28 research outputs found

    Management of water extracted from carbon sequestration projects

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    Throughout the past decade, frequent discussions and debates have centered on the geological sequestration of carbon dioxide (CO{sub 2}). For sequestration to have a reasonably positive impact on atmospheric carbon levels, the anticipated volume of CO{sub 2} that would need to be injected is very large (many millions of tons per year). Many stakeholders have expressed concern about elevated formation pressure following the extended injection of CO{sub 2}. The injected CO{sub 2} plume could potentially extend for many kilometers from the injection well. If not properly managed and monitored, the increased formation pressure could stimulate new fractures or enlarge existing natural cracks or faults, so the CO{sub 2} or the brine pushed ahead of the plume could migrate vertically. One possible tool for management of formation pressure would be to extract water already residing in the formation where CO{sub 2} is being stored. The concept is that by removing water from the receiving formations (referred to as 'extracted water' to distinguish it from 'oil and gas produced water'), the pressure gradients caused by injection could be reduced, and additional pore space could be freed up to sequester CO{sub 2}. Such water extraction would occur away from the CO{sub 2} plume to avoid extracting a portion of the sequestered CO{sub 2} along with the formation water. While water extraction would not be a mandatory component of large-scale carbon storage programs, it could provide many benefits, such as reduction of pressure, increased space for CO{sub 2} storage, and potentially, 'plume steering.' Argonne National Laboratory is developing information for the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL) to evaluate management of extracted water. If water is extracted from geological formations designated to receive injected CO{sub 2} for sequestration, the project operator will need to identify methods for managing very large volumes of water most of which will contain large quantities of salt and other dissolved minerals. Produced water from oil and gas production also typically contains large quantities of dissolved solids. Therefore, many of the same practices that are established and used for managing produced water also may be applicable for extracted water. This report describes the probable composition of the extracted water that is removed from the formations, options for managing the extracted water, the pros and cons of those options, and some opportunities for beneficial use of the water. Following the introductory material in Chapter 1, the report is divided into chapters covering the following topics: (Chapter 2) examines the formations that are likely candidates for CO{sub 2} sequestration and provides a general evaluation of the geochemical characteristics of the formations; (Chapter 3) makes some preliminary estimates of the volume of water that could be extracted; (Chapter 4) provides a qualitative review of many potential technologies and practices for managing extracted water and for each technology or management practice, pros and cons are provided; (Chapter 5) explores the potential costs of water management; and (Chapter 6) presents the conclusions

    Hydraulic Fracturing and Shale Gas Production: Technology, Impacts, and Regulations

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    Water resource assessment of geothermal resources and water use in geopressured geothermal systems.

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    Water use in the development and operation of geothermal power plants.

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    Geothermal energy is increasingly recognized for its potential to reduce carbon emissions and U.S. dependence on foreign oil. Energy and environmental analyses are critical to developing a robust set of geothermal energy technologies. This report summarizes what is currently known about the life cycle water requirements of geothermal electric power-generating systems and the water quality of geothermal waters. It is part of a larger effort to compare the life cycle impacts of large-scale geothermal electricity generation with other power generation technologies. The results of the life cycle analysis are summarized in a companion report, Life Cycle Analysis Results of Geothermal Systems in Comparison to Other Power Systems. This report is divided into six chapters. Chapter 1 gives the background of the project and its purpose, which is to inform power plant design and operations. Chapter 2 summarizes the geothermal electricity generation technologies evaluated in this study, which include conventional hydrothermal flash and binary systems, as well as enhanced geothermal systems (EGS) that rely on engineering a productive reservoir where heat exists but water availability or permeability may be limited. Chapter 3 describes the methods and approach to this work and identifies the four power plant scenarios evaluated: a 20-MW EGS plant, a 50-MW EGS plant, a 10-MW binary plant, and a 50-MW flash plant. The two EGS scenarios include hydraulic stimulation activities within the construction stage of the life cycle and assume binary power generation during operations. The EGS and binary scenarios are assumed to be air-cooled power plants, whereas the flash plant is assumed to rely on evaporative cooling. The well field and power plant design for the scenario were based on simulations using DOE's Geothermal Economic Technology Evaluation Model (GETEM). Chapter 4 presents the water requirements for the power plant life cycle for the scenarios evaluated. Geology, reservoir characteristics, and local climate have various effects on elements such as drilling rate, the number of production wells, and production flow rates. Over the life cycle of a geothermal power plant, from construction through 30 years of operation, plant operations is where the vast majority of water consumption occurs. Water consumption refers to the water that is withdrawn from a resource such as a river, lake, or non-geothermal aquifer that is not returned to that resource. For the EGS scenarios, plant operations consume between 0.29 and 0.72 gal/kWh. The binary plant experiences similar operational consumption, at 0.27 gal/kWh. Far less water, just 0.01 gal/kWh, is consumed during operations of the flash plant because geofluid is used for cooling and is not replaced. While the makeup water requirements are far less for a hydrothermal flash plant, the long-term sustainability of the reservoir is less certain due to estimated evaporative losses of 14.5-33% of produced geofluid at operating flash plants. For the hydrothermal flash scenario, the average loss of geofluid due to evaporation, drift, and blowdown is 2.7 gal/kWh. The construction stage requires considerably less water: 0.001 gal/kWh for both the binary and flash plant scenarios and 0.01 gal/kWh for the EGS scenarios. The additional water requirements for the EGS scenarios are caused by a combination of factors, including lower flow rates per well, which increases the total number of wells needed per plant, the assumed well depths, and the hydraulic stimulation required to engineer the reservoir. Water quality results are presented in Chapter 5. The chemical composition of geofluid has important implications for plant operations and the potential environmental impacts of geothermal energy production. An extensive dataset containing more than 53,000 geothermal geochemical data points was compiled and analyzed for general trends and statistics for typical geofluids. Geofluid composition was found to vary significantly both among and within geothermal fields. Seven main chemical constituents were found to account for 95-99% of the dissolved solids in typical geofluids. In order of abundance, they were chloride, sodium, bicarbonate, sulfate, silica, calcium, and potassium. The potential for water and soil contamination from accidents and spills was analyzed by comparing geofluid composition with U.S. drinking water standards. Geofluids were found to present a potential risk to drinking water, if released, due to high concentrations of antimony, arsenic, lead, and mercury. That risk could be mitigated through proper design and engineering controls. The concentration and impact of noncondensible gases (NCG) dissolved in the geofluid was evaluated. The majority of NCG was either nitrogen or carbon dioxide, but a small number of geofluids contain potentially recoverable concentrations of hydrogen or methane

    DEVELOPMENT OF GEOSPATIAL INFORMATION INTEGRATED WITH BIG DATA TO AGRICULTURAL HAZARD MONITORING IN WEST JAVA

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    Food security is highly dependent on three aspects, namely food availability, food access, and food utilization. The availability aspect depends on food supply which is identical to agricultural productivity. West Java Province is the third national rice producer with 16.6%, but West Java Province is the most extensive rice consumer, around 21.1% of the total national rice consumption. Agricultural productivity can decline due to natural hazards such as floods and droughts. Monitoring floods and droughts in paddy fields are necessary to prevent decreased agricultural productivity. This study aims to monitor the rice fields from the dangers of flooding and drought every month. Agricultural hazard monitoring is divided into two parameters, namely static parameters and dynamic parameters. Dynamic parameters are observed every month so that the hazard index is generated on a monthly scale. GIS and Remote sensing data are integrated to perform agricultural hazard modelling. Furthermore, this agricultural hazard modelling results will be strengthened by using big to provide information about an almost real-time event that can be accessed through the Application Program Interface (API) service. This study uses a data mining system from Drone Emprit that performs data mining on Twitter and news portals with machine learning technology (probabilistic classifier) and Natural Learning Process. The results obtained are around 15,000 data from January 1 to November 1, 2021, and 37.9% of them are identified by location based on the city or district level in West Java Province. It is hoped that the policy-maker can consider the area of agricultural land that requires assistance to increase productivity and plan a policy to support agriculture in West Java in the future
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