Experimental Study Of Rapid Coal Liquefaction Technology Under Hydrogen-rich Gas

With the sustainable and rapid development of national economy, oil security is being on the core position of Chinese energy strategy. Limited growth in petroleum supply and uneven petroleum market have being brought a significant gap between supply and demand of liquid fuel. Direct liquefaction of coal will become a viable option for the production of fuel with abundant low-rank coals in China. In order to reduce the cost, rapid liquefaction of Longkou lignite under methane atmosphere was studied in a novel tubular reactor system.First, under methane atmosphere the effects of reaction temperature and reaction time on the coal coversion and products distribution were studied. The experiments were performed at a temperature ranging from 400 to 800℃, a reaction time ranging from 4 to 12s, under pressure of 10MPa and no catalyst. Liquid products were fractionated into oils, asphaltenes and preasphaltenes using pentane, toluene and THF as extractive solvents. On the basis of these results, up to 25.44% of total conversion and up to 21.97% of oil-gas yield can be achieved at 9s and 750℃. The optimum temperature and reaction time was achieved. The results indicated that the liquefaction process is reasonable and rapid liquefaction is feasible.Under the standard temperature and reaction time, the effect of ratios of CH4/C2H4 on the coal coversion and products distribution were studied. Same as ever, liquid products were fractionated into oils, asphaltenes and preasphaltenes using pentane, toluene and THF as extractive solvents. Based on comparative the results, up to 29.45% of total conversion and up to 24.56% of oil-gas yield can be achieved at 9s and ethane content 15%. So, ethane is favor of rapid liquefaction.The analysis of raw coal and liquefaction residue is introduced in part three. In this study, raw coal and liquefaction residue were characterized by scanning electron microscope (SEM), Fourier transforma- tion infra-red microspectroscopy (FTIR), Temperature-Programmed Thermogravimetry instrument, X-Ray Diffractometer (XRD) and Elemental Analyzer. These results have provided a scientific basis for improvement of the novel technology.Part four consists of the conclusion and prospect. Writers give a summary of the whole paper, and, at the same time, present the problem and research direction of the novel technology.