Selection of De-emulsification Strains and Optimization of Fermentation Conditions
- VernacularTitle:生物破乳菌的筛选及发酵条件的优化
- Author:
Xu LI
;
Ji-Xian YANG
;
Fang MA
;
Ning HOU
;
Yang XU
;
- Publication Type:Journal Article
- Keywords:
Biological de-emulsifier,De-emulsifying strain,Emulsion,Culturing conditions
- From:
Microbiology
1992;0(04):-
- CountryChina
- Language:Chinese
-
Abstract:
Petroleum-field emulsions,which are produced in the process of exploration,production and re-covery,represent a major environmental and processing problem for the petroleum industry.Biological de-mulsifier as a biological agent,will become a novel method of petroleum-field emulsions demulsifier instead of chemical demulsifier for its high efficiency,low cost,high adoptability,environment-friendly,repeated use.A set of high efficiency and convenient method was established to isolate de-emulsification strain and studied on the fermentation conditions of the de-emulsification strains.A de-emulsification strains,isolated from a petroleum-contaminated site,was evaluated for its de-emulsification capabilities using a kero-sene/water model emulsion system keeping stable for more than 200 hours which was mixed by stirring Tween 60-water(0.072%,V/V)and Span 60-oil(0.028%,V/V)at the ratio(oil:water)of 6.5:3.5.We have isolated two strains with high and steady de-emulsification activity by separation and purification,blood-plate test,excluding-oil test and de-emulsifying test.The average de-emulsification rates were more than 80.0% at 24 h.The two strains are both belonging to bacillus by traditional and molecular genetic iden-tification.By optimizing the demulsification bacteria fermentation conditions,the fermentation conditions,which is the most suitable for accumulating the fermentation products,were determined as follows:tem-perature 25?C,stirring speed160 r/min,pH 9,inoculated quantities 20%.When the fermentation conditions were temperature 35?C,stirring speed120 r/min,pH 9,inoculated quantities 2%,the fermentation products appeared the highest activities of demulsification.
