A, jacketed heat exchanger

Jacketed heat exchanger has a simple structure and is made by installing a jacket on the outer wall of the container.

Advantages include:

1. High heat transfer efficiency: the fluid in the jacket can effectively transfer heat to the substance in the container.

2. Temperature control: The temperature of the fluid in the jacket can be accurately controlled, so as to realize the heating or cooling of the material in the container.

Disadvantages include:

1. Limited heat transfer area: The heat transfer area of the jacket is limited by the size of the container.

2. Thermal stress: Due to the different coefficient of thermal expansion of the container and jacket material, thermal stress may be generated.

3. Pressure limitation: The jacket design may not be able to withstand excessive pressure, limiting its use in high-pressure environments.

Figure 1-1 Schematic diagram of product structure

Second, immersed coil heat exchanger:

The snake tube is mostly bent and wound by a metal tube, and the two fluids are immersed in the container and flow inside and outside the tube respectively.

Advantages include:

1. Strong adaptability: suitable for a variety of fluids and process conditions, including corrosive or viscous media.

2. Good pressure resistance: the snake tube is usually able to withstand high pressure.

Disadvantages include:

1. Low heat transfer efficiency: Compared with other types of heat exchangers, the heat transfer coefficient of coil heat exchangers is usually lower, because the flow of fluid outside the tube may not be sufficient.

2. Thermal expansion problem: the snake tube may cause stress due to thermal expansion during heat exchange, requiring appropriate design to avoid damage.

3. Fluid flow rate limit: In order to ensure heat transfer efficiency, the flow rate of the fluid in the snake tube can not be too high.

Figure 1-2 Schematic diagram of product structure

Three. Tube heat exchanger

Tube heat exchangers are concentric tubes made of straight tubes of different diameters and connected by U-shaped elbows. One fluid goes through the tube and the other fluid goes through the annular gap.

Advantages include:

1. High heat transfer efficiency: the two fluids can flow in the case of pure countercurrent or parallel flow, which can not only improve the logarithmic average temperature difference, but also improve the heat transfer efficiency.

2. High reliability: Because the fluid flows in the tube, the possibility of the fluid directly impacting the heat exchange surface is reduced, thus improving the reliability of the equipment.

Disadvantages include:

1. High pressure drop: Because the fluid flows in the annular gap, there may be a high pressure drop, especially when the flow rate is high.

2. Thermal expansion problem: Due to the different coefficient of thermal expansion of the inner and outer tubes, long-term operation may lead to stress concentration or leakage.

Figure 1-3 Schematic diagram of product structure

Four. Shell and tube heat exchanger

Shell and tube heat exchanger (tubular heat exchanger) is one of the most typical wall heat exchangers, widely used in industrial fields.

Advantages include:

1. Efficient heat transfer: high heat transfer coefficient, suitable for heat exchange of various media.

2. Widely used: It is suitable for the heat exchange of liquid-liquid, liquid-steam and other media.

3. High reliability: Because of its simple structure, easy maintenance, high reliability.

Disadvantages include:

1. Large heat loss: Due to the large heat exchange area, if the insulation measures are improper, there may be a large heat loss.

2. There may be dead corners: In some designs, shell and tube heat exchangers may have dead corners for fluid flow, resulting in reduced heat transfer efficiency.

Figure 1-4 Schematic diagram of product structure

Five. Plate heat exchanger

Plate heat exchangers consist of a series of corrugated metal sheets stacked to form thin rectangular channels for heat exchange.

Advantages include:

1. High heat transfer efficiency: the corrugated shape of the plate can destroy the boundary layer of the fluid, improve the degree of turbulence, and thus improve the heat transfer coefficient.

2. Lightweight: Due to the use of thin metal plates, the weight of the entire heat exchanger is relatively light.

Disadvantages include:  

1. Pressure resistance: Although the plate heat exchanger can withstand high pressure, too high pressure may damage the plate or gasket.

2. Blockage problem: the channel between the plates is narrow, easy to be blocked by solid particles, and a good     Pre-treatment or regular cleaning.

3. Corrosion problem: If the medium is corrosive, the plate may be corroded, requiring the use of corrosion-resistant materials or special surface treatment.

Figure 1-5 Schematic diagram of product structure

Six. Regenerative heat exchanger

A regenerative heat exchanger is a heat exchange device that uses a regenerative body (usually a solid filler) to store and release heat.

Advantages include:

1. High temperature operation capacity: regenerative heat exchangers can operate under extreme high temperature conditions, suitable for more than 1300℃ environment.

2. High thermal efficiency: Through the process of heat storage and heat release, high heat recovery efficiency can be achieved.

3. Energy saving: By recycling waste heat, it helps to reduce energy consumption and operating costs.

Disadvantages include:

1. Heat transfer speed: Compared with the direct contact heat exchanger, the heat transfer speed of the regenerative heat exchanger may be slower.

2. Heat loss: There may be some heat loss in the process of heat storage and heat release.

3. Fluid limitation: Regenerative heat exchangers are generally not suitable for fluids that are easily vaporized or mixed.                

Figure 1-6 Schematic diagram of product structure