Food waste degradation and hydrolysis in a conventional leach bed reactor

Abstract

This experiment investigates how a conventional leach bed reactor performs when there are no modifications to its parameters. At an inoculum to substrate ratio of 4%, the effects on hydrolysis and production of VFAs were studied using mainly fruits and vegetables as the food waste. Hydrolysis rates were the highest on day 1 where pH levels were at 6.8. As the pH level of the reactor stabilized around 3.5, hydrolysis rates were noted to generally decrease as well. While the reactor was seen to reach 95% of total sCOD produced by day 6, which is considered relatively fast, the total amount of sCOD was only 75.4g COD. Lactate acid was the overall most prominent acid produced at 15.1 ± 0.1 g COD/L and propionate was the least at 0.574 ± 0.05 g COD/L. There was an initial one-day lag in the production of lactate acid which was suggested to be caused by the initial pH level.