Environmental Engineering Department, Faculty of Civil Engineering, Istanbul Technical University, ITU Inşaat Fakültesi, 34469 Maslak, Istanbul, Turkey.
Environ Technol. 2009 Oct;30(11):1169-76. doi: 10.1080/09593330903144041.
This study evaluates the biodegradation kinetics of an integrated dairy wastewater, with the main purpose of defining the experimental basis for modelling of the activated sludge process. Besides conventional characterization, the experiments involved detailed chemical oxygen demand (COD) fractionation and assessment of major kinetic and stoichiometric coefficients, by using respirometric methods. A multi-component model based on the endogenous decay concept was used for the kinetic interpretation. The results of conventional analyses and respirometric evaluations together with the assessment of residual components showed that the organic carbon content of the dairy wastewater was mostly soluble and biodegradable. The soluble, slowly biodegradable COD was the major COD fraction, representing around 50% of the total COD. Model calibration of the oxygen uptake rate profiles were consistent and revealed the existence of dual hydrolysis kinetics for soluble and particulate COD components. The hydrolysis rate associated with the main COD component--the soluble, slowly biodegradable COD fraction--was found to be 1.2 d(-1), which is quite low and underlines the role of this COD fraction as the rate-limiting factor for effluent quality. Simulation of process efficiency by the adopted model, calibrated with the experimentally determined parameters, indicated that effective control of the biodegradation of the soluble biodegradable COD components could be done by selection of appropriate values for the sludge age and hydraulic retention time. In this way, the total effluent soluble COD level could be lowered to 30-40 mg L(-1) range, in conformity with effluent limitations.
本研究评估了集成式奶制品废水的生物降解动力学，主要目的是为活性污泥工艺的建模确定实验基础。除了常规特性描述外，实验还涉及详细的化学需氧量（COD）分类和使用呼吸测量法评估主要动力学和化学计量学系数。基于内源衰减概念的多组分模型用于动力学解释。常规分析和呼吸测量评估的结果以及残留成分的评估表明，奶制品废水中的有机碳含量主要是可溶的和可生物降解的。可溶的、缓慢生物可降解的 COD 是主要的 COD 部分，占总 COD 的约 50%。氧气摄取率曲线的模型校准是一致的，并揭示了可溶性和颗粒状 COD 成分的双水解动力学的存在。与主要 COD 成分——可溶的、缓慢生物可降解的 COD 部分——相关的水解速率为 1.2 d(-1)，这相当低，强调了该 COD 部分作为出水质量的限速因素的作用。采用实验确定的参数进行校准的模型对工艺效率的模拟表明，通过选择适当的污泥龄和水力停留时间值，可以有效地控制可生物降解的可溶性 COD 成分的生物降解。这样，总出水可溶性 COD 水平可以降低到 30-40 mg L(-1)范围内，符合出水限制。
