The process instability of anaerobic digestion (AD) is a common issue and may result in underperformance or short-term process failure. Extensive research has shown that total solids (TS) content in AD has a significant impact on system stability and performance. However, no study has examined the feasibility of stabilizing the AD process by maintaining constant TS content in the digestate. In this study, an innovative control approach based on constant TS content in the digestate during AD was developed using a mass balance equation. Two levels of TS content (desired values of 4% wet basis (w.b.) and 6% w.b.) were compared with conventional control. The process stability was examined by monitoring digestate components and pH. Substrate-specific methane yield (m³ CH₄/kg VS) was used to assess the effectiveness of the controlled conditions. The results showed that the digestate TS content during AD can be controlled and that the digestion process can be stabilized by controlled conditions. In addition, constant TS in the digestate (within 1% w.b. of the desired level) gave increased levels of biogas production (10.2%), methane (13.5%), and substrate-specific methane yield (43.3%) at 4% TS, and respective increases of 16.6%, 21.2%, and 20.8% at 6% TS when compared with standard operation.

中文翻译：

---

通过恒定的Digestate固体含量来稳定厌氧消化过程

厌氧消化（AD）的过程不稳定是一个常见问题，可能导致性能不佳或短期过程失败。广泛的研究表明，AD中的总固体（TS）含量对系统稳定性和性能有重大影响。然而，没有研究检查通过保持消化物中恒定的TS含量来稳定AD过程的可行性。在这项研究中，基于质量平衡方程，开发了一种基于AD中消化液中TS含量恒定的创新控制方法。将TS含量的两个水平（湿基（wb）的期望值和wb的6％的期望值）与常规对照进行了比较。通过监测消化成分和pH值来检查过程稳定性。特定于底物的甲烷产率（m ³ CH ₄/ kg V​​S）用于评估控制条件的有效性。结果表明，可以控制AD期间消化TS的含量，并且通过控制条件可以稳定消化过程。此外，消化液中的TS恒定（在所需水平的1％wb以内）在4％TS时提高了沼气产量（10.2％），甲烷（13.5％）和底物比甲烷产率（43.3％），与标准作业相比，在6％TS时分别增加了16.6％，21.2％和20.8％。