Comparison between the Quick Start-up of EGSB and UASB

The quick start-up of the laboratory expended granular sludge bed(EGSB) reactor and the characteristics of the granular sludge during start-up were studied,and it was compared with the up-flow anaerobic sludge bed(UASB) reactor.The results showed that the whole start-up of the UASB reactor could be finished in 45 days,and the maximum COD_(Cr) loading rate was 5 kg/(m~3·d) and COD_(Cr) removal was about 80%.On the other hand start-up of the EGSB reactor could be finished in 25 days,the COD_(Cr) loading rate was be 8 kg/(m~3·d) and COD_(Cr) removal was larger than 90%.EGSB is better than UASB in the start-up.During start-up of the EGSB,the characteristics of granular sludge change greatly: the average granular diameter increases from 0.88mm to 1.25mm;methanegenic activities of the granular increases up to 4 times large as the seeded sludge.