Your personalized homepage experience is available here. Routine testing of conductivity, pH or alkalinity, and inhibitor level is used to determine if there has been any . The major benefits of these are cost-effectiveness, as well as outright effectiveness through significantly colder cooling water delivered to process. The coolant used in a closed-loop chiller can include: Water and water-based coolants (de-ionized water, water/glycol mix, water-based synthetic coolants) 4.4 4.4 out of 5 stars (314 . As the name suggests, closed-loop HVAC systems are sealed units containing a fixed volume of water. Closed heating and cooling water systems typically require little makeup water and minimal chemical additions following the initial system charge. We have water treatment professionals who know the right way to balance the water chemistry in your system. To keep the correct chemical balance, water treatment professionals have several options at their disposal: These substances are not the only options for maintaining a closed loop system, but they are a sampling of the products maintenance professionals could use. The control of biological agents, like bacteria and algae, is vital to any effective cooling water treatment. Through these complex, industrial constructs, this high temperature is regulated quite efficiently and both the, The reason why this method is so popular is due to the fact that its a natural cooling system, which uses direct contact with fresh air to cool the hot water from the system. 3D TRASAR technology for cooling water systems can help you reach your sustainability goals by reducing . . There are three main types of closed-loop cooling systems: closed-loop dry systems, closed-loop evaporative systems, and liquid-to-liquid cooling systems. Closed-loop systems that use demineralized water makeup would tend to be on the lower end of this range. As shown, the molybdate-based treatment provides the best overall steel and Admiralty protection. Explore five specific ways you can use less water in your facility below. help you have the best experience while on the site. Heavy-duty finned-tube condensers deliver high efficiency and long service life in hot, corrosive, or dirty ambient environments. Corrosion is an electrochemical event in which a destructive interaction occurs between a metallic surface and non-metallic environment. Some closed systems, such as chilled water systems, operate at relatively low temperatures and require very little makeup water. Overheating of stator bars can result in reduced generating capacity or even catastrophic failure of the generator. Closed cooling water system To cool key processes in petrochemical plants, refineries, power plants and other heavy-duty industrial environments, many plant owners and operators rely on closed-loop cooling as the preferred cooling method. Their main trait is that theyre pre-designed, built completely in a factory, and transported to the target location. Specific equipment such as cooling towers, boilers and closed loop systems can use less water than they currently do. The ends of the stator bars are often bent to fit the generator configuration. This produces a general, but overall low level of corrosion. All of this is achieved with the help of power-driven fans, which classify this cooling system type as mechanical. By visiting this website, certain cookies have already been set, which you may delete and block. There is no thing as a perfect closed-loop system, which means that such industrial activities as hot-water heating and cooling-water recirculation require assistance in order to prevent the scale buildup, corrosion and biological growth that can foul the system and hamper its operational capabilities. Copyright 2023. Make sure unit is level. Mechanical draft cooling is an industrial cooling water system, which involves the use of an evaporation process for cooling. In some cases, oxygen leaks in through a loose connection or flange that creates a venturi effect, sucking air in. The bearing cooling water system generally provides cooling for critical pump bearings and seals, hydrogen coolers for the generator, lube oil, and air compressor coolers. . Common types of equipment that may use OTC includes commercial and industrial air conditioners, wok stoves, walk-in cooler and freezes, and ice machines. Some facilities require generators to keep the lights on, whereas others need an emergency cooling system to continue process and component cooling if the primary mechanism fails. We mold the entire casing of the cooling tower as one piece so there are no joints or seams to require maintenance or develop leaks. A significant change in the dissolved oxygen changes the electrochemical potential of the water. This further encourages some types of bacteria, as they use the oxidized metal in their metabolism. The copper corrosion rate can be very low, but conditions that accelerate the rate at which the copper oxide is released into the water can be very detrimental to the condition of the system. In the closed-loop chiller, the coolant is first chilled in a coolant tank, then circulated throughout the process/equipment; during this circulation, the coolant absorbs heat from the application and equipment. Offering Water Treatment Chemicals & Services to Commercial, Industrial, Property Management Business & More In: Legionella Testing, Control & Water Management Plans, Importance of Water Treatment for Closed Loops, What Happens when Microbiological Growth Goes Unchecked, Industries that use Closed Loop Technology, Closed Loop Water Treatment for Industrial Emergency Systems, Industrial Applications of Closed Loop Systems, keeps the water completely enclosed inside pipes, is black magnetic iron oxide mud deposits, Lowered pH could indicate bacterial growth, cooling for safety and non-safety components, Reducing the contaminants and debris in the system, What Corrosion Coupons are & Their Importance, How to Optimize the pH Balance of Cooling Tower Water, A Solution Focused Chemical Water Treatment Company, Chemical Water Treatment Services for Your Industry. Anti-corrosion Aqueous solutions can cause corrosion on metals or alloys found in water treatment systems. Nonmetallic components, such as natural or synthetic rubber, asbestos, and carbon, are also used. Thanks to multiple cooling paths, the parts of a plant remain at a safe operating temperature. Either of these oxides can be stable and create a passive oxide layer on the channels in the stator bars. Nitrite is another widely accepted nonchromate closed cooling water inhibitor. It is important to understand that it is not necessarily the corrosion of the stator bar per se that creates the problems. Please enable JavaScript on your browser and try again. A closed-loop process-cooling system constructed of corrosion-resistant materials categorically prevents the introduction of contaminants to process water and is the single most effective way to forestall avoidable equipment deterioration. A closed-loop cooling system is a cooling system that uses a liquid coolant (which can be water/water-based coolants or oil/oil-based coolants) to exchange heat from the industrial process in a closed-loop setup. The stator cooling water system is a very special closed loop for a couple of reasons. Still, every scenario is unique in its own way and you can contact us today to learn more about our, Closed-Loop System with Plate Heat Exchanger, Closed-Loop System with Shell & Tube Exchanger. Many industries use these for process cooling. Aside from emergency use, closed circuit cooling systems also serve to cool down components at a power plant. There is only one metal of concern in this system: copper. In very high heat transfer rate applications, such as continuous caster mold cooling systems, chromate levels should be maintained at 100-150 ppm maximum. In the meantime, critical data equipment may be damaged to the point where it affects the ability of the plant to operate. Some of the concerns with closed loop systems are corrosion, scale, particulate and microbiological growth. The metallurgy used in constructing modern engines, compressors, and cooling systems includes cast iron, steel, copper, copper alloys, and aluminum as well as solders. However, once corrosion processes get a foothold in these systems, it can be very difficult to correct them. Operating a lowdissolved oxygen regime requires that the stator cooling water always maintain less than 20 ppb of dissolved oxygen, and ideally as low as possible. These chillers use various kinds of coolant, including water, glycol and oil-based coolants. Closed systems are also less susceptible to biological fouling from slime and algae deposits than open systems. excellent customer service, we're Pfannenberg, Inc., a leading global manufacturer of thermal management and signaling technologies, highlights its high-efficiency liquid cooling solutions for industrial electronics. And this system must remain very clean, even pristine. Nonchromate inhibitors are compatible with typical antifreeze compounds. These industrial cooling systems are critical to have 100% uptime to not stop the production line within the facility. Common applications where a circulating water pump is used include cooling systems . This cycle can cause a stator cooling problem to come out of nowhere. MIcrobiological corrosion in a closed loop system can become a serious problem in a very short time and should be addressed immediately. These systemscan be configured into a variety of different systems depending on the cooling requirements of the system. Monitoring and Treatment of Closed-Loop Cooling Water Systems. Any particles that are trapped by the filters or by the deionization resins are particles that cannot reattach to the surface of the stator cooling channel. Chromate treatments in the range of 500-1000 ppm as Cr4O2are satisfactory unless bimetallic influences exist. Terms of Service One of the advantages of this treatment is that it is thought to be very environmentally benign, although as long as the closed-loop system remains closed, there should be no impact on the environment. Some plants put carbon dioxide absorbers on the head tank vent to remove it, before the air enters the tank. There are often two deionizer vessels and two sets of filters to allow one to be valved out to replace the filter cartridge or for replacement of the mixed-bed resins. Many times these systems are neglected since leaks take time to develop. Where circulating pumps are equipped with certain mechanical seals, such as graphite, chromate concentrations may not exceed 250 ppm. The benefits of closed-loop chillers are multifold: There are three main types of closed-loop cooling systems: closed-loop dry systems, closed-loop evaporative systems, and liquid-to-liquid cooling systems. The best way to avoid problems of copper corrosion and keep the stator bars flowing and cool is to know what treatment option you are going to use and to monitor the stator water-cooling system appropriately. cooling systems usually consist of a closed-loop recirculating system to cool the power supply, heat station, coils, bus, and leads. Compact, efficient and flexible, they can easily be adapted to accommodate changes in capacity. A chilled water system's refrigeration cycle works by removing heat from chilled water in the evaporator of the chiller. Industrial process cooling with innovative solutions that determine an increase in productivity with minimum environmental impact. Care and keeping of these systems requires that you pay attention to all the metals. This big cathode, little anode configuration causes concentrated and accelerated pitting in a confined area, producing pinhole leaks. www.watertechonline.com is using a security service for protection against online attacks. OTC systems can be big water wasters. They are hybrids that pass the working fluid through a tube bundle, upon which clean water is sprayed and a fan-induced draft applied. Generally, you find a treatment program that works well for the various metals in your system and system requirements (for example, determine if you need freeze protection) and then stick with it. If the closed-loop system becomes contaminated with these bacteria, the nitrite level can decrease rapidly. Other closed recirculating cooling applications include smelt spout cooling systems on Kraft recovery boilers and lubricating oil and sample coolers in power plants. Some success has also been recorded with nitrite-based treatment of closed brine systems at treatment levels of about 2000 ppm as. To provide a more consistent flow of cooled water than other heat sinks for water, these have a built-in pump and reservoir. This website requires certain cookies to work and uses other cookies to Other similar closed loop systems are used near the beverage chillers for more efficient, more tightly controlled cooling for each separate process. Using a cooling water treatment can reduce the heat wear on these components, and a closed loop system cools while requiring less maintenance. Chillers. Depending on the current condition of the water, as they reattach, the deposits may contain either of the two copper oxides mentioned above or copper metal. Sodium nitrite has been in use for many years to prevent corrosion in a wide variety of closed-loop systems. Dont neglect your closed loop water system. Factors like new water piping, cooling cycles, and water recycling processes can offset the efficiency of cooling systems drastically. Currently, we have 25wt% glycol water in the systems. replacing nitrite with molybdate to alleviate nitrifying bacteria problems. An appropriate inhibitor such as nitrite or molybdate should be added to sufficient levels to maintain corrosion protection. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Learn more about Inductotherm Group and our 40 companies around the world. An analysis should be performed to identify existing or future or problems within the system. and cookie policy to learn more about the cookies we use and how we use your A slightly alkaline pH increases the stability of either oxide layer. DEEPCOOL Castle 240EX - With RGB. This creates two separate fluid circuits: (1) an external circuit, in which spray water circulates over the coil and mixes with the outside air, and (2) an internal circuit, in which the process fluid to be cooled circulates inside the coil. Depending on the pressure of the closed-loop versus open-loop system at this point, the bearing cooling water may leak out, or the open cooling water may leak in. If bacteria are allowed to propagate inside the closed-loop system, they can create a living deposit. We want to help you get a clean system that will last. Lowering the pump speed can conserve energy when cooling needs decrease. Some smaller variants come in the form of rooftop units. Treating the water to prevent corrosion and freezing is part of maintaining these systems. The flexibility to adjust to cooling and energy needs makes closed loop systems more energy efficient. Minimize your system energy, maintenance, and installation costs with the FXV Closed Circuit Cooling Tower, the industry standard for closed-loop systems. Polymer treatments have been used for many years to prevent scale and corrosion product accumulations in open cooling towers. While you should not cease all care for your system, closed circuit designs will require fewer checks throughout the year. Only see the articles on the blog you are interested in reading. This means that the decrease in temperature is rapid, reliable, and as effective as it gets. Closed-Loop Cooling Systems 101 By HydroThrift Corp. Dry, evaporative and liquid-to-liquid cooling systems are explained. Closed-loop chillers are used to exchange heat from industrial or commercial applications by running coolant through a closed-loop system. What Causes Liquid Ring Pump Cavitation and How To Prevent It? Chilled water systems (air chillers) exchange heat with the compressor, which in turn uses a cooling tower to throw heat back into the environment. Once the closed loop system begins operation,you will not see the results of corrosion until the system shows signs of failure. CEC coolers also eliminate the complications and expense of industrial effluent. These are erected on the spot (hence the name), but they also can be more expensive. The shape of the system is such that it naturally draws a draft into the tower, eliminating the need for a mechanical fan system with a propeller and motor. Drops in pH may indicate bacterial contamination, particularly with the nitrite-based treatments. Over a long period, the addition of even small amounts of hard makeup water causes a gradual buildup of scale in cylinders and cylinder heads. Not a subscriber or a registered user yet? The compressor is what drives the entire process. This occurs because the lower solubility of oxygen with increasing temperatures in a freely vented system decreases the corrosion rate faster than the rise in temperature increases it. Improper treatment levels will always lead to corrosion of these systems. The slower the water travels through the stator bar, the warmer it becomes. As a precautionary measure, the resins should be changed every 18 months to two years. For instance, most food and beverage processing plants use open cooling towers for process chilling. The only make-up water normally needed is replace water loss from leakage at pump seals, expansion tank overflow, or surface evaporation from system vents. A closed loop water chiller system can be installed in any building, regardless of its size or age. That's why most water treatmentservices aim to prevent corrosion, scale and other microbiological growth. There is somewhat of a vicious cycle effect here. From our low maintenance design Closed loop water treatment is essential for many industrial emergency systems that rely on cooling water. If a freeze protection solution such asglycol is incorporated, freeze protection point and percentage glycol should be performed. This generates the Cu2O passive layer but over a longer period of time. The recommendation is to replace the demineralizer resins if the conductivity exceeds 0.5S/cm or if the pressure differential across the deionizer exceeds 15 psid. Compact Efficiency Easy Maintenance and Repair Rugged Protection while allowing for easy maintenance and wash down High Flow - Long Life - Dependable Rugged Dependability - Long Life Additional Specs: Chill Water Circuit - Stationary Flow 2-100 Ton (Single) Chill Water Circuit - Stationary Flow 2-100 Ton (Dual) Flushing removes any solid particles or debris so that cooling water system remains clean. In a previous article we discussed treatment options for stator cooling water in more detail (Forgotten Water: Stator Cooling Water Chemistry in the December 2007 issue of POWER). Before doing the chemical treatment of any water piping system the flushing is must. Compressor (HP) 5 - 15; Cooling Capacity (refrigeration tons) 4.6 to 14.6; Single circuited systems; Large Size Water Cooled Chiller. In part because they are closed-loop systems, it can be easy to ignore power plant cooling water systems that support the reliable functioning of everything from stator bars in the generator to critical pump bearings for feed pumps and heat exchangers on air compressors. Unfortunately, the world supply of molybdate metal tends to be concentrated in areas of historical political unrest, and over the years, molybdate prices have varied dramatically. By closing this banner, scrolling through this page or clicking on any of its elements, you allow us to use cookies. Whatever the active agent is in your treatment (nitrite, molybdate, or polymer) the concentration must be regularly monitored. Closed Loop Cooling Tower. Curve A plots data from a completely closed system with no provision for the venting of oxygen to atmosphere. It uses less energy and has a lower carbon footprint than air conditioning. The benefit of packaged towers is that theyre much simpler and quicker to install, can be modular for future expansion and dont carry the risk of field erection time and costs. In major industrial complexes, these mechanical draft cooling systems can be found in various shapes and sizes. (Your original equipment manufacturer may have different limits.). Consult with experts in the field. The pH should be 7.0-8.5 with caustic adjustment only. Industrial Water Chiller is a division of T. J. If you already have a closed loop system, youll feel you made a quality investment. In a system without any leaks, as long as water monitoring and treatment occur regularly, this scheduling should sufficeto minimize pollutants. Nitrite concentra-tions in the range of 600-1200 ppm as NO2-will suitably inhibit iron and steel corrosion when the pH is maintained above 7.0. The feed of nonoxidizing antimicrobial may be necessary to control nitrite reversion andbiological fouling. This is why these industrial cooling systems are manufactured from different materials to allow for higher temperature ranges and overall efficiency. Closed loop systems have more uses than for emergencies. -Deionized process cooling water, which can be either open or closed. A water chiller removes heat from the process water and transfers it to air via a heat exchanger. Heat, absorbed by the water in the closed system, is normally transferred by a water-to-water exchanger to the recirculating water of an open recirculating system, from which the heat is lost to atmosphere (Figure 32-1). Energy Costs = 100 kW 0.3 kW/kW 4,800 hours x $0.1 / kW-hour x 1.0 duty cycle = $14,400 per year. Water chillers are also used food & beverage applications like wineries and breweries. Nitrite-based treatment also provides effective steel protection, with results comparable to those obtained with molybdate; however, acceptable Admiralty corrosion inhibition is not achieved. There may be multiple closed-loop cooling systems at your power plant. During shutdown, oxygen can enter the water until its saturation limit is reached. Little, if any, evaporation occurs. A major consideration when considering mechanical. When efficient cooling is not at a premium and water savings is a must, these are a good fit. For cost-efficient and long-lasting closed-loop cooling, count on Alfa Lavals broad range of plate heat exchangers and filters for safe, reliable, effective and environmentally sound operations. This can cause the copper oxide to be converted from one form (cupric) to the other (cuprous). Cooling towers come in many sizes depending on the exact needs and amount of heat that must be removed . Deposits and partially plugged strands can reduce the water flow rate. Visit our updated. Of those power plants that have water-cooled stators, there is almost an even split of high- and low-oxygen regimes, with the slight numerical advantage to those operating in the highdissolved oxygen regime. Makeup water is needed only when leakage has occurred at pump packings or when water has been drained to allow system repair. There is no one-size-fits-all solution; the best water treatment programs are specifically tailored to meet . However, these dry cooling systems result in warmer cold water so they are not as efficient as mechanical open industrial cooling systems. Each tower includes a seamless exterior shell. In all cases, the pH of the circulating water should be maintained in the alkaline range, but below 9.0 when aluminum is present. This is a major problem in some of the worlds most efficient manufacturing plants and this is exactly what industrial cooling systems are. The closed loop evaporative system is an open tower with a closed-loop heat exchanger built into the tower. Small changes in the chemistry or the flow rates and differential pressures throughout the system may not be noticed. This means that your line of work may mandate the need for a specific tower type. Search for used industrial process cooling water pump stations & systems. Efficiency also increases in the winter when closed loop systems can operate dry, preventing freezing during the colder months. Mar 1, 2016. by POWER. Top 5 Best Closed Loop CPU Coolers. Under these extreme conditions, chromate can accumulate at the grain boundaries on the mold, causing enough insulation to create equipment reliability problems. Cold Plates Connect these plates to cold liquid lines in process chillers and liquid-to-air cooling systems to cool equipment through direct contact. In a typical dual-loop system, VIPPower Supply Unit cooling is achieved through a heat exchanger coupled to a furnace cooling tower loop. Even with the same system, you can make a massive difference by running the facility and the cooling system in a different way.