Investigation of the effect of various support materials on biogas production from poultry manures

In this study, the effects of various support materials on biogas production and biogas yield from anaerobic digestion of poultry manure released into the environment were investigated. The present work was carried out in three parts. In the first part, the effects of the parameters such as the amount of solid matter (A/A, %), the inoculum ratio (%), the amount of raw pumice used as support material (g/L) and the particle size of the pumice (mm) that affect the production of biogas from poultry manure have been investigated. They are optimized and modelled by using response surface methodology (RSM). In the second part, the effects of nickel (Ni) and molybdenum (Mo) trace metal supported pumice minerals have been studied separately. In this section, the effects of parameters such as the amount of solid matter (A/A, %), metal ratio by weight (%), and the amount of trace metal supported pumice minerals added to the anaerobic system (mg/L), which affect the biogas production efficiency, have been examined. They are optimized and modelled by RSM. As a result of experimental studies, in the first part, optimum conditions for cumulative biogas production based on numerical analysis; The amount of solid matter was 8.92%, the inoculum ratio was 26%, the pumice amount as support material 6.39 g/L and the particle size of the support material was 1.77 mm. Under these optimum conditions, the cumulative biogas production was determined as 8965.87 mL. Optimum conditions for %CH4; The amount of solid matter was 9.19%, the inoculum ratio was 25.84%, the pumice amount as support material 6.26 g/L and the particle size of the support material was 1.73 mm. Under these optimum conditions, %CH4 was determined as 71.298%. Optimum conditions for COD removal efficiency; The amount of solid matter was 8.10%, the inoculum ratio was 24.62%, the pumice amount as support material 7.04 g/L and the particle size of the support material was 1.76 mm. Under these optimum conditions, COD removal efficiency was determined as 68.4711%. In the second section, optimum conditions for cumulative biogas production based on numerical analysis in studies with Ni loaded pumice minerals (Ni@IP); The amount of solid matter was 8.80%, Ni ratio by weight was 16.83%, and the amount of Ni@IP was 17.02 mg/L. Under these optimum conditions, the cumulative biogas production was determined as 7862.75 mL. Optimum conditions for %CH4; The amount of solid matter was 8.49%, Ni ratio by weight was 16.85%, and the amount of Ni@IP was 17.61 mg/L. Under these optimum conditions, %CH4 was determined as 63.49%. Optimum conditions for COD removal efficiency; The amount of solid matter was 8.44%, Ni ratio by weight was 16.74%, and the amount of Ni@IP was 16.93 mg/L. Under these optimum conditions, COD removal efficiency was determined as 60.43%. In the second section, optimum conditions for cumulative biogas production based on numerical analysis in studies with Mo loaded pumice minerals (Mo@IP); The amount of solid matter was 8.85%, Mo ratio by weight was 5.12%, and the amount of Mo@IP was 5.76 mg/L. Under these optimum conditions, the cumulative biogas production was determined as 7372.79 mL. Optimum conditions for %CH4; The amount of solid matter was 9.15%, Mo ratio by weight was 5.29%, and the amount of Mo@IP was 7.16 mg/L. Under these optimum conditions, %CH4 was determined as 62.67%. Optimum conditions for COD removal efficiency; The amount of solid matter was 8.43%, Mo ratio by weight was 4.15%, and the amount of Mo@IP was 7.66 mg/L. Under these optimum conditions, COD removal efficiency was determined as 55.15%. The results showed that RSM has been successfully applied to predict and model biogas production from anaerobic digestion of poultry manure. In the third section, the bi-metallic effects of Ni and Mo trace metal supported pumice minerals on biogas production were investigated. In this section, it has been determined that Ni-Mo trace metal pumice support materials (NiMo@IP) have a more bio-stimulating effect on biogas production than without support material and Ni-Mo without trace metal.