Landfill gas-powered atmospheric water harvesting for oilfield operations in the United States

- Landfill gas-powered dehumidification of air is a new utilization technology.
- Technology can supply freshwater to nearby oilfields in the US.
- Technology is attractive for Barnett Shale (TX) and Kern County oilfields (CA).
- Technology can meet 34% and 12-26% of water requirements of Barnett and Kern County oilfields.
- Technology can reduce venting/flaring of methane by 65%.

Landfill gas accounts for 18% of US greenhouse gas emissions. The energy wasted via venting/flaring methane in landfill gas can be valued at 7.5 billion USD (annually). This work presents a novel utilization concept, wherein landfill gas-powered refrigeration enables large-scale atmospheric water harvesting, via dehumidification. This work analyzes the potential of landfill gas-powered atmospheric water harvesting towards meeting the water requirements of oilfields located near landfills. Heat and mass transfer-based analytical modeling is used to estimate the seasonal water harvest, and techno-economic analyses are presented to quantify the benefits for US oilfields. This technology is seen to be attractive for the Barnett Shale (Texas) and Kern County (California), which can be served by 30 landfills each, and are located in hot-humid and water-stressed areas. Results show that landfill gas-powered water harvesting can meet 34% of water requirements (hydraulic fracturing) in the Barnett Shale and 12-26% of water requirements (enhanced oil recovery) in Kern County oilfields, respectively. Landfill gas projects are economically more viable in the Barnett as compared to Kern County. The impact of landfill gas-powered water harvesting on CO2e emissions from landfills is quantified. Constraints and challenges associated with water harvesting are discussed. Importantly, this waste-to-value concept has worldwide relevance since landfills co-exist with population centers.