Food waste management and sustainable waste to energy: Current efforts, anaerobic digestion, incinerator and hydrothermal carbonization with a focus in Malaysia

In Malaysia, the challenge of managing the burgeoning volume of food waste in an environmentally sustainable manner is critical, given the country's rapid urbanization and the resulting increase in waste. This review article critically examines contemporary efforts and technologies in food waste management, focusing on anaerobic digestion (AD), incineration, and the emerging Hydrothermal Carbonization (HTC) technology, emphasizing their application within the Malaysian context. It is observed that landfills, currently the predominant method for waste disposal, contribute significantly to environmental degradation, highlighting an urgent need for sustainable alternatives. AD is identified as a beneficial approach, offering the dual advantages of waste volume reduction and biogas production; however, it is hindered by technical and economic challenges. Incineration, while effective in waste reduction and energy recovery, raises concerns regarding potential emissions of carcinogenic substances and its economic feasibility. The novel HTC technology, on the other hand, presents a promising avenue for converting food waste into Hydrochar, a carbon-rich product, demonstrating the potential for environmental sustainability and economic viability. The review underscores the imperative of optimizing these technologies to suit Malaysia's specific conditions, suggesting that future research should focus on enhancing HTC's application. This comprehensive evaluation aims to contribute to advancing sustainable food waste management practices, advocating for integrated solutions that are environmentally responsible, economically feasible, and socially acceptable.