Impact of Alkaline H(2)O(2) Pretreatment on Methane Generation Potential of Greenhouse Crop Waste under Anaerobic Conditions

This paper intended to explore the effect of alkaline H(2)O(2) pretreatment on the biodegradability and the methane generation potential of greenhouse crop waste. A multi-variable experimental design was implemented. In this approach, initial solid content (3–7%), reaction time (6–24 h), H(2)O(2) concentration (1–3%), and reaction temperature (50–100 °C) were varied in different combinations to determine the impact of alkaline H(2)O(2) pretreatment. The results indicated that the alkaline H(2)O(2) pretreatment induced a significant increase in the range of 200–800% in chemical oxygen demand (COD) leakage into the soluble phase, and boosted the methane generation potential from 174 mLCH(4)/g of volatile solid (VS) to a much higher bracket of 250–350 mLCH(4)/gVS. Similarly, the lignocellulosic structure of the material was broken down and hydrolyzed by H(2)O(2) dosing, which increased the rate of volatile matter utilization from 31% to 50–70% depending on selected conditions. Alkaline H(2)O(2) pretreatment was optimized to determine optimal conditions for the enhancement of methane generation assuming a cost-driven approach. Optimal alkaline H(2)O(2) pretreatment conditions were found as a reaction temperature of 50 °C, 7% initial solid content, 1% H(2)O(2) concentration, and a reaction time of six h. Under these conditions, the biochemical methane potential (BMP) test yielded as 309 mLCH(4)/gVS. The enhancement of methane production was calculated as 77.6% compared to raw greenhouse crop wastes.