Study On Microbial Degradation Of Methane Andits Intermediate Product Formaldehyde

Coal mine gas is a mixture of gases,which are usually toxic and harmful.And these gases are poured out in coal seams in the process of coal mining.The mine gas is the main reason for the safety production of the coal mine in China.Recent years,With the increasing depth of mining in the mine,the excavation stress is greatly improved,the gas concentration of coal seam is increasing rapidly,while the permeability coefficient is getting lower and lower,the traditional means of gas control show certain limitations.Under this situation,More and more experts pay attention to and carry out the exploration and research work on the theory and technology of coal mine gas control by microorganism.The purpose of this study is to isolate and purify methane oxidizing bacteria which can efficiently degrade methane,and to study the production of formaldehyde in the process of methane degradation.During the experiment,it was found that strain 2 had higher ability to degrade methane,and the physiological characteristics of the strain were in accordance with the physiological characteristics of methane oxidizing bacteria reported in the current literature,methane oxidizing bacteria are determined by the test of methane degradation.Methane oxidizing bacteria growth environment were optimized by single factor method,and using the spectrophotometer to measure the bacterial fluid OD value,found that on the 7d the OD value was maximum,that was the number of live bacteria was largest in bacterial liquid.;The formaldehyde generated during the degradation process was detected by acetyl acetone method,and optimized the detection method,during the 14 d that the growth cycle of a methane oxidizing bacteria,on the 7d the formation of formaldehyde is the most.;Changing the methane concentration in the culture bottle,found that when the methane concentration is higher than 60% or lower than 20%,the physiological activity of methane oxidizing bacteria and the formation of formaldehyde are not affected by methane concentration,when the methane concentration in the culture bottle at 20%~40%,the metabolic activity of methane oxidizing bacteria and the formation of formaldehyde were increased with the increasing of methane concentration.;Changing the oxygen concentration in the culture bottle,found that when the oxygen concentration above 40%,the formaldehyde production is not affected by the oxygen concentration.When the oxygen concentration is below 40%,the higher the oxygen concentration is,the greater the formaldehyde production is.