiscalants.

Accumulation of Marcellus Formation Oil and Gas Wastewater Metals in Freshwater Mussel Shells

“…This technology has allowed a shift in electricity generation away from coal to cleaner-burning natural gas, which may prove an important intermediate in the search for clean energy independence. , Despite the benefits, concerns have been raised about the potential negative impact of HVHF on water quality. − In the Marcellus Shale Formation, the third largest shale play in the U.S., the median well requires 27.9 million liters (ML) of water injected for natural gas extraction. Approximately 4 ML of the injected water returns to the surface with high concentrations of total dissolved solids (TDS > 100 000 mg/L), metals, and radioactivity. ,,− Since 2011, in Pennsylvania, the state with the largest oil and gas production from the Marcellus, between 70% and 90% of wastewater fluid that returns to the surface is reused in subsequent drilling and HVHF operations. , However, between 2008 and 2011, over 2.9 billion liters of oil and gas (O&G) wastewater was discharged to waterways following treatment at centralized waste treatment facilities under National Pollutant Discharge Elimination System (NPDES) permits ,,, (Supporting Information Figure S1).…”

“…2,5,8−14 Since 2011, in Pennsylvania, the state with the largest oil and gas production from the Marcellus, between 70% and 90% of wastewater fluid that returns to the surface is reused in subsequent drilling and HVHF operations. 15,16 However, between 2008 and 2011, over 2.9 billion liters of oil and gas (O&G) wastewater was discharged to waterways following treatment at centralized waste treatment facilities under National Pollutant Discharge Elimination System (NPDES) permits 4,7,15,16 (Supporting Information Figure S1).…”

Unconventional Hydrocarbon Resources: Prospects and Problems

“…Relatos apontam que o processo de extração estaria causando a impregnação de metano nas águas subterrâneas em campos de exploração de KHARAK et al, 2013;VIDIC, 2015;BLUMSACK, 2014).…”