3.2. Effect of volatile solids on gas production
Gas accumulation was observed daily in reactors containing different amounts of poultry litter. The daily gas accumulation in the different reactors was used to determine the peak gas production as related to the initial volatile solid concentration. The relationship between periods of peak gas production and the initial volatile solid concentration in the different reactors is shown in Fig. 3, which shows that peak gas generation occurred earlier when the volatile solids concentration was higher. The lower the initial VS concentration, the more time required for peak gas production in the reactor.