Test method for evaluation of anti-scale devices for cooling condensers

2004 ◽  
Vol 49 (2) ◽  
pp. 161-168
Author(s):  
J.B. Vestergaard
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Water Systems ◽  
Test Method ◽  
Cooling Towers ◽  
Germination Time ◽  
Air System ◽  
Closed Systems ◽  
Local Water ◽  
Drinking Water Systems

Can new types of anti-scaling devices prevent scaling on condensing pipes in industrial cooling condensers and supersede conventional water treatment? To examine this question a test method has been developed, test rigs have been built and different kinds of anti-scale devices have been tested. As cooling towers are based on an open-air system with evaporation of water they will have higher demands on the effectiveness of the anti-scale devices compared to the closed systems which are typical drinking water systems in buildings. The test method is based on an open-air system. The rigs are mobile and can be used to give an indication of whether it is possible to treat the local water with an anti-scale device. The result of the test is a scaling rate and a germination time. In addition to these tests the anti-scale devices have been tested in the field at cooling condensers.

scholarly journals Procedure for Calculating the Calcium Carbonate Precipitation Potential (CCPP) in Drinking Water Supply: Importance of Temperature, Ionic Species and Open/Closed System

Water ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 42
Author(s):  
Camilla Tang ◽  
Berit Godskesen ◽  
Henrik Aktor ◽  
Marlies van Rijn ◽  
John B. Kristensen ◽  
...  
Keyword(s):  
Drinking Water ◽  
Calcium Carbonate ◽  
Open Source Software ◽  
Open Systems ◽  
Ionic Species ◽  
Water Systems ◽  
Carbonate Precipitation ◽  
Calcium Carbonate Precipitation ◽  
Closed Systems ◽  
Drinking Water Systems

The calcium carbonate (CaCO3) precipitation potential (CCPP) can predict the potential for corrosion and lime scaling in drinking water systems. CCPP can be calculated by different standards, but none of these consider all of the conditions in drinking water systems where temperatures can reach 100 °C and the water exchanges CO2 with the atmosphere. We provided and demonstrated a procedure for CCPP calculations using the open-source software PHREEQC with the phreeqc.dat database at temperatures relevant for drinking water systems (10–90 °C) and for open systems in equilibrium with atmospheric CO2. CCPP increased by 0.17–1.51 mmol/kg when the temperature was increased from 10 °C to 90 °C and increased by 0.22–2.82 mmol/kg when going from closed to open systems at 10 °C. Thus, CaCO3 precipitation may be underestimated if CCPP is only considered for the lower sample temperature and for closed systems. On the other hand, CCPP10 decreased by 0.006–0.173 mmol/kg when including the ionic species from the German DIN 38404-10 standard in addition to calcium, alkalinity and pH, indicating that all relevant ionic species should be included in CCPP calculations. CCPP values should always be reported with the calculation procedure and temperature to avoid inconsistency in literature.

Legionnaire’s disease and COVID-19: Could Legionella be acting in conjunction with the Corona virus to aggravate the COVID-19 disease?

2020 ◽  
Author(s):  
Andrew John PENDERY
Keyword(s):  
Drinking Water ◽  
Air Conditioning ◽  
Water Systems ◽  
Contaminated Water ◽  
Cooling Towers ◽  
Age Group ◽  
Corona Virus ◽  
The Usa ◽  
Legionnaire's Disease ◽  
Legionnaire’S Disease

There are some striking similarities between Legionnaire’s disease and COVID-19. Thesymptoms, age group and sex at risk are identical. The geographical distribution of both diseases is similar in Europe overall, and within the USA, France and Italy. The environmental distributions are also similar. However Legionnaire’s disease is caused by Legionella bacteria while COVID-19 is caused by the Corona virus. Whereas COVID-19 is contagious, Legionnaire’s disease is environmental. Legionella bacteria are commonly found in drinking water systems and near air conditioning cooling towers. Legionnaire’sdisease is caught by inhaling contaminated water droplets. The Legionella bacteria does not spread person to person and only causes disease if it enters the lungs.Could the Corona virus be making it easier for Legionella bacteria to enter the lungs?

scholarly journals The Water Safety Plan Approach: Application to Small Drinking-Water Systems—Case Studies in Salento (South Italy)

2021 ◽  
Vol 18 (8) ◽  
pp. 4360
Author(s):  
Francesca Serio ◽  
Lucia Martella ◽  
Giovanni Imbriani ◽  
Adele Idolo ◽  
Francesco Bagordo ◽  
...  
Keyword(s):  
Drinking Water ◽  
Case Studies ◽  
Distribution Systems ◽  
Water Systems ◽  
Water Safety ◽  
Quality Of Water ◽  
Safety Plan ◽  
Water Safety Plan ◽  
Drinking Water Systems

Background: The quality of water for human consumption is an objective of fundamental importance for the defense of public health. Since the management of networks involves many problems of control and efficiency of distribution, the Water Safety Plan (WSP) was introduced to address these growing problems. Methods: WSP was applied to three companies in which the water resource assumes central importance: five water kiosks, a third-range vegetable processing company, and a residence and care institution. In drafting the plan, the terms and procedures designed and tested for the management of urban distribution systems were applied to safeguard the resource over time. Results: The case studies demonstrated the reliability of the application of the model even to small drinking-water systems, even though it involved a greater effort in analyzing the incoming water, the local intended use, and the possibilities for managing the containment of the dangers to which it is exposed. This approach demonstrates concrete effectiveness in identifying and mitigating the dangers of altering the quality of water. Conclusions: Thanks to the WSP applied to small drinking-water systems, we can move from management that is focused mainly on verifying the conformity of the finished product to the creation of a global risk assessment and management system that covers the entire water supply chain.

scholarly journals Occurrence of Lead and Other Toxic Metals Derived from Drinking-Water Systems in Three West African Countries

2021 ◽  
Vol 129 (4) ◽  
Author(s):  
Michael B. Fisher ◽  
Amy Z. Guo ◽  
J. Wren Tracy ◽  
Sridevi K. Prasad ◽  
Ryan D. Cronk ◽  
...  
Keyword(s):  
Drinking Water ◽  
Toxic Metals ◽  
Water Systems ◽  
West African ◽  
African Countries ◽  
Drinking Water Systems

scholarly journals Disinfection exhibits systematic impacts on the drinking water microbiome

2019 ◽  
Author(s):  
Zihan Dai ◽  
Maria C. Sevillano-Rivera ◽  
Szymon T. Calus ◽  
Q. Melina Bautista-de los Santos ◽  
A. Murat Eren ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Distribution ◽  
Microbial Growth ◽  
Glyoxylate Cycle ◽  
Water Systems ◽  
Chemical Compositions ◽  
Functional Potential ◽  
Decay Products ◽  
The Impact ◽  
Drinking Water Systems

ABSTRACTLimiting microbial growth during drinking water distribution is achieved either by maintaining a disinfectant residual or through nutrient limitation without the use of a disinfectant. The impact of these contrasting approaches on the drinking water microbiome is not systematically understood. We utilized genome-resolved metagenomics to compare the structure, metabolic traits, and population genomes of drinking water microbiomes across multiple full-scale drinking water systems utilizing these two-distinct microbial growth control strategies. Microbial communities cluster together at the structural- and functional potential-level based on the presence or absence of a disinfectant residual. Disinfectant residual concentrations alone explained 17 and 6.5% of the variance in structure and functional potential of the drinking water microbiome, respectively, despite including samples from multiple drinking water systems with variable source waters and source water communities, treatment strategies, and chemical compositions. The drinking water microbiome is structurally and functionally less diverse and less variable across disinfected systems as compared to non-disinfected systems. While bacteria were the most abundant domain, archaea and eukaryota were more abundant in non-disinfected and disinfected systems, respectively. Community-level differences in functional potential were driven by enrichment of genes associated with carbon and nitrogen fixation in non-disinfected systems and γ-aminobutyrate metabolism in disinfected systems which may be associated with the recycling of amino acids. Metagenome-assembled genome-level analyses for a subset of phylogenetically related microorganisms suggests that disinfection may select for microorganisms capable of using fatty acids, presumably from microbial decay products, via the glyoxylate cycle. Overall, we find that disinfection exhibits systematic and consistent selective pressures on the drinking water microbiome and may select for microorganisms able to utilize microbial decay products originating from disinfection inactivated microorganisms.

scholarly journals Detection of Microcystins in Lake Manatee and Lake Washington – Two Florida Drinking Water Systems

2021 ◽  
Author(s):  
Rajesh Melaram ◽  
Brandon Lopez-Dueñas
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Surface Water Quality ◽  
Well Being ◽  
Water Systems ◽  
Enzyme Linked Immunosorbent Assay ◽  
Water Supplies ◽  
Intrinsic Nature ◽  
Lake Washington ◽  
Drinking Water Systems

Clean, fresh, and safe drinking water is essential to human health and well-being. Occasionally, chemical pollutants taint surface water quality used for consumption. Microcystins (MCs) are toxic heptapeptides produced by freshwater cyanobacteria. These secondary metabolites can reach hazardous concentrations, impairing surface drinking water supplies. Inconsistent screening of MCs is not uncommon in Florida waters as no provisional guidance value is established to protect public health. The occurrence of MCs in Lake Manatee and Lake Washington was monitored over the potential peak algae bloom season (June-August). An indirect competitive enzyme-linked immunosorbent assay (icELISA) quantified total MCs in two drinking water systems. Varied concentrations occurred between June and July, whereas concentrations peaked in August. Overall, MC prevalence was higher in Lake Manatee than Lake Washington. Colorimetric assays measured phosphate and nitrite in environmental water samples. Phosphate and nitrite concentrations strongly correlated with total MCs (p < 0.01). The results indicate the intrinsic nature of environmental MCs in surface drinking water supplies and the need to examine hepatotoxin dynamics to preserve drinking water quality in community served areas.

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