Methods for cleaning and descaling condensers
The condenser is prone to scale formation in the pipeline after long-term use. If not treated in a timely manner, these scales will affect the heat exchange effect, leading to an increase in the condensing temperature of the unit, which in turn leads to a decrease in cooling capacity and an increase in unit power consumption. Therefore, the condenser should be regularly cleaned of scale.
There are roughly three methods for preventing and removing scale:
1. Mechanical descaling method: Mechanical descaling is a method of descaling steel cooling pipe condensers using a soft shaft pipe washer, especially suitable for vertical shell and tube condensers.
The operation method is:
1. Extract the refrigerant from the condenser.
2. Close all valves connecting the condenser to the refrigeration system.
3. The cooling water supply to the condenser is normal.
4. The umbrella shaped gear shaped scraper connected with a flexible shaft pipe washer rotates and rolls to remove dirt from the vertical pipe of the condenser from top to bottom, and uses circulating cooling water to cool the heat generated by the friction between the scraper and the pipe wall. At the same time, the cleaned dirt such as scale and rust is washed into the water tank.
During the descaling process, the appropriate diameter of the roller is determined based on the thickness of the condenser's scale formation, the degree of corrosion on the pipe wall, and the length of service life. However, the diameter of the roller used for the first descaling is slightly smaller than the inner diameter of the cooling pipe to prevent damage to the pipe wall. Then, a roller close to the inner diameter of the cooling pipe is selected for the second descaling, which can remove more than 95% of the scale and rust in the condenser.
This mechanical descaling method utilizes the rotation and vibration of the bevel gear shaped roller during the rotation and feeding process inside the cooling tube to remove scale and rust from the condenser cooling tube. After the descaling is completed, all water in the condensate pool is pumped out, and the dirt and rust removed from the bottom of the pool are cleaned and refilled.
2. Chemical acid cleaning and descaling method: Clean the condenser with a prepared weak acidic descaling agent to remove scale and improve the heat transfer efficiency of the condenser.
The operation method is:
1. Prepare a descaling solution in the pickling tank, start the pickling pump, and circulate the descaling agent solution in the condenser condenser condenser for 24 hours. Generally, the scale is basically removed after 24 hours.
2. After stopping the acid cleaning pump, use a circular steel brush to pull and brush back and forth inside the pipe wall of the condenser, and rinse off the scale and rust with clean water.
3. Rinse the remaining detergent solution in the tube repeatedly with clean water until it is completely clean. The chemical acid cleaning and descaling method is suitable for both vertical and horizontal shell and tube condensers.
4. Electronic magnetic water descaling method: The working principle of an electronic magnetic water device is to dissolve calcium, magnesium, and other salts in the cooling water flowing through the condenser in a positive and negative ion state in water at room temperature.
When the cooling water flows through the transverse magnetic field of the magneto at a certain speed, the dissolved calcium and magnesium plasma obtains induced electrical energy, causing changes in its charge state. The electrostatic attraction between ions is disturbed and destroyed, which changes its crystallization conditions, making the crystal structure loose, reducing its tensile and compressive strength, and unable to form hard scale with strong adhesion. It becomes loose sludge and is discharged with the flow of the cooling water.
This descaling method can effectively prevent the generation of new scale and also remove existing scale, because after using an electronic magnetic water heater, ions lose the ability to scale, which loses the protective effect on the existing scale. In addition, the magnetized cooling water has a certain amount of induction power. At the same time, because the expansion coefficient of the steel pipe in the condenser is different from that of the scale, the original scale gradually cracks, and Magnetic water treatment continuously invades its cracks, destroying the adhesion of the original scale, making it gradually loose and fall off and constantly taken away by the circulating cooling water.
The descaling method of electronic magnetic water heaters is simple and easy to operate, with low labor intensity, and can be used to remove and prevent scaling without affecting the normal operation of the refrigeration system.
The significance of scale removal and energy conservation:
Once the condenser has scale, the thermal resistance of heat conduction will increase, so the thermal resistance will increase, and the value of heat transfer coefficient will decrease. Because the condensation temperature is inversely proportional to the Heat transfer coefficient, the temperature of the condenser will increase, and the condensation pressure will also increase accordingly. The more serious the scaling of the condenser is, the more significantly the condensation pressure will increase, which will increase the power consumption of the refrigerator and the power consumption of the operating equipment of the refrigeration system, Causing waste of electrical energy.