Thermochemical liquefaction of water hyacinth

Abstract

The use of non-edible biomass should be investigated as alternatives for biofuel production. Aquatic weeds like water hyacinth (WH) are classified as third generation crops. WH in South Africa is an invasive species that brings forth many problems in the utilization of water resources. Liquefaction experiments were conducted on WH across a temperature range of 240 - 340ºC, at three different atmospheres. The maximum bio-char yield for the stem and leaves was found to be 54 ± 3.43wt% at temperature of 260ºC, and for the roots a maximum yield was obtained of 45.83± 3.2wt% at a temperature of 280ºC. Carbon monoxide was found to be the optimum atmosphere in liquefaction experiments of the roots, reaching on average a higher yield percentage of 4%. Due to low biomass loading in this investigation the production of bio-oil was found to be negligible. This investigation showed that it might be possible to use WH as feedstock for the production of renewable energy through thermochemical liquefaction. The calorific value (CV) was 10.887±0.451 MJ/kg and 23.306±0.451 MJ/kg for the roots and stem and leaves respectively. The high CV of the stem and leaves suggests that the possibility should be investigated for industrial application of the bio-char