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Vacuum Pump for Vacuum Cooling: Essential Guide

September 8, 2023

Vacuum cooling:

Vacuum cooling is mainly used for cold treatment of food, fruits and vegetables, and cut flowers. This cooling technology not only largely improves the product quality, but also increases the shelf life of the product and, at the same time, it reduces the cooling costs compared to the conventional cooling methods available. Vacuum cooling is to vacuum the fruits and vegetables in the vacuum chamber into the insulated vacuum chamber. When the corresponding water vapor, fruits and vegetables with water saturation pressure on the gap surface of fruits and plant fibers start to evaporate in vacuum at room temperature, the evaporation will evaporate the far end latent heat, which will reduce the temperature of fruits and vegetables, and further reduce the temperature of vegetables to the required temperature. Water boils at 100 ℃ at atmospheric pressure. However, the pressure drop and boiling point are also reduced, which can reduce the boiling point of water available for this phenomenon, but in order to evaporate water, heat must be absorbed. Under vacuum, the moisture on the surface and inside of crops begins to evaporate and is pumped out together with the air by the vacuum pump.

Vacuum cooling principle:

The principle of vacuum cooling is similar to vacuum drying, in which water evaporates rapidly under vacuum. The difference is that vacuum drying is to remove water, and vacuum cooling is only to remove heat by evaporating water to achieve cooling and cooling. The professional vacuum pump supplier tells you some knowledge that water evaporates at 100 ° C under normal pressure, and the evaporation heat is 2256kj / kg. When the pressure drops to 610pa, the water will boil at 0 ° C (at this time, it is also the three-phase point of water, and the evaporation heat is 2500kj / kg. In other words, in the state of low-pressure vacuum, the evaporation of water will take away more heat, so as to achieve the refrigeration effect.

In daily life, water boils at 100 ° C at a atmospheric pressure (101-325 PA). However, the boiling temperature of water is not constant and decreases (or increases) as the pressure decreases (or increases). For example, the boiling point of water is 76 ℃, the temperature is 40 196.6 PA, 29 ℃, 4 kPa, 14 ℃, 1.6 kPa. Lower the boiling point to make the water evaporate easily. Because steam water molecules have higher energy than liquid water molecules, water must absorb the latent heat of evaporation when evaporation, and its latent heat of evaporation increases with the decrease of boiling point. According to the principle, the object to be treated can be placed in a closed vacuum box, which can bear a certain negative pressure and be pumped by a suitable vacuum system. With the increase of vacuum degree in the vacuum tank, the boiling temperature of water decreases. It is easy to evaporate, when water evaporates, it can only absorb the heat of the object itself, and can quickly cool the object to be processed.

The core equipment of vacuum cooling is the vacuum chamber and the imported vacuum pump. After the product enters the vacuum chamber, the main process begins to pump air, reducing the pressure in the chamber. This reduction in pressure allows the water in the product to start evaporating, resulting in rapid cooling. The use of vacuum cooling improves product quality and increases the shelf life. In some cases, condensation equipment may be required to capture water vapor.

Compared with air cooling, water cooling and other cooling methods, vacuum cooling has the advantages of energy saving, fast cooling speed, relatively uniform cooling and little impact on product structure. It also has the problems of large investment and high weight loss rate. But on the whole, it is also a fast and safe cooling technology, which transcends the shortcomings and can obtain high-quality products.

The vacuum cooling process offers several key advantages, making it a highly efficient and effective method of refrigeration. One of the main benefits is its low energy consumption, which helps reduce overall operational costs. Additionally, vacuum cooling enables fast refrigeration time, significantly reducing the time it takes to cool large quantities of produce. This is particularly beneficial for perishable items like leafy vegetables, which can quickly lose their freshness and spoil after harvesting. By taking advantage of the low boiling point of water under vacuum, the vacuum cooling process can rapidly cool these vegetables, extending their shelf life and preserving their quality.

Under vacuum, the moisture on the surface and inside of crops undergoes a process of evaporation and is subsequently removed along with the air by the powerful vacuum pump. This innovative technique has proven to be particularly effective in preserving the freshness and extending the shelf life of various food products, including bread and sushi rice. A key player in this field is the Vacculecx screw vacuum pump, renowned for its exceptional pumping speed and remarkable tolerance to water vapor. With its advanced capabilities, this vacuum pump plays a vital role in ensuring the quality and longevity of food products, ultimately revolutionizing the way we preserve and enjoy our favorite culinary delights.

What Is a Vacuum Pump for Vacuum Cooling and How Does It Work?

A vacuum pump is an essential component of the vacuum cooling process. Vacuum cooling is a method used to rapidly cool products, such as food or electronics, by removing air and creating a low-pressure environment. The vacuum pump is responsible for creating and maintaining the vacuum inside the cooling chamber.

The vacuum pump works by removing air molecules from the chamber, which lowers the air pressure. This reduction in pressure causes water to evaporate at a lower temperature, allowing for rapid cooling of the product. The vacuum pump creates a continuous flow of air out of the chamber, maintaining the low-pressure environment necessary for effective cooling.

There are different types of vacuum pumps used in vacuum cooling systems, including screw vacuum pumps. Using a vacuum pump in conjunction with other components of a vacuum cooling system allows products to be cooled quickly and efficiently while preserving their quality.