Evaluation of drinking water treatment plant efficiency in microorganism removal by the coliphage, total coliform and H2S paper strip tests

1997 ◽  
Vol 35 (11-12) ◽  
pp. 403-407 ◽  
Author(s):  
M. T. Martins ◽  
G. Castillo ◽  
B. J. Dutka
Keyword(s):  
Water Quality ◽  
Water Treatment ◽  
Potable Water ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Total Coliform ◽  
Paper Strip ◽  
Total Coliforms ◽  
Strip Test ◽  
Potable Water Quality

Two potable water quality monitoring tests, the H2S paper strip test and coliphage test, were evaluated on Chilean raw potable source waters and drinking waters that had received conventional treatment to render them safe for drinking. Based on 108 samples in this study, it was found that the H2S paper strip provided consumers with equivalent to, or greater protection than, the total coliform MPN test. In treated water, a highly significant relationship (P =<0.0001) between total coliforms and H2S paper strip tests was observed. Significant relationships were also observed between total coliforms/coliphage and residual chlorine/H2S paper strip test. These studies provide evidence that the H2S paper strip test and the coliphage test are viable indicators of potable water quality and water treatment in two medium-sized cities in Chile.

scholarly journals Trihalomethane precursor reactivity changes in drinking water treatment unit processes during a storm event

2019 ◽  
Vol 19 (7) ◽  
pp. 2098-2106
Author(s):  
Chelsea W. Neil ◽  
Yingying Zhao ◽  
Amy Zhao ◽  
Jill Neal ◽  
Maria Meyer ◽  
...  
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Treatment ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Plant Performance ◽  
Storm Event ◽  
Source Water ◽  
Treatment Unit ◽  
Source Water Quality

Abstract Source water quality can significantly impact the efficacy of water treatment unit processes and the formation of chlorinated and brominated trihalomethanes (THMs). Current water treatment plant performance models may not accurately capture how source water quality variations, such as organic matter variability, can impact treatment unit processes. To investigate these impacts, a field study was conducted wherein water samples were collected along the treatment train for 72 hours during a storm event. Systematic sampling and detailed analyses of water quality parameters, including non-purgeable organic carbon (NPOC), UV absorbance, and THM concentrations, as well as chlorine spiking experiments, reveal how the THM formation potential changes in response to treatment unit processes. Results show that the NPOC remaining after treatment has an increased reactivity towards forming THMs, and that brominated THMs form more readily than chlorinated counterparts in a competitive reaction. Thus both the reactivity and quantity of THM precursors must be considered to maintain compliance with drinking water standards, a finding that should be incorporated into the development of model-assisted treatment operation and optimization. Advanced granular activated carbon (GAC) treatment beyond conventional coagulation–flocculation–sedimentation processes may also be necessary to remove the surge loading of THM-formation precursors during a storm event.

A Case Study on the Automatic Control of Chemical Dosing Processes for Full-Scale Drinking Water Treatment

2012 ◽  
Vol 209-211 ◽  
pp. 1981-1985 ◽  
Author(s):  
Dong Sheng Wang ◽  
Xing Peng Zhou ◽  
Xiao Ming Mo ◽  
Yi Wang
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Treatment ◽  
Automatic Control ◽  
Water Flow ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Constant Attention ◽  
Operational Conditions ◽  
Quality Water

During drinking water treatment, the chemical dosing processes, such as coagulant dosing process, ozone dosing process and chlorine dosing process are usually manually operated based on the operator knowledge and experience. However, due to the variations of water quality, water flow and process operational conditions and characteristics of large time-delay and nonlinear for the chemical dosing processes, it is difficult to adjust the chemical dosages in time by operators to keep the treated water quality stable, especially during the periods of rapid and frequent variations of water quality, water flow and process operational conditions. Thus, the improvements of control methods for the chemical dosing processes are essential to the operation of drinking water treatment plants. The Xiangcheng Water Treatment Plant in Suzhou, China has been utilizing the automatic control for chemical dosing processes since February 2012. Automatic controllers are designed respectively for the coagulant dosing process, ozone dosing process and chlorine dosing process. After the implementation of automatic control, operators are not necessary to keep constant attention. In addition, due to the improvements of control accuracies for the chemical dosing processes, the chemical dosages are reduced on the premise of ensuring safe water. Thus, both of the human resource costs and material costs can be saved. The practical control results demonstrate the efficiencies of proposed methods.

scholarly journals Does the recycling of waste streams from drinking water treatment plants worsen the quality of finished water? A case assessment in China

2016 ◽  
Vol 17 (2) ◽  
pp. 597-605
Author(s):  
Zhiquan Liu ◽  
Yongpeng Xu ◽  
Xuewei Yang ◽  
Rui Huang ◽  
Qihao Zhou ◽  
...  
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Treatment ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Ammonia Nitrogen ◽  
Raw Water ◽  
Waste Streams ◽  
Filter Backwash Water

The overall purpose was to assess the feasibilities of recycling filter backwash water (FBWW) and combined filter backwash water (CFBWW) in a drinking water treatment plant in south China. The variations of regular water-quality indexes, metal indexes (Al, Mn and Cd), polyacrylamide and disinfection by-product indexes (trihalomethanes and their formation potentials) along with the treatment and the recycling processes were monitored. Results showed the recycling procedure caused increases of turbidity, total solids, ammonia nitrogen (NH3-N), permanganate index (CODMn), and dissolved organic carbon, Al, Mn and Cd concentrations in a mixture of raw water and FBWW or CFBWW compared to those in raw water. However, the recycling procedure had negligible impacts on the qualities of settled water and filtered water because most of the contaminants could be effectively removed by the conventional water treatment process. Although recycling did cause slight increases of NH3-N and CODMn levels in settled water and filtered water, the quality of finished water always conformed to Chinese standards for drinking water quality according to the surveyed indexes in the present study. Thus, it is appropriate to recycle waste streams in water-stressed areas if the source water is well managed and the water treatment processes are carefully conducted.

Objectives for optimization and consequences for operation, design and concept of drinking water treatment plants

2008 ◽  
Vol 8 (3) ◽  
pp. 297-304 ◽  
Author(s):  
A. W. C. van der Helm ◽  
L. C. Rietveld ◽  
Th. G. J. Bosklopper ◽  
J. W. N. M. Kappelhof ◽  
J. C. van Dijk
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Treatment ◽  
Organic Carbon ◽  
Water Cycle ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Operational Parameters ◽  
Regeneration Frequency ◽  
Water Treatment Plants

Optimization for operation of drinking water treatment plants should focus on water quality and not on environmental impact or costs. Using improvement of water quality as objective for optimization can lead to new views on operation, design and concept of drinking water treatment plants. This is illustrated for ozonation in combination with biological activated carbon (BAC) filtration at drinking water treatment plant Weesperkarspel of Waternet, the water cycle company for Amsterdam and surrounding areas. The water quality parameters that are taken into account are assimilable organic carbon (AOC), dissolved organic carbon (DOC) and pathogens. The operational parameters that are taken into account are the ozone dosage and the regeneration frequency of the BAC filters. It is concluded that ozone dosage and regeneration frequency should be reduced in combination with application of newly developed insights in design of ozone installations. It is also concluded that a new concept for Weesperkarspel with an additional ion exchange (IEX) step for natural organic matter (NOM) removal will contribute to the improvement of the disinfection capacity of ozonation and the biological stability of the produced drinking water.

scholarly journals Autonomous intake selection optimisation model for a dual source drinking water treatment plant

2017 ◽  
Vol 18 (1) ◽  
pp. 279-287 ◽  
Author(s):  
E. Bertone ◽  
K. O'Halloran ◽  
M. Bartkow ◽  
K. Mann
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Treatment ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Data Driven ◽  
Water Utility ◽  
Drinking Water Treatment Plant ◽  
Optimisation Model

Abstract The Mudgeeraba drinking water treatment plant, in Southeast Queensland, Australia, can withdraw raw water from two different reservoirs: the smaller Little Nerang dam (LND) by gravity, and the larger Advancetown Lake, through the use of pumps. Selecting the optimal intake is based on water quality and operators' experience; however, there is potential to optimise this process. In this study, a comprehensive hybrid (data-driven, chemical, and mathematical) intake optimisation model was developed, which firstly predicts the chemicals dosages, and then the total (chemicals and pumping) costs based on the water quality at different depths of the two reservoirs, thus identifying the cheapest option. A second data-driven, probabilistic model then forecasts the volume of the smaller LND 6 weeks ahead in order to minimise the depletion and spill risks. This is important in case the first model identifies this reservoir as the optimal intake solution, but this could lead in the long term to depletion and full reliance on the electricity-dependent Advancetown Lake. Both models were validated and proved to be accurate, and with the potential for substantial monetary savings for the water utility.

scholarly journals Use of Acorn Leaves as a Natural Coagulant in a Drinking Water Treatment Plant

Water ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 57 ◽  
Author(s):  
Abderrezzaq Benalia ◽  
Kerroum Derbal ◽  
Antonio Panico ◽  
Francesco Pirozzi
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Treatment ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Distilled Water ◽  
Raw Water ◽  
Turbidity Removal ◽  
Leaf Powder

In this study, the use of acorn leaves as a natural coagulant to reduce raw water turbidity and globally improve drinking water quality was investigated. The raw water was collected from a drinking water treatment plant located in Mila (Algeria) with an initial turbidity of 13.0 ± 0.1 NTU. To obtain acorn leaf powder as a coagulant, the acorn leaves were previously cleaned, washed with tap water, dried, ground and then finely sieved. To improve the coagulant activity and, consequently, the turbidity removal efficiency, the fine powder was also preliminarily treated with different solvents, as follows, in order to extract the coagulant agent: (i) distilled water; (ii) solutions of NaCl (0.25; 0.5 and 1 M); (iii) solutions of NaOH (0.025; 0.05 and 0.1 M); and (iv) solutions of HCl (0.025; 0.05 and 0.1 M). Standard Jar Test assays were conducted to evaluate the performance of the coagulant in the different considered operational conditions. Results of the study indicated that at low turbidity (e.g., 13.0 ± 0.1 NTU), the raw acorn leaf powder and those treated with distilled water (DW) were able to decrease the turbidity to 3.69 ± 0.06 and 1.97 ± 0.03 NTU, respectively. The use of sodium chloride solution (AC-NaCl) at 0.5 M resulted in a high turbidity removal efficiency (91.07%) compared to solutions with different concentrations (0.25 and 1 M). Concerning solutions of sodium hydroxide (AC-NaOH) and hydrogen chloride (AC-HCl), the lowest final turbidities of 1.83 ± 0.13 and 0.92 ± 0.02 NTU were obtained when the concentrations of the solutions were set at 0.05 and 0.1 M, respectively. Finally, in this study, other water quality parameters, such as total alkalinity hardness, pH, electrical conductivity and organic matters content, were measured to assess the coagulant performance on drinking water treatment.

Sign in / Sign up

Export Citation Format

Share Document