Investigation on the Effect of Atmosphere on the Pyrolysis Behavior and Oil Quality of Jimusar Oil Shale. (2nd March 2022)

• Record Type: Journal Article
• Authors: Kang, Zhiqin; Wang, Zhijing; Lu, Yang; Cao, Ran; Huang, Dongwei; Meng, Qiaorong
• Other Names: Zhao Yu Academic Editor.
• Is Part Of: Geofluids. Volume 2022(2022)
• Publication Date: 2022-03-02
• Subjects: Hydrogeology -- Periodicals; Sedimentary basins -- Periodicals; Fluids -- Migration -- Periodicals; Groundwater flow -- Periodicals; Geothermal resources -- Periodicals; Fluid dynamics -- Periodicals; Earth -- Crust -- Periodicals; 551.49
• DOI: 10.1155/2022/1408690
• Languages: English
• ISSNs: 1468-8115

Abstract

Abstract : High-temperature H2 O and CO2 can improve the pyrolysis behavior of oil shale. Therefore, in this paper, Jimusar oil shale was selected as the research object and the effect of the reaction atmosphere (H2 O, CO2, and N2 ) on its pyrolysis behavior, pyrolysate distribution, and pyrolysis oil quality was fully compared and studied. The results showed that compared with the N2 atmosphere, the presence of H2 O and CO2 both increased the weight loss and weight loss rate during pyrolysis of oil shale and the existence of H2 O advanced the initial precipitation temperature of volatiles by 17°C. The comprehensive release characteristic indices of volatiles during pyrolysis of oil shale in the CO2 and H2 O atmospheres increased by 49.34% and 114.35%, respectively, which significantly improved its pyrolysis reactivity. Both H2 O and CO2 atmospheres improved the pyrolysis oil yield of oil shale, and the pyrolysis oil yield in the H2 O atmosphere performed better than that in the CO2 atmosphere. Especially, the H2 O atmosphere could increase the pyrolysis oil yield by 41.42%. The existence of CO2 prevented methyl radicals from accepting hydrogen radicals during pyrolysis and reduced the alkane yield, while CO2 participated in the addition reaction of alkane, which increased the alkene yield. High-temperature H2 O provided more hydrogen source, which increased the alkane yield and inhibited the alkene formation. Both H2 O and CO2 atmospheres promoted the cracking of polycyclic aromatics and increased the yield of small-molecular aromatics in the pyrolysis oil. During the pyrolysis process of oil shale, CO2 and H2 O underwent reforming reaction with the heavy oil, which increased the light component fraction, thereby increasing the H/C ratio of pyrolysis oil. Thus, the existence of H2 O and CO2 atmospheres improved the quality of pyrolysis oil and the effect of H2 O was better than CO2 . The H2 O and CO2 atmosphere promoted the formation of a well-developed pore structure, which was conducive to mass and heat transfer during pyrolysis of oil shale.