Department of Hydraulic and Environmental Engineering, Polytechnic School, University of Sao Paulo, Brazil.
J Environ Manage. 2018 Jun 1;215:283-293. doi: 10.1016/j.jenvman.2018.03.072.
An emerging practice for water treatment plant (WTP) sludge is its disposal in wastewater treatment plants (WWTP), an alternative that does not require the installation of sludge treatment facilities in the WTP. This practice can cause both positive and negative impacts in the WWTP processes since the WTP sludge does not have the same characteristics as domestic wastewater. This issue gives plenty of information in laboratory and pilot scales, but lacks data from full-scale studies. The main purpose of this paper is to study the impact of disposing sludge from the Rio Grande conventional WTP into the ABC WWTP, an activated sludge process facility. Both plants are located in São Paulo, Brazil, and are full-scale facilities. The WTP volumetric flow rate (4.5 m³/s) is almost three times that of WWTP (1.6 m³/s). The data used in this study came from monitoring the processes at both plants. The WWTP liquid phase treatment analysis included the variables BOD, COD, TSS, VSS, ammonia, total nitrogen, phosphorus and iron, measured at the inlet, primary effluent, mixed liquor, and effluent. For the WWTP solids treatment, the parameters tested were total and volatile solids. The performance of the WWTP process was analyzed with and without sludge addition: 'without sludge' in years 2005 and 2006 and 'with sludge' from January 2007 to March 2008. During the second period, the WTP sludge addition increased the WWTP removal efficiencies for solids (93%-96%), organic matter (92%-94% for BOD) and phosphorus (52%-88%), when compared to the period 'without sludge'. These improvements can be explained by higher feed concentrations combined to same or lower effluent concentrations in the 'with sludge' period. No critical negative impacts occurred in the sludge treatment facilities, since the treatment units absorbed the extra solids load from the WTP sludge.
一种新兴的水处理厂（WTP）污泥处理方法是将其在废水处理厂（WWTP）中处置，这是一种不需要在 WTP 中安装污泥处理设施的替代方法。这种做法会对 WWTP 工艺产生正反两方面的影响，因为 WTP 污泥与生活污水的特性不同。这个问题在实验室和中试规模上提供了大量信息，但缺乏来自全规模研究的数据。本文的主要目的是研究将里奥格兰德常规 WTP 的污泥排入 ABC WWTP 的影响，ABC WWTP 是一个活性污泥工艺设施。这两个工厂都位于巴西圣保罗，都是全规模工厂。WTP 的体积流量（4.5m³/s）几乎是 WWTP（1.6m³/s）的三倍。本研究使用的数据来自两个工厂的过程监测。WWTP 液相处理分析包括在入口、初级出水、混合液和出水处测量的 BOD、COD、TSS、VSS、氨、总氮、磷和铁等变量。对于 WWTP 固体处理，测试的参数是总固体和挥发性固体。在添加和不添加污泥的情况下分析了 WWTP 工艺的性能：2005 年和 2006 年的“无污泥”和 2007 年 1 月至 2008 年 3 月的“有污泥”。在第二个时期，与“无污泥”时期相比，WTP 污泥的添加提高了 WWTP 对固体（93%-96%）、有机物（BOD 的 92%-94%）和磷（52%-88%）的去除效率。这些改进可以通过较高的进料浓度与“有污泥”时期相同或较低的出水浓度来解释。污泥处理设施没有发生严重的负面影响，因为处理单元吸收了 WTP 污泥带来的额外固体负荷。
