THE Economic Assesment On Bottom Ash Utilizing As The Bio Coal Fuel

Abstract

Coal bottom ash was included in Hazardous and Toxic Waste (LB3), which requires seriously manage not to warm the environment and humans health. LB3 management becomes an obligation for the industry which producing it and being a burden in itself due to the project of waste utilization often regarded as the high-cost investment projects or less profitable. This study aims to conduct an economic assessment of pilot-scale projects to reuse bottom ash to support the clean industry strategy. The study mixed coal bottom ash with biomass from municipalities solid waste (MSW), called bio-coal fuel. These raw materials were combined with a composition 60%:40% weight (bottom ash: biomass) to be briquette form by adding amylum as a binder. This study used the benefit-cost analysis approach to assess economic feasibility. Tree indicators used in this study were net benefit-cost ratio, payback period, and return on investment. These indicators provided the company policy to continue or stop this project. The finding study showed that the company got a payback period and the net benefit from the ninth year. The company also achieved a net B/C ratio was more than one, and ROI was 1.09 times in the ninth year. The other beneficiaries acquired by the company was included external costs, such as risks from commitment failure by third parties in coal waste management, costs rising risk of purchasing coal, and given a positive value for providing employment.

Optimizing Utilization of Hazardous Waste and Biomass as Solid Fuel for Co-Firing

“…Briquettes are made from a mixture of the four raw materials with variations in milk composition according to Table 1, and mixed with an adhesive material in the form of tapioca starch (amylum) which is thickened beforehand using water with the ratio of amylum and water is 1:10 (Marganingrum et al, 2021). The adhesive used was tapioca starch (organic adhesive) as much as 5% of the total weight of raw materials to be made into briquettes.…”

“…This TOX parameter is indicated by the chlorine content contained in the raw materials and briquette products. Based on research conducted by Marganingrum et al (2021), samples of WWTP sludge, bottom ash, and biomass have chlorine contents of 0.19%; 0.05%; and 0.43. These results have met the criteria of PerMen LHK 06/2021, and indicate that the samples are safe for the environment.…”

“…However, these three studies did not make briquettes with a mixture of fly ash, which is produced from the process of burning coal in boilers. From various studies on the utilization of fly ash, not many studies have discussed the utilization of fly ash as one of the raw materials for briquettes, usually fly ash is used for road construction, embankments, building materials, geopolymer applications, and cement production (in the field of civil engineering), so it is necessary to conduct research on briquettes to be used as a companion fuel with a mixture of raw materials, namely fly ash and bottom ash (FABA), WWTP sludge, and biomass from fermented urban waste (Marganingrum et al, 2021).…”