医院污水消毒处理技术浅析

在介绍医院污水的来源和危害及传统消毒处理方法的基础上，着重对ClO2消毒技术的特点及其在污水消毒处理上的应用进行了探讨，指出了ClO2消毒技术是一种最具竞争力的优选消毒处理工艺技术，值得推广使用。     

Chlorination and Drinking Water Quality - an Operational Overview

A vailable national guidelines for disinfection practice, and for the examination of bacteriological quality, are reviewed, together with the legislative requirements of the EC 'Drinking Water'Directive. Problems of impracticability, vagueness, and ambiguity are identified.
Experience of the maintenance of bacteriological quality in large, lowland, surface water and ground-water supply areas is given with reference to the behaviour of disinfectant residuals, trihalomethanes, nitrite, and aesthetic parameters. The way forward in terms of the management of distribution systems and water treatment is discussed.     

Disinfection of advanced wastewater treatment effluent by chlorine, chlorine dioxide and ozone: Experiments using seeded poliovirus

Chlorine, chlorine dioxide and ozone were tested as chemical disinfectants against seeded poliovirus and naturally-occurring fecal coliform organisms in wastewater effluent that had received secondary treatment followed by bench scale advanced wastewater treatment (AWT). The AWT sequence consisted of chemical treatment with lime or alum followed by mixed media filtration. The resulting effluent had low suspended solids concentrations but chemical oxygen demand and nitrogen concentrations only slightly lower than those of secondary effluent. Lime treatment produced greater reductions than alum treatment in virus numbers, but not in fecal coliform organisms.

With both chlorine and chlorine dioxide, in order to reduce seeded poliovirus to less than detectable levels, it was necessary to use doses comparable to those required to disinfect secondary effluent. The required contact times of 30–60 min were also comparable. Utilized ozone doses of 2–4 mg l⁻¹ were required to reduce seeded poliovirus to less than detectable levels in AWT effluent. Naturally-occurring fecal coliform organisms were unaffected at these ozone doses, but were inactivated at higher doses. Because they were more resistant than seeded poliovirus to ozone, fecal coliform organisms show promise as indicators for ozone disinfection.     

茶多酚用于饮用水消毒影响因素的试验研究

茶多酚除具有抗氧化、抗肿瘤、调节免疫等多种药理学作用外，还具有广谱而强效的抑菌作用。介绍了茶多酚投加入原水后，持续48h时间内的消毒效果差异；进行了同一接触时间、不同硬度原水、不同茶多酚投加量的此较试验，并找到了使水样剩余菌落数满足国家标准和行业标准的最佳多酚投加量，对简化试验过程、降低茶多酚投加量、从而降低消毒成本具有指导意义。     

The Pre-design of Berenplaat Water-Treatment Works, Rotterdam: Additional Processes to Achieve Biologically Stable Water

Biological regrowth in a water distribution system can be avoided by either maintaining a free chlorine residual to suppress growth or controlling conditions which may support growth, or by a combination of both. Micro-organisms will grow in water only if nutrients are present in sufficient amounts; conversely the reduction of biodegradable nutrients in water is vitally important in controlling the regrowth of microorganisms and zooplankton in the distribution system. The measurement of assimilable organic carbon has been developed as a way of evaluating the concentration of biodegradable material which is available to support such biological growth.
This paper describes the pilot-plant and full-scale studies carried out at the Berenplaat water-treatment works, Rotterdam to (a) improve disinfection, (b) eliminate the formation of trihalomethanes and other halogenated compounds formed by chlorination, and (c) reduce the final water assimilable organic carbon concentrations to very low levels, so that a high degree of biological stability can be maintained in the distribution system.     

Disinfection of water by electrochemical treatment

Natural water, highly contaminated with coliforms, was electrochemically treated in a stirred batch system with the use of two Ti electrodes and direct current, the polarity of which alternated automatically in half cycles of 1 min. The process was found to be effective and the percentage of the initial concentration of bacteria which were destroyed was found to be proportional to both treatment time and the square of current density obeying the kinetic model = ki² t; consequently the time needed for complete disinfection was inversely proportional to the square of current density. The percentage above was found to be independent of the initial concentration of germs at least for the range of concentrations employed. The residual disinfection capacity, after completion of the electrochemical treatment, was also verified by mixing electrochemically treated, disinfected natural water with contaminated water.     

Disinfection of Sewage Effluents: The Jersey Experience

About 35 years ago the island of Jersey in the Channel Islands set about rationalizing and modernizing its sewage-treatment operations. Treatment was carried out in one central, advanced sewagetreatment works producing a Royal Commission effluent which received nominal dilution in a small stream before discharging into the sea in one of the foremost bathing areas on the island.
In 1989, a thorough investigation was carried out on the options to secure an environmentally acceptable solution to effluent disposal. The investigation concluded that disinfection, in combination with a change to the outfall discharge point, offered the most cost-effective solution. Alternative disinfection techniques were identified, which recognized the nature and sensitivity of the receiving waters and the limited space available on the site. Only ultraviolet disinfection was suitable.
An ultraviolet disinfection system depends on the exposure of the micro-organisms causing disease to their germicidal wavelength. Light of this wavelength (about 253.7 nanometres) is absorbed by the nucleic acids in the cell which damages or rearranges the genetic information, effectively rendering the cell unable to replicate and resulting in the death of the cell.
In over 300 installations in North America the system has proven to be reliable, simple, economic and, above all, environmentally acceptable.
An ultraviolet disinfection system is currently being installed at Bellozanne, Jersey.     

Secondary Disinfection of Service Reservoirs

In order to comply with the European Community Directive on the quality of water intended for human consumption', which was embodied in the 1989 Water Act, a number of problems need to be addressed. One such problem is to identify a reliable method of secondary disinfection for service reservoirs which have a history of bacteriological failures.
This paper considers the advantages and disadvantages of ultraviolet (UV) and chemical disinfection techniques (both hypochlorite dosing and on-site generation of chlorine), together with the basic design features, and presents a case study examining capital and revenue costs. The collated information suggests that UV disinfection is a cost-effective secondary-disinfection technique. This suggestion is supported not only by the cost benefits but also by the ease of operation, improved monitoring and control, and elimination of water quality problems associated with chemical techniques.     

绍兴游泳健身中心的水处理系统设计特点

介绍了绍兴游泳健身中心水循环处理系统的设计特点:采用池底布水、池面回水的循环供水方式,使系统布水均匀;采用斜面回水沟直接回水方式解决了回水噪声问题;采用臭氧消毒辅以氯消毒方式保证了消毒安全可靠、稳定高效;通过分流加热和延长泳池初次加热时间,减小了加热设备的规格和热膨胀对系统的危害.实际运行表明,上述措施设计合理,运行效果良好.     

滤池反冲洗废水的直接回流利用研究

通过小试研究了滤池反冲洗废水直接回流利用对出水水质的影响.结果表明,反冲洗废水的直接回流利用对混凝过程有较为明显的强化作用,能够降低出水浊度和残余铝含量;当回流比例<10%时,对出水TOC没有影响;反冲洗废水的直接回流利用会导致出水细菌总数有少量增加,但不会影响消毒效果,同时对总余氯衰减的影响也很小.UFC试验的结果表明,反冲洗废水直接回流利用仅会造成消毒副产物前质含量轻微升高,其增幅为4.5%～7.6%.