TRATTAMENTO DI MATERIALE BIODE GRADABILE

摘要

Liq. contg. suspended or dissolved material subject to breakdown by microorganisms is treated by injecting a gas contg. oxygen. For some of the time at least part of the liq. has a low dissolved oxygen concn. (defined as the partial pressure) and/or at least part of the liq. has a high dissolved oxygen concen. so that the ratio of carbon dioxide to cellular material formed in the processed is increased. The times during which the high or low concns. are maintained is kept short enough for the influence on the microorganisms not to affect their working adversely. This is also ensured by maintaining the liq. for part of the time at inter. oxygen concns. Used for treating effluent (normally aqs) after solids have been removed. The process may be used as an aerator or as a digester. The changes in oxygen concn. select for the most desirable microorganisms.