Abstract:

Ventilation rate is an important limiting factor that affects the quality of aerobic fermentation products of food waste and is vital to the success of aerobic fermentation. By adjusting the ventilation rate during the fermentation process, the oil degradation and the generation and accumulation of organic acids in food waste were controlled, and the limited acidification of the fermentation process could be achieved. It not only reduced the volatilization and loss of NH₃, but also improved the quality of fermentation products. The results of this study showed when the ventilation rate of aerobic fermentation piles increased, the peak temperature of the fermentation piles increased, but the high-temperature period was shortened, with the organic matter degradation rate and pile maturity firstly increasing and then decreasing. As the ventilation rate was 0.2L/(L·min), the aerobic fermentation efficiency of food waste pile was better. The greater the ventilation rate during the aerobic fermentation of food waste, the lower the accumulated volatilization of NH₃. When the ventilation rate was 0.1L/(L·min), the high temperature period was longer, which was not conducive to the growth and reproduction of nitrifying microorganisms for the conversion of NH₃ to NO _x^-, and NH₃ emissions were the highest. When the ventilation rate was 0.3L/(L·min), the high-temperature period was the shortest, and water loss of piles was severe, while organic matter degradation was not complete, and NH₃ volatilization was also the lowest. Compared with the absence of self-made oil removal microbial inoculants (ORMI), the addition of ORMI effectively enhanced the aerobic fermentation of food waste. At the end of aerobic fermentation, the oil degradation rate, seed germination index and total nutrient content were increased by 23.08%, 29.48% and 7.36%, respectively. The ventilation rate affected the activities of relevant microorganisms and lipase enzyme, further influenced the degradation of oil and accumulated volatilization of ammonia, and ultimately promoted the maturity and total nutrient content of the aerobic fermentation products.

Key words: fermentation, ventilation rate, limited acidification, food waste

摘要：

通风量是影响食品废弃物好氧发酵产物质量且关系过程成败的重要制约因素。本文通过调整发酵过程中的通风量，控制食品废弃物中油脂的降解与有机酸的产生和累积，实现发酵过程的有限酸化，不仅可减少NH₃挥发与流失，还可提高发酵产物的质量。研究结果表明，随着通风量增大，发酵物料的峰温度升高，但高温期缩短，有机质降解率和腐熟度先升高后降低，当通风量为0.2L/(L·min)时，发酵效果较佳。通风量越大，NH₃累积挥发量越低。通风量为0.1L/(L·min)时，高温期较长，不利于硝化微生物的生长繁殖，NH₃排放量最大。通风量为0.3L/(L·min)时，高温期最短，同时水分散失严重，有机物降解不彻底，NH₃挥发量也最低。与未添加自制除油微生物菌剂（ORMI）相比，接种ORMI可以有效促进食品废弃物好氧发酵的效果，发酵结束时，油脂降解率、种子发芽指数和总养分含量分别提高了23.08%、29.48%和7.36%。通风量通过影响相关微生物活性及脂肪酶酶活促进油脂降解，减少氨的累积挥发量，最终有效提升发酵产物的腐熟度和总养分含量。

关键词: 发酵, 通风量, 有限酸化, 食品废弃物