scholarly journals Use of the direct and cultivation methods in the bacteriological examination of water in water supply system

2011 ◽  
Vol 27 (3) ◽  
pp. 1337-1343 ◽  
Author(s):  
S. Ciric ◽  
Z. Ilic ◽  
B. Milosevic ◽  
Z. Spasic ◽  
J. Stojkovic

Bacterial abundance in the water used for drinking by humans and animals is a parameter that is closely linked to their health. Therefore, application of a method of detection of bacterial count which will indicate the real status of this parameter, as authentically as possible, is necessary. The bacterial load of water in certain stages of water supply using direct and cultivation methods was investigated. In the cultivation method, the water samples were inoculated on PCA and on R2A medium, and incubated for 7 days at 37 ?C and at room temperature. Direct method included filtration of samples stained with acridine orange and counting of bacteria on the filters under the epifluorescence microscope. Cultivation and direct methods showed the lowest bacterial count in the tank of Bagdala II, 0 cfu/ml and 611 bacteria/ml, respectively, and maximum abundance in raw water, 157 cfu/ml and 1,378,698 bacteria/ml, respectively. Statistical analysis showed that significantly higher count of bacteria was recorded on R2A medium compared to PCA, and at room temperature than at 37 ?C. By index TBC/AMB, the native raw water was classified as more polluted water when applying the results obtained at room temperature compared to the results obtained at 37 ?C. The most realistic bacteriological status of all water types was obtained using the direct method of quantification of bacteria. However, for routine monitoring of water in water supply system, as well as for the examination of bacterial regrowth in the distribution network, it is the best to apply the cultivation method which involves inoculation of samples on R2A medium and incubation at room temperature.

Water ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1426 ◽  
Author(s):  
Zhiqiang Jiang ◽  
Chao Wang ◽  
Yi Liu ◽  
Zhongkai Feng ◽  
Changming Ji ◽  
...  

In order to allocate the raw water of the complex water supply system in Shenzhen reasonably, this paper studied the complex network relationship of this large-scale urban water supply system, which consists of 46 reservoirs, 67 waterworks, 2 external diversion water sources, 14 pumping stations and 9 gates, and described each component of the system with the concepts of point, line and plane. Using the topological analysis technology and graph theory, a generalized model of the network topological structure of the urban water allocation system was established. On this basis, combined with the water demand prediction and allocation model of waterworks, a water resources allocation model was established, aiming at satisfying the guaranteed rate of the water supply. The decomposition and coordination principle of the large-scale system and the dynamic simulation technology of the supply-demand balance were adopted to solve the model. The forward calculation mode of controlling waterworks and pumps, and the reverse calculation mode of controlling reservoirs and waterworks were designed in solving the model, and a double-layer feedback mechanism was formed, which took the reverse calculation mode as outer feedback and the reservoir water level constraint or pipeline capacity constraint as inner feedback. Through the verification calculation of the case study, it was found that the proposed model can deal well with the raw water allocation of a large-scale complex water supply system, which had an important application value and a practical significance.


2010 ◽  
Vol 62 (1) ◽  
pp. 140-147 ◽  
Author(s):  
M. M. Islam ◽  
F. N.-F. Chou ◽  
C.-H. Liaw

The water shortage of today's world is one of the most challenging problems and the world is looking for the best solution to reduce it. Some human made causes and also natural causes are liable for the shortage of the existing water supply system. In Taiwan, especially during typhoon, the turbidity of raw water increases beyond the treatment level and the plant cannot supply required amount of water. To make the system effective, a couple of days are needed and the shortage occurs. The purpose of this study is to solve this emergency shortage problem. A dual-mode Rainwater Harvesting System (RWHS) was designed for this study as a supplement to the existing water supply system to support some selected non-potable components such as toilet and urinal flushing of an elementary school. An optimal design algorithm was developed using YAS (yield after spillage) and YBS (yield before spillage) release rules. The study result proved that an optimum volume of tank can solve the emergency water shortage properly. The system was found to be more reliable in Taipei area than that of Tainan area. The study also discovered that a government subsidy would be needed to promote the system in Taiwan.


2018 ◽  
Vol 28 (4) ◽  
pp. 1259-1264
Author(s):  
Kiril Lisichkov ◽  
Katerina Atkovska ◽  
Neven Trajchevski ◽  
Orce Popovski ◽  
Nadica Todorovska

The presence of some chemical compounds at higher levels than maximum permissible concentrations (MPC) in the drinking water, suggests of water resources pollution. In this paper the following elements were analyzed: total arsenic, cadmium, lead, cooper and zinc. Twelve samples of water from the water supply system from the city of Skopje were examined during one year from three different springs. Also, ten samples of bottled water from three producers from the Macedonian market were tested.The determined average mass concentrations of total As, Cd(II), Pb(II), Cu(II) and Zn(II) in the analyzed water samples from the water supply system are 1.35 μg/l, 0.06 μg/l, 0.6 μg/l, 0.9 μg/l and 1,12 μg/l, respectively, and for the tested bottled water, the mean values ranges from 0.56 - 0.83 μg total As / l, 0.053 - 0.056 μg Cd(II)/l, 0.51 - 0.54 μg Pb(II)/l , 0.6 - 0.87 μg Cu(II)/l and 0.68 - 0.8 μg Zn(II)/l water.The following instrumental analytical methods and techniques were used for the analysis of the tested samples of drinking water: flame atomic absorption spectroscopy (AAS), atomic absorption spectroscopy with hydride cеll, electrothermal atomic absorption spectroscopy.The obtained results are shown in tables and graphic form. According to the obtained results a comparative analysis was carried out indicate that it is a water of good quality that can be used in different branches of the process industry.The obtained results in this paper do not exceed the values of the MPC of the Republic of Macedonia prescribed by the legal regulations for the drinking water, which confirm the health safety of the drinking water from the water supply system in the city of Skopje and the packed waters from the Macedonian market in relation to the tested elements.


1993 ◽  
Vol 27 (9) ◽  
pp. 29-36 ◽  
Author(s):  
J. E. Rose

The Kafr El Sheikh Water Supply Project is a comprehensive endeavour to provide the physical and institutional resources for an effective and sustainable water supply system for 2 million persons in a developing rural Governorate in the Delta region of Egypt. The paper describes the aims of the Management Component, the institutional development of an integrated water supply and sewerage company and the main activities to-date. These include training, operational improvements, health education and finance development. Further support is required until all engineering and institutional development work has been completed.


2018 ◽  
Vol 16 (2) ◽  
pp. 84
Author(s):  
G A Blagodatsky ◽  
A A Bass ◽  
M M Gorokhov ◽  
D S Ponomarev

Работа посвящена системному анализу данных показателей исходной воды при производстве питьевой воды в системе центрального водоснабжения крупного населенного пункта. На сегодняшний день на фоне увеличивающегося негативного антропогенного воздействия на окружающую среду наблюдается ухудшение состояния многих источников питьевого водоснабжения в широком спектре показателей, в частности, таких как органолептические свойства воды. Как следствие, возникает проблема и для питьевой воды. В работе приводится процесс подготовки данных о параметрах исходной воды, забираемой из водохранилища, которые ежемесячно (с 2002 по 2014 год) учитывались на предприятии при дезодорации воды. Приведенные параметры оказывают существенное влияние на органолептические свойства конечной воды. Подготовка данных для анализа проводится методом главных компонент К. Пирсона. Данные, полученные в пространстве R9, переводятся в пространство меньшей размерности R3. Понижение размерности позволяет снизить автокорреляцию между компонентами. Отбор компонент в пространство R3 проводится по правилу Парето. В пространстве R3 методом сферической кластеризации данных «Форель» с постоянным радиусом группировки проводится кластеризация. Приводится пошаговое визуальное представление алгоритма кластеризации в пространстве R3. В работе показано, что в данных показателях качества исходной воды имеются кластеры. Проводится корреляционно-регрессионный анализ данных, представленных в главных компонентах. Строятся регрессионные зависимости показателей органолептических свойств от главных компонент из пространства R3.


Sign in / Sign up

Export Citation Format

Share Document