Investigation On The Behaviors And Reaction Kinetics Of Low Rank Coal Direct Hydro-liquefaction

The hydro-liquefaction experiments of Inner Mongolia lignite and Sinkiang Heishan coal were carried out within the temperature from390℃to450℃in lab. The main influence factors of Inner Mongolia lignite hydro-liquefaction reaction were investigated. At the same time, some kinetic models described the Inner Mongolia lignite and Sinkiang Heishan coal liquefaction processes were built up well.The effects of temperature, pressure, residence time and some other factors on Inner Mongolia lignite liquefaction reaction were investigated. The results showed that the temperature was a core factor. With the increase of temperature, the conversion and oil+gas yield were increased. When residence time was60min, the conversion and oil+gas yield of Inner Mongolia lignite were66.89%and43.65%within390℃, but when the temperature changed into450℃, the conversion and oil+gas yield were89.78%and65.31%. In the same condition, the conversion and yield of Oil and gas of Sinkiang Heishan coal were65.08%and34.01%at390℃and87.38%and58.49%at450℃, respectively. The yield of PAA was presented a trend of reducing after an increase. Initial hydrogen pressure took some effects and increased the reaction rate in the reaction. In addition, with increase of time, the conversion and oil+gas yield of two coals were increased, PAA was reduced after an increase.The multi-component kinetic model and piecewise kinetic model were compared, the multi-component kinetic model was a better one. In this model, the reaction constants k1of lignite conversing into oil and gas were between0.014-0.074min-1, the reaction rate constants k2of lignite conversing into PAA were between0.2-0.7min-1, and the reaction rate constants k3of PAA conversing into oil and gas were between0.00007-0.0043min-1. In the three reaction processes, the activation energy parametersEi was114.93KJ/mol, E2was74.75KJ/mol and E3was284.00KJ/mol, respectively. For Sinkiang Heishan coal, the three reaction rate constants k1,k2, k3were between0.007-0.031min-1,0.148-0.240min-1and0.0001-0.014min-1, respectively. Accordingly, the activation energy parametersE1, E2, E3were90.90KJ/mol,35.89KJ/mol and303.91KJ/mol, respectively. Moreover, the results of TG/DTG showed the reactivity of Inner Mongolia lignite was higher than the Sinkiang Heishan coal’s, and the hydro-liquefaction condition of Inner Mongolia lignite was milder than that of Sinkiang Heishan coal.