Evolution of enzyme activity, heavy metals bioavailability and microbial community in different temperature stages of the co-bioevaporation process
Benqin Yang, Xukun Li, Zhiqiang Lin, Die Hu, Yanmei Liu, Xuejun Pan
Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China.
Laboratory investigations documented enzyme activity, heavy metals’ bioavailability and the bacterial community during co-bioevaporation treatment of food waste and landfill leachate. The activities of dehydrogenase, protease, urease and phosphatase were sensitive to the changes in operating temperature inherent in co-bioevaporation. The maximum dehydrogenase activity was appeared at warming 30°C. The maximum hydrolytic activity of the microorganisms on protein, urea and phosphorus-containing organic compounds appeared at warming 50°C. The bacteria mainly gathered on the surface and in the pores of the sludge particles used as a bulking agent. Bacterial abundance reached its maximum at warming 50°C. Firmicutes, Actinobacterica and Proteobacterica were the dominant bacterial phyla involved. Even though co-bioevaporation concentrated the heavy metals in the leachate, their bioavailability was substantially reduced during the process.
Keywords: Co-bioevaporation, Enzyme activity, Bacterial communities, Bioavailability, Heavy metals, Landfill leachate.