Propionic acid metabolism during anaerobic biowaste treatment - Comparison of different digestion regimes

丙酸盐在厌氧沼气池的启动、重启和工艺失衡过程中积累，在达到稳态条件时迅速减少。在这个项目中，将研究不同厌氧消化器或消化机制下生物废物（卡尔斯鲁厄）或市场废物（印度尼西亚万隆）中丙酸盐的形成和降解。将在卡尔斯鲁厄研究组成、pH值、缓冲液和（生物可利用的）微量金属对丙酸形成和降解、冲击负荷或沼气池重启的影响。在不同的反应器系统和不同的底物中，通过甲基丙二酰辅酶a或非随机c6分解途径降解丙酸将通过脉冲添加特异性14c标记的丙酸进行研究。结果可以得出主要丙酸降解剂类型的结论。在印度尼西亚万隆LIPI，将对市场废物悬浮液的一级或两级消化（产丙酮和产甲烷阶段分离）CSTR反应器系统进行优化，在印度尼西亚万隆ITB，废物将首先分离为液体和固体相，然后在固定床反应器（液体）或干发酵系统（固体）中消化两部分。这种工艺替代方案是废水处理的最新技术，但即使在欧洲，生物废物或生物废物馏分的经验也很少。

Propionate accumulates during start-up, restart and process imbalances in anaerobic biowaste digesters and rapidly decreases when obtaining steady-state conditions. In this project, propionate formation and degradation in biowaste (Karlsruhe) or market wastes (Bandung/Indonesia) in different anaerobic digesters or digestion regimes will be investigated. The influence of composition, pH, buffers and of (bioavailable) trace metals on propionate formation and degradation, shock-loading or restart of digesters will be investigated in Karlsruhe. Propionate degradation via the methylmalonyl-CoA or non-randomizing C6-dismutation pathway in different reactor systems and with different substrates will be investigated with pulse addition of specifically 14C-labeled propionate. Results should allow conclusions on the type of predominant propionate degraders. At LIPI, Bandung/Indonesia, the digestion of market waste suspensions in one stage or two-stage (acetogenic and methanogenic stage separated) CSTR reactor systems will be optimized and at ITB, Bandung/Indonesia, waste will first be separated into a liquid and solid phase and both fractions will then be digested either in a fixed-bed reactor (liquid) or in a dry fermentation system (solids). Such process alternatives are state of the art for wastewater treatment, but even in Europe experience with biowaste or biowaste fractions is scarce.