Anaerobic digestion of solid residue of water hyacinth.

To investigate the influences of solid-liquid separation on anaerobic digestion of water hyacinth,a set of experiments in both lab scale and pilot scale were conducted on solid residue from squeezing water hyacinth by batch test.The results showed that,under mesophilic condition(35 ℃)with total solids(TS) of 8%,the water hyacinth residue could produce biogas of 398 ml/g(TS),in which methane content reached 59%.The results of anaerobic fermentation at pilot scale revealed that water hyacinth residue had biogas yield of 0.33 m3/kg(TS),the highest volume biogas yield of 0.60 m3/(m3·d),and the average volume biogas yield of 0.27 m3/(m3·d),at normal temperature(21-29 ℃) by leachate recycling.The results demonstrated that the water hyacinth residue squeezed from water hyacinth,was efficient for biogas production.