Department of Applied Bioeconomy, Wrocław University of Environmental and Life Sciences, Wrocław, Poland.
USDA-ARS Conservation and Production Research Laboratory, Bushland, Texas, United States of America.
PLoS One. 2024 Mar 8;19(3):e0290206. doi: 10.1371/journal.pone.0290206. eCollection 2024.
To date, only a few studies focused on the carbon monoxide (CO) production during waste composting; all targeted on CO inside piles. Here, the CO net emissions from compost piles and the assessment of worker's occupational risk of exposure to CO at large-scale composting plants are shown for the first time. CO net emissions were measured at two plants processing green waste, sewage sludge, or undersize fraction of municipal solid waste. Effects of the location of piles (hermetised hall vs. open yard) and turning (before vs. after) were studied. Higher CO net emission rates were observed from piles located in a closed hall. The average CO flux before turning was 23.25 and 0.60 mg‧m-2‧h-1 for hermetised and open piles, respectively, while after- 69.38 and 5.11 mg‧m-2‧h-1. The maximum CO net emissions occurred after the compost was turned (1.7x to 13.7x higher than before turning). The top sections of hermetised piles had greater CO emissions compared to sides. Additionally, 5% of measurement points of hermetised piles switched to 'CO sinks'. The 1-h concentration in hermetised composting hall can reach max. ~50 mg CO∙m-3 before turning, and >115 mg CO∙m-3 after, exceeding the WHO thresholds for a 1-h and 15-min exposures, respectively.
迄今为止，只有少数研究关注废物堆肥过程中的一氧化碳（CO）产生，且所有研究都针对堆内的 CO。本研究首次展示了堆肥过程中 CO 的净排放量，以及在大型堆肥厂评估工人接触 CO 的职业风险。本研究在两个处理绿色废物、污水污泥或城市固体废物小粒径部分的工厂中测量了 CO 净排放量。研究了堆垛位置（密封大厅与露天堆场）和翻堆（翻堆前与翻堆后）的影响。在密封大厅中，CO 的净排放率更高。翻堆前，密封和露天堆的平均 CO 通量分别为 23.25 和 0.60 mg·m-2·h-1，翻堆后分别为 69.38 和 5.11 mg·m-2·h-1。最大的 CO 净排放发生在堆肥翻堆后（比翻堆前高 1.7 到 13.7 倍）。与侧面相比，密封堆的顶部区域有更高的 CO 排放。此外，密封堆的 5%测量点转变为“CO 汇”。在翻堆前，密封堆肥大厅的 1 小时浓度可达最大值~50 mg CO·m-3，翻堆后可达>115 mg CO·m-3，分别超过了世卫组织 1 小时和 15 分钟暴露的阈值。
