investigating the feasibility of water disinfection efficiency improvement in non-contact uv radiation
نویسندگان
چکیده
background: despite their simplicity and the low-cost, the conventional non-contact uv systems have low efficiency in water disinfection. the purpose of this study was to examine the possibility of upgrading these systems by some modifications in order to maximize the water contact with the uv radiation and as a result a better disinfection. methods: in this study, two enhanced models of non-contact uv systems were compared to the conventional model. the waterfall model was made with a design based on flowing water from two thin waterfalls around a uv lamp in order to have direct radiation from the lamp’s all exposure areas. also, the stair type model was designed in which a lamp was fixed over the shiny steel steps. the results of water disinfection in two flow rates of 0.2 and 0.4 l/s were compared with traditional design at the exact similar conditions. the disinfection efficiency of this study was measured by reduction of fecal choliforms in water which were evaluated in turbidities of 0.5, 10 and 20 ntu. findings: the disinfection efficiency of the waterfall model in the turbidity of 0.5 ntu was specified to be 3.65 log in reduction of fecal choliforms compared to the conventional model by 2.93 log reduction (p<0.05). besides, this new model was quite capable of disinfecting the water with high turbidities up to 20 ntu. however, the stair type model had less efficiency than the conventional model. conclusion: the reduction in disinfection efficiency at higher flow rates and turbidities for the waterfall model was much less than conventional model. so, application of the waterfall model in larger scales and for small water treatment facilities is suggested.
منابع مشابه
improving efficiency of disinfection of water for non-contact uv system
background: the goal was to upgrade and/or uprate the traditional non-contact array by producing few modifications in the configuration of this model in order to maximize light receiving of water from the uv lamp and a better disinfection. methods: an innovative non-contact model was made with a design based on irradiation of water, which was flowing as two thin waterfalls around a uv lamp in ...
متن کاملinvestigating the feasibility of a proposed model for geometric design of deployable arch structures
deployable scissor type structures are composed of the so-called scissor-like elements (sles), which are connected to each other at an intermediate point through a pivotal connection and allow them to be folded into a compact bundle for storage or transport. several sles are connected to each other in order to form units with regular polygonal plan views. the sides and radii of the polygons are...
Modelling the Kinetic of UV Water Disinfection
Ultraviolet disinfection is an attractive tool for treating water and eliminating pathogens with safe and available technology especially in developing countries where waterborne diseases cause the death of thousands of people every year. Even though UV is an easy tool to perform disinfection, concerns over the potential of microorganism reactivation constitute an issue for its development. In ...
متن کاملthe survey of the virtual higher education in iran and the ways of its development and improvement
این پژوهش با هدف "بررسی وضعیت موجود آموزش عالی مجازی در ایران و راههای توسعه و ارتقای آن " و با روش توصیفی-تحلیلی و پیمایشی صورت پذیرفته است. بررسی اسنادو مدارک موجود در زمینه آموزش مجازی نشان داد تعداد دانشجویان و مقاطع تحصیلی و رشته محل های دوره های الکترونیکی چندان مطلوب نبوده و از نظر کیفی نیز وضعیت شاخص خدمات آموزشی اساتید و وضعیت شبکه اینترنت در محیط آموزش مجازی نامطلوب است.
investigating the translation expectancy norms of iranian college student readership in terms of english fiction in persian
مفهوم هنجار برای اولین بار توسط دانشمندی به نام گیدون توری در اواخر دهه 70 مطرح شد. هنجارها توسط محققان مختلفی طبقه بندی شده اند؛ نوع هنجاری که در این تحقیق مورد بحث است "هنجار انتظارات" است. مطالعات ترجمه یک رشته ی نوپا و مستقل است که هنوز به رشد کامل خود نرسیده و بسیاری از شاخه های آن نیاز به پژوهش دارند. یکی ازاین حوزه ها که نیاز به پژوهش دارند، هنجارهای ترجمه هستند به ویژه هنجارهای انتظارات...
منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
تحقیقات نظام سلامتجلد ۲۰۱۱، شماره ۳، صفحات ۰-۰
میزبانی شده توسط پلتفرم ابری doprax.com
copyright © 2015-2023