| abstract |
The invention relates to a process for the simultaneous recovery of biomass and aging-stable Erdoelfraktionen, preferably Grundoelen for transformer oils, by biological Teilentparaffinierung. After the biological treatment, the non-biologically converted part of the petroleum fraction is purified by means of phosphoric acid to remove the substances which have an adverse effect on the aging behavior. The phosphoric acid from this purification is used as a source of phosphorus for the biological treatment step by adding to the phosphoric acid alkali or ammonia, preferably potassium hydroxide, until a p H in the range of 4 to 6, preferably 4.5 to 5.5, is reached. After separation of the separating organic phase, the aqueous, phosphate-containing solution is used for the preparation of the nutrient solution for the biological treatment stage. |