排泥水处理技术在闵行一水厂的应用

通过对污泥沉降特性研究 ,闵行一水厂排泥水处理采用收集、浓缩、平衡、投加聚丙烯酰胺 (PAM )、离心机固液分离的工艺流程。浓缩池上清液能达标排放 ,离心机分离水的泥饼含固率≥4 0 % ,PAM加注率 0 8～ 1 5kg/t干泥。研究表明 ,该工艺可作为黄浦江水系水厂排泥水处理工艺设计依据     

高效固液分离技术处理给水厂排泥水的中试研究

以天津杨柳青水厂排泥水为处理对象,利用高效固液分离技术进行处理规模为2.04～5.44 m3/h的中试研究,确定了在管式反应器与静态混合器不同混合反应条件下的工艺控制参数.试验结果表明,利用高效固液分离技术处理给水厂排泥水是切实可行的,系统连续运行的稳定性高,稳定运行时的出水浊度一般低于5 NTU.进水SS在300 mg/L时,确定的适宜工艺控制参数为:PAC投量6～11 mg/L,PAM投量0.97～1.22 mg/L,机械搅拌转速为8～12 r/min,最大上升流速可达65～70 cm/min;前置混合条件采用静态混合器-管式反应器时的处理效果较佳.     

自来水厂排泥水处理浓缩工艺运行优化研究

X水厂采用传统的排泥水处理工艺,计划将浓缩池上清液用于景观河道的补充用水,原设计出水水质与实际目标有一定差异。为进一步提升浓缩池出水水质,该厂采用加药再絮凝方式进行小试,发现降浊最佳工艺条件为加硫酸铝25 mg/L,慢速搅拌。在此基础上进行了再混凝沉淀中试,发现加药混合再絮凝与加药混合不絮凝降浊效果相似并优于自然沉降。并通过生产性试验,进一步验证了在浓缩池增加加药及混凝,可以明显的改善除浊效果,提升出水水质。同时针对排泥水运营精细化管理,提高水质、稳定排泥等方面提出建议。     

月浦水厂排泥水浓缩处理工艺初步研究

对上海市月浦水厂的沉淀池排泥水进行浓缩工艺研究 ,旨在为今后建设给水厂排泥水浓缩处理设施提供设计和运行的必要基础资料。试验结果表明 ,斜板浓缩池对给水厂排泥水可以产生良好的浓缩效果。浓缩后的泥水含固率 >3% ,上清液SS <15 0mg/L。     

苏州某自来水厂排泥水处理系统运行优化试验研究

为提升自来水厂排泥水处理系统运行效率,降低水厂耗水率,开展排泥水预处理试验和浓缩池动态模型试验.结果表明:与预处理前相比,投加0.3 mg/L阳离子型PAM,可以使排泥水中粒径小于5μm的颗粒占比减少22％,粒径大于10μm的颗粒占比提高110％,颗粒沉降速率提高20％,上清液浊度下降75％.根据浓缩池动态模型试验结果...     

造粒流化床浓缩技术处理给水厂排泥水的中试研究

以南方某给水厂排泥水为处理对象,利用造粒流化床污泥浓缩工艺进行了处理规模为 1-2．5 m3／h的中试研究。研究结果表明,对于排泥水有机物、藻类含量高的南方水厂而言,采用一 体化造粒流化床浓缩工艺进行处理是切实可行的,且具有处理效率高、出泥含水率低、脱水性能好、 出水浊度低等特点;中试条件下,流化床水流上升速度可达38-50 cm／min,最佳搅拌转速为 5 r／min,PAM药耗比普通重力浓缩-调质工艺节省25％-40％,污泥含水率可从99％降至95％- 97％。并通过试验确定了相关工艺参数。     

吹填泥浆的混凝沉降特性试验

为解决水力吹填泥浆自由沉降所需时间较长,退水排放会带走大量淤泥,以及吹填土地基自然固结时间长等问题,向泥水混合液分别投加聚合氯化铝(PAC)和聚丙烯酰胺(PAM),搅拌静置沉淀后测定混合液剩余浊度、剩余固体悬浮物质量浓度(SS)及泥水界面高度,考察其混凝沉降性能。试验结果表明,投加混凝剂能在一定程度上加速吹填泥浆的沉降分离,提高出水水质。随着PAC和PAM投加量的增加,混合液剩余浊度和剩余SS值均呈现先降低后升高的趋势,而泥水界面高度基本保持不变。当PAC投加量为360mg／L时,混合液剩余浊度和剩余SS达到最小值,分别为287.4和1.45g／L;当PAM投加量为2.8mg／L时,混合液剩余浊度和剩余SS最小,分别为752.7和2.83g／L。     

新型中置式高密度沉淀池优化投药试验研究

通过小试和生产性试验对新型中置式高密度沉淀池的投药系统(包括回流污泥、混凝剂及助凝剂PAM的投加)进行了详细研究.小试研究表明回流污泥和混凝剂投加量的增大降低了上清液浊度,PAM的投加略微降低了上清液出水浊度,但影响不大.生产性试验研究结果表明,实际生产运行中可灵活利用回流污泥来提高絮凝效果,在合理的范围内回流污泥投加量越大,絮凝效果越好;沉淀池随着混凝剂投加量的增大,出水浊度逐渐降低,同时,不同的回流污泥投加量条件下混凝剂投加对沉淀池出水浊度的影响表现出不同特性;增大PAM投加量对直接提高沉淀池的絮凝效果以及降低出水浊度的贡献不明显,PAM投加量的增大间接引起回流污泥投加量变大是导致出水浊度变小的原因.     

河道污水污泥性能试验研究

河道污水采取化学一级强化处理工艺所产生的污泥沉降性差,通过污泥性能的小试和生产试验结果表明,投加PAM对污泥助凝有明显效果,且阳离子PAM投加效果比阴离子PAM效果好.当阳离子PAM投加量3 mg/g时效果最佳.生产试验证明,在污泥浓缩池投加PAM能有效改善污泥浓缩效果.     

广东某市自来水厂投加PAM对出厂水效果影响研究

该文主要介绍了广东某市自来水厂加药系统同时投加聚合氯化铝(PAC)和聚丙烯酰胺(PAM)与单一投加聚合氯化铝(PAC)对水厂出水水质的影响效果,以出水浊度及耗氧量为评价指标,通过11、12月份的出水水质连续性检测,对比研究水厂增加了PAM投加后出厂水的影响效果,结果显示:在PAM投加量与原水的比例为0.15 ppm,PAC投加量与原水的比例为3 ppm的条件下,水厂出水效果较好,且运行成本较低。     

增效结团流化床处理春季低浊水的中试研究

以水库春季低浊水为处理对象,采用增效结团流化床工艺进行了中试研究。试验结果表明,利用增效结团流化床工艺处理水库低浊水是切实可行的,具有系统运行稳定性高,出水水质好等特点,而良好的污泥回流是系统高效稳定运行的前提。控制上升流速为20m/h时,通过优化得出适宜的工艺参数:混凝剂聚氯化铝(PAC)投量为11 mg/L左右,助凝剂(PAM)投量为0.25～0.30mg/L,污泥回流比为3%,机械搅拌转速为6r/min。在此条件下,出水浊度可控制在1.0NTU以下。     

微砂增效结团絮凝技术处理低浊高藻水的中试研究

针对西安市汤峪水库夏季水质特点和处理要求,提出并采用微砂增效结团絮凝工艺对该原水处理进行中试研究.微砂增效结团絮凝技术是将微砂增效与结团絮凝有机组合的新型水处理工艺.试验结果表明,利用微砂增效结团絮凝技术处理汤峪水库低浊高藻水是切实可行的,系统具有运行稳定性高、出水水质好等特点,且处理效率明显高于采用回流污泥的增效澄清技术.微砂增效结团絮凝工艺能够有效降低出水浊度和CODMn;当微砂投量0.5 g/L时的过程控制参数为PAC投量15mg/L,PAM投量0.4 mg/L,机械搅拌转速8 r/min,上升流速达35 m/h时,藻类去除率可达80％,CODMn去除率达40％,浊度可控制在1.5 NTU以下.     

Pilot study of a fluidized-pellet-bed technique for simultaneous solid/liquid separation and sludge thickening in a sewage treatment plant.

A fluidized-pellet-bed separator with movable sludge hoppers was applied in pilot scale for the separation and thickening of activated sludge mixture liquid. Under the condition of suspension SS around 4,000 mg/L, polymer (CJX103, cationic, MW 5 x 10(6)) dose at a dry solid ratio of 0.003 and upward flow rate at 5.4 m/hr, the fluidized pellet bed performed solid/liquid separation and sludge thickening well. The SS concentration of the treated water was about 5 mg/L on average and the moisture content of the sludge after screening for 5 min was less than 94%, which is much lower than that after conventional settling and thickening and easy to be finally disposed. At a higher upward flow rate of 7.2 m/hr, similar results could also be obtained but higher polymer dose (solid ratio of 0.004) was required. The morphological characteristics and density-size relationship of the granular particles formed in the fluidized pellet bed were also investigated by image analysis and settling velocity measurement of individual particles. The two-dimensional fractal dimension was evaluated to be 1.6-1.8, showing a good quasi-spherical morphology of the granular particles with their density much higher than the conventional flocs. The results of the pilot study indicate a possible way to innovate the conventional secondary settling and gravitational thickening processes for solid/liquid separation and sludge handling, especially for small scale wastewater treatment plants to reach the goal of space saving and higher treatment efficiency.     

Improvement of the thickening and dewatering characteristics of activated sludge by electroflotation (EF).

The performances of electroflotation (EF) on the thickening of activated sludge were investigated using laboratory scale batch flotation reactors. Four activated sludges including bulking sludges were tested. After 30 minutes of EF operation, 57-84% of sludge volume reduction could be achieved by EF, while only about 1.5-14% could be obtained by gravity thickening for the same period. After thickening the effluent water quality in terms of TCOD, SS, and turbidity was improved by EF operation for all sludge samples. In addition, the EF thickened sludge showed much better dewaterability both in SRF and cake solid content. It is induced that the air bubbles entrapped in the thickened sludge play a key role in the observed dewaterbility improvement.     

净水厂生产排泥水处理工艺研究与设计

通过对净水厂生产排泥水的产生和水质特性进行分析,确定沉淀池排泥水和滤池反冲洗废水为净水厂排泥水的主要组成,结合设计干泥量的计算确定排泥水处理规模,在分析排泥水处理系统工艺流程布置特点的基础上对排泥水收集、调节、浓缩和脱水工艺进行分析,并对其中排水池、排泥池、浓缩池、平衡池、脱水工艺和场地布置的设计要点进行总结。     

Sludge thickening performance of mesh filtration process.

Small-scale wastewater treatment facilities play an important role in improving the aquatic environment in many countries. Although sludge treatment is essential for overall wastewater treatment, it is difficult for small-scale facilities to use mechanical equipment or other facilities. As the first step of the sludge treatment, it is important to develop a convenient sludge thickening process for small-scale facilities. In this work, we examined the sludge thickening performance of a mesh filtration system: the mesh opening sizes of 100-500 microm, and the sludge (3,000-9,000 mg-SS/L) was obtained from a domestic wastewater treatment facility. The filtration was carried out only under the hydraulic pressure between the water level and the effluent port connected to the mesh filter module. The sludge reduction rates were in the range of 85-95% for 6-7 h; the initial filtration rate was very high, but the rate decreased with a decrease in hydraulic pressure due to the reduction of the water level in the vessel. In addition, the effluents (passed through the mesh) contained very low SS and could be directly discharged into the environment.     

Analysing sludge balance in activated sludge systems with a novel mass transport model

In activated sludge systems the mechanically treated wastewater is biologically cleaned by biomass (activated sludge). The basic requirement of an efficient biological wastewater treatment is to have as a high biomass concentration in the biological reactor (BR) as possible. The activated sludge balance in activated sludge systems is controlled by the settling, thickening, scraper mechanism in the secondary settling tank (SST) and sludge returning. These processes aim at keeping maximum sludge mass in the BR and minimum sludge mass in the SST even in peak flow events (storm water flow). It can be, however, only reached by a high SST performance. The main physical processes and boundary conditions such as inhomogeneous turbulent flow, geometrical features of the SST, wastewater treatment plant (WWTP) load, return sludge flow, sludge volume index etc. all influence settling thickening and sludge returning. In the paper a novel mass transport model of an activated sludge system is presented which involves a 2-dimensional SST model coupled with a mixed reactor model of the biological reactor. It makes possible to investigate different sludge returning strategies and their influence on the sludge balance of the investigated activated sludge system, furthermore, the processes determining the flow and concentration patterns in the SST. The paper gives an overview on the first promising model results of a prevailing peak flow event investigation at the WWTP of Graz.     

Application of the flotation process to thicken the sludge from a DAF plant.

Dissolved air flotation (DAF) was evaluated for thickening of the sludges from a water treatment plant which uses DAF. Solid flux theory for gravity thickening was applied to the solid flux of DAF sludge. The higher the polymer dosage, at fixed solid concentration, the greater the rising velocity becomes. When applied with solid flux equations, a similar relationship to that of gravity thickening has been found. However, the values were much higher than in gravity thickening, because both the inflow solid concentration and the floating velocity were higher than for settled sludge. With this result, the proper dosage of polymer could be derived from the relationship between total solid flux and withdrawal velocity of DAF sludge.