What are the applications of carbon steel spiral plate heat exchangers in the refrigeration industry
Information summary:Carbon steel spiral plate heat exchangers are mainly used in the refrigeration industry for heat exchange between media due to their compact structure, high heat transfer efficiency, and strong resistance to fouling and blockage. They are particularly suitable for low corrosion and high flow rate conditions. Its specific application scenarios are as follows:
Carbon steel spiral plate heat exchangers are mainly used in the refrigeration industry for heat exchange between media due to their compact structure, high heat transfer efficiency, and strong resistance to fouling and blockage. They are particularly suitable for low corrosion and high flow rate conditions. Its specific application scenarios are as follows:
1、 Condensation and evaporation in refrigeration systems
1. Condenser
In ammonia refrigeration, fluorine refrigeration and other systems, carbon steel spiral plate heat exchangers can be used as condensers to exchange heat between the high-temperature and high-pressure refrigerant vapor (such as ammonia vapor, R22/R134a vapor) discharged from the compressor and cooling water (or air), condensing the refrigerant into liquid state.
Advantages: The turbulence effect of the spiral channel is strong, which can enhance the heat transfer efficiency between the refrigerant and the cooling water. The carbon steel material has good compatibility with refrigerants such as ammonia and Freon (in non acidic environments), making it suitable for medium and low temperature refrigeration systems (condensation temperature is usually between 30~50 ℃).
2. Evaporator
In indirect refrigeration systems, it can serve as a heat exchanger between a refrigerant (such as saltwater or ethylene glycol solution) and a refrigerant. For example, low-temperature saltwater (-10~-20 ℃) flows in a spiral channel and exchanges heat with liquid refrigerant (such as ammonia) on the other side. The refrigerant absorbs heat and evaporates, achieving cooling of the refrigerant, and then supplying cold storage and cold chain equipment through the refrigerant.
Applicable scenarios: Indirect refrigeration systems for small and medium-sized cold storage and food freezing processing lines, utilizing the compact structure of spiral plates to save installation space.
2、 Heat exchange between refrigerant and cooling water
In the refrigeration system, the temperature of the refrigerant (such as salt water, ethylene glycol) increases after absorbing the cooling capacity. It needs to be cooled by exchanging heat with the cooling water (or circulating water in the cooling tower) through a heat exchanger before entering the refrigeration process again. The carbon steel spiral plate heat exchanger serves as an "intermediate heat exchanger" in this process, achieving heat transfer between the refrigerant and the cooling water
Advantages: The spiral channel is not easily blocked, suitable for working conditions where the cooling water contains a small amount of impurities (such as circulating water in open cooling towers), and a single device can handle large flow rates of refrigerant, meeting the heat exchange needs of small and medium-sized refrigeration systems.
3、 Oil cooling of refrigeration unit
When the refrigeration compressor is running, lubricating oil will circulate with the refrigerant. If the oil temperature is too high, it will affect the lubrication effect and compressor efficiency. Carbon steel spiral plate heat exchanger can be used as an oil cooler, using refrigerant or cooling water to cool high-temperature lubricating oil (usually with an oil temperature of 60-80 ℃), ensuring that the lubricating oil works at a suitable temperature.
Features: The high turbulence state of the spiral channel can quickly remove heat from the oil, and the carbon steel material is resistant to long-term erosion by lubricating oil, with low maintenance costs.
4、 Waste heat recovery and energy conservation
In the auxiliary section of the refrigeration system, carbon steel spiral plate heat exchangers can be used to recover waste heat. For example:
Recovering some of the heat from the compressor exhaust and heating hot water for cold storage (such as defrosting hot water and workshop cleaning water) to achieve secondary energy utilization;
Utilizing the condensation heat of the refrigeration system to preheat boiler feedwater and reduce boiler energy consumption is particularly suitable for scenarios that require both refrigeration and hot water, such as food processing plants and hotel cold storage.
5、 Suitable for special scenarios with low corrosion conditions
Due to the weak corrosion resistance of carbon steel material (easily corroded by acidic media and high salt solutions), its application needs to avoid strong corrosive environments, but it performs stably in the following low corrosion refrigeration scenarios:
Ammonia refrigeration system (ammonia is alkaline, carbon steel has good corrosion resistance in dry ammonia environment, but it is necessary to avoid corrosion caused by high moisture content in ammonia solution);
Freon refrigeration system (non-polar refrigerant, non corrosive to carbon steel, suitable for use with cooling water and refrigerant (such as ethylene glycol)).
Application restrictions and precautions
Carbon steel material is not resistant to long-term corrosion in strong acid, high salt or humid environments, so it is not suitable for heat exchange scenarios with seawater cooling and acidic refrigerants (such as when the concentration of calcium chloride solution is too high). Otherwise, anti-corrosion treatment (such as painting and lining) is required;
The channel of the spiral plate heat exchanger is relatively narrow (usually 2-10mm). If the medium contains a large amount of impurities or is prone to crystallization (such as high concentration saltwater crystallization at low temperatures), it may cause blockage and requires regular cleaning and maintenance.