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Drinking Water Industry

Drinking Water Industry
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Drinking Water Industry Solutions Safe and Reliable Liquid Analysis ROSEMOUNT EMERSON Analytical Process Management

TRUSTED EVERY WHERE: THE MOST ADVANCED LIQUID ANALYSIS SOLUTIONS WE START WITH ONE IDEA: MAKE IT SAFE Water is the most crucial element needed for human activity on the planet, including agricultural, industrial and domestic use. Unfortunately, water quality around the world is poor and getting worse. While over 70% of the Earth is covered in water, only about 0.01% is usable fresh water. And since water demand increases with population, the re-use of water and proper treatment methods have become a critical necessity. Poor Water Quality: Understanding the Problem Water treatment plants...

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DRINKING WATER TREATMENT OVERVIEW Primary Disinfection (Ozone or Chlorine Treatment) Plant Intake Flash Mixers Filter Wastewater Backwash Flocculation Basin Settling Basin Filter Beds Secondary Disinfection Chlorine Addition (Ammonia Addition) Page 7 Water Tower Clear Well Homes To Distribution System Page 8 Booster Station Here’s a typical drinking water measurement of ozone and/or plant. It takes water from a lake, chlorine. Particles are removed river or well and treats it through primary disinfection, coagulation, continuous turbidity Primary Disinfection ondary disinfection to purify...

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PRIMARY DISINFECTION To better define the dynamics of the raw water source being used by a treatment plant, a number of liquid analytical measurements are made prior to entering the treatment process. Influent monitoring measurements could include pH, conductivity, temperature, turbidity, dissolved oxygen, and Total Organic Carbon (TOC). Some plants also keep a permanent record of each of these measurements for future reference or for detecting seasonal changes in the source water. Since water is a universal solvent, Oxidation Potential (volts) it comes in contact with several different...

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COAGULATION, FLOCCULATION AND SEDIMENTATION After pretreatment and primary disinfection, the clarification of raw water is usually a multiple step process for reducing turbidity and suspended solids. Coagulation and Focculation Smaller particles combine or coagulate into larger fluffy particles called floc and settle out of the raw water source as sediment. The coagulation process is promoted by the addition of chemical coagulant such as alum, iron salts or synthetic organic polymers. After chemical addition, the water flows through a mixing channel where the water and chemicals are flash...

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LIME IN WATER TREATMENT Lime is used by many municipalities to improve water quality, especially for water softening and arsenic removal. In terms of annual tonnage, lime ranks first among chemicals used in the treatment of potable and industrial water supplies. Lime has multiple applications: pH Adjustment/Coagulation Hydrated lime is widely used to adjust the pH of water to prepare it for further treatment. Lime is also used to combat "red water" by A Model 3900 pH sensor – available with SMART capabilities. neutralizing the acid water, thereby reducing corrosion of pipes and mains from...

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removes particles 25 microns Light Source Tungsten Lamp LED or Tungsten Lamp Characteristics Long WarmUp Time required. The turbidity is enters the filtration stage. The filtration stage also removes residual matter resulting from the oxidation of organic chemicals and microorganisms in the primary disinfection stage. Finally, microorganisms resistant to chlorine or ozone disinfection in the pretreatment stage are effectively removed during filtration. Periodically, the filter must be back washed to remove the fine suspended matter and accumulated sediment that collects in the filter media....

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SECONDARY DISINFECTION In compliance with the regulations requiring post residual disinfection, plants use chlorination as secondary disinfection in the final treatment step. Ozone does not provide germicidal or a longlasting disinfection residual to inhibit or prevent re-growth of pathogens in the water distribution system. Model TCL Total Chlorine Sample Conditioning System the re-growth of certain pathogens that may enter the treatment plant or be introduced by backflow contamination. When chlorine is added to water, free chlorine forms a mixture of hypochlorous acid (HOCl) and...

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FINAL TREATMENT The U.S. specifies the optimal level of fluoride to range from 0.7 to 1.2 mg/L (milligrams per liter, equivalent to parts per million), depending on the average maximum daily air temperature; the optimal level is lower in warmer climates, where people drink more water, and is higher in cooler climates. The Centers for Disease Control and Prevention have developed recommendations for water fluoridation that specify requirements for personnel, reporting, training, inspection, monitoring, surveillance, and actions in case of overfeed, along with technical requirements for each...

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FINAL TREATMENT continued climates. Fluoride ISE measuring systems are complete systems that measure fluoride ion activity and are available in single or dual panels. where it’s difficult to keep acceptable chlorine levels, this might be a direct result of biological growth and nitrification. Many water systems already have ammonia in their water or add ammonia during their treatment process. Excess free ammonia in water distribution systems promotes biological growth and nitrification. If the system experiences isolated areas of water quality degradation that affect the aesthetic quality...

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DISTRIBUTION MONITORING The prevention of contamination in the distribution system, thereby reducing the risk of water borne diseases, requires regular monitoring for disinfectant levels, microbial levels, and corrosion products. Although water may be safe upon leaving the treatment plant, it is important to monitor for contamination by growth of microorganisms, pressure problems, and water main breaks. Monitoring can also indicate formation of biofilms, malfunctioning piping and valves or other threats to the system. Because pathogens can enter the distribution system through cracks and...

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