Research On Pyrolysis Characteristics And Residue Utilization Of Jimusar Oil Shale

Oil shale is one of the important unconventional energy. During pyrolysis of oil shale, shale oil could be obtained with hydrocarbon ratio similar to crude oil, and it has the important strategic significance to make up the deficiency of oil energy resource. It is the foundation of oil shale optimize conversion that the pyrolysis characteristics has been studied.The main purpose of this paper was to research the pyrolysis behavior of Jimusar oil shale. The effects of pyrolysis temperature, particle grain size and retention time on products yield and composition during pyrolysis were investigated. Kinetics characteristics of Jimusar oil shale during pyrolysis was investigated by TG. At last, The feasibility of preparation of zeolite from oil shale ash was discussed. The main research works and results are as follows:The effects of pyrolysis temperature, particle grain size and retention time on the pyrolysis process of oil shale under N2 atmosphere were investigated in a fixed-bed reactor. The produced residue was characterized using BET and FT-IR, and character of oil and gas were measured by GC-MS and GC analysis. The results shown that increasing the temperature, The water yield and gas yield have an increase trend. Oil yield increase with increasing temperature, but decrease after temperature above 530℃. Decreasing the particle grain size, Oil yield has a decrease trend, gas yield has an increase trend, while water yield has no change. Oil yield increase with increasing retention time, but decrease after retention time above 30 min. It was found that the optimum conditions for Jimusar oil shale pyrolysis were: under nitrogen atmosphere, heating rate 10℃/min, temperature 530℃, particle grain size 0.42~0.84 mm, retention time 30 min.The characteristics of Jimusar oil shale pyrolysis was investigated by TG, Two thermoanalytical method(the Coats-Redfern method and Freeman-Carroll method) are adopted to calculate the apparent activation energy and Arrhenius constant. In kinetic calculations, the best reaction order with linear correlation coefficient has been confirmed by thermogravimetric fit linear. The results shown that the apparent activation energy has a great change during the pyrolysis process. Increasing the heating rate, the apparent activation energy has a decrease trend. The apparent activation energy calculated by Freeman-Carroll method is larger than that by Coats-Redfern method. When the heating rate is low, the apparent activation calculated by Coats-Redfern method is more accurate, when the heating rate is tall, the apparent activation energy calculated by Freeman-Carroll method is more accurate.The hydrothermal synthesis method was studied to converse of oil shale ash into zeolite. The effects of synthesis temperature and synthesis time on the process of synthesis of zeolite were discussed. The physical and chemistry characteristics of synthesis zeolite were obtained by XRD, SEM, and BET method. It was found that the optimum conditions for zeolite synthesis process were: baking temperature 800℃, the dosage ratio of Na OH and oil shale ash was 1:1, synthesis temperature120℃, synthesis time 12 h.The adsorption characteristics of Cu2+ from simulated wastewater by oil shale ash and zeolite were studied, and the effects of adsorbent dosage and adsorption time. The results shown that the dosage of oil shale ash was 40g/L, adsorption time was 100 min, the removal efficiency of Cu2+ was 76.5%, while the dosage of synthesis zeolite was 20g/L, adsorption time was 80 min, the removal efficiency of Cu2+ was 92.6%.