Biodestruction of lubricated motor oils in sewage water with the use of pilot biological installation

Abstract

This article presents the results of an experiment on the choice of technology for purification and final purification of wastewater of small sewage enterprises and large-scale productions from waste lubricating oils of mineral origin with a wide change in the pH of the medium, providing dissolved oxygen and biogenic elements. It is proved that a high degree of biodegradation of oil-contaminated effluents is achieved by the wide use of the newly created consortium of hydrocarbon-oxidizing microorganisms (HOM), which includes nine strains belonging to the genera: Alcaligenes(1 species), Bacillus (1 species), Brevibacterium (2 species), Clostridium (1 species), Flavobacterium (1 species), Micrococcus (1 species) and Pseudomonas (2 species). The association of this microorganismsis able to oxidize various fractions of oil ranging from n-alkalis, to asphaltenes, including mineral, semi-synthetic and synthetic oils of various origin. It has been established that the load change from 25 to 100 mg/dm3(COD from 450 to 650 mg/dm3) when using lubricating oil in stock ROB almost does not affect the degree of biodegradation of the original pollution. During the contacting of the ON-NOVO consortium with the oil-containing waste liquid in the bioreactor and further in the secondary settling tank, with a total duration of 1.5 to 4.5 hours, the degree of effluent purification reaches up to 77.4%. With the addition of a normalized amount of nutrients in the amount of 20 mg/dm3 (optimal zone), the degree of neutralization of waste water exceeds 86%. In terms of residual content of oxidized mineral oil, the cleaning intensity exceeds 94%.