Although COVID-19 has caused a great deal of disruption in many industries, the global industrial refrigeration sector is considered essential, continues to grow, and plays a vital role in a wide variety of the food and beverage industry. For proper functioning, industrial refrigeration systems rely on different components and types of refrigerants to create cool conditions.
What Is Industrial Refrigeration?
Industrial refrigeration is the process of removing heat from an enclosed space, or from a substance, and moving it to a place where it is unobjectionable. The primary purpose of refrigeration is to lower the temperature of the enclosed space or substance and then maintain the lower temperature.
Refrigerants for Industrial Refrigeration
A refrigerant is a substance used in the refrigeration heat transfer cycle for moving heat from one region to another. It must be capable of reversible phase change from liquid to vapor and then from vapor to liquid under a range of reasonable temperatures and pressures. Up until 1987, the most used refrigerants were ammonia, halocarbons R12, R502, and R22. In 1987, The Montreal Protocol put halocarbons on the hit list, and replacement freons become popular in the commercial and industrial refrigeration industry.
R-134a HFC Refrigerant
This refrigerant is known as the replacement for R-12 and is used in various heat pump applications and other commercial refrigeration needs. In the future, it is predicted to be phased out across the world.
R-404a HFC Refrigerant Blend
This refrigerant is known as the replacement for halocarbons R12, R502 and R22, and is used in various commercial refrigeration needs. R404a is extremely high in global warming potential and is not the most efficient refrigerant. Due to this, it will also be eventually phased out of use.
R-744 Carbon Dioxide
This refrigerant is known as the replacement for halocarbons R12, R502, and R22 and is used in various commercial grocery stores and ice rinks’ refrigeration needs. R-744 is a natural refrigerant, but unlike other natural refrigerants, there is not a safety concern. With hydrocarbons, you have the flammability risk, with ammonia you have the toxicity risk, but with CO2 the safety risk is minimal. To be used as a refrigerant, carbon dioxide must run under extremely high pressure, which includes the pipes, components, and everything else that goes along with the machine. If lesser components are used, then you pose the risk of constant failure due to the high pressures.
Ammonia is one of the top picks when it comes to industrial refrigeration such as meatpacking Dairies, large cold storage warehouses, and breweries’ plants. Ammonia is 18% more efficient than freons. Ammonia is chosen as it is highly regarded as the most energy-efficient refrigerant out there. The downside is that ammonia is toxic and can also be slightly flammable. Because of that, OSHA, PMS, RMP, EPA documents need to be developed and monitored.
Components of Industrial Ammonia Refrigeration Systems
Industrial ammonia refrigeration systems are broken down into single stage and two stage, with different ways to feed the liquid to the evaporators. Namely, flooded, direct expansion, subcooled direct expansion, CPR feed, and pumped liquid recirculated.
- It is the prime mover of the refrigerant through an ammonia refrigeration system.
- Collects ammonia vapors generated in the evaporator and maintains its suction pressure.
- The compressor can increase the ammonia pressure and temperature, by reducing its vapor volume through compression.
- The compressor transfers the ammonia suction vapor developed in the evaporator to the condenser.
The ammonia compressor is a part of the refrigeration system where there is a separation between the high side and the low side. It is designed to accept vapor only. If ammonia liquid enters the compressor, there exists a high probability of severe damage to the compressor known as liquid slugging. The compressor uses more energy than any other component in an industrial ammonia refrigeration system.
Depending on the type of industrial refrigeration system in use, there are an array of industrial compressor options. These include:
- Reciprocating Compressor
- Screw Compressor
- The purpose of an ammonia condenser is to reject energy (heat) that the refrigerant absorbed into the system at the evaporator and compressor.
- The ammonia condenser is the place where the refrigerant superheated ammonia vapor changes state back to a liquid when heat energy is transferred out of the ammonia refrigerant.
Depending on the type of industrial refrigeration system in use, there are an array of industrial condenser options. These include:
- Air cooled adiabatic condenser
- Water cooled plate and frame or shell & tube condenser
- Evaporative condenser
- The purpose of an ammonia evaporator is to absorb heat from the area or product to be cooled.
- The Ammonia liquid vaporizes when heat is transferring into the refrigerant.
Depending on the type of industrial refrigeration system in use, there are an array of industrial evaporator options. These include:
- Forced air draw thru evaporators
- Plate and frame or shell & tube evaporators
- Process air handlers evaporators
- Jacketed process tanks and silos evaporators
Depending on the type of industrial refrigeration system in use, there is an array of industrial ammonia components that make the system complete. These include:
- Isolation and control valves
- ASME pressure vessels
- Ammonia pumps
- ASME pressure piping system
- Ammonia system safety controls
- Operating control system
Industrial Refrigeration Solutions From Kuhlman Inc.
Since 1957, Kuhlman Inc. has been dedicated to providing our customers with the highest quality industrial refrigeration solutions. We work closely with each client throughout every step of the process, from engineering and design to installation and continued service of the completed refrigeration system. To learn more about our industrial refrigeration solutions, contact us today.