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为了研究餐厨垃圾固态发酵过程中挥发性脂肪酸(VFAs)与产气的变化关系,采用中温(37.0±0.2)℃连续式发酵,在完全混合CSTR反应器中连续运行100 d,分析餐厨垃圾固态发酵过程的启动、运行、失衡、失衡后恢复及实现固态发酵全过程各参数的变化趋势,重点研究VFAs各成分与产气、pH等的关系.结果表明,餐厨垃圾固态发酵实验过程可划分为4个时期:适应期(0～13 d)、启动期(14～30 d)、抑制期(31～50d)、恢复及稳定期(51～100 d).不同时期的容积产气率、VFAs及各参数均表现出不同的阶段性变化.在餐厨垃圾固态发酵全过程中,pH保持在5～7之间,正丁酸比例一直处于较高水平;VFAs与pH和容积产气率在初期基本保持反比关系,最终在稳定期达到平衡,均稳定在一定范围内波动.在恢复及稳定阶段以NaOH稀碱液调节当日回流渗滤液的pH值,在第63 d时pH值上升至6.76,VFAs含量稳定在20～22 g·L-1之间,产气量明显提高;在81 d时TS达到20％以上,系统容积产气量和生物降解率均保持相对稳定.“,”In order to study the correlation between volatile fatty acids (VFAs) and gas production during solid-state fermentation of food waste,continuous fermentation was carried out in medium temperature (37.0-±0.2) ℃ for 100 d in a fully mixed CSTR reactor.The start-up,operation,imbalance,recovery after unbalance and the change trend of solid-state fermentation process parameters were analyzed.The relationship between VFAs components and gas production,pH and so on was mainly studied.The results showed that the solid-state fermentation process of food waste can be divided into four periods:adaptation period (0～ 13 d),start-up period (14～30 d),inhibition period (31～50 d),and recovery and stable stage (51 ～ 100 d).Volume loading rate (VLR),VFAs and the parameters all showed different stages of change in different periods.In the whole process of solid-state fermentation of food waste,the pH was kept between 5 and 7,and the proportion of n-butyrate was always at a high level.VFAs maintained an inverse relationship with pH and in the initial stage,finally in the stable stage to reach equilibrium and stable in a certain range of fluctuations.In the recovery and stable stage,the pH value of the reflux leachate was adjusted to 6.76 at the 63th day with NaOH dilute alkali solution,the content of VFAs was stabilized at 20～22 g·L-1,and the gas production was increased obviously.The TS increased more than 20％ in 81 d,and the VLR of the system and the biodegradation rate were relatively stable.