Isolation And Application Research Of Acidophilic Heterotrophic Bacteria Isolated From Stone Coal Drainage

Different mine water have different types of microorganisms. This paper mainlyconducted a study on the enrichment, separation and identification of acidophilicheterotrophic bacreria, and also studyed on its ore leaching ability. The main contentsand conclusions are as follows:(1) The isolation of acidophilic heterotrophic bacteria from acid main drainagefrom stone coal in Yiyang, Hunan province. Two strains of acidophilic heterotrophicbacteria named YY-1and YY-2were successfully isolated from acid drainage waterusing BSYG selective media.(2) The physical and chemical properties of YY-1and YY-2. Using single factorexperimental analysis methods, determined the optimal growth temperature of YY-1was30℃and the optimal initial pH value was3.0; the optimal growth temperature ofYY-2was25℃and the optimal initial pH value was3.5; YY-2was halophyticbacteria, its optimal salt concentration was7.5%, the maximum salt concentration was18%. YY-1and YY-2could use sucrose, fructose, lactose, maltose, glucose, cerealose,glycerin, sodium citrate and glusate as energy for growth, YY-2was capable of usingsodium acetate and acetic acid, but YY-1can not use acetate and acetic acid. Both ofthem can participate in the iron cycle, but can not involve in sulfur metabolism,sodium thiosulphat will inhibit bacterial utilization of glucose.(3) Morphological characteristics and biological satus of YY-1and YY-2. Thegram-negative-straining cells of YY-1were straight long rod,(0.4～0.7) μm in lengthand (0.9～1.6) μm in diameter; The gram-negative-staining cells of YY-2were oliveshape,(1.2～2.4) μm in length and (2.3～8.8) μm in diameter. YY-1had a highsequence similarity with Acidiphilium cryptum JF-5, with over99%; YY-2had a highsequence similarity with Acidiphilium multivorum AIU301, with over99%; there wasalso a high degree homology between the two strains.(4) Bacteria leaching ability. Using raw coal and9K basic salt solution simulatedthe bioleaching system. The experiments results showed that all of the bacteria couldpromote metal leaching of vanadium in stone coal. After40days of leachingexperiments, vanadium extraction rate of YY-1was42.1%; vanadium extraction rateof YY-2was37.6%; vanadium extraction rate of autotrophic lead leaching bacteriaATC230was40.1%. All combinations of mixed bacteria had a better vanadium extraction rate than single bacterium. The mixed bacteria (YY-1and ATC230) had ahighest effect, with over48.1%vanadium extraction rate; the mixed bacteria (YY-2and ATC230) had a vanadium extraction rate over46%; the mixed bacteria (YY-1,YY-2and ATC230) had a vanadium extraction rate over44.8%.(5) Study on the interactions between bioleaching microbes. The experimentalresults showed that both YY-1and YY-2can accelerate the growth and bioleachingactivity of ATC230, YY-1had a better acceleration, and the mixed bacteria (YY-1andYY-2) had a strong role in promoting.