Biodegradable Plastic Production by Activated Sludge with Different Carbon Souces
外加碳源的活性污泥合成生物降解塑料PHAs的试验

Polyhydroxyalkanoates(PHAs) are polyesters synthesized by numerous bacteria in sludge as intracellular carbon and energy storage compounds under the condition of unbalance growth. Another important aspect of PHAs is thermoplastic polyester with the remarkable characteristics of biodegradability. In this paper, using sodium acetate, sodium propionate and sodium butyrate as the unique carbon source, 5.58%, 3.90% and 4.98% PHAs of dry sludge weight were obtained by assimilated sludge as PHAs synthesis strains in the anaerobic condition, and 12.32%, 9.55% and 11.35% PHAs of dry sludge weight were obtained in the anaerobic condition. It was shown that there were large quantities strains which could accumulate PHAs as granules in the cytoplasm of cells, and the yield of PHAs in the anaerobic process were higher than that in the aerobic process. The best result was that 12.32% PHAs of dry sludge weight was obtained in the best experiment condition, and the yield of the PHAs to substrate was 30.65%. The structures of PHAs were analyzed by 1HNMR spectrum, and the relationship of the structure of PHAs and the carbon source was explained.