Objectives

In order to reduce the impact of greenhouse gases on global climate change, Belgium has agreed to ratify the Kyoto protocol and reduce its industrial emissions of CO2 by 7,5% compared to the 1990 level towards 2008-2012.

In practice, this means a reduction of 25 million tonnes of CO2 whereas combined emissions of the industrial sectors targeted for reduction measures attain 55 million tonnes yearly. Current policies aim at rational use of energy (improving energy efficiency), renewable energies (current share less than 1% in Belgium, the lowest in Europe), reducing carbon intensity (switch from coal to gas which produces less CO2during combustion).
The effect of these measures is largely insufficient to reach the target set for Belgium, not counting the additional effect of phasing out of nuclear power. Therefore, capture and sequestration of CO2 will soon become a necessary option. The Geological Survey of Belgium is studying the potential for geological sequestration of CO2 in the Belgian subsurface.

Realisation

In the framework of the GESTCO project, set up by EuroGeoSurveys, and in cooperation with VITO (Flemish Institute for Technological Research), suitable underground reservoirs for storage of CO2 are selected. These are composed of deep saline aquifers, mainly the Lower Carboniferous limestone in the western Campine basin or in unmined coal beds and closed coal mines in the eastern Campine basin and the Hainaut coalfield. The latter are favoured because sequestration of CO2 will stimulate energy recycling by enhancing coal bed methane recovery or inducing new geothermal systems in deep mines. Uncertainties concerning thermodynamics of phase transitions of CO2, solution and adsorption kinetics in the relatively shallow Belgian reservoirs were addressed.
An important factor is long-term sustainability and safety of geological sequestration : comparison with seasonal storage of natural gas, practiced in the same types of reservoirs, indicates that favourable conditions can be met. Future research may be equally directed at the integrity of the Cretaceous caprock, sealing off the reservoirs, and at promoting early opportunity projects, combining low cost capture of process CO2 with high injection rates in reservoirs with high natural or human-induced permeability, even though their total storage potential may be limited.

Related activities

• Mining aftermath: environmental impact and opportunities
• AMM abandoned coal mine methane
• CBM coal bed methane recovery
• CO2 geothermics in mines
• CAES compressed air energy systems
• underground storage of heat, cold, waste, gas
• hydrocarbon exploration