微絮凝直接过滤工艺处理微污染矿井水的研究

采用微絮凝直接过滤工艺对阜新矿区的微污染矿井水进行处理,对相关参数进行了优化并研究了过滤特征。试验结果得出:絮凝剂聚合氯化铝最佳投药量和絮凝时间分别为2～4 mg/L和3～4 min,最优滤速为10～14m/h,此时过滤周期可达到30～40 h,出水浊度和悬浮物浓度可分别达到1 NTU和5 mg/L以下,符合回用水标准。     

初滤水回用途径探索

新修编的《室外给水设计规范》(GB 50014-2006)指出,从提高滤后水卫生安全性考虑,初滤水宜排除或采取其他控制措施.初滤水排放时间约30 min,排放的水量占水厂水量的1%～2%,因此,回收利用初滤水,或采取措施提高初滤水水质直接回收利用,是节能降耗的一项重要措施.提出了回收利用初滤水的途径和措施,如采用降低初滤时段滤速,减小或消除滤速突变等方法.     

微污染水源水的强化絮凝处理

利用微涡旋控制理论对南方某水厂传统絮凝网格进行了强化絮凝改造。运行结果表明,基于对剪切力与粘性力控制的强化絮凝网格处理微污染水源水具有一定优势:絮凝能耗小,出水矾花密实(分形系数大),矾花粒径大,对应的沉后水浊度降低0.1～0.3 NTU,沉后水、砂滤水藻类和有机物的去除率分别增加2％～5％。     

郑州段南水北调水微絮凝-直接过滤试验研究

以南水北调水为原水、聚合氯化铝(PAC)为混凝剂,进行微絮凝-直接过滤的中试试验。运用浊度仪、紫外分光光度计等对过滤前后水的浊度、UV_(254)、COD_(Mn)、NH_3-N和残余铝浓度进行检测,以确定PAC的最佳投加量,同时观察不同PAC投加量下滤柱内水头上涨幅度随时间的变化情况。结果表明:南水北调水河南受水区微絮凝-直接过滤工艺的PAC最佳投加量为24 mg/L,此时对浊度、COD_(Mn)、UV_(254)和NH_3-N的去除率分别为45.0%、59.3%、28.1%、80.0%,残余铝浓度未超标;该PAC投加量下,滤柱的反冲周期缩短为9 h,且滤柱内水头增长幅度与过滤时间呈线性关系。     

颗粒计数法用于给水厂滤池运行的研究

以上海地区的两种原水和不同过滤工艺为例,采用生产性试验与模拟柱试验相结合的手段,探讨了颗粒计数法与浊度联合用于过滤环节运行管理和质量控制的可行性。研究结果表明,滤料层不同深度出水的颗粒数超过50粒/mL的穿透时间与滤速之间存在正相关性;滤后水的颗粒物数量变化比浊度更灵敏地反映滤池运行状况;初滤水存在颗粒短时穿透现象,且以小于10μm的颗粒为主,为防止"两虫"所引起的风险,生产性运行时需采取适当的调控措施。利用颗粒物对数去除率指标可以综合判断滤池的运行状况,有助于提高滤池的工作效能。     

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.     

微絮凝-大梯度磁滤工艺对消毒副产物前驱物控制的研究

以珠江水为原水,利用微絮凝-大梯度磁滤工艺对水中消毒副产物前驱物进行处理,研究工艺的磁场强度和磁滤速度的变化对消毒副产物生成势(THMFP)和UV_(254)的去除效果影响。研究发现,去除THMFP以去除三氯甲烷生成势为主;THMFP的去除效率随着磁场强度的升高或滤速的降低而升高,在磁场强度为0.23T时达到最高为47.83%,磁滤速度为6~8m/h时,去除率稳定在46%左右;UV_(254)的去除效果受滤速的影响较大,滤速从6 m/h提高到16 m/h时,去除率从57.56%下降到39.58%,而磁场强度的变化对UV_(254)的去除效率影响较小,去除率稳定在46.0%~50.7%。     

连续式砂滤器过滤技术试验研究

文章对影响内循环连续式砂滤器工作效率的滤池工作参数进行研究 ,提出设备运行的关键工作参数 :滤料粒径df=0 7～1 0mm、Df =0 6m、υf <12m h、提砂管内气水比 9～ 11、ωz =2～ 4mm min。同时试验对滤前工作条件进行研究 ,认为滤前的混合搅拌强度应保证在 5 0 0 0～ 10 0 0 0 ;当进水浊度低时滤前微絮凝反应时间不小于 3min ,当进水浊度较高时 ,滤前微絮凝时间不小于 7min ,这些设备运行关键参数的提出为这种新型一体化过滤装置的开发应用创造了条件     

板间距对电絮凝处理微污染水的影响

电絮凝作为一种具有广泛应用前景的低廉高效污水处理技术,已经被证明在工业废水、生活污水等污染严重的水体处理上具有显著效果,但是目前对于电絮凝净化微污染水的相关研究较少。通过对电絮凝分批处理河水的实验研究,分析电絮凝方法处理微污染水的可行性,讨论极板间距的改变对电絮凝处理效果的影响。结果表明,电絮凝处理技术可以用于微污染水净化中,在电流密度为17.75 A/m2、极板间距为1.5 cm的条件下,反应30 min时,色度去除率为73.76%,浊度去除率为76.00%,悬浮固体去除率为85.71%,化学需氧量去除率为42.86%,总磷去除率为61.36%。在电絮凝反应中,极板间距对于微污染水的色度、浊度、悬浮固体和总磷去除效果具有明显的影响。     

粕滤慢滤技术在西北村镇集雨窖水处理中的应用研究

针对西北村镇集雨窖水污染现状,采用粗滤慢滤组合净水工艺进行了现场试验研究.通过自然挂膜确定了膜的生物稳定期,并对其影响因素进行了分析.结果表明:粗滤慢滤小型净水装置能有效地处理西北村镇集雨窖水.对窖水的浊度、有机物、氨氮及微生物学指标有良好的去除效果.在粗滤慢滤装置滤速控制在0.1 m/h的情况下,生物膜生长期为40～50 d.在生物膜形成之后,出水氨氮平均0.285 mg/L,氨氮去除率最高达78.35％;出水CODMn平均2.27 mg/L,CODMn去除率最高达到61.58％.出水浊度平均0.56 NTU,浊度去除率最高达到98.99％.该净水技术工艺简单,无需投药,操作管理方便,适用于西北村镇等以户为单位的分散式窖水处理.     

Particle and microorganism removal in floating plastic media coupled with microfiltration membrane for surface water treatment.

Floating plastic media followed by hollow fiber microfiltration membrane was applied for surface water treatment. The performance of the system in terms of particle and microorganisms was investigated. The floating filter was examined at different filtration rates of 5, 10 and 15 m3/m2 x h. Treated water was then fed into a microfiltration unit where different filtration rates were examined at 0.6, 1.0 and 1.4 m3/m2 x d. It was found that polyaluminum chloride was the best coagulant for the removal of particle, algae and coliform bacteria. Average turbidity in treated water from the floating plastic media filter was 3.3, 12.2 and 15.5 NTU for raw water of 80 NTU and 12.9, 11.7 and 31.2 NTU for raw water of 160 NTU after 6 hours at the filtration rates of 5, 10 and 15 m3/m2 x h, respectively. The microfiltration unit could further reduce the turbidity to 0.2-0.5 NTU with low transmembrane pressure development of 0.3-3.7 kPa. Microfiltration membrane could retain most of algae and coliform bacteria remaining in the effluent from the pretreatment unit. It was found that at higher turbidity, algae and coliform bacteria removal efficiencies were achieved at lower filtration rate of the system of 5 m3/m2 x h whereas a higher filtration rate of 15 m3/m2 x h yielded better coliphage removal.     

Application of the flexible fiber filter module (3FM) filter to sea water filtration.

The new 3FM filter (Flexible Fiber Filter Module), implementing very fine nylon fibers as filtration media was tested at pilot scale for the first time on sea water. The objective was to improve the quality of raw sea water to produce water for injection into offshore wells for extraction purposes on oil-bearing fields. Particles larger than 5 microm must be removed from the water of injection to avoid clogging at the point of injection into the porous rock. The purpose of the tests carried out over several months at Palavas Les Flots (France) was to specify the optimal operating conditions of the 3FM filter. Various coagulants and combinations of reagents were tested at velocities ranging between 50 and 200 m(3)/m(2)/h (ground filtration velocity). On raw sea water of about 1 NTU turbidity and at velocities of 100 m(3)/m(2)/h, the filtered water contained about 300 particles per mL larger than 1 microm, and less than 15 particles larger than 5 microm per mL. The filter runs range from one hour to few hours, variable according to the raw water turbidity, the reagent dosing rate and the filtration velocity. Backwashes, a succession of air scours at high air flow rates combined with water phases, the total duration of which did not exceed 1 minute, were shown to be efficient during the three months testing period. 3FM filter performance was promising for many other possible applications.     

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。     

Efficiencies of residual organic pollutants removal from secondary effluent by switching of coagulation- air flotation -filtration processes.

It is an essential task to remove the residual organic pollutants (ROP) from secondary effluent of a Wastewater Treatment Plant (WWTP) in wastewater reclamation and reuse processes. Four different compared flow schemes would be achieved for further purification of the secondary effluent by switching of different valves. In order to mainly remove non-biodegradable residual organic pollutants under various operating conditions, the optimum technology and economic process was obtained in the advanced purification flow scheme at a flow of 3200 m(3)/d in Harbin Wenchang WWTP. Conclusions under a lot of experiments show that: choosing the coagulation-settler plus biofilm filter for advanced purification process is reasonable; during the stable operation phase, this process showed good performance in removing the COD, BOD5, TP, NH3-N and SS; the removal rates are 50%, 39%, 67%, 50%, 80% respectively. The effluent is able to excel the requirements for wastewater reuse standards. The unit cost of the water is 0.542 yuan/m(3), which is far below the fee paid for supply water, long-distance transfer water or seawater desalination through economic analysis.     

水厂沉淀池运行参数对沉淀效果影响的数值模拟

运用已建立的二维沉淀池数学模型以及k-ε紊流模型,采用非正交同位网格下SIMPLE算法求解水动力和悬浮物沉降的耦合模型,模拟平流沉淀池中悬浮物的沉降过程,在平流沉淀池不同进水浊度和产水量Q(或停留时间T)下进行计算,得出不同运行工况下沉淀池进水浊度与出水浊度之间的定量关系,分析水厂运行管理控制对沉淀池出水质量产生的影响,为水厂提高产水效率和控制沉淀池出水水质提供参考依据。     

Particle size distribution and property of bacteria attached to carbon fines in drinking water treatment

The quantitative change and size distribution of particles in the effluents from a sand filter and a granular activated carbon （GAC） filter in a drinking water treatment plant were investigated. The average total concentration of particles in the sand filter effluent during a filter cycle was 148 particles/mL, 27 of which were larger than 2 μm in size. The concentration in the GAC effluent （561 particles/mL） was significantly greater than that in the sand filter effluent. The concentration of particles larger than 2 μm in the GAC filter effluent reached 201 particles/mL, with the amount of particles with sizes between 2 μm and 15 μm increasing. The most probable number （MPN） of carbon fines reached 43 unit/L after six hours and fines between 0.45 μm and 8.0 μm accounted for more than 50%. The total concentration of outflowing bacteria in the GAC filter effluent, 350 CFU （colony-forming units） /mL, was greater than that in the sand filter effluent, 210 CFU/mL. The desorbed bacteria concentration reached an average of 310 CFU/mg fines. The disinfection efficiency of desorbed bacteria was lower than 40% with 1.5 mg/L of chlorine. The disinfection effect showed that the inactivation rate with 2.0 mg/L of chloramine （90%） was higher than that with chlorine （70%）. Experimental results indicated that the high particle concentration in raw water and sedimentation effluent led to high levels of outflowing particles in the sand filter effluent. The activated carbon fines in the effluent accounted for a small proportion of the total particle amount, but the existing bacteria attached to carbon fines may influence the drinking water safety. The disinfection efficiency of desorbed bacteria was lower than that of free bacteria with chlorine, and the disinfection effect on bacteria attached to carbon fines with chloramine was better than that with only chlorine.     

Possibility of sewage and combined sewer overflow reuse with biological aerated filters.

The secondary effluent from municipal plants in Korea generally represents higher BOD with lower SS. Therefore, more soluble forms of organics and NH4-N need to be removed to improve its effluent for reuse. In this study reuse possibility of secondary effluent and CSO (combined sewer overflow) using BAF (biological aerated filter) was evaluated. The tertiary application with 1.2 h EBCT, SS, BOD and COD showed stable concentrations less than 1.3, 1.3 and 6.2 mg/L, respectively. Nitrogen could be nitrified even at 7 degrees suggesting BAF can be used for a water reuse method as well as an effective add-on facility in cold regions. However, BAF was not stable with CSO application at increased flow rates suggesting CSO must be equalised prior to application. Disinfection was necessary even during normal weather conditions.     

石灰软化法处理地下水源水硬度试验研究

采用石灰软化法处理某地下水源水硬度,结果表明,当石灰投加量为220mg/L,pH为8.7～8.9时,可使原水硬度和碱度分别由300mg/L和250mg/L降至115mg/L和80mg/L以下,去除率分别为61.7%和68%,沉淀和过滤对硬度去除效果影响不大;投加石灰后出水浊度明显升高,投加PAC(聚氯化铝)40mg/L,并与常规工艺联用,可使出水浊度稳定降低至0.15～0.65NTU;试验证明"石灰+PAC+常规工艺"能有效去除水中硬度和浊度,出水煮沸后不再生成沉淀和悬浮物,符合现行《生活饮用水卫生标准》(GB 5749—2006)和用户使用要求,石灰软化法药耗成本估算为0.246元/m3。