Study on monitoring and measuring method of positive pressure bundle tube for prediction and forecast of coal spontaneous combustion

According to the forecast and prediction of coal spontaneous combustion,due to environment air easily leaked into bundle tube existed in positive pressure bundle tube monitoring and measuring system,the monitored and measured gas density and contents could not actually reflect actual condition problem of monitored and m easured location. Based on positive pressure gas transportation method,the max transportation pressure would not be restricted by the vacuum and could be higher than th e environment pressure. During gas transportation process the environment gas could not enter into the bundle tube and would have other advantages. Positive pressure w as provided as detected gas transportation method and a positive bundle tube monitoring and measuring system was researched and developed. The positive pressure gas transportation experiment was conducted with different length bundle tubes. The experiment and theoretical calculation results showed that positive pressure transportation power was 4. 3 times higher than negative pressure transportation power. The application of positive pressure air transportation would not only reduce air transportation ti me,but could ensure gas density unchanged. The data measured by positive pressure bundle tube could actually reflect coal spontaneous combustion status.