自来水厂污泥斜板浓缩试验研究

对自来水厂污泥进行了斜板浓缩动态试验研究。结果表明：设计浓缩池不但要以固体负荷为设计参数，还应校核其水力负荷；浓缩池进泥浓度对浓缩效果有一定的影响，进泥浓度〈0．12％时，浓缩效果较差；搅拌转速在较大范围内对污泥浓缩效果的影响基本一致，但搅拌速度过低则易造成刮泥不均匀；斜板浓缩池对污泥的浓缩效率明显高于无斜板浓缩池，在斜板间距≤12cm时其浓缩效率比无斜板浓缩池的高1．5倍；污泥性质对浓缩性能影响较大，有机物和铝含量越低，无机物含量越高，污泥颗粒粒径越大，则污泥的浓缩性能越好；土地价格在斜板浓缩池和无斜板浓缩池的经济性比较中非常重要，在用地面积紧张、土地价格高的地区，斜板浓缩池具有技术经济上的优势。     

龙泉山污水厂污泥脱水车间节能降耗的探索

龙泉山污水厂污泥脱水车间在2007、2008、2009年的三年间平均单位污泥耗药量为4.03 kg/tDS。2011年,通过优化集泥池运行方式强化污泥重力浓缩,完成了节能降耗的初次探索,使单位污泥耗药量降至3.04 kg/tDS,较原来降低24.6%。2012年进行了二次探索,通过对集泥池改用穿孔花墙进水、溢流三角堰出水、池型升级改造为斜板沉淀池和引入离心脱水的清液等方式,使单位污泥耗药量降至2.14 kg/tDS,较2011年降低29.6%,节能降耗成果显著。     

阴离子聚丙烯酰胺对净水厂污泥浓缩性影响的试验研究

取净水厂不同处理单元的排泥水进行阴离子聚丙烯酰胺(PAM)投加的小试,并在污泥泵房污泥浓缩及排放环节进行生产性验证。小试结果表明,随着阴离子PAM投加量的增大,排泥水沉降效果提升,含水率有所降低。生产性验证结果表明,污泥泵房储泥池曝气后的泥水中投加0.2 mg/L阴离子PAM溶液后,沉降效果明显变好,沉降速度加快。回流至调节池的上清液浊度降低,作为生产用原水的水质改善,可适当降低后续处理成本。排泥管内污泥的浓缩性提高,可以考虑适当缩短每个排泥管的排泥时间,减少排泥水量,实现节能减排。     

三池交替工艺的污泥分布规律研究

三池交替工艺的污泥分布特性是由其独特的运行方式决定的。通过分析建立了三池交替工艺的污泥推流模型，根据该模型能掌握任一时间的污泥分布状况。在系统的周期运转过程中污泥分布最终会达到稳定状态，并具有周期重现性，边池的平均污泥浓度远高于中间池。模型算例表明，排泥对污泥分布影响甚微，延长主体段时间或者缩短过渡段和沉淀段时间均可以明显改善污泥分布的不均匀性；在计算污泥负荷和排泥量时需采用反应有效系数加以修正。     

水厂高藻期污泥量的确定与调节

依据沉淀池和排水池的排泥规律确定了日排泥水总量,采用物料平衡法、排泥现场测定法、排泥水处理系统参数监测法及公式法确定日总干污泥量.结果表明:排泥水处理系统监测法操作容易、设备简单且数据可靠.通过污泥量的确定,可调节排泥规律和排泥水处理系统的流量及浓度,并可降低排泥水对系统的冲击负荷,使水厂在高温高藻期达到稳定运行.     

上海临江水厂污泥脱水系统的运行优化

2011年临江水厂污泥脱水系统进行了调试、运行,厂内所有生产废水全部进入污泥处理系统,处理后出水水质达到《上海市污水综合排放标准》(DB 31/199—2009)的一级标准。对浓缩池、压滤机等关键设备设施的运行进行优化,调整了部分运行参数和自控程序,压滤部分新增投加PAM替代石灰进行污泥调质。优化后浓缩池上清液浊度及排泥浓度均有所改善,压滤机脱水后泥饼含固率明显上升,降低了污泥体积及后续处理成本。     

应用旋流分离器去除自来水厂泥水中的煤和炭

北京市自来水集团某自来水厂具有较完善的反冲洗废水回用、污泥处理系统,其中有两座生产废水回用水池,收集煤滤池反冲洗排水、活性炭滤池反冲洗排水以及水厂污泥处理单元中的排泥池和浓缩池上清液。回用的生产废水经过沉淀后,上清液直接回用到水处理单元前端再处理,其底部沉淀的泥水被送到污泥处理系统中的排泥池。     

LSP＆PNR污泥减量工艺的污泥特性研究

通过研究分析LSP&PNR污泥减量新工艺在不排泥与排泥两种运行条件下的污泥特性和除污效果,结果发现:系统不排泥运行时,COD去除效果逐渐变差,最终导致出水不达标,且污泥活性逐渐降低;当污泥龄控制在50 d时,系统的沉降性能不是特别理想但并无污泥膨胀之忧,且系统中单位体积污泥总耗氧速率T-SOUR较高,均值为66.1 mgO2/(L·h),表明系统污泥整体活性很强.     

自来水厂排泥水处理技术的若干问题

探讨了自来水厂排泥水处理技术的若干问题,诸如正确确定自来水厂的污泥干固体产量的方法,减少自来水厂沉淀池的排泥水水量的措施,设置污泥调蓄均衡池的必要性等,指出自来水厂的排泥水处理工作应从对具体水厂的排泥水水质特性分析出发,注意自来水厂污泥和污水厂污泥之间的本质差别。     

净水厂的污泥处理设计及运行控制

以象山滨海净水厂污泥处理系统为例,介绍了净水厂污泥处理的工艺流程。阐述了回流水池、排泥池、浓缩池、污泥提升泵房和脱水机房等主要构筑物的作用及设备配置情况,依次描述了各设备的启动、运行频次等运行控制设置。最后,根据1 a的运行情况,总结出配泥井堵塞、浮动槽倾斜、脱水污泥浓度控制及回流泵启动液位调整等问题及解决措施。生产实践证明,该污泥处理系统的设计和运行控制达到了预期效果。     

逆向流斜板沉降器的改进设计及其性能研究

介绍了一种改进型逆向流斜板沉降器的设计原理，通过试验，与相同几何尺寸的传统型逆向流斜板沉降器的固液分离性能进行了比较。结果表明，在处理流量为0．2m^3／h和0．25m^3／h的正常水力负荷下，改进型斜板沉降器的整体出水浊度较传统型的分别低39．95％和47、52％，且其各出水分区的水质较传统型的均匀、稳定；在处理流量为0、35m^3／h的超常水力负荷下，传统型斜板沉降器不能正常运行，而改进型斜板沉降器可正常运行；在临界流量下，改进型斜板沉降器的表面负荷较传统型的高出28．13％。斜板沉降器的改进设计解决了其在工程应用中出现的排泥困难、出水水质不均匀、抗冲击负荷能力差等问题。     

微絮凝拦截沉淀处理低温低浊水

拦截沉淀池是根据水中微絮体的凝聚沉淀特性,用一种特殊材料设计构造的以接触凝聚和拦截沉淀为主要功能的新型沉淀池。以北京市第九水厂原水为主要对象,研究了拦截沉淀对低温低浊水的处理效果,并与传统的平流及斜板沉淀池进行了对比。结果表明,拦截沉淀池有优异的拦截聚沉和对水质变化的适应能力,处理效果要明显优于平流沉淀池而接近于斜板沉淀池,有很好的开发及应用前景。     

微絮凝拦截沉淀处理低温低浊水

拦截沉淀池是根据中微絮体的凝聚沉淀特性,用一种特殊材料设计构造的以接触凝聚和拦截沉淀为主要功能的新型沉淀池。以北京市第九水原水为主要对象,研究了拦截沉淀对低 氏浊水的处理效果,并与传统的平流以沉淀池进行了对比。结果表明,拦截没淀池有优异的拦截聚沉和对水质变化的适应能力,处理效果要明显优于平流沉淀池而接近于斜板沉淀池,有很好的开发及应用前景。     

Effect of sludge retention time on inclined plate function,treatment performance and sludge characteristics of inclined plate membrane bioreactors treating municipal wastewater

Two identical bench scale inclined plate membrane bioreactors (ip‐MBRs) were operated for the treatment of real municipal wastewater for 1 year. Sludge retention time (SRT) was varied over the course of operation to investigate the effects on inclined plate function, treatment performance and sludge characteristic. Removal rates of chemical oxygen demand and ammonia over 90% and of total nitrogen (TN) more than 70% were achieved when ip‐MBRs were operated under SRTs between infinite and 40 days while short SRT (20 days) negatively affected TN removal. When the sludge concentration in anoxic tank exceeded 15 g/L, the failure of the inclined plate function was observed, resulting in no difference in sludge concentrations between aerobic and anoxic tanks. To avoid severe effects on inclined plate function and treatment performance, an SRT range of 40–80 days was recommended for ip‐MBRs. Moreover, sludge floc size under prolonged SRT became smaller than that under short SRT due to increased attrition among the sludge floc particles caused by strong aeration needed for keeping a sufficient dissolved oxygen level.     

Design and operational charts for complete mixing activated sludge systems

This paper provides charts enabling the derivation of design and operational procedures for an activated sludge waste water treatment system including the final settler. These charts are based on a mathematical model including Monod relationships describing the microbial growth and the substrate removal in the aerator, while sedimentation in the final settler is assumed to follow the limiting flux theory. Charts represent the minimum required settler area, insuring that given effluent standards will be met, as a function of either the hydraulic retention time or the recycle rate. Most design and operational characteristics of the activated sludge system can be read directly on the charts, while a simple equation is provided for the sludge wasting rate.Operational procedures under constant or variable inflow conditions are first derived from the charts. It is concluded that operational policies including a constant recycle sludge concentration are especially attractive in response to various types of influent variations. Such policies allow one to maintain either the effluent substrate concentration or the recycle flow rate at the same level in most situations. Furthermore, the required settler area remains reasonably small. Large aerators provide considerable operational flexibility and appear to be required when hydraulic overloads are expected.The charts allow one to design the activated sludge system in such a way that expected overload conditions can be overcome. Least-cost design is briefly studied through simplified cost functions. This allows derivation of the best compromise between sufficient operational flexibility and least-cost design, leading to the “optimal overdesign” of the system.Parameter variability has a significant influence on the charts. Hence, correct determination of the model parameters is required before calibrating and using the charts.     

Effect of low ORP in anoxic sludge zone on excess sludge production in oxic-settling-anoxic activated sludge process

This paper studied the effect of oxidation-reduction potential (ORP) in the anoxic sludge zone on the excess sludge production in the oxic-settling-anoxic process (OSA process), a modified activated sludge process. Two pilot-scale activated sludge systems were employed in this study: (1) an OSA process that was modified from a conventional activated sludge process by inserting a sludge holding tank or namely the "anoxic" tank in the sludge return line; and (2) a conventional process used as the reference system. Each was composed of a membrane bioreactor to serve the aeration tank and solid/liquid separator. Both systems were operated with synthetic wastewater for 9 months. During the operation, the OSA system was operated with different ORP levels (+100 to -250 mV) in its anoxic tank. It has been confirmed that the OSA system produced much less excess sludge than the reference system. A lower ORP level than +100 mV in the anoxic tank is in favor of the excess sludge reduction. When the ORP level decreased from +100 to -250 mV the sludge reduction efficiency was increased from 23% to 58%. It has also been found that the OSA system performed better than the reference system with respect to the chemical oxygen demand removal efficiency and sludge settleability. The OSA process may present a potential low-cost solution to the excess sludge problem in an activated sludge process because addition of a sludge holding tank is only needed.     

DYNAMIC MODELLING OF SEDIMENTATION IN THE ACTIVATED SLUDGE PROCESS

Secondary sedimentation plays a fundamental role in biological wastewater treatment processes where activated sludges are used. In addition to water clarification and sludge compaction, the secondary settler is used as a dynamic storage for the biomass in the system. This role is important for process control since displacing sludge from the settler to the oxidation tank is the main way to adjust process conditions in the short time-scale. The scope of this paper is to present a model for the time-varying behaviour of the total activated mass, taking into account the coupling between the aeration tank and the secondary settler. Numerical simulations show that the model can reproduce any relevant feature of the real system and can be used in control strategy design for sludge management.     

吸附曝气塔滤工艺处理染织废水

通过活性污泥与生物膜的协同作用．强化了传质过程，避免了难降解有机物在生物膜上的积累，刺激了膜上微生物的利用溶解有机物的活性，具有污泥负荷高，有机物去除率高，占地少．耗电省、运行安全可靠的优点．     

南方地区典型水厂排泥水水质特性研究

选择南方某城市3座具有典型自来水和排泥水处理工艺的水厂,从物理、化学、生物安全性三个方面对排泥水、砂滤和炭滤池反冲洗水、排水池和排泥池上清液的水质特征进行了系统研究,并考察了原水水质、工艺选择和控制、排泥水收集和处理模式等因素对排泥水水质的影响。