One of the biggest expenses in any factory or manufacturing capacity is the expense of a chiller. Keeping things cool is expensive and requires a high level of energy. New innovations are made every year in the technology and energy-efficiency of chilling equipment on the consumer and industrial level.
But did you know how much more cost-effective new chillers are than old chillers? One company in San Francisco was able to save over $1.3 million dollars each year once they switched to a new chilling system. This company switched out old absorption chillers for new energy-efficient electric chillers. The company also upgraded the chilled water distribution system. The addition of the new system also saved over $100,000 in maintenance costs each year and the company was able to recover the cost of the system in fewer than 6 years.
Generally, when a company upgrades their chilling system, it is down out of necessity and the goal is to save as much during installation as possible. However, a shortsighted view like that can actually cost a company big money in the long run. By considering the long-term, this company was able to take funds traditionally spent on their utilities and use them for upgrades in other aspects of the business to increase profits. One simple move of upgrading the chiller system enabled the company to benefit as a whole on multiple levels.
The idea of spending money now to save money later is not a new idea, but few companies actually implement this idea. However, as the San Francisco company shows, upgrading one system can actually have a positive impact on the company as a whole and increase profits permanently.
Chillers can be used either for air conditioning or for material and process cooling. Process chillers cool products and machinery in processes such as plastic injection molding, blow molding, metalworking, welding, die casting, chemical and pharmaceutical processing, food and beverage processing, lab equipment, photographic processing, medical imaging machines, gas cooling and lasers. In plastic forming, for example, chillers reduce cycle times in injection molding by quickening the cooling process. Chocolate manufacturers often use chillers to regulate the chocolate's temperature during processing to keep it from burning. Printing presses require chiller systems for rolling and pressing to reduce bleeding and stretching of photographs. Some specific types of industrial chillers and medical chillers include water chillers, recirculating chillers, absorption chillers, air cooled chillers, water cooled chillers, centrifugal chillers and screw chillers.
Chillers are machines that remove heat from liquids and release it into the atmosphere by means of a refrigeration cycle. The chilled liquid, also known as a coolant, is then directed to a heat exchanger to cool process equipment, air or another liquid. Chiller systems range vastly in size and design and may be fabricated as small, localized or portable chiller units for small applications or as large central chillers designed to provide cooling for entire facilities.
A chiller manufacturer will use either absorption or vapor-compression refrigeration cycles to produce their cooling effect. Both cycles use a refrigerant that strategically absorbs heat in one place as it evaporates and then releases heat in another place as it condenses. In most chillers this occurs in a four-stage cycle of pressurization, condensation, depressurization, and evaporation. First, the refrigerant vapor is pressurized, either by heating or by means of a compressor. Second, the refrigerant moves into a condenser comprised of a coil or set of tubes with either water or air circulating around it. The refrigerant vapor cools inside the condenser and changes into a liquid, rejecting a large amount of heat in the process. This heat is absorbed and borne away by the water or air flowing around it. Thirdly, the refrigerant liquid proceeds through an expansion valve that decreases the pressure and allows for evaporation to take place. The flash evaporation that occurs at the expansion valve cools the liquid drastically. Lastly, the cold fluid moves into the heat exchanger or evaporator, where the remaining liquid refrigerant evaporates as it absorbs heat from the process (direct cooling) or process coolant (indirect cooling). In recirculating chillers, the refrigerant vapor is then drawn into the first compression stage to start the cycle over again.
Chillers come in a variety of types. Absorption chillers use a heat source to drive the refrigeration cycle, while vapor-compression chillers use a compressor to drive the cycle. The advantage of the absorption model is that it requires much less electricity, and can be powered by heat sources that might otherwise be wasted, such as heat-producing machinery or solar rays. On the other hand, vapor-compression is a readily-accessible and time-tested technology with more versatility and easier installation. There are a number of different types of vapor-compression chillers according to the type of gas compressor they use, the most common being centrifugal compressors, screw compressors and scroll compressors. Portable chillers usually use scroll compressors because they are the most compact and quiet. Another distinction between chillers has to do with the condenser. Condensers can be air cooled, water cooled or evaporation cooled. Air cooled chillers facilitate condensation of the refrigerant by blowing ambient air over the condenser coil or tubes and exhausting the hot air into the atmosphere, or in some cases using it to help heat the facility during the winter. Evaporation cooled chillers operate in the same way as air cooled chillers, except they introduce a mist of water in the air, the evaporation of which makes the heat transfer more efficient. Water cooled chillers employ a flow of water to take heat from the refrigerant in the condenser. This is the most effective condensing method, but also requires a constant source of cool water, and in most cases also necessitates an outdoor cooling tower and a pump to get the heated water there.
When installing a chiller system, there are a number of important considerations. Foremost is cooling capacity. Industrial chillers are measured by their cooling capacity in terms of tons, each ton being roughly equivalent to the heat of fusion of one ton of ice, or 12,000 Btu/h. Capacities range from portable chillers with fractions of a ton to permanent multi-unit "plants" with cooling capacities of thousands of tons. Another significant decision is the sort of refrigerant; this will mostly depend on the range of temperatures the chiller will face. Common refrigerant choices include water, ammonia, carbon dioxide, sulfur dioxide, alcohol, brine and methane. Fluorocarbons, especially chlorofluorocarbons (CFCs) have also been used widely as refrigerants, but they are decreasingly common because of their ozone depletion effects. Other specifications to look at include condenser and evaporator flow rates, power source, cooling capacity, efficiency, location, compressor type and compressor horsepower. Most chillers also come with a local and/or remote control panel with temperature and pressure indicators and emergency alarms. When configured properly, chillers can provide simple and effective solutions for many process cooling and industrial air conditioning applications.
Chillers - General Air Products, Inc.
Chillers - Cold Shot Chillers
Chillers - Advantage Engineering, Inc.
Chillers - Thermal Care, Inc.
Chillers - Thermal Care, Inc.
Chillers - Dimplex Thermal Solutions
Chiller Terms- The surrounding environment, including temperature, pressure and/or humidity, coming into contact with a system or component.
- A device that removes heat via forced air, water coil, etc., in order to convert a high pressure gas into a lower pressure liquid. Condensers remove heat from the compressed vaporized refrigerant, at which point, the refrigerant returns to a liquid state.
central part of a refrigeration system in which the system is operated
- A liquid used to remove heat.
- Indicates the efficiency of an air conditioner or cooling system by comparing the amount of energy needed to produce cooling with the quality of the system's cooling ability and is calculated by dividing the system's BTU by its wattage. For example, if a cooling system maintains 20,000 BTUs and uses 1,500 watts, the system's energy efficient rating would equal 13.3.
- Consists of a tube inside which the refrigerant soaks up heat from it surroundings, boils and changes to a vapor.
- Mechanism located between the evaporator and condenser that controls the refrigerant flow into the evaporator and controls the temperature of the evaporator.
- Removes moisture and contaminants from vaporized refrigerants.
- A device that transfers heat from one fluid to another without mixing the fluids. (Heat Exchangers)
- A substance containing chlorine, fluorine, carbon and hydrogen that is used as an alternative to CFCs as a refrigerant and a propellant. HCFCs produce fewer effects on than ozone layer than CFCs do.
- A substance containing hydrogen, fluorine and carbon that is used to replace CFCs and HCFCs because of HFCs lack of effect on the ozone layer. HFCs produce no ozone depletion because the substance does not contain chlorine, which breaks down the ozone layer.
- A process that utilizes light to cool atoms to a very low temperature.
- A molecule containing three oxygen atoms that absorbs ultraviolet radiation in the stratosphere. Ozone also remains a harmful component of smog and can contribute to lung damage and respiratory problems.
- A relative measurement of a substance's negative effect on the ozone layer as compared to the effects of CFC-11, which has an ODP of 1, on the ozone. For instance, a substance with an ODP of 2 can potentially cause approximately twice the ozone depletion as CFC-11 could.
- Also referred to as the stratospheric ozone, it is the protective atmospheric layer in the stratosphere, located 12-30 miles (20-50 kilometers) above sea level, in which ultraviolet radiation is absorbed.
- The storage area for condensed liquid refrigerants.
- Liquids that produce cooling upon evaporation.
- Unit equal to 12,000 BTUs that refers to the size of the chiller unit.
- A window in a refrigeration system through which specialists can view the inner workings of the system.
- Mechanism in a refrigeration system that controls the flow of refrigerant, especially into the expansion valve.
- The total amount of carbon dioxide that a refrigeration system can produce throughout its lifetime.