Microorganisms have a critical role in the degradation of organic substances, and it plays an important role in the anaerobic degradation process 16. On the other hand, thermophilic bacteria is a type of organism that optimally grows and survives in relatively hot temperatures (temperature range 41–122 ☌), while the typical thermophilic condition is between 50 and 65 ☌ and 55 ☌ is optimum 15. The mesophilic bacteria is a type of organism that grows in a moderate temperature range of 20–45 ☌ with an optimum temperature of 35 ☌ 14. Different microorganism types have different suitable environmental conditions to survive. These microorganisms normally occur in a natural environment and play different roles in the process of waste anaerobic degradation. The microbial population and type of microbes play a significant role in AD and affect the composition of biogas, which is produced due to four groups of microorganisms, fermentative, syntrophic, acetogenic and methanogenic bacteria 11, 12, 13. The establishment of sustainable waste management practices that are effective, affordable, promote health and safety benefits to the public, prevent soil, air and water contamination, conserve natural resources, and provide renewable sources of energy that are generally environment friendly must be the priority. There are several possible uses of biogas such as in cooking, heating, electricity generation, etc. Biogas is mainly composed of methane and carbon dioxide, with trace elements of gases such as hydrogen sulfides, ammonia and water vapour. The AD is a series of processes in which microorganisms break down biodegradable material in the absence of oxygen for industrial or domestic purposes to manage waste and/or to release energy. One of the promising ways of dealing with such waste stream is through processing via anaerobic digestion (AD) to produce biogas 9, 10. On the other hand, using food waste as a potential source for the production of sustainable fuels will complete the full cycle of this waste stream sustainably and thus, directly support and facilitate the concept of the circular economy in the form of open-loop recycling 5, 6, 7, 8. Leachate could also pollute underground water and soil along with the release of methane which is a potent greenhouse gas with a short-term global warming potential that is 84 times more powerful than carbon dioxide 2, 3, 4. However, landfilling is expensive, requires space and can have a negative environmental impact if not well managed due to the production of leachate, methane and carbon dioxide and other nuisances like flies, odour, and vermin like birds and rodents. 1 confirmed that food waste is usually a major portion of any municipal solid wastes (MSWs) which are commonly disposed of in landfills or dumping sites, causing environmental problems. The high population growth rate and uncontrolled urbanization have created critical problems of solid waste disposal. This economic evaluation serves as a preliminary guide to assess the economic feasibility based on the fluctuating value of methane when producing biogas from food waste via anaerobic digestion, thus could help biogas project developers investigate similar scale scenarios. If waste management fee savings are to be incorporated, the total savings would be higher, increasing annual cash flows and enhancing financial results. Any prices above this rate yield a positive net present value (NPV) at $0.39/m 3 a discounted payback period of six years and a positive NPV of $3108 were calculated. An economic evaluation was conducted and showed that the case study breaks-even at $0.2944 per cubic metre. At day 21, the accumulative gas production value from mixed food waste samples was 1550 mL per 1 g of dry matter. Furthermore, polynomial models were used to predict the production of total gas and methane during the fermentation periods, which showed good matching between the theoretical and practical values with a coefficient of determination R 2 = 0.99. Our approach could potentially be applied within industry as the 24-h test can give a good indication of the potential substrate gas production as a quick test that saves time, with minimal effort required. Thus, we propose to use the 24-h time set to evaluate feedstock fermentation capacity that is intended for longer periods. The biogas production tests were at two-time sets 24-h and 21-day intervals and results showed a good correlation between those two-time sets. Herein, a techno-economic study is carried out on the potential of biogas production from different types of food waste generated locally. Food waste is a major constituent in municipal solid wastes and its accumulation or disposal of in landfills is problematic, causing environmental issues.
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