Study On The Effects Of Oxygen Supply On Petroleum Hydrocarbon Biodegradation And Metabolism

When petroleum hydrocarbon pollutant is being treated by microbe, as well as the soil contaminated by petroleum hydrocarbon, the lack of oxygen often become the rate-limiting factor for biodegradation.In this article, aiming at well-drilling waste mud containing petroleum hydrocarbon pollutant, we research into the effects of oxygen supply on petroleum hydrocarbon biodegradation and metabolism, with a candida. strain named YY-12 which has been selected out as a petroleum hydrocarbon degrading strain by domesticating before. The main works and conclusions are included as fellows:(1) The experimental study of mechanism oxygen supply in different lyo-oxygen consistency showed that the higher lyo-oxygen consistency of the degradation system was, the more viable strain count and the faster degradation rate for petroleum hydrocarbon were ultimately.(2) Through the experiment in which H₂O₂ was taken as oxygen source of the degradation system , it's find that the trend of H₂O₂ decomposition and O2 release is coincident, and their velocity all become faster in higher pH than in lower. The results of toxicity experiment showed that when H₂O₂ consistency was less than 200mg/L the growth of YY-12 was insusceptible, and the tolerance capability of strains in logarithmic growth phase was better than in lag phase. Comparing with actionless degradation system without H₂O₂, the lag growth phase of YY-12 was brought forward 12 hours by taking H₂O₂ as oxygen source. H₂O₂ can steady pH change in the system especially to reduce its rising amplitude. In degradation system that H₂O₂ was added in , 96 hours later, it's find that petroleum hydrocarbon consistency drop down to 226.98mg/L from 1343.11mg/L of beginning, and the degradation rate reached to 84% while the comparison system was only 38%.There are two kinds of oxygen pipeline for H₂O₂ to supply oxygen, one is H₂O₂→O2→aqua→microbe, the other one is H₂O₂→microbe, that is to say H₂O₂ can be decompounded by the catalysis of catelase also.(3) Through the experiment in which hydrolyzed protein spume was taken as oxygen source for microbe to degrade petroleum hydrocarbon, it's find that the spumes could separate petroleum hydrocarbon from mud effectively, then adsorb those hydrocarbon and bring them to the surface layer of mud by the action of buoyancy. At...