Effect of a termal pre-treatment and the temperature range on anaerobic digestion of water hyacinth (Eichornia Crassipes)

Abstract

Water Hyacinth (WH -Eichornia Crassipes) causes environmental problems in tropical areas, such as water eutrophication. A possible solution is to collect the plant and to use it for biogas production, trying to valorise the waste heat from the CHP unit, which is a limitation in tropical areas. The aim of the present work was to study the effect of a thermal pre-treatment at 80ºC on biodegradability of WH and to contrast the anaerobic process in mesophilic and thermophilic temperatures. Biodegradability tests were performed at 35ºC and 55ºC with thermal pre-treated and no pre-treated substrates. It is concluded that thermal pre-treatment at 80ºC do not enhance anaerobic digestion of WH, and total methane yields are similar for mesophilic (188.72 L CH4/kg VS) and thermophilic (191.04 L CH4/kg VS) assays, indicating no differences in final biodegradability. Nevertheless, the rates of methane production were higher for thermophilic assays