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In the previous article, the issue of what is an industrial refrigeration and what is its application in industry. In this article, we will classify the types of industrial refrigerators based on the different characteristics of different types of industrial refrigerators.
Types of industrial refrigeration in terms of temperature range
In general, two types of temperature range are installed for refrigerators: above zero and below zero.
Refrigerator above zero
Some materials lose their physical and chemical properties at sub-zero temperatures, so the required temperature is taken into account for their storage, and these contents will be stored in industrial refrigerators above zero. The temperature range of industrial refrigerators above zero is usually between one and 15 degrees Celsius. These refrigerators are usually used to store products that are supposed to stay in the refrigerator for a shorter period of time. Especially when it comes to food storage, many of them do not reach the freezing point, so they are stored in refrigerators above zero. Of course, refrigerators with specific purposes are also built and used to cool contents for a long time.
Refrigerator below zero
Sub-zero industrial refrigerators are used to freeze the contents inside. The temperature range of these refrigerators is defined between minus five to minus forty-five degrees Celsius, but its usual average is a more limited range. Sub-zero refrigeration will be used for long-term storage and has a higher cooling capacity. The main cause of this high cooling capacity is the compressor device inside. Sub-zero refrigeration compressors do the compression work in several stages, so the heat of this heating process is not so high. The compressor motor of this refrigerator has less power and although the fluid in it circulates faster, but the compressor has less power. On the other hand, if the amount of heat generated by the refrigeration compressor above zero is not controlled, the heat generated will have a negative effect on cooling.
Two-circuit refrigerator
When an industrial cold store above zero and below zero is required at the same time, a dual-stage industrial cold store is used, which is a combination. This type of refrigerator is used to store different materials and contents. In this way, the refrigerator is emptied once of the contents and again filled with the contents that need another specific temperature. For this reason, before refilling this two-circuit refrigerator, all its compartments and walls must be cleaned and disinfected of previous materials. This is because the temperature that is now to be chosen for the second time may cause the previous materials to rot and decay. This is to the detriment of the materials of the second stage, and it causes physical damage to the internal building of the cold storage, and its health is questioned. The least hygienic thing is that the smell of the first stage products stays in the refrigerator and causes an unpleasant odor and affects the second stage products.
Types of industrial refrigeration in terms of division of dimensions
Since industrial refrigerators are large refrigerators for storing bulk materials, their internal buildings will be divided into several separate sections. This means that if, for example, the capacity of a cold storage is 2000 tons, it will be divided into 8 250-ton halls or two 1000-ton halls.
Types of industrial refrigeration based on gas consumption
In general, there are two types of gas consumption categories for refrigerators, which are defined in the form of freon and ammonia. Each of these two gases has its own characteristics, advantages and disadvantages and can be used for refrigerators with different capacities. But basically because ammonia is productive for refrigerators with high refrigeration capacity, large industrial refrigerators use ammonia gas for their refrigeration cycle. In fact, the fact is that ammonia gas is only suitable for high-capacity refrigerators and is not efficient for low-capacity refrigerators. Ammonia has the highest refrigeration effect between refrigerants available for refrigeration and has a low operating cost for large refrigerators such as industrial refrigerators.
Types of industrial refrigeration based on building and refrigeration speed
A conventional refrigerator cannot cope with the high speed of refrigeration when it is necessary to cool or freeze the contents suddenly. To do this, you need to use a freezing tunnel, which is a kind of industrial cold storage. How the freezing tunnel works (which is in the group of fast freezing methods) is that the cold air flow is in direct and indirect contact with the contents and by passing this cold air flow, air movement occurs. This compulsion in moving the air to achieve temperature equilibrium results in a very significant temperature drop for the contents inside the tunnel. The important point in the industrial refrigeration of the freezing tunnel type is its operating speed. The amount of coarseness and fineness of ice crystals in the contents depends on the rate of freezing and the incorrect size of the crystals damages the physical and chemical properties of the contents. As the solidification rate increases, the crystals become smaller and the texture and physical properties will be preserved as they are. This is even more important for frozen foods.
But it should be noted that the industrial cold storage of the freezing tunnel itself has different types. Freezing tunnels, in terms of performance to types
A blower, which directs cold air to the contents of the refrigerator with the help of fans, thus contacting them with cold air.
Contact, that the material itself is placed between the walls taken or passed through the conveyor belt through the freezer or tunnel path
Conveyor operation, as mentioned above, is more suitable for industrial production lines
Operation with liquid nitrogen, which differs from all three methods of rapid mechanical freezing mentioned above, works in such a way that the contents to be frozen are immersed in liquid nitrogen at a very low temperature or in other words drown. To reduce the temperature and reach the freezing stage
Tunnel with linear freezing path or with spiral freezing path
And other items are divided.
