Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, via Di Biasio 43, 03043, Cassino, FR, Italy; LBE, Univ. Montpellier, INRA, 102 Avenue des Etangs, 11100, Narbonne, France.
Department of Civil, Architectural and Environmental Engineering, University of Napoli Federico II, via Claudio 21, 80125, Napoli, Italy.
Water Res. 2019 Nov 1;164:114932. doi: 10.1016/j.watres.2019.114932. Epub 2019 Jul 30.
High-solids anaerobic digestion (HS-AD) of the organic fraction of municipal solid waste (OFMSW) is operated at a total solid (TS) content ≥ 10% to enhance the waste treatment economy, though it might be associated to free ammonia (NH) inhibition. This study aimed to calibrate and cross-validate a HS-AD model for homogenized reactors in order to assess the effects of high NH levels in HS-AD of OFMSW, but also to evaluate the suitability of the reversible non-competitive inhibition function to reproduce the effect of NH on the main acetogenic and methanogenic populations. The practical identifiability of structural/biochemical parameters (i.e. 35) and initial conditions (i.e. 32) was evaluated using batch experiments at different TS and/or inoculum-to-substrate ratios. Variance-based global sensitivity analysis and approximate Bayesian computation were used for parameter optimization. The experimental data in this study permitted to estimate up to 8 biochemical parameters, whereas the rest of parameters and biomass contents were poorly identifiable. The study also showed the relatively high levels of NH (i.e. up to 2.3 g N/L) and ionic strength (i.e. up to 0.9 M) when increasing TS in HS-AD of OFMSW. However, the NH non-competitive function was unable to capture the acetogenic/methanogenic inhibition. Therefore, the calibration emphasized the need for target-oriented experimental data to enhance the practical identifiability and the predictive capabilities of structured HS-AD models, but also the need for further testing the NH inhibition function used in these simulations.
高固体厌氧消化（HS-AD）的有机废物（OFMSW）的一部分是在总固体（TS）含量≥10%的运行，以提高废物处理的经济效益，虽然它可能与游离氨（NH）的抑制作用有关。本研究旨在校准和交叉验证用于均相反应器的 HS-AD 模型，以评估高 NH 水平对 OFMSW 的 HS-AD 的影响，但也要评估可逆非竞争性抑制功能是否适合再现 NH 对主要产酸和产甲烷菌群的影响。使用不同 TS 和/或接种物-底物比的分批实验评估了结构/生化参数（即 35 个）和初始条件（即 32 个）的实际可识别性。方差全局敏感性分析和近似贝叶斯计算用于参数优化。本研究中的实验数据允许估计多达 8 个生化参数，而其余参数和生物质含量则难以识别。该研究还表明，当 OFMSW 的 HS-AD 中 TS 增加时，NH（即高达 2.3 g N/L）和离子强度（即高达 0.9 M）的相对水平较高。然而，NH 非竞争性函数无法捕获产酸/产甲烷抑制作用。因此，校准强调了需要针对目标的实验数据来提高结构化 HS-AD 模型的实际可识别性和预测能力，同时也需要进一步测试这些模拟中使用的 NH 抑制功能。
