Aims

The aim of this project is the evaluation of a low emission power plant based on utilization of synthetic gas from in-situ coal conversion with emphasis on free-gas and adsorptive CO2 storage in the resulting gasified coal seams. Within this evaluation, economical and environmental aspects of CO2 storage in gasified coal seams will be considered with regard to operational costs, environmental protection and CO2 storage security.

Within the scope of the formerly BMFT funded K2G (Kohlegewinnung Zweite Generation) program, European UCG investigations started with the implementation of numerous scientifically successful projects and pilot sites in the 1980s demonstrating its technical feasibility in deep coal seams. The investigation and application of UCG has been terminated in these countries due to economical reasons such as availability of low priced mineable hydrocarbons and economically mineable coal deposits. Rising prices of fossil fuels altered the economical situation on the market for energy sources in the 1990s. Therefore, new UCG efforts have been started in Australia, China, New Zealand and South Africa.

combined cycle

A differentiated consideration of long-term CO2 storage security in in-situ gasified coal seams is planned within this project. While overburden permeability is known to be low, retarding adsorptive effects resulting from its clay components considering CO2 transport have already been investigated at an experimental stage in other studies. Numerical simulations considering these parameters can reveal detailed information considering long-term CO2 migration to the surface at a large-scale UCG-CCS project.

Project goals

• Implementation of an innovative concept for CO2 storage in in-situ converted coal seams
• Evaluation of environmental impacts with regard to groundwater protection and technical approaches based on operating experience of former and current international UCG projects
• Investigation of economics of underground coal gasification and combined CO2 storage
• Estimation of CO2 storage potentials based on laboratory gasification, permeability tests and sorption experiments
• Evaluation CO2 of storage security in gasified coal seams by numerical modeling using input parameters from experimental studies conducted on coal seams and cap rocks
• Preparatory scientific work for implementation of a large-scale field test