Anaerobic Digestion of Corn Stover Pretreated with Sulfuric Acid in Different Soaking Durations

Abstract

The biogas production of pretreated corn stover has been determined in different soaking durations. Batch anaerobic digestion applies three different soaking durations in sulfuric acid pretreatment under room temperature. The study aimed to probe the effect of soaking durations during sulfuric acid pretreatment. The experiment was conducted in 600 mL digesters at room temperature. Biogas volume was measured using the water displacement method every three days. The observed cumulative biogas yields varied between 48.74 mL/g VS and 99.95 mL/g VS. The highest biogas yield was obtained when corn stover was soaked in sulfuric acid for 6 hours. The 24 h-pretreated corn stover got the lowest biogas yield. The statistical result proved a significant effect of soaking durations on biogas production (p < 0.05). The logistic model provided a better fit than the first-order model, with R2 values ranging from 0.9923 to 0.9987 and divergence between experimental and predicted values varying between 0.12% and 1.48%.