Removing a small quantity of THT from gas storage groundwater through air stripping and gas-phase carbon adsorption

This paper deals with the response to a case of contaminated groundwater located in France, The natural gas is stored during summer in porous underground rocks. When energy requirements increase (Particularly in winter), gas is drawn off, but water is also pumped during this operation. The water has a strong characteristic odour of the TetraHydroThiophene (THT), which has been used by Gaz de France as an additive in order to detect gas leakages because of its strong odour. Unfortunately, the presence of THT in medium other than natural gas can be responsible for safety problems. Gas stripping combined with adsorption on granular activated carbon was chosen to obtain removal of THT from the groundwater. The gas to water ratio for stripping column is higher than usual and the gas used for strip ping was recycled in order to prevent air pollution. Carbon consumption is approximately 3 tons a year.