餐厨垃圾堆肥理化特性变化规律研究

Study on the Change of Physicochemical Characteristics of Food Wastes During Aerobic Composting

餐厨垃圾主要包括厨余和泔脚,二者的化学组成、物料结构以及初始微生物量均存在差异.对厨余和泔脚分别与相同质量比的木屑混合堆制的一次好氧堆肥过程进行了比较研究.结果表明,在相同好氧堆肥条件下,二者的特性变化不同:与厨余堆肥系统相比,泔脚堆肥系统初始水溶性w(C)/w(N)高,堆肥pH较低,高温持续时间长,CO2释放率高,NH3挥发少,氮素损失低,堆制后堆肥含氮量升高;但泔脚一次堆肥所需时间偏长,应采取有效方法加速其堆肥进程.厨余堆肥系统升温快,堆肥周期短,但生物可利用碳的短缺造成系统氮素损失量大,可采用在厨余堆肥中添加适当碳源等措施来减少氮素损失.

Food wastes were generally classified into pre-consumer food wastes and post-consumer food wastes. These two types of food wastes were different especially in chemical composition, material structure and initial microbial biomass. The aerobic composts, which mixed preconsumer food waste and post-consumer food wastes respe-ctively with same amount of sawdust, were compared. The result indicated that they have different characteristic under the same conditions of aerobic compost process. Compared to pre-consumer food wastes, the post-consumer food wastes composting had higher water solubility carbon to nitrogen ratios, lower pH of the compost material, longer lasting time of high temperature phase, higher discharge of CO2, lower loss of nitrogen and increased nitrogen content of material after composing. However post- consumer food wastes composting cost more time, and effective method should be taken to accelerate compost process. The pre-consumer food wastes composting can increase its temperature rapidly and shortened composting time, but the lack of available carbon caused more loss of nitrogen of the pre-consumer food wastes composting. The loss of nitrogen can be reduced by adding appropriate carbon to pre-consumer food wastes.