Abstract: Water-soluble ethers used as octane number enhancers in gasoline are disturbing components in soils and groundwater even in small amounts due to their strong taste and odour. This invention relates to biological purification of gasoline-contaminated soils and groundwater, more specifically to Variovorax strains being able to degrade ethers and their degradation products and to a mixed bacterial population comprising said bacteria. Further this invention relates to a process for bacterial degradation of ethers and their degradation products and to the use of one or more Variovorax strains of the invention in purifying contaminated soil or water.

Abstract: A method of purifying waste water biologically by using three particularly suitable bacteria: Bacillus sp. DT-1, Pseudomonas azelaica, DT-2, and/or Rhizobus sp. DT-5, or mixed populations thereof. The invention further relates to the bacteria and the mixed populations and use thereof in purifying waste water. The invention further relates to a bioreactor including the bacteria.

Abstract: The invention relates to a spa water circulation system and a method of circulating spa water. The water consumption at a spa as well as at a swimming hall consists of both pool water and grey water, which is mainly shower water. Both waters are purified. The present invention provides an economical solution for purifying both these waters by circulating the waters through two purification systems which are connected to each other and through which even the filter wash waters may be circulated.