Effect of natural zeolite (clinoptilolite) on ammonia emissions of leftover food-rice hulls composting at the initial stage of the thermophilic process
The study investigates the impact of natural zeolite, specifically clinoptilolite, on ammonia emissions during the composting of leftover food mixed with rice hulls, particularly focusing on the initial thermophilic stage of the composting process. Conducted in seven controlled fermenters, the research varied the amount of clinoptilolite added (ranging from 0% to 47.2% on a dry mass basis) to assess its effectiveness in reducing ammonia emissions.
The findings indicate that the optimal doses of clinoptilolite for minimizing ammonia emissions were between 31.5% and 47.2%. The study highlights that clinoptilolite functions as an adsorbent, effectively capturing ammonia during the composting process. The research also emphasizes the importance of temperature in ammonia emission, noting that emissions typically begin when temperatures exceed 45°C, with significant increases observed at higher temperatures.
The methodology involved collecting leftover food waste from schools, mixing it with rice hulls and clinoptilolite, and monitoring various parameters such as temperature, moisture content, and ammonia concentration over a seven-day composting period. Results showed that higher doses of clinoptilolite correlated with lower ammonia emissions, particularly in the later stages of the thermophilic process. The study concludes that clinoptilolite can significantly enhance the composting process by reducing odor emissions, thereby making composting more environmentally acceptable, especially in urban settings.
This research paper is significant in the field of agricultural meteorology and waste management as it addresses the critical issue of ammonia emissions during composting, which can lead to environmental pollution and odor problems, particularly in urban agriculture. By demonstrating the effectiveness of clinoptilolite in reducing these emissions, the study contributes to ongoing discussions about sustainable waste management practices and the utilization of food waste in urban agriculture. The findings offer practical insights for composting facilities and urban farmers, highlighting the potential for clinoptilolite to improve compost quality and reduce environmental impacts. This research is particularly beneficial for policymakers and practitioners seeking to enhance urban agriculture's sustainability and efficiency.
