scholarly journals SONOMICROBIOLOGY OF RAW WATER AT THE TREATEMENT BY AIR-JET GENERATORS

2017 ◽  
Vol 18 (2) ◽  
Author(s):  
CARMEN CIRNU ◽  
ANCA STEFAN ◽  
GEORGE BALAN
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Treatment Effect ◽  
Raw Water ◽  
Treatment Technology ◽  
Air Jet ◽  
Sonic Treatment ◽  
Ultrasound Generator ◽  
Water Plants ◽  
Microbiological Indicators

<p>The paper presents the sonic treatment effect on the microbiological indicators of the raw water, namely total germ number, Streptococci number, total coli forms and fecal coli forms. Also, the paper comprises the sonic installation which includes the vertical reactor and the air-jet ultrasound generator. The results allow the development of a new raw water treatment technology that will eliminate the actually two-stage treatment - filtration and chlorination, for the drinking water plants. </p>

scholarly journals Cyanobacteria and microcystin contamination in untreated and treated drinking water in Ghana

2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Gloria Naa Dzama Addico ◽  
Jörg D. Hardege ◽  
Jiri Kohoutek ◽  
Kweku Amoaku Atta DeGraft-Johnson ◽  
Pavel Babica
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Human Health ◽  
Metropolitan Area ◽  
Cyanobacterial Blooms ◽  
Maximal Concentration ◽  
Raw Water ◽  
Treated Water ◽  
Treated Drinking Water ◽  
Who Guideline

<p>Although cyanobacterial blooms and cyanotoxins represent a worldwide-occurring phenomenon, there are large differences among different countries in cyanotoxin-related human health risk assessment, management practices and policies. While national standards, guideline values and detailed regulatory frameworks for effective management of cyanotoxin risks have been implemented in many industrialized countries, the extent of cyanobacteria occurrence and cyanotoxin contamination in certain geographical regions is under-reported and not very well understood. Such regions include major parts of tropical West and Central Africa, a region constisting of more than 25 countries occupying an area of 12 million km<sup>2</sup>, with a total population of 500 milion people. Only few studies focusing on cyanotoxin occurrence in this region have been published so far, and reports dealing specifically with cyanotoxin contamination in drinking water are extremely scarce. In this study, we report seasonal data on cyanobacteria and microcystin (MC) contamination in drinking water reservoirs and adjacent treatment plants located in Ghana, West Africa. During January-June 2005, concentrations of MCs were monitored in four treatment plants supplying drinking water to major metropolitan areas in Ghana: the treatment plants Barekese and Owabi, which serve Kumasi Metropolitan Area, and the plants Kpong and Weija, providing water for Accra-Tema Metropolitan Area. HPLC analyses showed that 65% samples of raw water at the intake of the treatment plants contained intracellular MCs (maximal detected concentration was 8.73 µg L<sup>-1</sup>), whereas dissolved toxins were detected in 33% of the samples. Significant reduction of cyanobacterial cell counts and MC concentrations was achieved during the entire monitoring period by the applied conventional water treatment methods (alum flocculation, sedimentation, rapid sand filtration and chlorination), and MC concentration in the final treated water never exceeded 1 µg L<sup>-1</sup> (WHO guideline limit for MCs in drinking water). However, cyanobacterial cells (93-3,055 cell mL<sup>-1</sup>) were frequently found in the final treated water and intracellular MCs were detected in 17% of the samples (maximal concentration 0.61 µg L<sup>-1</sup>), while dissolved MCs were present in 14% of the final treated water samples (maximal concentration 0.81 µg L<sup>-1</sup>). It indicates a borderline efficiency of the water treatment, thus MC concentrations in drinking water might exceed the WHO guideline limit if the treatment efficiency gets compromised. In addition, MC concentrations found in the raw water intake might represent significant human health risks for people living in areas with only a limited access to the treated or underground drinking water.</p>

scholarly journals OPTIMIZATION OF THE DRINKING WATER TREATMENT PROCESS OF A SUGAR PLANT STATION IN COTE DIVOIRE

2021 ◽  
Vol 9 (01) ◽  
pp. 512-524
Author(s):  
Konan Lopez Kouame ◽  
◽  
Nogbou Emmanuel Assidjo ◽  
Andre Kone Ariban ◽  
◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Treatment Process ◽  
Polynomial Regression ◽  
Drinking Water Treatment ◽  
Optimal Dose ◽  
Raw Water ◽  
Water Treatment Process ◽  
Jar Test ◽  
Coagulation And Flocculation

This article presents an optimization of the drinking water treatment process at the SUCRIVOIRE treatment station. The objective is to optimize the coagulation and flocculation process (fundamental process of the treatment of said plant)by determining the optimal dosages of the products injected and then proposes a program for calculating the optimal dose of coagulant in order to automatically determine the optimal dose of the latter according to the raw water quality. This contribution has the advantage of saving the user from any calculations the latter simply enters the characteristics of the raw effluent using the physical interface of the program in order to obtain the optimum corresponding coagulant concentration. For the determination of the optimal coagulant doses, we performed Jar-Test flocculation tests in the laboratory over a period of three months. The results made it possible to set up a polynomial regression model of the optimal dose of alumina sulfate as a function of the raw water parameters. A program for calculating the optimal dose of coagulant was carried out on Visual Basic. The optimal doses of coagulant obtained vary from 25, 35, 40 and 45 mg/l depending on the characteristics of the raw effluent. The model obtained is: . Finally, verification tests were carried out using this model on the process. The results obtained meet the WHO drinkability standards for all parameters for a settling time of two hours.

scholarly journals Simulation of NOM events in pilot plant evaluation of DAF/Ozone/BAC for drinking water treatment

2017 ◽  
Vol 17 (6) ◽  
pp. 1793-1800
Author(s):  
Y. Yan ◽  
M. Carter ◽  
A. Mercer
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Pilot Plant ◽  
Drinking Water Treatment ◽  
Natural Occurrence ◽  
Raw Water ◽  
Humic Materials ◽  
Pilot Investigation ◽  
Brewing Method ◽  
Plant Evaluation

Abstract Pilot plant testing is invaluable for ascertaining the robustness of water treatment processes against raw water quality events such as turbidity and colour spikes, whether it be for stress testing of an existing process or designing of a new process. Unfortunately, the natural occurrence of such events (particularly colour) can be difficult to predict and commercial humic materials generally fail to closely match the indigenous natural organic matter (NOM) present in the raw water. Therefore, it is highly desirable to be able to simulate NOM event conditions. This paper describes a simple brewing method that we developed and used in our recent pilot plant evaluation of a proposed DAF/Ozone/BAC process for drinking water treatment. Using this method we successfully prepared, by using fallen leaves etc. collected from the local catchment area, large quantities of a concentrated NOM stock solution with its specific ultraviolet absorbance (SUVA), when diluted, very close to the median SUVA of historical NOM events. The brewed solution showed broadly similar NOM characteristics to those of the raw water encountered during the pilot investigation period in terms of molecular weight distribution and fractionation. The coagulation behaviour was also examined for the spiked and non-spiked raw water.

scholarly journals Predicting the residual aluminum level in water treatment process

2012 ◽  
Vol 5 (1) ◽  
pp. 243-264
Author(s):  
J. Tomperi ◽  
M. Pelo ◽  
K. Leiviskä
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Prediction Models ◽  
Treatment Plant ◽  
Warning System ◽  
High Dose ◽  
Raw Water ◽  
Residual Aluminum ◽  
Study Results ◽  
Ann Models

Abstract. In water treatment processes, aluminum salts are widely used as coagulation chemical. High dose of aluminum has been proved to be at least a minor health risk and some evidence points out that aluminum could increase the risk of Alzheimer's disease thus it is important to minimize the amount of residual aluminum in drinking water and water used at food industry. In this study, the data of a water treatment plant (WTP) was analyzed and the residual aluminum in drinking water was predicted using Multiple Linear Regression (MLR) and Artificial Neural Network (ANN) models. The purpose was to find out which variables affect the amount of residual aluminum and create simple and reliable prediction models which can be used in an early warning system (EWS). Accuracy of ANN and MLR models were compared. The new nonlinear scaling method based on generalized norms and skewness was used to scale all measurement variables to range [−2...+2] before data-analysis and modeling. The effect of data pre-processing was studied by comparing prediction results to ones achieved in an earlier study. Results showed that it is possible to predict the baseline level of residual aluminum in drinking water with a simple model. Variables that affected the most the amount of residual aluminum were among others: raw water temperature, raw water KMnO4 and PAC / KMnO4-ratio. The accuracies of MLR and ANN models were found to be almost equal. Study also showed that data pre-processing affects to the final prediction result.

scholarly journals UJI COBA PROSES KOAGULASI-FLOKULASI AIR BAKU UNTUK PDAM DANAU TELOKO DAN TELUK GELAM DI KAYU AGUNG KABUPATEN OKI PROPINSI SUMATERA SELATAN

2018 ◽  
Vol 6 (2) ◽  
Author(s):  
Petrus Nugro Rahardjo
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Quality Standards ◽  
Synthetic Polymer ◽  
Raw Water ◽  
Aluminum Sulphate ◽  
Optimum Ph ◽  
Trial Test

Regional Drinking Water Company (PDAM) of County Ogan Komering Ilir has two problematic water treatment units. The first is located in Danau Teloko and the other is in the Teluk Gelam. The main problem is that many organic pollutants (namely peat water) contained in raw water. Therefore, PDAM can not be optimal to supply all the needs of drinking water for the community. PDAM have tried to treat the raw water of peat with the process of flocculation and coagulation, but the results did not meet quality standards as drinking water. This research is a trial test to obtain the optimum condition for flocculation and coagulation processes in water treatment. The results were very succesful and get the optimum pH is about 7.5 and a chemical dose of 80 ppm Aluminum Sulphate as the coagulant. Turbidity of water produced is 4 NTU and visually looks very clean. Better to add a synthetic polymer (PAC) as an additive to the process of flocculation and coagulation. Based on calculations, PDAM Danau Teloko will require the amount of coagulant (Aluminum Sulphate) 138.24 kg per day to produce 40 liters of drinking water per second. Keywords : Raw Water, Flocculation, Coagulation,  Water Treatment Plant

scholarly journals PENINGKATAN KUALITAS AIR BAKU DENGAN PROSES BIOFILTER TERCELUP MENGGUNAKAN MEDIA STRUKTUR SARANG TAWON

2018 ◽  
Vol 7 (1) ◽  
Author(s):  
Nusa Idaman Said ◽  
Arie Herlambang
Keyword(s):  
Drinking Water ◽  
Organic Matter ◽  
Water Treatment ◽  
River Water ◽  
Residence Time ◽  
Drinking Water Treatment ◽  
Organic Substances ◽  
Raw Water ◽  
Treatment Unit ◽  
High Organic Matter

Contamination of rivers has reached an alarming level, especially in the rivers passing through major cities, agricultural areas and industrial areas. Among the contaminants that often appear dominant and very disturbing is the organic substance. The existence of high organic matter within the river water is often expressed in permanganate number that has passed the quality standard. River that contain high organic matter usually the water smell and the color is black, besides it can also cause disturbances in the water treatment process, which is an increasing use of coagulants, chlorine, activated carbon, and the emergence of substances that are not desired, and the quality of treatment results are unsatisfactory. Many ways to reduce the organic matter in river water, one of them is by using the biofilter honeycomb structure. The target of the reduction of organic substances is that the river water could be used as a raw drinking water quality standards or meet the category B, Regulation of Jakarta Governor Number 582, 1995. Raw water used for this study were taken from Krukut River which is the raw water for Regional Water Company PALYJA, Production Installation III Cilandak, South Jakarta and Cengkareng Drain river water, which is currently used as a source of raw water for PAM Taman Kota, West Jakarta using a biofilter reactor aerobic system, the capacity of 50 - 200 m3, Capasity of Blowers 300 l /min, Residence Time 6 hours up to 1 hour. Test results on the residence time of 1 hour, parameters pH, TSS, turbidity, organic substances, detergents, manganese, ammonia, nitrite, nitrate, can meet the standard, except for iron which still exceeds the standard. To improve the removal  efficiency of organic matter and iron, at the beginning of processing before entering into the drinking water treatment unit need to be added powder active carbon and an oxidizing agent with a sufficient dose. Keywords: Organic substances, biofilter, aerobic, honeycomb plastic media.

scholarly journals Fabrication of a colorimetric paper-based microfluidic sensor for residual poly-dadmac detection in water treatment

2019 ◽  
Author(s):  
◽  
Sibongile Elizabeth Magubane
Keyword(s):  
Gold Nanoparticles ◽  
Drinking Water ◽  
Surface Plasmon Resonance ◽  
Water Treatment ◽  
Surface Plasmon ◽  
Potable Water ◽  
Treatment Process ◽  
Colour Change ◽  
Raw Water ◽  
Cielab System

Poly– diallyldimethylammonium chloride (poly-DADMAC) is an established coagulant in the treatment of drinking water. Reports have indicated that poly-DADMAC can degrade into a suspected carcinogenic form which is N-nitrosodimethylamine (NDMA). Consequently, water treatment plant operators are required to know the residual concentration of polyelectrolytes at various stages in the treatment process and the eventual quality of the treated water. Historical research has proven that, over the years, a number of methods such as extraction-spectrophotometry, fluorometry and tannic acid have been developed and implemented for the analysis of polymers in drinking water. However, they produced poor linearity, sensitivity and precision, high detection limits or produced false positives due to matrix effects. The laboratory method that has proven to be simple, affordable and accurate is the colloidal titration method. However, this method cannot be used at the plant for quick and accurate monitoring of poly-DADMAC. In this study, the aim was to fabricate a Lovibond portable colorimetric comparator device based on gold nanoparticles for colorimetric quantification and detection of poly-DADMAC in raw and treated potable water. The colorimetric disk and comparator was fabricated from 14 nm gold nanoparticles with the concentration of poly-DADMAC varying from 1 to 10 mg L-1. The addition of higher concentrations of poly-DADMAC resulted in the aggregation of gold nanoparticles with the colour changing from red to blue. The gold nanoparticles were prepared via the citrate reduction method. Characterisation of the gold nanoparticles was done by ultraviolet- visible (UV/VIS) spectrophotometry and transmission electron microscopy (TEM). The Lovibond comparator was fabricated with a colour filter disk for the screening of residual poly-DADMAC in raw and potable water. The colorimetric disk was printed on the plastic slide and inserted in the plastic compartment of the comparator. The Lovibond comparator was verified with raw and potable water samples from different sampling points in and around the Mhlathuze river area located in the province of KwaZulu-Natal, South Africa. Preliminary results showed that the developed colorimetric comparator device can visually detect poly-DADMAC concentrations lower than 1 mg L-1. The colour development was first developed on normal paper and then optimised by UV/VIS spectrophotometry. The method developed has a linear range from zero to 10 mg L-1 with the correlation coefficient of R=0.9954. The effectiveness of the device was investigated by doing a recovery study on a potable water sample. Potable water is water that is suitable for drinking. In this research, potable water refers to tap water. The potable water sample was spiked with 1 mg L-1 poly-DADMAC. This exercise was done three times. The acceptance criterion for recovery is 80 to 120%. The 3 recoveries that were obtained are 107.95, 91.26 and 100.3%. The average recovery was 99.84%. This shows that the proposed method can detect poly-DADMAC with the acceptable level of accuracy. One of the important parameters that a quality method must have is selectivity. This parameter shows that the method can accurately detect the analyte of interest in the midst of different matrices. This was done by analysing the raw water samples together with their treated samples. Physical-chemical parameters were also analysed to show the broader state of the samples. The poly-DADMAC results obtained from the UV/VIS spectrophotometer compared quite well with those obtained from using the Lovibond colorimetric filter. The limited observation of colours using our eyes is a major contributor of systematic errors during the application of colorimetric devices. Thus, such a limitation can be reduced by using CIELAB system. A gold nanoparticle-based colorimetric CIELAB system for detection of poly-DADMAC in potable and raw water was also demonstrated. The method is based on the application of a paper-based analytical device which is printed on the normal A4 white printing paper. Fully enclosed 6 X 9 hydrophobic wells were fabricated on this paper. This work provides a clear evidence of the application of CIELAB colour system, and thus, replacing the conventional spectrophotometric technique to quantify polymers. Results of this work showed that the intensity of the fabricated well is proportional to the concentration of the detected polymer. The change in colour (ΔE) was calculated for each fabricated well and clear evidence of the colour change was observed upon the variation of the polymer. Moreover to the application of ΔE, the chromaticity using CIEYxy was used to verify colour change, it was observed that they followed the expected shift from red to blue, symbolising aggregation due to Van Der Waal inter-particle attractions as a result of the addition of poly-DADMAC. The results of this experiment were validated using the spectrophotometric technique which further emphasised the appearance of the new surface Plasmon resonance peak formed at 610nm symbolising aggregation. Importantly, the intensity of the new Surface Plasmon Resonance (SPR) peak at 610 nm increased by increasing the concentration of poly-DADMAC. Comparison of the Lovibond and UV/VIS results showed that there was no significant difference between the two methods. This proved that the fabricated Lovibond colour comparator is capable of the detection of residual poly-DADMAC in water treatment. This therefore implies that plant operators can be able to detect poly-DADMAC at any stage during the water treatment process by using a rapid, user-friendly portable device.

scholarly journals Characterization of microbial regrowth potential shaped by advanced drinking water treatment

2021 ◽  
Author(s):  
Ikuro Kasuga ◽  
Hitomi Nakamura ◽  
Futoshi Kurisu ◽  
Hiroaki Furumai
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Organic Carbon ◽  
Microbial Communities ◽  
Drinking Water Treatment ◽  
Raw Water ◽  
Assimilable Organic Carbon ◽  
Water Transportation ◽  
Microbial Regrowth ◽  
Treatment Step

Abstract Microbial regrowth in premise plumbing is a threat to water safety. Disinfectant residuals are often diminished during water transportation and stagnation, leading to the regrowth of opportunistic pathogens. Although microbial regrowth potential is mostly determined by water treatment, little is known about how each treatment step affects two key factors that contribute to microbial regrowth potential: biodegradable organic matter and microbial abundance. In this study, we operated annular reactors to evaluate the microbial regrowth potential of water shaped after each treatment step in a full-scale drinking water treatment plant with ozonation and biological activated carbon filtration. The assimilable organic carbon and total cell count (TCC) were stable at all treatment steps during the sampling period from July to October 2015. The assimilable organic carbon consumption and TCC net increase in the annular reactors indicated that apparent growth yields (cell number base) of microbial communities were different in each reactor. Regrowth potential evaluated by indigenous microbial community in finished water was reduced to 22% of that in raw water, while 75% of assimilable organic carbon in raw water remained in finished water. It suggested that treatment performance evaluated by indigenous microbial communities was better than that evaluated by assimilable organic carbon.

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