Department of Biological Systems Engineering, Washington State University, Pullman, WA, USA.
Sustainable Biofuels and Co-products Research Unit, Eastern Regional Research Center, US Department of Agriculture, Agricultural Research Service, Wyndmoor, PA, USA.
Waste Manag Res. 2024 Mar;42(3):206-217. doi: 10.1177/0734242X231180652. Epub 2023 Jul 24.
Wet oxidation can be an effective process for the pretreatment of complex biomass such as lignocellulose. However, studies on the use of wet oxidation for treating solid waste such as dairy manure are limited. The use of partial wet oxidation to convert dairy manure into low molecular weight carboxylic acids as final products were investigated. This work focuses on the performance of the sub-critical wet oxidation treatment of dairy cattle manure as a conversion/pretreatment process to release matter from the lignocellulosic fraction rather than a destructive process. The operating conditions were controlled at the short residence time and optimal temperature in the presence of oxygen under a pressure of 120 psi. The thermal hydrolysis under wet oxidation significantly affected conversion manure slurry into organic acids. The concentration of acetic acid reached 1778 mg L, achieved at 190°C (60 minutes reaction time) as the reaction temperature increased within the range of 150°C-200°C, total organic carbon was reduced and monomers in the process liquids decreased. On the other hand, soluble COD in process liquids increased with an increment in reaction temperature. The results provide insights into technical options to pretreat dairy manure to improve biochemical conversion yield.
湿式氧化可以有效地预处理复杂的生物质，如木质纤维素。然而，关于湿式氧化处理固体废弃物（如奶牛粪便）的研究有限。本研究采用部分湿式氧化法将奶牛粪便转化为低分子量羧酸作为最终产物。本工作重点研究了亚临界湿式氧化处理奶牛粪便作为一种转化/预处理过程的性能，以释放木质纤维素部分的物质，而不是破坏性过程。在 120psi 的压力下，通过氧气存在控制短停留时间和最佳温度的操作条件。湿式氧化下的热水解显著影响了将粪便泥浆转化为有机酸。当反应温度在 150°C-200°C 范围内升高时，乙酸的浓度达到 1778mg/L，在 190°C（60 分钟反应时间）下达到，总有机碳减少，过程液体中的单体减少。另一方面，过程液体中的可溶性 COD 随着反应温度的升高而增加。这些结果为预处理奶牛粪便以提高生化转化产率提供了技术选择的思路。
