Use of Water Hyacinth (Eichhornia crassipes) to Treat Biogas Effluent of A Tapioca Industry Wastewater Treatment System

Abstract

This research aims to evaluate performance of a water hyacinth (Eichornia crassipes (Mart) Solms) pond used to treat biogas effluent of a tapioca industry wastewater treatment system.  The water hyacinth pond which treats biogas effluent has been monitored for about two months.  Wastewater samples were taken from influent and effluent of the water hyacinth pond.  Parameters to be observed included wastewater quality parameters (pH, temperature, turbidity, BOD5, ammonia, solids, evapotranspiration, discharge, and hydraulic retention time) and water hyacinth parameters (growth, population density, moisture, ash, nutrient contents).  The results showed that water hyacinth improved some parameters of the biogas effluent to some extent.  Within HRT of 53 days, pH increased from 7.0 to 7.2 and some reductions of turbidity by 27.1%, BOD5 by 3.2%, ammonia by 10.5%, TS by 13.1%, TFS by 11.4%, TSS by 35.2%.  With water hyacinth population of 10,17 kg/m², evapotranspiration was 5.48 mm/d.  The water hyacinth grew from 415 g.m^-2 to 3375 g/m² within 41 days, meaning that daily increase rate of 72.2 g/d and relative growth rate of 5%/d. The doubling time of water hyacinth was 13.56 days. Annual nutrient uptake for carbon (C), nitrogen (N), phosphor (P), and potassium (K) by water hyacinth was found to be 7800, 699, 701, and 333 kg/ha, respectively.