The quality and length of operation of the heat exchanger are closely related to whether daily maintenance, cleaning and maintenance are timely and appropriate. When the heat exchanger is in use, dirt deposits will inevitably appear on the heat transfer surface, causing scaling. The thermal resistance of the dirt deposits is high, which greatly reduces the heat transfer rate; at the same time, the flow channel is reduced due to scaling. area, medium flow resistance increases, and energy consumption increases. For fluids that are prone to scaling, appropriate methods can be used to descale them at the specified time. Hebei Baixiang Chemical Machinery will introduce to you the factors that affect the scaling of heat exchanger equipment.
There are many factors that affect heat exchanger fouling, such as fluid speed, fluid flow state, composition and content of fluid components, and the structure of the heat exchanger, which all have a certain impact on the formation of fouling. Only by identifying the main factors can we Effectively solve the scaling problem.
1. Temperature of the heat transfer wall: Temperature plays an important role in chemical reaction scaling and salt crystallization scaling. An increase in fluid temperature generally leads to an increase in the chemical reaction speed and crystallization speed, thereby affecting the amount of dirt deposited. influence, resulting in increased fouling growth rate.
2. Fluid flow rate: In the heat exchanger, the effect of flow rate on dirt should be considered at the same time as its effect on dirt deposition and dirt erosion. For various types of dirt, the increase in the erosion rate caused by the increase in flow rate is greater than the increase in dirt deposition. The rate is more significant, so the fouling growth rate decreases with increasing flow rate. However, in the actual operation of the heat exchanger, the increase in flow rate will increase the energy consumption. Therefore, the higher the flow rate, the better. Energy consumption and dirt should be considered comprehensively.
3. Hot surface material and surface quality: For commonly used carbon steel and stainless steel, the deposition of corrosion products will affect scaling; however, if non-metallic materials such as graphite or ceramics with good corrosion resistance are used, scaling is less likely to occur. The surface quality of the heat exchange surface material will affect the formation and deposition of dirt. The greater the surface roughness, the more conducive to the formation and precipitation of dirt.
September 27, 2023
