游离氨调理污泥厌氧消化优化产甲烷过程与强化有机物释放

针对污泥减量和资源化目标，采用游离氨调理浓缩污泥，评估了有机物释放和产甲烷促进效果。结果表明，浓缩污泥经游离氨(200~800 mg·L^-1，24 h)调理，累积产甲烷量和产甲烷潜势分别提高了34.6%、23.3%。不同于高能耗预处理的彻底溶胞破壁，游离氨调理主要强化了小分子有机物穿胞透壁的释放，较对照组提升SCOD浓度5.19%~23.81%、溶解性蛋白质浓度1.47%~14.55%、溶解性多糖浓度-0.64%~14.63%。后续厌氧消化过程中VS水解明显，溶解性SCOD的降解提升34.2%~62.24%。基于三维荧光光谱(3D-EEM)的平行因子法(PARAFAC)分析结果表明，可利用程度较高的色氨酸类物质荧光组分明显提高，表明游离氨强化了生物难降解性有机物转化和可降解性有机物的降解。在此过程中，厌氧消化第一次产气高峰(0~5 d)以及第二次产气高峰(9~12 d)的速率分别提升21.04%、120.39%。上述结果表明，游离氨调理强化了浓缩污泥中有机物的初期释放和后期转化，从而提升了甲烷产率，是一种绿色低耗的污泥资源化技术。

Free ammonia conditioning promoted micro-molecule organics release and methanogenesis of thickened sludge

To facilitate reduction and resource recovery from excess sludge, thickened sludge was conditioned with free ammonia conditioning (200-800 mg·L^-1, 24 h). The results demonstrate that the methanogenesis was promoted by release of micro-molecules organics through the cell membrane. The accumulated methane production and biochemical methane potential was promoted by 34.6% and 23.3%, respectively. The soluble organic matters was released as soluble chemical oxygen demand (SCOD), including soluble protein, and soluble carbohydrate which were promoted by 5.19%-23.81%, 1.47%-14.55%, and -0.64%-14.63%, respectively. Hydrolysis of the released organic matters was further enhanced by 34.2%-62.24% in form of SCOD. The first methane production peak (0-5 d) and the secondary peak (9-12 d) was improved by 21.04%, 120.39%, respectively. Parallel factor analysis (PARAFAC) based on 3-D fluorescence spectroscopy (3D-EEM) indicated that the refractory organic matter converted to biodegradable tryptophan. The above results show that free ammonia conditioning strengthens the initial release and later conversion of organic matter in the thickened sludge, thereby improving the methane yield, which is a green and low-consumption sludge resource technology.