生物预处理促进褐煤制甲烷的内在原因分析

为提高褐煤制甲烷的产气量,利用放线菌Streptomyces viridosporus、真菌Phanerochaete chrysosporium和细菌Pseudomonas pseudoalcaligenes分别对褐煤进行预处理和生物甲烷产气实验。通过化学需氧量(COD)、三维荧光和XPS等测试探讨生物预处理提高煤制甲烷的内在机理。结果表明:S.viridosporus,P.chrysosporium和P.pseudoalcaligenes预处理煤的产气效果比原煤的产气效果分别提高了36.90%,165.39%和69.22%,液相的COD值升高,COD增幅分别为429.47%,596.94%和446.58%;液相中有机质主要以色氨酸类蛋白质、腐植酸和富里酸类腐殖质为主,同时煤表面芳香单元及其取代烷烃(C—C,C—H)的相对含量分别降低了8.56%,11.68%和6.74%,含氧有机碳(C—O,C=O,O—C=O)的总体相对含量分别增加了77.25%,105.31%和60.92%。生物预处理主要通过改变液相中的有机质含量和化学官能团来促进煤制甲烷。

Analysis on Underlying Mechanism of Biological Pretreatment Promoting Biological Methanation of Lignite

In order to improve the methane production from lignite,Streptomyces viridosporus(actinomycetes),Phanerochaete chrysosporium(fungi)and Pseudomonas pseudoalcaligenes(bacteria)were chosen for the pretreatment and the biomethane production experiments on the lignite.The COD,three-dimensional fluorescence and XPS tests were conducted to explore the underlying mechanism of the methanation of coal through the microbial pretreatment.The results show that the gas production of pretreated coal by S.viridosporus,P.chrysosporium and P.pseudoalcaligenes are 36.90%,165.39%and 69.22%higher than that of raw coal,respectirely,and the COD values in the liquid phase increase by 429.47%,596.94%and 446.58%,respectirely.After the pretreatment of different bacteria,the main organic matters in the liquid phase are tryptophan-like protein,humic acid and fulvic-like.At the same time,the relative contents of the aromatic units and substituted alkanes(C—C,C—H)on the coal surface decrease by 8.56%,11.68%and 6.74%,respectively,and their total relative contents of the oxygen-containing organic carbon(C—O,C=O,O—C=O)increase by 77.25%,105.31%and 60.92%,respectively.Hence,the microbial pretreatment of coal can promote the methane production efficiency of coal by changing the content of the organic matter in the liquid phase and chemical functional groups.