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In order to solve the problems of low surface energy, long microbial attachment time and slow start of membrane hanging in the process of enhanced water purification, an iron carbon fiber-CF artificial water mat was constructed by combining waste iron and carbon fiber water mat. The heavily polluted surface water was used as raw water. Under the condition of stage aeration, the experiment of enhanced membrane hanging was carried out. The results showed that compared with carbon fiber artificial aquatic mat, the adhesion performance of biofilm on iron carbon fiber artificial aquatic mat was significantly improved, the hanging rate of biofilm increased from 125.1% to 133.0%, and the size of biofilm cluster structure was significantly larger. The polysaccharide, protein and protein-to-polysaccharide ratio in the extracellular polymer of biofilm changed from 53,11 mg/gVSS and 1.33 to 39, 106 mg/gVSS and 2.71 at the end of the initiation period (21 d), respectively. The enrichment and screening of Pseudomonas bacteria by iron-carbon materials improved the movement ability of bacteria and promoted the secretion of extracellular polymers by bacteria. In addition' the highly expressed functional genes of microorganisms were highly expressed in ICF, which improved the adhesion performance of microorganisms on the surface of iron-carbon fiber materials. [ABSTRACT FROM AUTHOR]

In order to study the role of microbial community in lignite biogas production process and the change of coal sample properties before and after gas production, the lignite obtained from Shengli in Inner Mongolia was used as the substrate for gas production, and the enriched anaerobic flora in Sihe mining area was used as the starting bacterial community. In the laboratory scale, the lignite biogas production was conducted. The microbial community changes before and after gas production were analyzed by Illumina high-throughput sequencing platform. Gas chromatography, scanning electron microscopy, etc. were used to analyze the methane production of lignite and the physicochemical properties of coal samples before and after gas production and the morphology of the coal surface. The results showed that Inner Mongolia Shengli lignite could be utilized by the enriched flora and produce methane with a biogas production cycle of 49 days, and the cumulative methane production was 83. 1 mL. The net methane production rate was 7-84 mL/g coal. The diversity of bacterial communities in the biomass biogenic samples of lignite was abundant. The main dominant bacteria at phylum level were Firmicutes, Proteobacteria, WWE1, Bacteroidetes, Synergistetes and Deferribacteres. The initial microbial flora had high diversity, however, the microbial diversity decreased after the biogas generation with lignite and basic medium. The microbial structure changed obviously at genus level, and the dominant bacteria W22, Proteiniclasticum, VadinCA02, Tissierella soehngenia, Clostridium and Desulfovibrio played important roles in the biogas generation. Inner Mongolia Shengli lignite had higher volatile matter, rich in hydrogen and oxygen, and the surface structure of coal was loose, with obvious cracks, which was beneficial to microbial adhesion and degradation, and was suitable for biogas production. After the biogas production, lignite’s volatile content, water and ash, the proportion of S and O elements decreased, however the percentage of fixed carbon and the H/C increased. The SEM results showed that a large number of short rod-like and spherical microbes absorbed onto the surface of coal, and also had similar microorganism nanowire structure. [ABSTRACT FROM AUTHOR]