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Liang J, Zhang L, Li C, Mo Z, Ye M, Zhu Z, Sun S, Wong JWC. Triclocarban transformation and removal in sludge conditioning using chalcopyrite-triggered percarbonate treatment. JOURNAL OF HAZARDOUS MATERIALS 2024; 463:132944. [PMID: 37951173 DOI: 10.1016/j.jhazmat.2023.132944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 10/26/2023] [Accepted: 11/04/2023] [Indexed: 11/13/2023]
Abstract
Herein, a facile combination approach of chalcopyrite and sodium percarbonate (CuFeS2+ SPC) was established to augment both TCC removal efficiency and sludge dewatering. Results showed that utilizing the CuFeS2 dosage of 600 mg/g total solids (TS) under the optimal condition, along with the SPC dosage of 12.5 mg/g TS, an initial pH of 4.0, and a reaction duration of 40 min, led to a substantial reduction of 53.9% in the TCC content within the sludge, accompanied by a notable decrease of 36.9% in the water content. Compared to well-studied iron-based advanced oxidation processes, CuFeS2 + SPC treatment proved to be more cost-effective and environmentally friendly. Mechanistic findings demonstrated that •OH oxidation played a significant role in TCC removal, with O2•- and 1O2 acting as secondary factors. During the CuFeS2 + SPC process, the received •OH, O2•-, and 1O2 destroyed the main binding sites of extracellular polymeric substances to TCC, including tryptophan-like protein, amide, CO stretch, and -COO- functional groups. As a result, approximately 50% of TCC was partially degraded within the solid sludge phase after the attack of radicals. Meanwhile, the decreased macromolecular organic compounds in solid sludge attenuated the binding efficacy of TCC, giving rise to the transfer of partial TCC to the liquid phase. Ultimately, the TCC in sludge was successfully removed, and five transformation products were identified. This study significantly contributes to our understanding regarding TCC transformation and removal in the sludge conditioning process.
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Affiliation(s)
- Jialin Liang
- Engineering and Technology Research Center for Agricultural Land Pollution Integrated Prevention and Control of Guangdong Higher Education Institute, College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China.
| | - Lei Zhang
- Engineering and Technology Research Center for Agricultural Land Pollution Integrated Prevention and Control of Guangdong Higher Education Institute, College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Chengjian Li
- Engineering and Technology Research Center for Agricultural Land Pollution Integrated Prevention and Control of Guangdong Higher Education Institute, College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Zhihua Mo
- Engineering and Technology Research Center for Agricultural Land Pollution Integrated Prevention and Control of Guangdong Higher Education Institute, College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China; School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
| | - Maoyou Ye
- Engineering and Technology Research Center for Agricultural Land Pollution Integrated Prevention and Control of Guangdong Higher Education Institute, College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Zhi Zhu
- Institute of the Green Chemistry and Chemical Technology, Jiangsu University, Zhenjiang 212000, China
| | - Shuiyu Sun
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Jonathan W C Wong
- Institute of Bioresource and Agriculture, Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong Special Administrative Region, China
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2
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Bai H, Li Y, Lu P, Li Y, Zhang L, Zhang D, Wang X, Zhou Y. Effect of environmental factors on accumulation of trace metals in a typical shale gas exploitation area: A comprehensive investigation by machine learning and geodetector models. CHEMOSPHERE 2024; 347:140724. [PMID: 37972868 DOI: 10.1016/j.chemosphere.2023.140724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 11/02/2023] [Accepted: 11/12/2023] [Indexed: 11/19/2023]
Abstract
Whether a certain relationship is exist between shale gas exploitation and accumulation of trace metals in soil is a controversial issue in recent years. To date, few study clearly reveal the intrinsic contributions of natural and anthropogenic factors to accumulation of trace metals in soil. In this study, machine learning and geodetector models were integrated to investigate to contribution of environmental factors to variations of trace metals concentration. Before modeling, there are 10.33%-25.87% of soil considered as metal pollution, and the value of Pn further suggest that the Ba contribute the most to the comprehensive pollution index of trace metals in soil. The initial prediction of trace metals concentration by machine learning models is less effectively indicating the need for alternative approaches. To address this problem, post-constraints approach was used, and the post-constraint MSLR model demonstrates superior performance (R2 = 0.81) Additionally, through the utilization of geodetector model, the explanatory power (q) of CEC and SOM were identified as dominant natural factors with value of 0.055 and 0.089. respectively. Moreover, distance from working sites and working status were identified as the dominant anthropogenic factors associating to the spatial heterogeneity of trace metals in soil. The interaction between natural and anthropogenic factors showed a siginifacnt nonlinear enhancement effect on accumulation of Cr, Ba and Sr, and the highest value of q was 0.38 for SOM and distance. This study indicated that the potential metal contamination was related to shale gas exploitation and provide reference for controlling soil pollution in shale gas exploitation area and making management strategy.
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Affiliation(s)
- Hongcheng Bai
- School of Architecture and Civil Engineering, Chengdu University, Chengdu, Sichuan, 610106, China; State Key Laboratory of Coal Mine Disaster Dynamics and Control, Department of Environmental Science, Chongqing University, 400045, China; Sichuan Provincial Engineering Research Center of City Solid Waste Energy and Building Materials Conversion and Utilization Technology, China.
| | - Yan Li
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Department of Environmental Science, Chongqing University, 400045, China
| | - Peili Lu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Department of Environmental Science, Chongqing University, 400045, China.
| | - Yutong Li
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Department of Environmental Science, Chongqing University, 400045, China
| | - Lilan Zhang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Department of Environmental Science, Chongqing University, 400045, China
| | - Daijun Zhang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Department of Environmental Science, Chongqing University, 400045, China
| | - Xing Wang
- College of International Studies, Yibin University, Yibin, Sichuan, 644000, China
| | - Yuxiao Zhou
- School of Food and Biological Engineering, Chengdu University, Chengdu, 610106, China
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3
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Li Y, Bai H, Li Y, Zhang X, Zhang L, Zhang D, Xu M, Zhang H, Lu P. An integrated approach to identify the source apportionment of potentially toxic metals in shale gas exploitation area soil, and the associated ecological and human health risks. JOURNAL OF HAZARDOUS MATERIALS 2023; 458:132006. [PMID: 37453347 DOI: 10.1016/j.jhazmat.2023.132006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 06/07/2023] [Accepted: 07/04/2023] [Indexed: 07/18/2023]
Abstract
Public awareness of the potential environmental risks of shale gas extraction has increased in recent years. However, the status and environmental risks of potentially toxic metals (PTMs) in shale gas field soil remain unclear. A total of 96 topsoil samples were collected from the first shale gas exploitation area in China. The sources of nine PTMs in the soils were identified using positive matrix factorization and correlation analysis, and the ecological and human health risks of toxic metals from different sources under the two land use types were calculated. The results showed that mean pollution load index (PLI) values for farmland (1.18) and woodland (1.40) indicated moderate pollution, As, Cd and Ni were the most serious contaminants among all nine PTMs. The following four sources were identified: shale gas extraction activities (43.90%), nature sources (31.90%), agricultural and traffic activities (17.55%) and industrial activities (6.55%). For ecological risk, the mean ecological risk index (RI) values for farmlands (161.95) and woodlands (185.27) reaching considerable risk. The contribution ratio of shale gas extraction activities for farmlands and woodlands were 5.70% and 8.90%, respectively. Regarding human health risk, noncarcinogenic risks for adults in farmlands and woodlands were negligible. Industrial activities, agricultural and traffic activities were estimated to be the important sources of health risks. Overall, shale gas extraction activities had little impact on the ecological and human health risk. This study provides scientific evidence regarding the soil contamination potential of shale gas development activities.
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Affiliation(s)
- Yan Li
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China
| | - Hongcheng Bai
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; School of Architecture and Civil Engineering, Chengdu University, Chengdu 610106, Sichuan, China
| | - Yutong Li
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China; Chongqing Academy of Eco-environmental Science, Chongqing 401147, China
| | - Xin Zhang
- The Key Laboratory of GIS Application and Research, Chongqing Normal University, Chongqing 401331, China
| | - Lilan Zhang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China
| | - Daijun Zhang
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China
| | - Min Xu
- Department of Environmental Science, College of Sichuan Agricultural University, Chengdu 611130, China
| | - Hong Zhang
- The Key Laboratory of GIS Application and Research, Chongqing Normal University, Chongqing 401331, China
| | - Peili Lu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing 400044, China.
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Wu F, Zhou Z, Zhang S, Cheng F, Tong Y, Li L, Zhang B, Zeng X, Li H, Wang D, Yu Z, You J. Toxicity identification evaluation for hydraulic fracturing flowback and produced water during shale gas exploitation in China: Evidence from tissue residues and gene expression. WATER RESEARCH 2023; 241:120170. [PMID: 37290192 DOI: 10.1016/j.watres.2023.120170] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 05/31/2023] [Accepted: 06/02/2023] [Indexed: 06/10/2023]
Abstract
Hydraulic fracturing flowback and produced water (HF-FPW) from shale gas extraction processes is a highly complex medium with potential threats to the environment. Current research on ecological risks of FPW in China is limited, and the link between major components of FPW and their toxicological effects on freshwater organisms is largely unknown. By integrating chemical and biological analyses, toxicity identification evaluation (TIE) was used to reveal causality between toxicity and contaminants, potentially disentangling the complex toxicological nature of FPW. Here, FPW from different shale gas wells, treated FPW effluent, and a leachate from HF sludge were collected from southwest China, and TIE was applied to obtain a comprehensive toxicity evaluation in freshwater organisms. Our results showed that FPW from the same geographic zone could cause significantly different toxicity. Salinity, solid phase particulates, and organic contaminants were identified as the main contributors to the toxicity of FPW. In addition to water chemistry, internal alkanes, PAHs, and HF additives (e.g., biocides and surfactants) were quantified in exposed embryonic fish by target and non-target tissue analyses. The treated FPW failed to mitigate the toxicity associated with organic contaminants. Transcriptomic results illustrated that organic compounds induced toxicity pathways in FPW-exposed embryonic zebrafish. Similar zebrafish gene ontologies were affected between treated and untreated FPW, again confirming that sewage treatment did not effectively remove organic chemicals from FPW. Thus, zebrafish transcriptome analyses revealed organic toxicant-induced adverse outcome pathways and served as evidence for TIE confirmation in complex mixtures under data-poor scenarios.
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Affiliation(s)
- Fan Wu
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China
| | - Zhimin Zhou
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China
| | - Shaoqiong Zhang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China
| | - Fei Cheng
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China
| | - Yujun Tong
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China
| | - Liang Li
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China
| | - Biao Zhang
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xiangying Zeng
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Huizhen Li
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China
| | - Dali Wang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China
| | - Zhiqiang Yu
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Jing You
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 511443, China.
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Chen M, Yang D, Guo F, Deng R, Nie W, Li L, Yang X, Liu S, Chen Y. Which sediment fraction mainly drives microplastics aging process: Dissolved organic matter or colloids? JOURNAL OF HAZARDOUS MATERIALS 2023; 443:130310. [PMID: 36370481 DOI: 10.1016/j.jhazmat.2022.130310] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 10/19/2022] [Accepted: 10/31/2022] [Indexed: 06/16/2023]
Abstract
Riparian sediment is the last barrier preventing contaminants from polluting aquatic ecosystems. Recently, microplastics (MPs) have frequently been found in sediments. However, the MP aging process and its impact on sediments remain unknown. This study aimed to identify the key driving factors and mechanisms of riparian sediment on MPs aging behavior. The results showed that MPs surface suffered heavy breakage and the oxygen-to-carbon ratio of MPs increased by 268 % after accumulation in sediment for 214 d. The carbonyl index revealed that the degree of MP aging driven by dissolved organic matter (DOM) was 6.7-83.6 % greater than that of colloids, indicating that DOM was the key sediment fraction driving MP aging. Sunlight was an important environmental factor that enhanced MPs aging by sediment fractions, because photo-irradiated DOM produced hydroxyl and superoxide radicals to damage the MPs structure. Benzoic acid, dibenzoylmethane, and 4-heptyl-4,6-diphenyl-tetrahydro-pytan-2-one were the main products during the MP aging process under the interaction of sunlight and DOM, which showed acute toxicity to aquatic organisms and caused more severe toxicity during the chronic period. These results clearly clarify the behavior and environmental risk of MPs after accumulation in sediment, providing guide information to control MP pollution in the riparian zone.
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Affiliation(s)
- Mengli Chen
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of education, Chongqing University, Chongqing 400045, China
| | - Dongxu Yang
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of education, Chongqing University, Chongqing 400045, China
| | - Fucheng Guo
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of education, Chongqing University, Chongqing 400045, China
| | - Ruoyu Deng
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of education, Chongqing University, Chongqing 400045, China
| | - Wenbo Nie
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of education, Chongqing University, Chongqing 400045, China
| | - Lanxi Li
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of education, Chongqing University, Chongqing 400045, China
| | - Xiangyu Yang
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of education, Chongqing University, Chongqing 400045, China
| | - Shushan Liu
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of education, Chongqing University, Chongqing 400045, China
| | - Yi Chen
- College of Environment and Ecology, Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of education, Chongqing University, Chongqing 400045, China.
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6
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Jew AD, Druhan JL, Ihme M, Kovscek AR, Battiato I, Kaszuba JP, Bargar JR, Brown GE. Chemical and Reactive Transport Processes Associated with Hydraulic Fracturing of Unconventional Oil/Gas Shales. Chem Rev 2022; 122:9198-9263. [PMID: 35404590 DOI: 10.1021/acs.chemrev.1c00504] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Hydraulic fracturing of unconventional oil/gas shales has changed the energy landscape of the U.S. Recovery of hydrocarbons from tight, hydraulically fractured shales is a highly inefficient process, with estimated recoveries of <25% for natural gas and <5% for oil. This review focuses on the complex chemical interactions of additives in hydraulic fracturing fluid (HFF) with minerals and organic matter in oil/gas shales. These interactions are intended to increase hydrocarbon recovery by increasing porosities and permeabilities of tight shales. However, fluid-shale interactions result in the dissolution of shale minerals and the release and transport of chemical components. They also result in mineral precipitation in the shale matrix, which can reduce permeability, porosity, and hydrocarbon recovery. Competition between mineral dissolution and mineral precipitation processes influences the amounts of oil and gas recovered. We review the temporal/spatial origins and distribution of unconventional oil/gas shales from mudstones and shales, followed by discussion of their global and U.S. distributions and compositional differences from different U.S. sedimentary basins. We discuss the major types of chemical additives in HFF with their intended purposes, including drilling muds. Fracture distribution, porosity, permeability, and the identity and molecular-level speciation of minerals and organic matter in oil/gas shales throughout the hydraulic fracturing process are discussed. Also discussed are analysis methods used in characterizing oil/gas shales before and after hydraulic fracturing, including permeametry and porosimetry measurements, X-ray diffraction/Rietveld refinement, X-ray computed tomography, scanning/transmission electron microscopy, and laboratory- and synchrotron-based imaging/spectroscopic methods. Reactive transport and spatial scaling are discussed in some detail in order to relate fundamental molecular-scale processes to fluid transport. Our review concludes with a discussion of potential environmental impacts of hydraulic fracturing and important knowledge gaps that must be bridged to achieve improved mechanistic understanding of fluid transport in oil/gas shales.
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Affiliation(s)
- Adam D Jew
- DOE EFRC─Center for Mechanistic Control of Water-Hydrocarbon-Rock Interactions in Unconventional and Tight Oil Formations, Stanford University, Stanford, California 94305, United States.,Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
| | - Jennifer L Druhan
- DOE EFRC─Center for Mechanistic Control of Water-Hydrocarbon-Rock Interactions in Unconventional and Tight Oil Formations, Stanford University, Stanford, California 94305, United States.,Departments of Geology and Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Matthias Ihme
- DOE EFRC─Center for Mechanistic Control of Water-Hydrocarbon-Rock Interactions in Unconventional and Tight Oil Formations, Stanford University, Stanford, California 94305, United States.,Department of Mechanical Engineering, Stanford University, Stanford, California 94305, United States
| | - Anthony R Kovscek
- DOE EFRC─Center for Mechanistic Control of Water-Hydrocarbon-Rock Interactions in Unconventional and Tight Oil Formations, Stanford University, Stanford, California 94305, United States.,Department of Energy Resources Engineering, School of Earth, Energy and Environmental Sciences, Stanford University, Stanford, California 94305-2220, United States
| | - Ilenia Battiato
- DOE EFRC─Center for Mechanistic Control of Water-Hydrocarbon-Rock Interactions in Unconventional and Tight Oil Formations, Stanford University, Stanford, California 94305, United States.,Department of Energy Resources Engineering, School of Earth, Energy and Environmental Sciences, Stanford University, Stanford, California 94305-2220, United States
| | - John P Kaszuba
- Department of Geology and Geophysics and School of Energy Resources, University of Wyoming, Laramie, Wyoming 82071, United States
| | - John R Bargar
- DOE EFRC─Center for Mechanistic Control of Water-Hydrocarbon-Rock Interactions in Unconventional and Tight Oil Formations, Stanford University, Stanford, California 94305, United States.,Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
| | - Gordon E Brown
- DOE EFRC─Center for Mechanistic Control of Water-Hydrocarbon-Rock Interactions in Unconventional and Tight Oil Formations, Stanford University, Stanford, California 94305, United States.,Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States.,Department of Geological Sciences, School of Earth, Energy and Environmental Sciences, Stanford University, Stanford, California 94305-2115, United States
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7
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Hill CB, Yadav OP, Khan E. Examining hydraulic fracturing chemicals: A temporal and comparative analysis. WATER RESEARCH 2022; 208:117878. [PMID: 34837809 DOI: 10.1016/j.watres.2021.117878] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 11/14/2021] [Accepted: 11/15/2021] [Indexed: 06/13/2023]
Abstract
Hydraulic fracturing (HF) remains a current global energy policy issue, and understanding risks to drinking water resources from HF chemicals is an important aspect of this topic. The quantity and quality of disclosed HF chemical information are significant barriers for stakeholders attempting to perform systemic environmental and public health research. A repeatable approach for processing HF chemical disclosure data is provided using United States FracFocus data as a case study. We fill research gaps by examining HF chemical trends between 2014 and 2020 and comparing HF chemicals with a list of reference chemicals known or suspected to be in contact (unrelated to HF) with drinking water, food, or cosmetics. In total, 1,244 unique HF chemicals were identified. Compared with EPA's 2016 HF chemical disclosure research, 480 new chemicals are identified, and 318 previously reported chemicals were not observed. The annual unique chemical counts have dropped from 878 to 594 (32.3%) over the research period, while data quality and transparency have increased. Approximately 69.7% of the identified HF ingredients were found in a list of reference chemicals known or suspected to be in contact (unrelated to HF) with drinking water, food, or cosmetics. Chemical differences between production types (gas and oil) and states are also reviewed. Our research reveals that the sociotechnical system surrounding HF is dynamic and moving toward fewer and, in general, safer chemicals, for those that are disclosed. This study highlights opportunities for new and updated systemic research regarding HF chemical hazard dynamics and associated risk to drinking water resources.
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Affiliation(s)
- Christopher B Hill
- Department of Civil and Environmental Engineering, North Dakota State University, Fargo, ND 58108, United States.
| | - Om P Yadav
- Department of Industrial and Manufacturing Engineering, North Dakota State University, Fargo, ND 58108, United States; Department of Industrial and Systems Engineering, North Carolina Agricultural and Technical State University, Greensboro, NC 27411, United States.
| | - Eakalak Khan
- Department of Civil and Environmental Engineering and Construction, University of Nevada, Las Vegas, Las Vegas, NV 89154-4015, United States.
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8
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Labrecque SP, Blanford WJ. Fate and transport of bromide and mononuclear aromatic hydrocarbons in aqueous solutions through Berea Sandstone. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 766:141714. [PMID: 33172637 DOI: 10.1016/j.scitotenv.2020.141714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 08/13/2020] [Accepted: 08/13/2020] [Indexed: 06/11/2023]
Abstract
A series of miscible displacement tests were performed on a 51 mm wide by 76 mm long well-laminated core of Berea Sandstone to determine the transport parameters of the anion bromide and a homologous series of seventeen mononuclear aromatic hydrocarbons (MAHs). In each test, a continuous input pulse of a single tracer was passed through the cylindrical core housed in a hydrostatic core holder at a confining pressure of 200 bar. The effluent concentration, as measured by in-line UV absorbance, versus time resulted in smooth high-resolution sinusoidal breakthrough curves (BTCs). In comparison to the near Gaussian BTCs of bromide, the transport of the MAHs was differentially retarded with minimal levels of delayed transport along the more rapid flow lines, but with progressively more along the slower flow paths. These results show that despite a lack of significant hydraulic heterogeneity, there is a high degree of heterogeneity among the sorption sites. The BTCs were aptly modeled with a one-dimensional flow model consisting of a mixture of instantaneous equilibrium and rate-limited reversible sorption sites. The relative fraction of instantaneous sites increased proportionately with the rate the subject MAH passed through the core. Potential quantitative structure-retention relationships (QSRR) between common chemical parameters of the MAHs and their overall retardation factors, sorption coefficients and the fraction of instantaneous equilibrium were evaluated. Among the compounds examined, relatively strong correlations were found with molecular weight, aqueous solubility, and octanol-water partitioning coefficient with which relative MAH transport retardation, the linear phase distribution coefficient, and the dimensionless partitioning coefficient between sorption sites.
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Affiliation(s)
- Steven P Labrecque
- School of Earth and Environmental Sciences, Queens College, City University of New York, Flushing, New York 11367, USA
| | - William J Blanford
- School of Earth and Environmental Sciences, Queens College, City University of New York, Flushing, New York 11367, USA; Earth and Environmental Sciences, The Graduate Center, 365 Fifth Avenue, New York, NY 10016, USA.
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9
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Review on the Evaluation of the Impacts of Wastewater Disposal in Hydraulic Fracturing Industry in the United States. TECHNOLOGIES 2020. [DOI: 10.3390/technologies8040067] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
This paper scrutinized hydraulic fracturing applications mainly in the United States with regard to both groundwater and surface water contamination with the purpose of bringing forth objective analysis of research findings. Results from previous studies are often unconvincing due to the incomplete database of chemical additives; after and before well-founded water samples to define the change in parameters; and specific sources of water pollution in a particular region. Nonetheless, there is a superior chance of both surface and groundwater contamination induced by improper and less monitored wastewater disposal and management practices. This report has documented systematic evidence for total dissolved solids, salinity, and methane contamination regarding drinking water correlated with hydraulic fracturing. Methane concentrations were found on an average rate of 19.2 mg/L, which is 17 times higher than the acceptance rate and the maximum value was recorded as 64.2 mg/L near the active hydraulic fracturing drilling and extraction zones than that of the nonactive sites (1.1 mg/L). The concentration of total dissolved solids (350 g/L) was characterized as a voluminous amount of saline wastewater, which was quite unexpectedly high. The paper concludes with plausible solutions that should be implemented to avoid further contamination.
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10
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Sumner AJ, Plata DL. A geospatially resolved database of hydraulic fracturing wells for chemical transformation assessment. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2020; 22:945-955. [PMID: 32037427 DOI: 10.1039/c9em00505f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Hydraulically fractured wells with horizontal drilling (HDHF) accounted for 69% of all oil and gas wells drilled and 670 000 of the 977 000 producing wells in 2016. However, only 238 flowback and produced water samples have been analyzed to date for specific organic chemicals. To aid the development of predictive tools, we constructed a database combining additive disclosure reports and physicochemical conditions at respective well sites with the goal of making synthesized analyses accessible. As proof-of-concept, we used this database to evaluate transformation pathways through two case studies: (1) a filter-based approach for flagging high-likelihood halogenation sites according to experimental criteria (e.g., for a model compound, cinnamaldehyde) and (2) a semi-quantitative, regionally comparative trihalomethane formation model that leverages an empirically derived equation. Study (1) highlighted 173 wells with high cinnamaldehyde halogenation likelihood based on combined criteria related to subsurface conditions and oxidant additive usage. Study (2) found that trihalomethane formation in certain wells within five specific basins may exceed regulatory limits for drinking water based on reaction-favorable subsurface conditions, albeit with wide uncertainty. While experimentation improves our understanding of subsurface reaction pathways, this database has immediate applications for informing environmental monitors and engineers about potential transformation products in residual fluids, guiding well operators' decisions to avoid unwanted transformations. In the future, we envision more robust components incorporating transformation, transport, toxicity, and other physicochemical parameters to predict subsurface interactions and flowback composition.
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Affiliation(s)
- Andrew J Sumner
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520, USA
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Danforth C, Chiu WA, Rusyn I, Schultz K, Bolden A, Kwiatkowski C, Craft E. An integrative method for identification and prioritization of constituents of concern in produced water from onshore oil and gas extraction. ENVIRONMENT INTERNATIONAL 2020; 134:105280. [PMID: 31704566 PMCID: PMC7547527 DOI: 10.1016/j.envint.2019.105280] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 09/16/2019] [Accepted: 10/19/2019] [Indexed: 05/14/2023]
Abstract
In the United States, onshore oil and gas extraction operations generate an estimated 900 billion gallons of produced water annually, making it the largest waste stream associated with upstream development of petroleum hydrocarbons. Management and disposal practices of produced water vary from deep well injection to reuse of produced water in agricultural settings. However, there is relatively little information with regard to the chemical or toxicological characteristics of produced water. A comprehensive literature review was performed, screening nearly 16,000 published articles, and identifying 129 papers that included data on chemicals detected in produced water. Searches for information on the potential ecotoxicological or mammalian toxicity of these chemicals revealed that the majority (56%) of these compounds have not been a subject of safety evaluation or mechanistic toxicology studies and 86% lack data to be used to complete a risk assessment, which underscores the lack of toxicological information for the majority of chemical constituents in produced water. The objective of this study was to develop a framework to identify potential constituents of concern in produced water, based on available and predicted toxicological hazard data, to prioritize these chemicals for monitoring, treatment, and research. In order to integrate available evidence to address gaps in toxicological hazard on the chemicals in produced water, we have catalogued available information from ecological toxicity studies, toxicity screening databases, and predicted toxicity values. A Toxicological Priority Index (ToxPi) approach was applied to integrate these various data sources. This research will inform stakeholders and decision-makers on the potential hazards in produced water. In addition, this work presents a method to prioritize compounds that, based on hazard and potential exposure, may be considered during various produced water reuse strategies to reduce possible human health risks and environmental impacts.
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Affiliation(s)
- Cloelle Danforth
- Environmental Defense Fund, 2060 Broadway, Suite 300, Boulder, CO 80302, USA.
| | - Weihsueh A Chiu
- Department of Veterinary Integrative Biosciences, Texas A&M University, 4458 TAMU, College Station, TX 77843, USA.
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, 4458 TAMU, College Station, TX 77843, USA.
| | - Kim Schultz
- The Endocrine Disruption Exchange, PO Box 54, Eckert, CO 81418, USA.
| | - Ashley Bolden
- The Endocrine Disruption Exchange, PO Box 54, Eckert, CO 81418, USA.
| | - Carol Kwiatkowski
- The Endocrine Disruption Exchange, PO Box 54, Eckert, CO 81418, USA.
| | - Elena Craft
- Environmental Defense Fund, 301 Congress Ave #1300, Austin, TX 78701, USA.
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12
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Ortega MF, García-Martínez MJ, Bolonio D, Canoira L, Llamas JF. Weighted linear models for simulation and prediction of biodegradation in diesel polluted soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 686:580-589. [PMID: 31185405 DOI: 10.1016/j.scitotenv.2019.05.441] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 05/27/2019] [Accepted: 05/29/2019] [Indexed: 06/09/2023]
Abstract
The purpose of this research is to find a mathematical model based on a statistical analysis to predict the evolution of the total petroleum hydrocarbons (TPH) concentrations with time in the bioremediation process of diesel contaminated soils. The analysis is useful to compare and ascertain the efficiency of different remediation treatments and the influence of both soil characteristics and initial concentration levels of hydrocarbons on the biodegradation process. An experimental design, considering two types of soil, two concentration levels of hydrocarbons and six different amendments was carried out. A total of 336 laboratory tests were conducted during a year in 48 land plots of 4×4m, spreading over eight field campaigns. The results show, for the first time to the best of our knowledge, that the bioremediation process can be adjusted quantitatively to an exponential model, following a first-order kinetic equation. The model explains correctly the higher efficiency of some treatments. In the case of hydrocarbon concentrations <16,000mg/kg, it is advisable to use slow-release fertilizer without the use of surfactant; whereas, for concentrations above 30,000mg/kg, the addition of surfactants improves the results considerably.
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Affiliation(s)
- Marcelo F Ortega
- Department of Energy & Fuels, E.T.S. Ingenieros de Minas y Energía, Universidad Politécnica de Madrid, Ríos Rosas 21, 28003 Madrid, Spain.
| | - María-Jesús García-Martínez
- Department of Energy & Fuels, E.T.S. Ingenieros de Minas y Energía, Universidad Politécnica de Madrid, Ríos Rosas 21, 28003 Madrid, Spain
| | - David Bolonio
- Department of Energy & Fuels, E.T.S. Ingenieros de Minas y Energía, Universidad Politécnica de Madrid, Ríos Rosas 21, 28003 Madrid, Spain
| | - Laureano Canoira
- Department of Energy & Fuels, E.T.S. Ingenieros de Minas y Energía, Universidad Politécnica de Madrid, Ríos Rosas 21, 28003 Madrid, Spain
| | - Juan F Llamas
- Department of Energy & Fuels, E.T.S. Ingenieros de Minas y Energía, Universidad Politécnica de Madrid, Ríos Rosas 21, 28003 Madrid, Spain
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13
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Sumner AJ, Plata DL. Oxidative Breakers Can Stimulate Halogenation and Competitive Oxidation in Guar-Gelled Hydraulic Fracturing Fluids. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:8216-8226. [PMID: 31276388 DOI: 10.1021/acs.est.9b01896] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A number of flowback samples derived from horizontally drilled hydraulic fracturing (HDHF) operations reveal consistent detections of halogenated organic species , yet the source of these compounds remains uncertain. Studies simulating subsurface conditions have found that oxidative "breakers" can halogenate certain additives, but these pathways are unverified in the presence of cross-linked-gels, common features of HDHF operations. Using a high-throughput custom reactor system, we implemented a reaction matrix to test the capacity for halogenation of two frequently disclosed compounds with demonstrated halogenation pathways (cinnamaldehyde and citric acid) across guar gels with varied types and concentrations of cross-linkers and oxidative breakers. Cinnamaldehyde halogenation proceeded most readily in borate cross-linked gels at high ammonium persulfate dosages. Citric acid formed trihalomethanes (THMs) broadly across the matrix, generating brominated THMs at higher levels of hypochlorite breaker. Isolated removals of cross-linker or guar enhanced or diminished certain product formations, highlighting additional capacities for relevant ingredients to influence halogenation. Finally, we analyzed flowback samples from the Denver-Julesberg Basin, finding that additions of oxidant enhanced halogenation. As a more realistic subsurface simulation, this work demonstrates strict criteria for the subsurface halogenation of cinnamaldehyde and the broad capacity for THM formation due to systematic oxidant usage as gel breakers in HDHF operations.
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Affiliation(s)
- Andrew J Sumner
- Department of Chemical and Environmental Engineering , Yale University , New Haven , Connecticut 06520 , United States
| | - Desiree L Plata
- Department of Chemical and Environmental Engineering , Yale University , New Haven , Connecticut 06520 , United States
- Department of Civil and Environmental Engineering , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
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14
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Faber AH, Annevelink M, Gilissen HK, Schot P, van Rijswick M, de Voogt P, van Wezel A. How to Adapt Chemical Risk Assessment for Unconventional Hydrocarbon Extraction Related to the Water System. REVIEWS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2019; 246:1-32. [PMID: 29280081 DOI: 10.1007/398_2017_10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We identify uncertainties and knowledge gaps of chemical risk assessment related to unconventional drillings and propose adaptations. We discuss how chemical risk assessment in the context of unconventional oil and gas (UO&G) activities differs from conventional chemical risk assessment and the implications for existing legislation. A UO&G suspect list of 1,386 chemicals that might be expected in the UO&G water samples was prepared which can be used for LC-HRMS suspect screening. We actualize information on reported concentrations in UO&G-related water. Most information relates to shale gas operations, followed by coal-bed methane, while only little is available for tight gas and conventional gas. The limited research on conventional oil and gas recovery hampers comparison whether risks related to unconventional activities are in fact higher than those related to conventional activities. No study analyzed the whole cycle from fracturing fluid, flowback and produced water, and surface water and groundwater. Generally target screening has been used, probably missing contaminants of concern. Almost half of the organic compounds analyzed in surface water and groundwater exceed TTC values, so further risk assessment is needed, and risks cannot be waived. No specific exposure scenarios toward groundwater aquifers exist for UO&G-related activities. Human errors in various stages of the life cycle of UO&G production play an important role in the exposure. Neither at the international level nor at the US federal and the EU levels, specific regulations for UO&G-related activities are in place to protect environmental and human health. UO&G activities are mostly regulated through general environmental, spatial planning, and mining legislation.
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Affiliation(s)
- Ann-Hélène Faber
- Copernicus Institute of Sustainable Development, Faculty of Geosciences, Utrecht University, Utrecht, The Netherlands.
- KWR Watercycle Research Institute, Nieuwegein, The Netherlands.
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands.
| | - Mark Annevelink
- KWR Watercycle Research Institute, Nieuwegein, The Netherlands
- Department of Environmental Science, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Herman Kasper Gilissen
- Utrecht Centre for Water, Oceans and Sustainability Law, Faculty of Law, Economics and Governance, Utrecht University, Utrecht, The Netherlands
| | - Paul Schot
- Copernicus Institute of Sustainable Development, Faculty of Geosciences, Utrecht University, Utrecht, The Netherlands
| | - Marleen van Rijswick
- Utrecht Centre for Water, Oceans and Sustainability Law, Faculty of Law, Economics and Governance, Utrecht University, Utrecht, The Netherlands
| | - Pim de Voogt
- KWR Watercycle Research Institute, Nieuwegein, The Netherlands
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Annemarie van Wezel
- Copernicus Institute of Sustainable Development, Faculty of Geosciences, Utrecht University, Utrecht, The Netherlands
- KWR Watercycle Research Institute, Nieuwegein, The Netherlands
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He Y, Zhang Y, Martin JW, Alessi DS, Giesy JP, Goss GG. In vitro assessment of endocrine disrupting potential of organic fractions extracted from hydraulic fracturing flowback and produced water (HF-FPW). ENVIRONMENT INTERNATIONAL 2018; 121:824-831. [PMID: 30342413 DOI: 10.1016/j.envint.2018.10.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 09/11/2018] [Accepted: 10/10/2018] [Indexed: 06/08/2023]
Abstract
Potential effects of horizontal drilling combined with high-volume hydraulic fracturing (HF) have drawn significant public concern, especially on the handling, treatment, and disposal of HF flowback and produced water (HF-FPW). Previous studies indicated HF-FPW could significantly disrupt biotransformation and expressions of genes related to the endocrine system. This study focused on effects of organic extracts of HF-FPW on receptor binding activity using several transactivation assays. Six HF-FPW samples were collected from 2 wells (Well A and Well B, 3 time points at each well). These were separated by filtration into aqueous (W) and particulate (S) phases, and organics were extracted from all 12 subsamples. Of all the tested fractions, sample B1-S had the greatest Σ13PAH (11,000 ng/L) and B3-S has the greatest Σ4alkyl-PAHs (16,000 ng/L). Nuclear receptor binding activity of all the extracts on aryl hydrocarbon receptor (AhR), estrogen receptor (ER), and androgen receptor (AR) were screened using H4IIE-luc, MVLN-luc, and MDA-kb2 cells, respectively. FPWs from various HF wells exhibited distinct nuclear receptor binding effects. The strongest AhR agonist activity was detected in B3-S, with 450 ± 20 μg BaP/L equivalency at 5 × exposure. The greatest ER agonist activity was detected in A1-W, with 5.3 ± 0.9 nM E2 equivalency at 10× exposures. There is a decreasing trend in ER agonist activity from A1 to A3 in both aqueous and particulate fractions from Well A, while there is an increasing trend in ER agonist activity from B1 to B3 in aqueous fractions from Well B. This study provides novel information on the sources of endocrine disruptive potentials in various HF-FPW considering both temporal and spatial variability. Results suggest that reclamation or remediation and risk assessment of HF-FPW spills likely requires multiple strategies including understanding the properties of each spill with respect to fractured geological formation and physiochemical properties of the injected fluid.
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Affiliation(s)
- Yuhe He
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada.
| | - Yifeng Zhang
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta T6G 2G3, Canada
| | - Jonathan W Martin
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta T6G 2G3, Canada
| | - Daniel S Alessi
- Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada
| | - John P Giesy
- Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, Canada; State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; Global Institute for Water Security, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Greg G Goss
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada.
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16
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Kondash AJ, Lauer NE, Vengosh A. The intensification of the water footprint of hydraulic fracturing. SCIENCE ADVANCES 2018; 4:eaar5982. [PMID: 30116777 PMCID: PMC6093634 DOI: 10.1126/sciadv.aar5982] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 06/26/2018] [Indexed: 05/25/2023]
Abstract
Unconventional oil and gas exploration in the United States has experienced a period of rapid growth, followed by several years of limited production due to falling and low natural gas and oil prices. Throughout this transition, the water use for hydraulic fracturing and wastewater production in major shale gas and oil production regions has increased; from 2011 to 2016, the water use per well increased up to 770%, while flowback and produced water volumes generated within the first year of production increased up to 1440%. The water-use intensity (that is, normalized to the energy production) increased ubiquitously in all U.S. shale basins during this transition period. The steady increase of the water footprint of hydraulic fracturing with time implies that future unconventional oil and gas operations will require larger volumes of water for hydraulic fracturing, which will result in larger produced oil and gas wastewater volumes.
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17
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Ma L, Hurtado A, Eguilior S, Llamas Borrajo JF. A model for predicting organic compounds concentration change in water associated with horizontal hydraulic fracturing. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 625:1164-1174. [PMID: 29996413 DOI: 10.1016/j.scitotenv.2017.12.273] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 12/22/2017] [Accepted: 12/22/2017] [Indexed: 06/08/2023]
Abstract
Horizontal drilling and hydraulic fracturing are technologies designed to increase natural gas flow and to improve productivity in low permeability formations. During this drilling operation, tons of flowback and produced water, which contain several organic compounds, return to the surface with a potential risk of influencing the surrounding environment and human health. In order to conduct predictive risk assessments a mathematical model is needed to evaluate organic compound behaviour along the water transportation process as well as concentration changes over time throughout the operational life cycle. A comprehensive model, which fits the experimental data, combining an Organic Matter Transport Dynamic Model with a Two-Compartment First-order Rate Constant (TFRC) Model has been established to quantify the organic compounds concentrations. This algorithm model incorporates two transportation rates, fast and slow. The results show that the higher the value of the organic carbon partition coefficient (koc) in chemicals, the later the maximum concentration in water will be reached. The maximum concentration percentage would reach up to 90% of the available concentration of each compound in shale formation (whose origin may be associated to drilling fluid, connate water and/or rock matrix) over a sufficiently long period of time. This model could serve as a contribution to enhance monitoring strategy, increase benefits out of optimizing health risk assessment for local residents and provide initial baseline data to further operations.
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Affiliation(s)
- Lanting Ma
- Escuela Técnica Superior de Ingenieros de Minas y Energía de Madrid, Calle de Ríos Rosas 21, 28003 Madrid, Spain.
| | - Antonio Hurtado
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, Avda. Complutense 40, Edif. 20, 28040 Madrid, Spain
| | - Sonsoles Eguilior
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, Avda. Complutense 40, Edif. 20, 28040 Madrid, Spain
| | - Juan F Llamas Borrajo
- Escuela Técnica Superior de Ingenieros de Minas y Energía de Madrid, Calle de Ríos Rosas 21, 28003 Madrid, Spain
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Rosenblum J, Thurman EM, Ferrer I, Aiken G, Linden KG. Organic Chemical Characterization and Mass Balance of a Hydraulically Fractured Well: From Fracturing Fluid to Produced Water over 405 Days. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:14006-14015. [PMID: 29132208 DOI: 10.1021/acs.est.7b03362] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A long-term field study (405 days) of a hydraulically fractured well from the Niobrara Formation in the Denver-Julesburg Basin was completed. Characterization of organic chemicals used in hydraulic fracturing and their changes through time, from the preinjected fracturing fluid to the produced water, was conducted. The characterization consisted of a mass balance by dissolved organic carbon (DOC), volatile organic analysis by gas chromatography/mass spectrometry, and nonvolatile organic analysis by liquid chromatography/mass spectrometry. DOC decreased from 1500 mg/L in initial flowback to 200 mg/L in the final produced water. Only ∼11% of the injected DOC returned by the end of the study, with this 11% representing a maximum fraction returned since the formation itself contributes DOC. Furthermore, the majority of returning DOC was of the hydrophilic fraction (60-85%). Volatile organic compound analysis revealed substantial concentrations of individual BTEX compounds (0.1-11 mg/L) over the 405-day study. Nonvolatile organic compounds identified were polyethylene glycols (PEGs), polypropylene glycols (PPG), linear alkyl-ethoxylates, and triisopropanolamine (TIPA). The distribution of PEGs, PPGs, and TIPA and their ubiquitous presence in our samples and the literature illustrate their potential as organic tracers for treatment operations or in the event of an environmental spill.
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Affiliation(s)
| | | | | | - George Aiken
- U.S. Geological Survey, Boulder, Colorado 80309, United States
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Kondash AJ, Albright E, Vengosh A. Quantity of flowback and produced waters from unconventional oil and gas exploration. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 574:314-321. [PMID: 27639468 DOI: 10.1016/j.scitotenv.2016.09.069] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 09/08/2016] [Accepted: 09/09/2016] [Indexed: 06/06/2023]
Abstract
The management and disposal of flowback and produced waters (FP water) is one of the greatest challenges associated with unconventional oil and gas development. The development and production of unconventional natural gas and oil is projected to increase in the coming years, and a better understanding of the volume and quality of FP water is crucial for the safe management of the associated wastewater. We analyzed production data using multiple statistical methods to estimate the total FP water generated per well from six of the major unconventional oil and gas formations in the United States. The estimated median volume ranges from 1.7 to 14.3millionL (0.5 to 3.8milliongal) of FP per well over the first 5-10years of production. Using temporal volume production and water quality data, we show a rapid increase of the salinity associated with a decrease of FP production rates during the first months of unconventional oil and gas production. Based on mass-balance calculations, we estimate that only 4-8% of FP water is composed of returned hydraulic fracturing fluids, while the remaining 92-96% of FP water is derived from naturally occurring formation brines that is extracted together with oil and gas. The salinity and chemical composition of the formation brines are therefore the main limiting factors for beneficial reuse of unconventional oil and gas wastewater.
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Affiliation(s)
- Andrew J Kondash
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
| | - Elizabeth Albright
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
| | - Avner Vengosh
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA.
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