The bactericidal effect of lime flocculation/flotation as a primary unit process in a multiple system for the advanced purification of sewage works effluent

An important advantage of using lime as flocculant in water purification processes is that bacteria are not only removed by coagulation but also destroyed by the hydroxide alkalinity. This communication deals with the bactericidal effect of lime in a flocculation/ flotation unit which is the primary and key process in a multiple system experimental plant for the reclamation of potable water from secondary treated sewage effluent. Laboratory and field tests revealed a marked difference in the survival of Gram-negative, Gram-positive and acidfast bacteria. Previous studies on the bactericidal effect of lime in water treatment processes included only Gram-negative organisms. These bacteria were considerably more sensitive than the other two groups and possible reasons for the differentiation in resistance are discussed. Raising the pH value of humus tank effluent to 11·5 for a period of 1 hr destroyed all Gram-negative bacteria and reduced the plate count by more than 99 per cent. Surviving organisms consisted mainly of spore-formers. This treatment had almost no effect on mycobacteria.     

机械蒸汽再压缩技术处理反渗透浓水的中试研究

近年来,反渗透(RO)在污水厂二级出水深度处理中的应用越来越多.然而,RO浓水的含盐量较高、有机物难于降解,采用常规方法处理时出水水质难于达到排放标准.采用机械蒸汽再压缩技术(MVR)对某污水厂的反渗透浓水进行了6倍浓缩的中试,其出水COD≤50 mg/L、NH<,3>-N≤10 mg/L,可以达到<城市污水再生利用城市杂用水水质>(GB/T 18920-2002)的要求;COD、TDS、Mg<'2+>和色度等指标的浓缩倍数与体系的浓缩倍数基本一致,而浓缩水中的TP、SiO<,2>、TN、NH<,3>-N浓度却低于原水的,这主要是由于磷酸盐、硅酸盐的沉淀和氨气逸出所致.另外,钙盐等的沉淀作用还造成浓缩水中SS浓度的增加.由此可见,利用MVR处理反渗透浓水在技术上是可行的,但是需要增加沉淀物的预处理和排出气体的收集处理装置.     

斜管沉淀池-活性砂过滤工艺在城镇污水处理厂中的应用

针对株洲南部区域污水进水水质浓度较低、容易出现短时高浓度的情况,采用斜管沉淀池-活性砂滤池对二沉池出水进行深度处理,以保证其出水水质达到GB 189182002《城镇污水处理厂污染物排放标准》一级A标准。经过深度处理后,COD、SS、BOD5、NH3-N、TP去除率均优于一级A标准,出水可作为再生水使用。对此工艺进行技术经济分析,结果表明该工艺具有占地面积小、高效节能等优点,可为同类污水处理技术提供参考。     

MIBR/纳滤组合工艺用于再生水回用工程

以生活污水为对象,采用膜固定化微生物反应器（MIBR）／纳滤组合工艺进行再生水回用处理,出水水质达到《生活饮用水卫生标准》（GB5749-2006）中“农村小型集中式供水和分散式供水部分水质指标及限制”标准。该组合工艺流程简单、投资省、出水水质好、自动化程度高,为严重缺水地区（尤其是铁路沿线站点）解决洗衣、洗浴等用水提供了新思路。     

Pharmaceuticals and personal care products (PPCPs) in surface and treated waters of Louisiana,USA and Ontario,Canada

A newly developed analytical method was used to measure concentrations of nine pharmaceuticals and personal care products (PPCPs) in samples from two surface water bodies, a sewage treatment plant effluent and various stages of a drinking water treatment plant in Louisiana, USA, and from one surface water body, a drinking water treatment plant and a pilot plant in Ontario, Canada. The analytical method provides for simultaneous extraction and quantification of the following broad range of PPCPs and endocrine-disrupting chemicals: naproxen; ibuprofen; estrone; 17beta-estradiol; bisphenol A; clorophene; triclosan; fluoxetine; and clofibric acid. Naproxen was detected in Louisiana sewage treatment plant effluent at 81-106 ng/l and Louisiana and Ontario surface waters at 22-107 ng/l. Triclosan was detected in Louisiana sewage treatment plant effluent at 10-21 ng/l. Of the three surface waters sampled, clofibric acid was detected in Detroit River water at 103 ng/l, but not in Mississippi River or Lake Pontchartrain waters. None of the other target analytes were detected above their method detection limits. Based on results at various stages of treatment, conventional drinking-water treatment processes (coagulation, flocculation and sedimentation) plus continuous addition of powdered activated carbon at a dosage of 2 mg/l did not remove naproxen from Mississippi River waters. However, chlorination, ozonation and dual media filtration processes reduced the concentration of naproxen below detection in Mississippi River and Detroit River waters and reduced clofibric acid in Detroit River waters. Results of this study demonstrate that existing water treatment technologies can effectively remove certain PPCPs. In addition, our study demonstrates the importance of obtaining data on removal mechanisms and byproducts associated with PPCPs and other endocrine-disrupting chemicals in drinking water and sewage treatment processes.     

石灰法出水对冷却系统腐蚀、结垢的影响

石灰法是城市污水再生回用于工业循环冷却系统的重要技术.为考察石灰法处理出水对冷却系统的影响,将北京某城市污水厂二沉池出水经石灰法处理后回用于电厂循环冷却系统,试验结果表明,与二沉池出水相比,石灰法出水具有更强的腐蚀性,并且易生成碳酸钙和磷酸钙,但不易生成硫酸钙和硅酸镁;通过采取缓蚀阻垢措施可以很好地防止循环冷却水腐蚀和结垢状况对机组运行的影响.     

污泥浓缩脱水一体化技术应用探讨

传统的污泥浓缩脱水工艺存在着占地大、投资多、管理复杂、污泥容易流失、除磷效果差的缺陷,严重地影响看污水处理厂建设的良性发展。提出了污泥浓缩脱水一体化技术在污水处理厂中的应用,并就其基本原理和技术特点进行了阐述。为污水处理厂污染工艺选择提供了一种新的思路。对加快污水处理厂建设,提高出水标准,保护环境起到积极的作用。     

Comparison of engineering costs of raw freshwater, reclaimed water and seawater for toilet flushing in Hong Kong

Hong Kong is one of the very few coastal cities in the world that use ‘dual water supply systems’. Dual water supply involves two distribution systems: a freshwater system for potable use and a seawater system for toilet flushing. This study looks into the feasibility, from an engineering cost point of view, of extending seawater supply into districts where potable water is still being used for toilet flushing, including South District of Hong Kong Island, Sai Kung, Northern New Territories and Northwest New Territories. Besides seawater, raw (untreated) freshwater and reclaimed water (treated effluent from local sewage treatment works) are also considered to be used for toilet flushing for these districts. Six cases are developed for comparison by using the lowest net present value of cost criterion. The result shows that using seawater for toilet flushing in these districts has the best engineering economy.     

UBAF＋砂滤工艺废水深度净化的应用研究

进行了以上向流曝气生物滤池 砂滤池处理工艺模拟城市污水处理厂的二级生化出水的试验,得出了出水水质优于城市杂用水和景观用水及部分工业冷却用水的结论,以推动UBAF 砂滤工艺废水深度深化的研究。     

废塑料造粒洗气废水处理工程实例

废塑料造粒生产过程中的废气采用水吸收作为预处理,会产生高浓度难降解有机废水。先通过气浮去除水中浮油、悬浮物,再经过Fenton氧化预处理,提高其可生化性,然后采用UASB+接触氧化工艺处理,最后用次氯酸钠去除部分氨氮,其出水水质达到所在工业园区污水厂纳管标准(COD≤350 mg/L、NH₃-N≤50 mg/L、甲苯≤0.2 mg/L)。工程调试运行结果显示,COD、NH₃-N和甲苯平均去除率分别达96.1%、89.9%、99.8%,在技术上和经济上是可行的。     

太原循环经济环卫产业园固体废物污水处理厂工艺设计

为解决太原循环经济环卫产业园内生活垃圾焚烧处理处置、餐厨垃圾处理处置及其他固废处理处置过程中产生的高浓度废水处理问题,拟新建一座污水处理厂。设计处理规模为1 200 t/d,主要包括750 t/d的焚烧厂垃圾渗滤液和450 t/d的餐厨沼液。渗滤液处理采用"气浮+调节池+内循环厌氧反应器+两级A/O-MBR"的核心工艺,餐厨沼液处理采用"气浮+调节池+两级A/O-MBR"的核心工艺。污泥处理采用"离心脱水+热干化"工艺,处理后污泥含水率≤30%,干化污泥采用密封车辆送至焚烧厂焚烧处理。试运行结果表明,出水水质稳定达到设计标准。污水处理厂总投资为1.3亿元,污水处理直接成本为23.5元/t。     

河南省博爱县污水处理厂设计介绍

根据博爱县污水处理厂进出水水质,选择奥贝尔氧化沟作为该工程的主体工艺,并介绍了该污水处理厂主要工艺设计参数及工艺特点,以利于博爱县的城市建设,提高该县的经济效益、社会效益和环境效益。     

Fate of synthetic musks in a domestic wastewater treatment plant and in an agricultural field amended with biosolids

Synthetic musks are widely used as fragrance ingredients in personal care products, and they enter domestic wastewater treatment plants (WWTPs) through discharges into municipal sewage systems. Samples of aqueous sewage and biosolids collected from the Peterborough Wastewater Treatment Plant (WWTP), Ontario, Canada were analyzed for 11 synthetic musk compounds using GC/MS. The results showed that 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta[g]-2-benzopyrane (HHCB, 173.1+/-43.4 ng/L) and 7-acetyl-1,1,3,4,4,6-hexamethyl-tetrahydronaphthalene (AHTN, 41.6+/-15.8 ng/L) were the dominant fragrances in sewage, but other polycyclic musks and nitro musks were present at lower concentrations. The concentrations of HHCB and AHTN in the aqueous phase of the sewage were highly correlated with both BOD5 and TOC. The overall removal efficiency of synthetic musks from the aqueous sewage in the WWTP ranged from 43.3% to 56.9%, but removal occurred mainly by partitioning into the biosolids. Based on a mass balance model, the daily input and output of HHCB and AHTN in the Peterborough WWTP were 47 g and 46 g, respectively. In an agricultural field amended with biosolids from the Peterborough WWTP, HHCB and AHTN were detected in soil immediately after application at mean concentrations of 1.0 and 1.3 mug/kg, respectively, but concentrations declined relatively rapidly over the next 6 weeks, post-application.     

双膜法在市政污水处理厂的应用

天津市某污水处理厂再生水回用工程采用双膜法工艺,近期设计规模为2.0×10^4m^3/d,本文介绍了其工艺流程、设备配置情况、工程设计参数等.运行结果表明,采用双膜法对废水进行处理后出水水质良好,可以达到回用标准,其中超滤出水浊度为0.01～0.04 NTU,反渗透产水电导率＜ 15 μs/cm,脱盐率大于99％.经济性分析结果显示,该双膜法再生水回用工程的吨水运行成本为1.584元,具有良好的经济及环境效益.     

Recovery of viruses from waste-water and effluent by the direct inoculation method

Chloroform or antibiotic treated sewage and effluent samples were inoculated directly onto MK₂ or Vero cell monolayers for enterovirus recovery. The results obtained showed a high enterovirus recovery. The average PFU (100 ml)⁻¹ from sewage samples was 4496 and from effluent samples was 5684. The conventional ratio of enteroviruses to coliforms in sewage is considered to be 1:65,000. By the direct inoculation method the ratio obtained was 1: 20,000 for sewage and 1: 2000 for effluent. It is believed the number of enteroviruses in sewage to be even higher than the ones obtained.     

Comparative study of the estrogenic responses of mirror carp (Cyprinus carpio) exposed to treated municipal sewage effluent (Lisbon) during two periods in different seasons

To assess the estrogenic potency of the treated domestic sewage effluent from a sewage treatment plant (STP) located in Lisbon (Chelas), 60 mirror carp (Cyprinus carpio) were exposed to different concentrations of the sewage effluent (0%, 25%, 50% and 100%) for two periods of 28 days in two different seasons (winter/spring). Vitellogenin induction in males was used as a biomarker of exposure to xenoestrogens. At the end of the experiment, blood samples were taken for vitellogenin analysis and the fish were sacrificed and dissected. Gonad samples were taken for histological evaluation of the sewage effects. The results showed an increase in vitellogenin induction in exposed fish, both males and females, depending on the different dilutions of the sewage effluent. In comparison with controls, the gonadosomatic index decreased significantly (P < 0.05) in fish exposed to 100% treated effluent. Although statistically not significant, the hepatosomatic index (HSI) was high in all exposed fish. Histological abnormalities in fish gonads were evaluated and related to the different percentages of sewage effluent. Seasonal variations found in estrogenic responses were attributed to weather influences on sewage dilution.     

SBR工艺处理低负荷城市污水经验探讨

以天津市某污水厂SBR工艺的调试运行为例,阐述了SBR工艺的污泥培养过程,并通过试运行期进出水水质的对比分析,得出了在进水有机负荷偏低的情况下,适用于该污水厂的SBR工艺的运行参数,即进水1h、曝气4h、静沉2h、排水1h、运行周期为8h的运行方式。在该运行条件下,出水水质能完全达到设计要求,可为利用生物法处理低负荷污水的工艺设计和运行提供参考和经验。     

城市污水工程规划设计探讨

结合株洲市排水工程专项规划的编制工作,提出了污水量预测方法,分析了城市污水处理厂布局、处理工艺及出水水质,局部应用了污水分散处理方法,规划了污泥的处理工艺及处置方法,提出了污水管网及泵站的规划原则与方法,对于类似城市的污水工程规划设计具有重要意义。     

压力曝气生物滤池处理生活污水的中试研究

为避免新兴城市小区、小城镇、度假村等分散污水的直接排放而污染环境,研制出一种小型生活污水处理设备,并以某污水厂的沉砂池出水为原水进行中试研究,考察了其处理效能.结果表明,这是一种经济实用的分散式处理⒌工艺,对生活污水中的污染物具有较好的去除效果,出水水质良好;该设备启动较快,当水温>20 ℃时自然挂膜大约需要28 d,可采用对氨氮和亚硝酸盐氮的去除效果达到稳定作为设备启动成功的判定标准;该工艺较适宜的进水COD负荷为5-30kg/(m3·d),进水SS浓度宜控制在80 mg/L以下,适宜的运行温度为15～30 oC,当温度<10℃时可通过延长水力停留时间来提高处理效果.