Aerated Static Pile Composting for Industrial Biowastes: From Engineering to Microbiology

Area of Science:

• Environmental Science
• Microbiology
• Waste Management

Background:

• Soybean curd residue is a common biowaste with disposal challenges.
• Industrial-scale composting requires optimized conditions for efficient biowaste treatment.

Purpose of the Study:

• To demonstrate the feasibility of an industrial-scale aerated static pile composting system for soybean curd residue.
• To optimize feedstock mixing ratios and assess compost maturity.
• To analyze the microbial community involved in the composting process.

Main Methods:

• Optimized feedstock mixing ratios for carbon-nitrogen (25-35) and moisture (60-70%) levels.
• Utilized an open-air aerated static pile composting system over 6-7 months.
• Assessed compost maturity using Solvita and seed germination tests.
• Performed metagenomic analysis to identify bacterial and fungal communities.

Main Results:

• Achieved mature compost within 6-7 months.
• 25% compost extract concentration showed the best germination index without phytotoxicity.
• Identified unique bacteria (e.g., *Thermoactinomyces* spp.) and fungi (e.g., *Diutina rugosa*) crucial for biowaste degradation.

Conclusions:

• Industrial-scale aerated static pile composting is a feasible method for treating soybean curd residue.
• Optimized conditions and microbial communities contribute to effective biowaste composting.
• The mature compost is suitable for application, confirmed by germination tests.