Formation of extracellular polymeric substances from acidogenic sludge in H2-producing process.
In this study, the formation of extracellular polymeric substances (EPS) and surface characteristics of an acidogenic sludge in anaerobic H(2)-producing process was investigated. Results show that carbohydrates, proteins, and humic substances were the dominant components in bound EPS (BEPS), while in soluble EPS (SEPS), carbohydrates were the main component. The total content of BEPS initially increased but then kept almost unchanged during fermentation from 25 to 35 h; after that, it slightly decreased. The total content of SEPS increased to 172.5 +/- 0.05 mg C g(-1) volatile suspended solid with the time that increased to 23.5 h, and then rapidly decreased until 43 h; thereafter, it kept almost unchanged. The SEPS had good correlations with the specific H(2) production rate, substrate degradation rate, and specific aqueous products formation rate, but the BEPS seemed to have no such correlations with these specific rates. Results also confirm that part of EPS could be utilized by the H(2)-producing sludge. As the substrate was in short supply, the EPS would be hydrolyzed to sever as carbon and energy source.
Sheng
Guo-Ping
GP
School of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
Yu
Han-Qing
HQ
D000693:Anaerobiosis; D001704:Biopolymers / Q000302:isolation & purification / Q000378:metabolism*; D001709:Biotechnology / Q000379:methods; D050260:Carbohydrate Metabolism; D006812:Humic Substances; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D011506:Proteins / Q000378:metabolism; D012722:Sewage / Q000382:microbiology*; D014865:Waste Disposal, Fluid / Q000379:methods*
D001704:Biopolymers; D006812:Humic Substances; D011506:Proteins; D012722:Sewage; D006859:Hydrogen