关键词: 铬革屑, 耐铬菌, 厌氧发酵, 胶原蛋白

Abstract: A chromium-resistant dominant fungus FN was separated, purified, and screened from the chromium-containing sludge in a tannery. Through the gradient experiments, it was determined that the dominant bacteria had a chromium-resistant concentration of 1000 mg/L for chromium-containing collagen, and the anaerobic acclimation of the strain was successfully carried out. The fungus FN was finally identified as Aspergillus oryzae. FN was then used in the anaerobic digestion of chromium-containing collagen, and the anaerobic digestion and gas production properties were investigated. The experimental results show that the inoculation amount of chromium-resistant bacteria is 25%; the initial pH is about 7; the temperature is 35 ℃, and the vibrating speed is 110 r/min. When the carbon/nitrogen (C/N) ratio is 25, the gas production performance of the anaerobic digestion system is the best. Next day, the highest daily gas production reached 295 mL. The cumulative gas production in 30 days was 1292.5 mL; the methane content was 52.57%; the chromium removal rate was 31.02%, and the protein hydrolysis rate was 65.2%. The C/N ratio is 35; the initial pH is about 7; the temperature is 35 ℃, and the chromium-resistant bacteria dosage is 50% under the vibrating conditions of 110 r/min. The gas production performance of the anaerobic digestion system is the best, and the highest daily output is reached the next day. The gas volume is 414 mL; the cumulative gas production in 30 days is 1648 mL; the methane content is 45.18%; the chromium removal rate is 41.96%, and the protein hydrolysis rate is 86.49%.

Key words: chrome shavings, chromium-resistant bacteria, anaerobic fermentation, collagen