Underground coal gasification: An overview of groundwater contamination hazards and mitigation strategies

Prediction of Steam Jacket Dynamics and Water Balances in Underground Coal Gasification

“…According to Camp and White [14], low coal and overburden permeabilities are preferable in view of limiting water flow into the UCG reactor, since spalling-enhanced drying of coal and roof rocks generally supplies sufficient water to feed an efficient gasification process. In this context, our modeling approach supports UCG operators to adjust reactor operating pressures to maintain the required water inflow and minimize potential fluid leakages out of the reactor.…”

“…Camp and White [14] discuss that a fingering phenomena being related to upward vapor migration is rather more likely than a continuous steam jacket front advancement in highly heterogeneous coals. However, this was not observed in our simulation results due to the applied directional homogeneous permeability distribution.…”

“…The Laramie Energy Technology Center (LERC) conducted five pilot tests at the Hanna and the Lawrence Livermore National Laboratory (LLNL) three tests at the Hoe Creek site. The well-documented results of these field tests have been presented in numerous publications and reports, e.g., [14,[44][45][46][47][48][49][50][51][52][53][54]. Yang et al [36] reviewed the recent global developments, research progress, and technical innovations as well as the economic feasibility of UCG over the past ten years.…”

“…This re-emerging technology could provide a relevant contribution to the development of Clean Coal Technologies, if accompanied by carbon capture and storage, e.g., in the reactor cavities generated in the coal following the cease of operation [4][5][6]. Apart from its high economic potentials [7][8][9], UCG may induce environmental impacts such as freshwater aquifer pollution by synthesis gas and/or by-product leakage [10][11][12][13][14][15][16].…”

An assessment of technical and economic feasibility to install geothermal well systems across Ukraine

“…This process is based on aquifer heating by burning the underlying coal seams of low thickness (Dychkovskyi 2015;Pivnyak et al 2018). The largest industrial experiment in underground coal gasification conducted in the USA at the Rocky Mountains site in 1987-1988 reported by Camp and White (2015) and Berdan (1986) demonstrated the significant potential of a creating a thermal source with the temperature exceeding 100 °C in the early stages of coal combustion. Table 1 Temperature and flow rates of thermal waters in the hydrogeological provinces across Ukraine (province boundaries can be seen on Fig.…”