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This article uses experimental methods to measure the operational performance and pollutant emissions of micro gas turbines in different intake environments, and analyzes the feasibility of replacing mine ventilation fans with micro gas turbines. The results show that when the compressor efficiency is increased from 70 % to 90 %, the total efficiency of the micro combustion engine is increased from 28% to 34 %, with an increase of up to 21.4 %. When the demand power is 25 kW, the fluctuation range of NOx emission concentration is within 5.4 %. When the intake opening is below 50 %, the effect is obvious. When the intake opening is reduced from 50 % to 25 %, the performance of the micro gas turbine decreases by 0.7 %; The influence of intake humidity on various operating parameters of micro gas turbines is generally within 3 %, which can meet the requirements of high humidity environment operation; The intake temperature has the greatest impact, with an increase in intake temperature leading to a decrease in power generation efficiency. After comprehensive analysis, we believe that the application of gas turbines in mines is feasible.

For problems of wired while drilling device (MWD) which used central cable drilling rig as signal transmission channel such as complex drilling rig structure, limited mechanical behavior, poor anti-interference performance and so on, a mine-used mud pulse wireless MWD device was developed. The device is composed of explosion-proof computer, explosion-proof keyboard, explosion-proof data memory, explosion-proof measuring tube, explosion-proof pressure transmitter, etc. It works in intermittent mode. When shutdown signal of mud pump is detected by measuring section of the explosion-proof measuring tube, static data including drilling trajectory parameter and state parameter of directional drilling tool is collected and coded. When opening signal of mud pump is detected, following works are done by driving section of the explosion-proof measuring tube including sending the static data, measuring and sending dynamic data, and controlling the pulse generator to adjust flow channel area of hydraulic conduit. The explosion-proof pressure transmitter collects pressure signal of mud pump and sends it to the explosion-proof computer. When data transmission is completed, the explosion-proof measuring tube stops working, flow channel inside the pulse generator is restored, mud pump pressure is changed to normal value, then directional drilling is started. The test result shows that the device runs stably with correct measurement data and improves efficiency and safety of directional drilling, which can meet directional drilling need of all kinds of coal-seam or rock-seam drilling holes and realize measurement while drilling of traditional drilling trajectory.

In order to solve problems of short usage time, poor signal stability, high fault ratio and high maintenance cost of existing cable measurement while drilling device for coal mine drilling which was powered by battery in hole, a technology scheme was proposed which used explosion-proof computer to power supply measuring tube in hole. By researching design of constant voltage source and signal demodulation of explosion-proof computer, design of parameter measurement, secondary power supply and signal carrier transmission work of measuring tube and development of measurement software, a cable measurement while drilling device was developed which was powered by explosion-proof computer. Measurement accuracy test of the device is taken in a professional organizations as well as work stability test in Shizuishan No.2 Coal Mine and depth test in Sihe Coal Mine. The tests results show that the device is feasible with higher measuring accuracy than the design value, and has strong working stability with drilling transmission distance of 1 881 m. The device can meet need of directional drilling with different types in coal mine.