In order to alleviate the acid inhibition during acidogenesis of solid organic wastes, product-films accumulated around the substrates and microorganisms were hypothesized based on the diffusion of the acidogenic products in this study. Ultrsonic irradiation was introduced to destroy these product-films and promote the acidogenic performance. Direct ultrasonic irradiation could desorb acid from particle surfaces, and hence elevated the VS degradation rate from 0.8 to 1.3%/d. To advance the ultrasonic effect, fermentation broth from previous acidogenesis (volatile acid concentration was 11.0 g/L) was treated by the modified ultrasonic treatment (3-times-dilution-20-min -ultrasonic irradiation-filtration), and then fermented for 10 days in a rotational drum fermentation system. 68.2% of acid was removed from the substrate after treatment. At the end of the fermentation, the volatile acid increasing ratio (Rva) and VS degradation ratio (Rvs) were increased from 166.7 and 17.0 to 732.0% and 26.7%, respectively. The results demonstrated that ultrasonic irradiation alleviated the product inhibition and improved the acidogenic performance of solid organic wastes.%为缓解固体有机物酸化过程中产生的酸抑制,该文基于有机酸的产生和扩散方式,提出有机酸产物薄膜的假设,并利用超声波直接辐射和改进处理的方法处理酸化基质,比较处理前后酸化基质的物性变化及进一步的发酵性能.试验结果表明,超声波直接辐射可脱附积累在基质颗粒表面的有机酸,使基质发酵10d的挥发性固体日降解速率从未处理的0.8％提高到1.3％.为强化超声波空化效应和去除有机酸,将基质稀释后超声辐射20 min并增加过滤的改进超声波处理过程可使基质发酵l0d的有机酸增长率、挥发性固体降解率分别从未经超声波处理的166.7％、17.0％提高到732.0％、26.7％.改进超声波处理过程可有效缓解产物抑制,促进固体有机物的厌氧酸化性能,提高酸化速率.
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