Biological treatment of compost leachate: Assessing the efficacy of composting process and bioaugmentation of composting piles

A significant portion of municipal solid waste (MSW) in developing countries is organic, making composting an environmentally friendly solution for managing this waste stream. However, the composting process generates substantial amounts of leachate, posing challenges to its efficiency. This study evaluated the effectiveness of composting piles, with and without mature compost inoculation, in treating leachate under field conditions. We conducted physicochemical and biological analyses throughout the composting process and on the final product to assess the role of MSW composting in the simultaneous treatment of leachate. Our results revealed that composting piles have the capacity to treat added leachate at concentrations of 10% and 20% as a moistener. All piles achieved high temperatures and significant organic matter reduction. Notably, the compost pile inoculated with mature compost and moistened with 10% leachate exhibited exceptional efficiency in leachate treatment, producing a high-quality end product that met standard requirements. Additionally, this method can reduce operating costs for compost leachate treatment by 23-30%. Overall, the composting piles inoculated with mature compost effectively adapted to the adverse conditions posed by leachate and successfully treated pollutants. • Composting plants face challenges due to the production of leachate from composting process. • Compost piles with their specific characteristics offer potential for treating leachate. • Inoculating piles with mature compost creates conditions for effective leachate treatment. • Utilizing composting piles can reduce operating costs of leachate treatment by one-third.