Common types of equipment that may use OTC includes commercial and industrial air conditioners, wok stoves, walk-in cooler and freezes, and ice machines. When hot or chilled water recirculates through a piping system with little to no makeup water it is known as a closed loop. Untreated systems can suffer serious corrosion damage from oxygen pitting, galvanic action, and crevice attack. Dry cooling is a bit different, seeing as how it uses mechanical means to cool the fluids by the air. A closed circuit system keeps the water completely enclosed inside pipes, preserving water volume and quality. The conductivity is critical and generally is kept below 0.5S/cm. Visit our updated. Because the carbon steel and copper corrosion treatment are typically blended into one product, low levels of treatment may affect more than just the carbon steel piping. Minimize your system energy, maintenance, and installation costs with the FXV Closed Circuit Cooling Tower, the industry standard for closed-loop systems. 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. The water in your cooling or heating system dramatically affects performance. Recommended treatment control limits are 200-300 ppm molybdate as MoO42. In some systems, nonoxidizing biocides such as glutaraldehyde or isothiazoline are added to the treatment to prevent bacterial growth. The CW system has traditionally been a constant flow (CF) system, but recently designs have included variable flow (VF) in this system as well. But before you request a quote, you should understand your system and why water treatment is vital to maintaining it. We wont sell you chemicals. Moreover, as weve mentioned, not all of these systems are made equal and some are standard for specific industries. If the new system contains excessive amounts of mill scale and acid based cleaner should follow the alkaline cleaning. The closed circuit has four ways to adapt to cooling needs and outside temperature changes: Adaptability makes closed systems a better option for variable climates, but ultimately the upkeep of the system will determine its cost over time. In a closed system, water circulates in a closed cycle and is subjected to alternate cooling and heating without air contact. In very high heat transfer rate applications, such as continuous caster mold cooling systems, chromate levels should be maintained at 100-150 ppm maximum. Neglecting the maintenance of a closed system promotes the growth of sludge and deposits. Routine testing of conductivity, pH or alkalinity, and inhibitor level is used to determine if there has been any . Snow Company) is recognized as a trusted source for these important, yet often overlooked process components. Curve A plots data from a completely closed system with no provision for the venting of oxygen to atmosphere. In a system without any leaks, as long as water monitoring and treatment occur regularly, this scheduling should sufficeto minimize pollutants. The closed loop water chiller system is a more efficient and sustainable way to cool buildings. The stator cooling water system is a very special closed loop for a couple of reasons. Closed loop systems have a reduced chance of contamination, but they are not maintenance-free. Effective pretreatment defends against the majority of closed loop system concerns. To provide a more consistent flow of cooled water than other heat sinks for water, these have a built-in pump and reservoir. For instance, most food and beverage processing plants use open cooling towers for process chilling. This process is automatic. Find out how we can help improve the thermal performance of your closed systems, lower energy bills, reduce maintenance costs and down-time, and extend plant life-cycles. The chemistry of copper in oxidizing and reducing conditions has been the subject of a great deal of research, and we have a better understanding now of the conditions that cause corrosion, which is a common problem. Closed-loop cooling systems provide clean, nonfouling, nonscaling, noncorrosive coolant for many types of industrial equipment and processes. Headquarters: 7300 Tussing Rd, Reynoldsburg, OH 43068 Nitrite- molybdate-azole blends inhibit corrosion in steel, copper, aluminum, and mixed-metallurgy systems. In closed systems that continuously run at temperatures below 32F (0C), a closed brine system is often employed. To prevent serious harm from untreated water, you need frequent treatment of the system and its contents. Withproper pre-cleaning and initialtreatment, a new system can continue to give good service decades after it is installed. Below is a brief method statement for doing cleaning, flushing and passivation of closed loop water cooling/chilling system, which is part of HVAC system of a building. We offer a diverse inventory of water chillers to properly cool your industrial process! DEEPCOOL Castle 240EX - With RGB. This analysis should include pH, conductivity, alkalinity, hardness, and iron. To prevent corrosion in carbon steel components, the water must maintain a high or alkaline pH. This website requires certain cookies to work and uses other cookies to Flushing and chemical pretreatment are necessary to keep bacteria, algae and fungi from proliferating on pipe surfaces. This site uses cookies to offer you a better browsing experience. Figure 5 shows copper oxides that have deposited out in a feather-like structure on the copper surface. Some plants put carbon dioxide absorbers on the head tank vent to remove it, before the air enters the tank. In order for oxygen pitting to occur, there must first be a deposit that covers a portion of the metal surface, creating a differential between the oxygen content underneath the deposit and the oxygen content in the bulk water. The ion exchange resins may also trap fine particles of copper oxides, though this is better done by the cartridge filters. Inductotherm Closed-Circuit Industrial Coolers, 2023 Inductotherm Corp. | ALL RIGHTS RESERVED, Horizontal Induction Tunnel Furnace Systems, Induction Systems for Vacuum and Controlled Atmospheres, High Resistance Load (HRL) Melting Systems, No Condensation Problems When Used with a Diversion Valve, Minimum Corrosion, Scaling and Electrolysis, Internal Water-to-Water Heat Exchanger for Ease of Installation, Completely Closed-Loop Pressurized Circuit, Fan Cycling Controls for Reduced Power Usage. -Deionized process cooling water, which can be either open or closed. Copyright 2012 - 2018 Walter Louis Fluid Technologies /, Cooling Water Corrosion and Scale Inhibitors, Its Just Water-How Can It Cause So Many Problems, Water Treatment is Key to Maintaining Boiler Efficiency, Cooling Tower: Total Dissolved Solids Control. Closed circuit cooling systemsimprove performance and efficiency by up to 50% savings compared to open systems. They're made for water-cooled, heat-producing processes and equipment that require coolant supply temperatures . If bacteria are allowed to propagate inside the closed-loop system, they can create a living deposit. This is the basis of mechanical deaeration. Cartridge filters that are normally supplied are 5m, and some plants have found that moving to a 1m cartridge filter is helpful. Pfannenberg, Inc., a leading global manufacturer of thermal management and signaling technologies, highlights its high-efficiency liquid cooling solutions for industrial electronics. Many processes today rely on chiller systems that are closed-loop. Other closed recirculating cooling applications include smelt spout cooling systems on Kraft recovery boilers and lubricating oil and sample coolers in power plants. 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. By visiting this website, certain cookies have already been set, which you may delete and block. However, in diesel and gas engines, the high temperature of the jacket water significantly increases its tendency to deposit scale. Visit our updated, This website requires certain cookies to work and uses other cookies to help you have the best experience. Our focus is on offering self-contained, air-cooled recirculating chillers from 1/2 ton to 20 ton capacities from a variety of industrial chiller manufacturers. A slightly alkaline pH increases the stability of either oxide layer. Lowering the pump speed can conserve energy when cooling needs decrease. block. Closed systems are also widely used in air conditioning chilled water systems to transfer the refrigerant cooling to air washers, in which the air is chilled. Closed systems are also less susceptible to biological fouling from slime and algae deposits than open 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. The cooling loop removes heat from the stator bars and conveys it away through heat exchangers. . The most common problem with these systems is black magnetic iron oxide mud deposits. The control of biological agents, like bacteria and algae, is vital to any effective cooling water treatment. Chromate treatments in the range of 500-1000 ppm as Cr4O2are satisfactory unless bimetallic influences exist. All of this is achieved with the help of power-driven fans, which classify this cooling system type as mechanical. For this reason, they are sometimes referred to as a closed loop circulating pump. With such pure water conditions, the pits created by any localized corrosion are very small. At up to 170F (77C), the curves are essentially parallel. Equipment and cooling system maintenance costs are reduced, and equipment reliability and productivity are increased. Grab sampling is not usually done due to the amount of water required to flush out sample lines before one can be sure of getting an accurate sample, which then needs to be replaced. is a priority both with our cooling water chemical treatment programs and the environment. Sodium nitrite has been in use for many years to prevent corrosion in a wide variety of closed-loop systems. Factors like new water piping, cooling cycles, and water recycling processes can offset the efficiency of cooling systems drastically. For mixed metallurgy systems, the molybdate inhibitors provide the best corrosion protection. The American Society of Refrigeration Engineers has established chromate limits in brine treatments. 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. Experts recommend a minimum of 1 ppm of dissolved oxygen in molybdate-treated systems. Get a quote. Industrial cooling towers and closed loop efficiency can be adversely affected by corrosion, scaling, fouling and biological contamination. From our low maintenance design Box 157 Rancocas, NJ 08073-0157. 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 target pH for the water is generally considered between 8.5 and 9.0 and may be obtained by adding small amounts of caustic to the water or by substituting sodium exchange resin for the hydrogen form cation resin in one of the deionizer vessels and metering the water through this exchanger until the pH reaches the desired level. Closed recirculating systems have many advantages. Explore five specific ways you can use less water in your facility below. After chemical treatment is added to a system a water analysis should be performed. Aside from emergency use, closed circuit cooling systems also serve to cool down components at a power plant. Molybdate treatments should not be used with brine-type antifreezes. 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. Process water loops often experience much higher temperatures and velocities as much as 10 feet per second. Due to increased iron level (up to 50 ppm), we plan to flush the systems and replace it with new glycol water. Therefore, this system requires special understanding, attention, and monitoring (Figure 2). One characteristic of these systems is that the system (that contains them) itself, needs to be quite massive. The system should then be flushed. Before doing the chemical treatment of any water piping system the flushing is must. For instance, backup power generators used for commercial structures like hospitals or industries typically have closed loop systems. 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. We stock many models of water chillers that are ready for quick delivery! This means that the decrease in temperature is rapid, reliable, and as effective as it gets. A closed loop water chiller system can be installed in any building, regardless of its size or age. Curve B shows data for a vented system. This separates the working fluid, which means that there is no water loss in this system, as a result. Regardless of which of the three chemical treatments you choose, they are likely to also contain pH buffers (caustic and sodium borate are common) to maintain an alkaline pH, which is conducive to minimizing corrosion in carbon steel. 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. Industries often need backup plans in the event of power losses. If you already have a closed loop system, youll feel you made a quality investment. Matt Welsh is the Vice President and Water Consultant at Chardon Labs. Efficiency also increases in the winter when closed loop systems can operate dry, preventing freezing during the colder months. Overheating of stator bars can result in reduced generating capacity or even catastrophic failure of the generator. Several sectors take advantage of more efficient closed circuit cooling systems. You may edit your selections at any time. These microbes can be introduced to the system in many ways. Diesel engines in stationary and locomotive service normally use radiator systems similar to the familiar automobile cooling system. Another advantage of getting a closed-loop cooler is that it can be significantly more efficient at maintaining low . Monitoring the health of stator water systems includes not only the chemical parameters like dissolved oxygen and conductivity. stand-alone cooling towers, closed-loop cooling with PHEs requires less make-up water and a minimum of water treatment. If sour gas leaks from the power cylinder into the water circuit, significant chromate reduction will occur, causing poor corrosion control and deposition of reduced chromate. Copyright 2023 Manufacturers of Cooling Towers & Systems by Delta Cooling Towers, Inc. All rights reserved. Should you need to replace your system, consider how a closed system can save you moneyprovided that you monitor and adequately treat the system over the years you use it. Series Pump Station is a packaged, open-loop water system featuring a dual-chambered, stainless steel t . The service requires full cookie support in order to view this website. Coolant . Closed Loop Chillers come complete with an Installation Kit and Glycol for Start up. Moreover, its what gives power plants their iconic look. Cooling water treatment services. Other closed-loop cooling systems can include chilled water systems for air chillers used at the air inlet to the gas turbines at a combined cycle power plant and the chemistry sample panel. Biocides make it possible to control such factors, with two classes of biocides available: It is crucial to control bacterial levels in closed water systems from the point of the first fill. One of the most common industry uses for cooling systems of this type can be found in power stations or natural gas plants. One drawback to nitrite treatments is the fact that nitrites are oxidized by microorganisms. The bacteria also generate biofilms, which create deposits producing areas that are anodes to the rest of the piping. Some of the concerns with closed loop systems are corrosion, scale, particulate and microbiological growth. In a typical dual-loop system, VIPPower Supply Unit cooling is achieved through a heat exchanger coupled to a furnace cooling tower loop. A closed-loop cooling system can exchange heat with the main cooling water system in conventional tube and shell heat exchangers or plate and frame heat exchangers. In nuclear facilities, redundant cooling mechanisms are critical to the safety of the plant. Over time, magnetic iron oxide particles bind together and collect on narrowed parts of the system. Thats why stator cooling water should be continuously monitored for conductivity and dissolved oxygen.