煤矿乏风的预热催化氧化试验研究

山东理工大学硕士学位论文AbstractAbstractMore than twenty billion cubic meters of methane is discharged each yeah in China,80 percent of the coal mine methane is of ultra-low concentration,which has the quality ofhuge volume,low concentration and it fluctuate strongly in amount and concentration.Somost of methane is discharged without any treatment,as a result,environment pollutionand energy waste is increasingly serious.So it is of vital importance to study newtechnology dealing with ultra-low concentration methane.The characteristic of a late-model preheat catalytic oxidation device wasexperimentally studied in this paper.Before that,some improvements and new design weredone to keep the device self-running.Then lots of experiments were done to study theperformance of the device,the contents are as follows:(1)The study of starting performance shows that,with the increase of flow rate,theheating rate decrease,and the temperature of oxidation bed is more even;with the increaseof heating power,the heating rate increase,and the evenness of temperature in oxidationbed is worse;the best coefficient of flow rate is between 0.3 and 0.4,the lowest startingpower is 0.03kW/m3,and the optimum starting power is 1.3-1.6 times of the lowest startingpower.(2)The study of oxidizing performance shows that,with the increase of flow rate,thetemperature in oxidation bed and the conversion rate of methane increase slowly thendecreases rapidly,the efficiency of energy recovering decreases rapidly,and thetemperature of exhaust gas increases slightly;with the increases of concentration ofmethane,the temperature in oxidation bed and the conversion rate of methane increase,theefficiency of energy recovering increases,and the temperature of exhaust gas increasesslightly;with the increase of temperature of oxidation bed entrance,the temperature inoxidation bed and the conversion rate of methane increase,the efficiency of energyrecovering increases,and the temperature of exhaust gas increases to some extent.(3)The study of resistance characteristics shows that,resistance loss in each partincreases with the increase of flow rate,but the pattern are different:the resistance loss inpreheater increase quadratic,the resistance loss in oxidation bed increase linearly;resistance loss in each part increases with the increase of temperature in oxidation bed,but