Study On Decreasing The Viscosity Of Crude Oil With Microorganisms And Alleviating The H₂S Accumulation

There is a big comparison for dense oil in the oil resources of world, but there is a high viscosity, bad mobility for dense oil and it is difficult to recover dense oil. Microorganisms and its metabolism outcomes can lower the dense oil viscosity, make dense oil draw out from the well bottom easilier and help dense oil transportation. Therefore, it is very important to take on a research on lowering dense oil viscosity with the microorganism.Objective: To increase the dense oil recovery and transportation efficiency and clear oil well stops with microorganism. Methods: To get microbes that can lower dense oil viscosity effectively after proceeding function evaluation to the current microorganisms in our laboratory. Proceeding the research about the different carbon nitrogen source of seed educates, inoculating amount, inoculating time, pH, salty concentration turning an influence on oil biodegradation. Then proceed orthogonal experiment for confining composition and educating time of Zn, ZUO fermentation education and ratio experiments for bacteria and yeast and enhanced oil recovery experiments evaluating its result to increase oil recovery rate and research on repressing H2S creation. Result: Get the bacteria Z13, ZUO and the yeast J3, Jg with good effects on oil biodegradation. There is a good oil biodegradation for Zn, ZUO when carbon source of seed is liquid paraffin, rude oil and nitrogen source is NaNO3, NH4NO3. There is a good oil biodegradation effects with inoculation amount at 10% and 15%, educating 5 days before inoculation,educating temperature at 40C~50C, the density of NaCl less than10%,initial pH value beyond 7~8. When there are 40ml crude oil, 2.1g NaNO3, 2.1 g NH4NO3, 5.0g KH2PO4 in 1L liquid educate, educating 7 days for Z13 or 60ml crude oil, 0.7g NaNO3,0.7gNH4NO3,5.0g KH2PO4 in 1L liquid educate, educating 6 days for ZUO and bacteria compared with yeast at 4 II ,it is very good for oil biodegradati.The oil recovery rate of the mixture comes to 47.3%, SRB number variates from 1.6x109units/ml to 8.1x108units/ml and the H2S amount variates from 628.5 mg/l to 597.6 mg/l after joining the mixture. Conclusion: The microorganisms can decline dense oil viscosity effectively and have the ability to restrain H2S creation,we can increase their biodegradation function by change education condition,so they have a good applicable prospect at microbial enhanced oil recovery.