Abstract
The paper reports on the biogas production from water hyacinth (Eichhornia crassipes) and channel grass (Vallisneria spiralis)
employed separately for phytoremediation of lignin and metal-rich pulp and paper mill and highly acidic distillery effluents. These
plants eventually grow well in diluted effluent up to 40% (i.e., 2.5-times dilution with deionized water) and often take up metals and
toxic materials from wastewater for their metabolic use. Slurry of the two plants used for phytoremediation produced significantly
more biogas than that produced by the plants grown in deionized water; the effect being more marked with plants used for phytoremediation
of 20% pulp and paper mill effluent. Biogas production from channel grass was relatively greater and quicker
(maximum in 6–9 days) than that from water hyacinth (in 9–12 days). Such variation in biogas production by the two macrophytes
has been correlated with the changes in C, N and C/N ratio of their slurry brought by phytoremediation.
2002 Elsevier Science Ltd. All rights reserved.