This publication describes oncethrough and open recirculating systems. Control of the concentration of chemicals in the boiler water by bleeding off a portion of the water from the boiler. Suezs combination of cooling tower treatment chemicals, software, monitoring and. A basic understanding of the system water distribution shall be established in order to properly operate and maintain a cooling tower on a water. Fouling in cooling systems occurs by four potential processes, viz. The corrosion processes that could occur due to a bad cooling water. Alternative water treatment technologies for cooling tower. Gases including sulphur dioxide and ammonia, chlorine etc.
Recirculating cooling water systems are found in most air conditioning chiller operations, as well as many heat exchange operations. Audit and assessment cooling water pretreatment chemical applications monitoring before effective treatment can be provided, a thorough assessment of conditions in your cooling water system must be made. A comprehensive cooling water treatment program using. Systemvolume range 500 2000 m makeupwater often above 100 m. As the universal solvent, water is capable of dissolving a variety of materials as well as holding. Biofilm provides an environment for its rapid growth, then releases it into bulk water. Cooling water systems usually involve low head pumping plants, and often large flow rates, and aim to minimise the power costs for overall plant efficiency.
Select a treatment system if source quality is problematic. Have a cooling water treatment company analyze the chemical composition of the makeup water and prescribe a specific water treatment program for your makeup water and usage. Ozone treatment of cooling tower water is not feasible in all situations and hence traditional chemical treatment of cooling tower water is the only alternative. From the sump cool water is pumped back to the heat exchanger. To realize potential savings it is essential for federal agencies understand the key components of cooling towers and how to improve water efficiency of the system as a part of a comprehensive approach to water. One of our most useful resources is the mechanism of threshold treatment. The most common problems are the occurrence of scale.
Water drains from the bottom layer of the filter tank via a perforated tube and is led to a clean waterstorage tank. External treatment most of the unit operations of water treatment table 39. What is a cooling tower water treatment system and how. Technical reference for water conservation in cooling towers 1st edition. For industrial companies using a cooling tower for its facility, some type of cooling tower water treatment system is usually necessary to ensure an efficient process and long equipment service life. Cooling towers can be a significant source of water use for both of these categories of water use at federal facilities. Electrochemical water treatment for cooling towers nrel. But in reality, water related problems rob you of these savings and compromise the reliability of your cooling. Technical information for cooling towers using recycled water.
Best management practice and guidance manual for cooling towers. Technical reference for water conservation in cooling towers. A cooling tower functions to cool a circulating stream of water. Adding chemical treatment inhibitors to open recirculating cooling water systems provides an array of protection to the cooling water.
Chemical treatment of water for cooling and heating systems. Depending on the quality of available fresh water supply, waterside problems develop in cooling water systems from. Yet, failures due to inadequate water treatment and chemistry control, whether they be in the steam generator or cooling system, can cost a. Overview cooling water problems and solutions scale corrosion fouling biological problems total cooling. Treatment of cooling water will be different depending upon the kind of system in use. Selection of water treatment program for a specific system depends on. Legionella is a major cooling water treatment control issue. The open recirculating loop of the cooling system is comprised of the cooling tower and piping to and from the chiller or heat exchanger. Water is used in cooling systems as a heat transfer medium and frequently also as the final point to reject heat into the atmosphere by evaporating inside cooling towers. Guides and recommended procedures for water treatment.
These guidelines focus specifically on evaporative cooling units. Basic cooling water treatment treatment can be divided into four steps. In regions where potable supply is plentiful, cooling towers use potable water for making up the water losses in the cooling. An assortment of formulas for the protection of cooling water systems possibly supplemented with zinc at the corrosive end of the spectrum and high performance polymers at the scaling end. Establish the desired cycles of concentration to minimize water and chemical use, without. Water treatment for cooling towers 1 of 2 water treatment helps ensure that heattransfer surfaces perform to design specifications by amanda meitz, senior microbiologist, nalco diversified technologies, inc. External treatment most of the unit operations of water treatment. Best management practice and guidance manual for cooling. Control of ph is critical for the majority of cooling water treatment programs. It is used in cooling tower treatment chemicals for corrosion inhibition or as a tracer to determine the. Treatment of the boiler feed water, boiler water, steam, or condensate with corrective chemicals. When we use water to lower the operating temperature of equipment or entire plants, it is called cooling water. Cooling water problems and solutions ced engineering. French creek software is a leader in this technology, and many of the major water treatment chemical.
Many installations face problems with cooling systems related to water treatment. The fundamentals of water treatment technology a training workshop for stasmo presented by. Makeup water water added to the system to replace water lost through evaporation, bleed of and windage recirculation the rate at which water circulates in the cooling tower in m 3 hour litressec bleed off water deliberately bled from the system to prevent the cooling system water. The most commonly used are found in refrigeration and airconditioning systems where chilled water is circulated from the chiller to the air handling equipment. Water treatment the purpose of a cooling tower is to remove the heat generated by an hvac system cooling of compressor refrigerant and heat generated by the compressor itself. Cooling is accomplished through the latent heat of vaporization. Chapter 25 deposit and scale control cooling system. Pdf general water treatment for cooling water gerard. In general, when ph points to acidic environment, the chances for corrosion increase and when ph points to alkaline environment. The most commonly used are found in refrigeration and airconditioning systems where chilled water. This document is based on the practical experience of chemical engineers working in the field in the main. To make all parts of a cooling water system work perfect together, a good cooling water treatment. Our treatment program starts with an assessment of the process, water chemistry, cooling requirements, and metallurgy in your industrial cooling system.
The fan at the top of the tower induces a draft, which causes water evaporation and cooling. Industrial cooling tower and closed loop efficiency can be adversely. Treatment and corrosion control of cooling water page 5 the main chemical factors which influence the tendency of cooling water to corrode are mineral salt content, ph value and dissolved gases, notably oxygen and carbon dioxide. An introduction to cooling tower water treatment cedengineering. There are three basic types of cooling water systems.
The program should include routine analysis of the recirculating cooling water. Sufficient information is included in this paper for a water treatment engineer to design, manufacture, and apply scale and corrosion control remedies throughout a wide range of conditions. Cooling water treatment biofouling, lime scale and. Corrosion, deposition, fouling, and biological growth can derail your operations. System design, including system capacity, cooling tower type, basin depth. Sodium chlorite cooling water treatment with chlorine dioxide. If cooling tower water is left untreated, organic growth, fouling, scaling, and corrosion can reduce plant productivity, cause plant downtime, and require costly. Cooling water treatment we understand that your productivity and product quality could be impacted by the cooling water system. There is no single method of treating cooling water. Weve helped over 4,000 commercial, institutional, and industrial facilities with proven water treatment.
Usually this consumers are some kind of heat exchangers. Treatment and corrosion control of cooling water page 5 the main chemical factors which influence the tendency of cooling water to corrode are mineral salt content, ph value and dissolved. Due to the nature of evaporative cooling units, water lost from evaporation and blowdown has to be replenished. The operating personnel involved in the water treatment program come from various trade backgrounds and.
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