In order to make better utilization of coal tailings (low quality production after coal preparation) as the resources, the pyrolysis characteristics and product distributions during co-pyrolysis of coal tailings together with biomass at different ratio (20%, 40%, 60% and 80%) were determined in thermogravimetric analysis (TGA) and a fixed bed reactor in this paper. Coal tailings (TC) selected was provided by Hexi coal in Shanxi province, and pine branch wastes (PBW) were used as biomass samples. The result of TGA experiments indicates that the temperature corresponding to the maximum pyrolysis rate exhibited a significant difference between TC and PBW, and the value of the calculated TGA and DTG curves is similar to the experimental ones. In a fixed bed experiments within a temperature range of 25-900°C, gas product yields of co-pyrolysis of TC and PBW are higher than those of the sum of them individually, while tar and char yields were on the contrary. It shows some synergetic effect exists during co-pyrolysis process of TC and PBW blends, and the maximum synergy exhibits with a PBW blending ratio of 40%. CO yield increases up to 30% at 400°C and CH4yield increases up to 11.33% at 700°C compared with the calculated value. These findings can potentially help to understand and predict the behavior of coal tailings/biomass blends in practical systems.

To investigate the effects of gangue on pyrolysis of municipal solid waste (MSW), pyrolysis of MSW with gangue has been conducted by TG and fixed-bed reactor, respectively. The effect of gangue on pyrolysis product yields and compositions of gaseous products was investigated and the obtained results were compared with similar experiments without gangue. It was shown that gangue can improve the pyrolytic reaction of MSW, reduce the char yield, increase the liquid yield. And influences of gangue on yields of H2, CO, CH4 and CO2 were more apparent, the yields of H2, CO and CO2 with gangue were improved 12.5%, 11.8% and 175%, respectively, conversely, the yield of CH4 was reduced 15.4% compared with no gangue.

The aims of this work were to investigate the influence of feedstock properties of different part of cassava residues (cassava rhizome (CR), cassava stalk (CS) and cassava leaf (CL)) and operating temperatures on the pyrolysis characteristics and the kinetic parameters. Pyrolysis experiments of three selected biomass feedstock were conducted using a fixed-bed reactor. It was shown that the bio-oil yield of cassava stalk reached the maxima at 600°C, and the char yield reduced with the temperature, whereas the gas yield increased with temperature. The cassava rhizome presented higher thermochemical reactivity than the other samples. The activation energy of cassava stalks was 37.57 kJ / mol and that of cassava rhizome (39.42 kJ / mol) increased slightly. The activation energy of cassava leaf (22.85 kJ / mol) was lowest of the three samples.

An experimental study on co-pyrolysis of municipal solid waste and corn stalk was performed in a fixed-bed reactor under atmospheric pressure. The effect of different blending ratio on the pyrolysis product yields and compositions of the gaseous products was investigated. The results indicated that there exist synergetic effects in the co-pyrolysis of municipal solid waste and corn stalk. Under the different blending ratio conditions, the char and liquid yields were lower than the theoretical values calculated on pyrolysis of each individual municipal solid waste and corn stalk, and consequently the gas yields were higher. H2 and CH4 obtained co-pyrolysis at 800°C-900°C of 40% blending ratio conditions were higher than those of municipal solid waste and corn stalk alone.

In gas-rich mines, gas problems exist in the process of mining, which not only increases the difficulty of mining coal resources, but also reduces the production of coal mines safety. Typically, gas explosion was one of the most serious disasters in coal mines, which caused large numbers of casualties and destruction of facilities. In order to prevent the gas accident during the mining process in the coal seam of Tashan Mine (which located in Datong, Shanxi Province, China), the No.3~5 coal seam were taken as an example, the gas drainage pumps and the pipe laying methods were designed, basing on its hydrogeological conditions, development methods and coal mining methods. The gas drainage pump with a flow rate of 309.95 m3/min was designed, which helps to make better use of existing mine gas resources better and more efficiently. In addition, integrated control technologies such as gas drainage, gas concentration monitoring, effective ventilation and control of fire sources were used to reduce the probability of gas explosion in the No.3~5 coal seam of Tashan Mine. Strengthen the prevention and control of gas disasters, so as to ensure the smooth progress of coal mine safety production. The gas drainage system has built with this design, which runs for several months, and achieved a good performance. Therefore, the design approach can be referred to other similar mines.