Abstract
Coated paperboard beverage packaging is commonly captured in municipal recycling programs or sent directly to landfills. If coated paperboard is processed for making new recycled paper it generates sludges that are landfilled. Composting these paperboard products presents an opportunity to capture carbon, reduce landfill greenhouse gas emissions, and generate a beneficial soil amendment. This project assessed the degradation of coated paperboard during a 60-day period in a research-scale agitated, aerated compost system. Two treatments (surfactant and 24-hour presoaking with water) were used to promote biodegradation of the paperboard fibers. The addition of coated paperboard did not impact compost maturity and phytotoxicity. Paperboard tensile strength and dry mass per unit area decreased significantly between initial and final days but did not exhibit significant differences between treatments. Scanning electron microscope micrographs showed substantial change in fiber structure due to degradation, as well as strong indications of fungal mycelia throughout the paper fibers. The treatments did not significantly impact the temperature and carbon dioxide flux trends. Overall, the use of coated paperboard as a feedstock did not adversely affect the composting process. As expected, the paperboard degraded slowly and was easily detected visually in the compost at the conclusion of the trial period.