Culture Optimization and Performance Analysis of Oxygen-Consuming Bacterial Flora.

The regulation of oxygen concentration in underground coal mines is an efficient method to prevent coal spontaneous combustion. The screening and development of efficient oxygen-consuming microbial flora is a fundamental prerequisite for the application of biotechnology in preventing coal spontaneous combustion. For the initial screening, activated sludge obtained from Qinglong Coal Mine in China was utilized as an inoculum source to cultivate a group of Aerobic microbiota (AMS) with a relatively stable community structure. Afterward, the community structure of AMS was analyzed using 16SrRNA gene sequencing technology. Subsequently, single-factor experiments were conducted to optimize culture conditions (carbon source concentration, pH, inoculum amount) based on the growth characteristics of dominant strains. Finally, the oxygen consumption characteristics of AMS were investigated using a range of indicators, including oxygen consumption rate, CO₂ generation and growth concentration (OD) as measured by AMS. The results indicated that the growth activity of AMS was most robust when the carbon source concentration was 1%, pH was 7, and the inoculation amount was 10%, with an oxygen consumption rate of 94.83%. The experiment observed a significant increase in the concentration of CO₂, which rose from 0.096% to 30.272%. This gas is the primary product of AMS. Interestingly, growth was possible in environments with O₂ concentrations ranging from 5% to 29%, indicating that AMS is adaptable and can survive in environments with significant changes in O₂ concentrations. In addition, the combined effect of reducing O₂ concentration and inerting the mining zone made AMS more effective in suppressing spontaneous combustion of relict coal. [ABSTRACT FROM AUTHOR]