摘要
[目的]本文旨在探究厌氧过程中猪场废水组成与性质的变化,从微观变化分析沼液难于生化处理的深度原因,对猪场废水处理工艺的优化提供针对性的指导意见。[方法]采集猪场实际废水,利用全混式厌氧反应器(CSTR)对其进行厌氧发酵,探究猪场废水厌氧消化过程中的溶解性和颗粒态有机物组成与性质的变化,以评价厌氧消化对猪场废水可生化性的影响。[结果]随着猪场废水厌氧消化时间的延长,沼液水相的比紫外吸光度从初始值0.057提高到0.104L·mg^-1·cm^-1。同时,亲水性有机物比例从初始的69.8%下降到16.2%。三维荧光光谱显示,随着厌氧消化的进行,可溶性有机物中腐殖酸等难降解有机物的特征峰增强,而易降解的蛋白类有机物特征峰明显减弱。不同厌氧时间的猪场沼液无论稀释与否,其颗粒态有机物(以化学需氧量衡量)水解率或溶解率(经12h曝气处理)均较低,仅为-33.3%~28.6%。沼液中颗粒态有机物通过活性污泥吸附絮凝共沉降去除率也较低(-22.5%~19.4%)。[结论]猪场沼液中颗粒态有机物难于降解或靠活性污泥颗粒吸附絮凝共沉降而去除,且沼液中溶解性有机物结构随消化时间的延长趋于稳定,这2种因素是除猪场废水厌氧消化后氨氮含量较高、C/N严重失衡外,导致猪场沼液难以生化处理的另外重要原因。因此,适当缩短厌氧消化时间并在生化单元前端增加深度去除悬浮物(SS)单元是提高沼液后期生化处理效果的重要手段。
[Objectives] In order to provide targeted guidance to optimize swine slurry treatment process,the effect of anaerobic digestion on the composition and properties was explored and the analysis of the microscopic changes was done to obtain the cause of the difficulty to purify anaerobic digested swine slurry by biochemical method.[Methods] Swine slurry was collected and anaerobically digested in continuous stirred tank reactor(CSTR)model for different time. The changes of the composition and properties of anaerobically digested swine slurry were determined to evaluate its biodegradability.[Results] Specific ultraviolet absorbance(SUVA),an index characterizing the degree of aromatization of dissolved organic matters(DOM),was 0.104 L · mg^-1 · cm^-1 for anaerobically digested swine slurry from initial 0.057 L · mg^-1 · cm^-1 for undigested swine slurry. The hydrophilic fraction of DOM was reduced to 16.2% after anaerobic digestion from initial 69.8%. Three- dimensional fluorescence spectroscopy indicated that with the increase of anaerobic digestion time,the characteristic peaks of refractory organic matters such as humic acid-like in DOM increased,while the characteristic peaks of easily degradable protein -like organic substances decreased significantly. Moreover,the solubility of particulate organic matter(as measured by COD)in anaerobically digested swine slurry was obviously low with only -33.3%-28.6% no matter how long it was digested or whether it was diluted or not even if being aerated for 12 hours. In addition,the removal percentage of particulate organic matter in anaerobically digested swine slurry through activated sludge adsorption and flocculation was also low enough with only -22.5%-19.4%.[Conclusions] The presence of particular organic matter and more stable and refractory DOM in anaerobically digested swine slurry are considered to be two other factors responsible for lower biodegradability of organic substance in swine slurry after long-time anaerobic digestion except for the well-known two fac
作者
邵一奇
王电站
颜成
张华生
周立祥
SHAO Yiqi;WANG Dianzhan;YAN Cheng;ZHANG Huasheng;ZHOU Lixiang(College of Resources and Environmental Sciences,Nanjing Agricultural University,Nanjing 210095,China;Nanjing BACT Environmental Solutions Co. Ltd.,Nanjing 211505,China)
出处
《南京农业大学学报》
CAS
CSCD
北大核心
2019年第4期713-720,共8页
Journal of Nanjing Agricultural University
基金
国家自然科学基金项目(21637003)
江苏省农业自主创新项目[CX(17)2024]
