Economic and Technological Feasibility Analysis of Biogas Production from Biomass Wastes by Adding Hydro char and Hydrothermal Pre-treatment

Abstract

Anaerobic digestion is an effective method of treating animal wastes and biomass wastes, reducing pollution by them and producing regenerative energy in the form of methane (methane gas). As renewable bioenergy resources, fish processing wastes, tofu residue and lignocellulose biomass (bamboo residue and rice straw) are identified as cheap and have a wide range of sources, so they can be used as an effective substrate for biogas production. When fish processing waste with additive Hydro char (200°C and 220°C), hydrothermal pretreated tofu residue (140°C) and lignocellulose biomass (rice straw: 160°C) are subjected to anaerobic co-digestion, biogas production can be increased. In addition, when liquid fraction from hydrothermal carbonization (200°C-280°C) and fish processing wastes are mixed in a certain ratio and used as raw materials for anaerobic digestion to carry out anaerobic co-digestion, optimal output of biogas can be produced. This paper aims at the technology of producing biogas and maximizing the production by anaerobic digestion of fish processing wastes and tofu residue with Hydro char obtained from bamboo residue at a certain temperature (200°C) according to hydrothermal carbonization, and making an economic and technological analysis of production process. Through a Break-even point analysis, producing biogas using hydrothermal Pre-treatment and adding Hydro char has more advantages than the without Pre-treatment method in both production volume and investment recovery duration. It was demonstrated that the comparison and evaluation of without Pre-treatment and adding Hydro char, hydrothermal Pre-treatment approach, the investment recovery duration could be reduced from 419 days to 256 days with the large-scale biogas plants of 1 000 m3 as a criterion.