Study on the Influence of L-AD (Liquid Anaerobic Digestion) and SS-AD (Solid-State Anaerobic Digestion) Methods to Biogas Production from Water Hyacinth (Eichhornia crassipes)

Anaerobic digestion is biochemistry process without oxygen that decompose organic complex compounds by various anaerobic bacterium and produce biogas. One of plant which contain the organic complex compounds that can be use as raw material for biogas is water hyacinth. Anaerobic digestion classified with two methods based on the total solid (TS) which liquid anaerobic digestion (L-AD) for total solid <15% and solid-state anaerobic digestion (SS-AD) for total solid >15%. Purpose of this research is determine the best methods to produce biogas from water hyacinth. Variation that used in this research is total solid from the water hyacinth. For SS-AD using TS 24.13% and 17.67%. For L-AD using 6.76% and 3.38%. The measurement for biogas production is using Boyle Law which using the difference of water level caused by the pressure of the gas. The result show that both methods give a real effect on biogas production from water hyacinth. Variable using SS-AD method produced less biogas than using L-AD method. The highest biogas yield produced by water hyacinth with TS 3.38% in the amount of 369 ml/grTS.