Assessment of biowaste composting process for industrial support tool development through macro data approach

Area of Science:

• Environmental Science
• Waste Management
• Industrial Ecology

Background:

• Composting is crucial for sustainable waste management.
• Assessing composting efficiency and compost quality is vital for the industrial sector.
• Existing assessment methods may lack comprehensive indicators for industrial application.

Purpose of the Study:

• To develop and validate indicators for assessing composting efficiency and compost quality.
• To analyze the impact of plant size and technology on composting performance.
• To establish benchmarks for high-quality compost production.

Main Methods:

• Analysis of an 8-year dataset (2010-2017) from 17 composting plants.
• Evaluation of material flows (biowaste, yard trimmings, refuse, compost) and compost chemical characteristics.
• Development of indicators for improper fraction, yard trimmings ratio, mass losses, refuse generation, and plant saturation.
• Classification of plants by size and thermophilic phase technology.

Main Results:

• Average improper fraction: 10%, process losses: 68%, refuse generated: 25%, saturation: 79%.
• Smaller plants showed lower improper content, refuse, and saturation, but higher losses.
• Turned windrow technology correlated with higher improper fraction and yard trimmings ratio; vessel technology with lower losses and higher saturation.
• Compost quality improved when plant saturation was below 90% and improper fraction below 7%.

Conclusions:

• The developed indicators effectively assess composting processes and their relation to compost quality.
• Plant size and technology significantly influence composting efficiency and output.
• Optimizing plant saturation and minimizing improper fractions are key to achieving high-quality compost.