Poultry Litter Solid State Anaerobic Digestion: Effect of Digestate Recirculation Intervals and Substrate/Inoculum Ratios on Process Efficiency

摘要: This study evaluated the effect of substrate:inoculum ratio and digestate recirculation conditions on biogas methane yield, free ammonia concentration solid phase agronomic quality (after treatment) poultry litter state anaerobic digestion (SSAD). Experimental tests were conducted using a central composite design (2²), with four trials at factorial points three points, as substrate that was collected after 12 cycles broiler production (TS 76% (w.w-1)). Three laboratory-scale reactors containing 3 kg each operated mesophilic (37°C) seven experimental runs performed retention time 30 days each. There ratios (1:1; 1:1.66 1:3) daily intervals (2, 4 times per day), event lasted 15 min. The highest yields were183 LNbiogas.kgVSadd-1and 74 LNmethane.kgVSadd-1, respectively, they obtained 1:3 frequency day. Digestate variable influenced ammonia; most frequently recirculated had lower concentrations (below 60 mgNH3.L-1). After SSAD process, we identified transfer nutrients (N, P, K) from to liquid phase. nutrient in (Nout = 11 g.kg-1, Kout=5 g.kg-1 Pout 7 g.kg-1) indicated digested still has potential for use fertilization. In this study, it estimated 90 m³biogas.tonspoultrylitter-1 generated SSAD. Whereas 100 tons are produced cycles, generation capacity reaches 9,000 m³/year. scenario, farmers can an additional source energy.n 9000 energy.