Gansu Lanzhou heating station cleaning, heat exchange plate cleaning, heat exchanger cleaning, boiler cleaning
Several effective methods for plate heat exchanger cleaning
1. Backwashing method:
As the heat transfer capacity of the plate heat exchanger suddenly drops and the pressure drop increases, we generally judge that the plate heat exchanger may be blocked. In some working conditions that contain solid impurities, when the removal of external factors and the cleaning of imported cold and hot filters cannot be solved, the plate heat exchanger can be backwashed. Of course, we recommend that the heat exchanger of this working condition be put into use Before, it is necessary to equip a backwashing pipeline to backwash 2-5 times with a refrigerant or heat medium higher than the operating pressure from the opposite direction of the plate. At the same time, we recommend equipment with backwashing pipelines to set up a special drain outlet. , The blockage of backwashing can be excluded from the system. Because backwashing requires early investment and its effect cannot be eradicated, it is less used for inspection and maintenance.
2. Chemical cleaning method:
For stainless steel plate heat exchangers, it is forbidden to use acid cleaning agents and cleaning powders for chemical descaling, especially for the cleaning of the entire equipment without disassembly. This is because it is difficult to remove inadequately dissolved scale residues in multi-slit fouling, and alkali neutralization cannot be performed sufficiently. However, for plate heat exchangers with large plate sizes, a relatively large number of plates, and plate heat exchanger projects that are inconvenient to install, it is more recommended to use CIP online cleaning. Because acid and corrosive cleaning agents can be injected into the inside of the plate heat exchanger, the plates can be fully infiltrated, and the cleaning efficiency can be improved if properly heated. Since the cleaning agent is only inside the plate heat exchanger, it will not affect the environment while the amount is small. However, the difficulty of CIP online cleaning is that the dirt inside the plate heat exchanger must be analyzed before cleaning, and Use a cleaning agent to match it. If you don’t perform a test match, the cleaning agent that can be too high will easily corrode the heat exchanger plates and cause unnecessary losses.
Three, disassembly and cleaning method:
Disassembling and cleaning Master plate heat exchangers are more commonly used cleaning methods. Generally divided into two methods: 1. After removing the Zhengtai plate heat exchanger, it is not advisable to remove the plates. First hang on the upper beam of the heat exchanger, and then use clean water to pressurize them one by one, which is suitable for the plates where the fouling is not serious. Working conditions. 2. After opening the plate heat exchanger, remove the plates of the plate heat exchanger, remove the gaskets, and then beat the plates with a mallet. Generally, the dirt can be knocked down. If in winter, the plates can be knocked down. Move the sheet to the outdoors for a period of time. After the dirt on the sheet freezes, it will be better to remove the dirt by tapping. Do not use a brush or wire brush to clean. Place the sheet to damage the surface of the steel sheet, causing residue and corrosion to easily scale. . The plates are usually cleaned with thick brushes and chemical methods. It cannot be removed with a sharp knife to avoid scratching the plate. When the debris or dirt on the plate is very thin and soluble in water, the plate can be placed in a special water tank and rinsed with a certain pressure water or low pressure steam. Stainless steel plates must not use wire brushes. The cleaning water must not contain salt, sulfur and other ingredients. The content of chloride ions in the water is less than 20ppm.