Abstract

In a distillery, controlled wet oxidation of biomethanated spent wash improves biogas recovery and subsequent biodegradation of wash water. This work is a model compound study on wet air oxidation (WAO) of four inhibitory organic compounds present in spent wash: 5-hydroxymethyl furfuraldehyde (HMF), p-coumaric acid (PCA), oleic acid (OA), and t-butyl alcohol (TBA). Using homogeneous ferrous sulfate catalyst (loading 16–48 mg/L) in a batch reactor, wet oxidation was studied between 175 and 230 °C at 0.69, 1.38, and 2.07 MPa oxygen partial pressure. Low molecular weight organic acids were formed during the oxidation process. At T = 230 °C, BOD/COD values as high as 0.87, 0.74, 0.66, and 0.58 were achieved for the reactions with HMF, PCA, OA, and TBA. Power law modeling suggested first-order kinetics of destruction of total organic carbon (TOC). From Arrhenius plots, the activation energy values were determined. This model compound study will improve our understanding of the reactivity of toxic and refractory compounds of wash water in the oxidation process.

摘要

在酿酒厂中，生物甲烷化废洗涤液的受控湿式氧化可提高沼气回收率和洗涤水的后续生物降解。这项工作是对废洗涤液中存在的四种抑制性有机化合物的湿空气氧化 (WAO) 的模型化合物研究：5-羟甲基糠醛 (HMF)、对香豆酸 (PCA)、油酸 (OA) 和叔丁基酒精（待定）。在间歇反应器中使用均相硫酸亚铁催化剂（负载 16–48 mg/L），在 0.69、1.38 和 2.07 MPa 氧分压下，在 175 至 230 °C 之间研究湿式氧化。在氧化过程中形成低分子量有机酸。在T = 230 °C，与 HMF、PCA、OA 和 TBA 的反应达到了高达 0.87、0.74、0.66 和 0.58 的 BOD/COD 值。幂律模型提出了总有机碳 (TOC) 破坏的一级动力学。从阿伦尼乌斯图中，确定了活化能值。该模型化合物研究将提高我们对氧化过程中洗涤水中有毒和难降解化合物的反应性的理解。