Technical and economic feasibility analysis on utilization of biogas from waste water treatment system in substitution of natural gas usage in steam boiler: A case study of chicken processing plant

Abstract

        The objective of this paperis to analyze the technical and economic feasibilities on utilization of biogas generated from waste water treatment system of chicken processing plant in substitution of natural gas usage for the 5 ton/hour of steam boiler. For technical feasibility analysis, the integrated system between the channel digester and up-flowanaerobic sludge blanket reactor was appropriate and designed for biogas generation system at 6,500 cu.m/day.For the economic analysis, it was found that, at the incremental investment of 60.94 million baht, 10-year project life, and minimum attractive rate of return of 12% per year, the NPV was at 27.13 million baht or in term of internal rate of return at 22.45% per year and 5.3 years of payback period. In dealing with risk analysis, the results of sensitivity analysis onthe uncertain parameters such as investment costs, natural gas price, volume of biogas generated from the waste water treatment system, and operating costs; and of the Monte Carlo simulation analysis on the natural gas price showed the project was technically and economically feasible for implementation with high return at low risk.