Plate heat exchanger cleaning steps and precautions_
961 Due to the corrosion of the medium in the use environment, the plate heat exchanger has tube sheet leakage and tube sheet thinning after one year of use, which seriously affects the heat exchange efficiency and the normal production of the enterprise. At that time, the plate heat exchanger cleaning work will be carried out. Today, we will talk about the cleaning steps and related precautions of the plate heat exchanger. 1. Isolate the equipment system and drain the water in the heat exchanger cleanly. 2. Use high-pressure water to clean the silt, algae and other impurities in the pipeline, and then close the system. 3. Install a ball valve (not less than 1 inch u003d 2.54 cm) between the isolation valve and the exchanger, and both the water inlet and the water return port should be installed. 4. Connect the delivery pump and the connecting pipe so that the cleaning agent is pumped in from the bottom of the heat exchanger and out from the top. 5. Start pumping the required cleaning agent into the heat exchanger (the ratio can be adjusted according to the specific situation). 6. Repeat the cycle cleaning to the recommended cleaning time. As the circulation progresses and the deposits dissolve, the gas generated during the reaction will increase, and the excess air should be discharged through the purge valve at any time. As the air is discharged, the space in the heat exchanger will increase. Appropriate water can be added. Do not inject a large amount of water at the beginning, which may cause water overflow. 7. Check the effectiveness of the cleaning agent regularly during the cycle, which can be measured with a pH test paper. If the solution is maintained at a pH value of 2-3, the cleaning agent is still effective. If the pH value of the cleaning agent reaches 5-6, you need to add an appropriate amount of cleaning agent. The pH value of the solution remained unchanged for 30 minutes at 2-3, which proved that the cleaning effect was achieved. Note: The cleaning agent can be recycled and reused, and the discharge will cause waste. 8. After reaching the cleaning time, recover the cleaning solution. And repeatedly rinse the exchanger with clean water until it is cleaned to neutrality. Use a pH test paper to measure the PH value of 6-7. 9. After cleaning, it can be turned on and run. You can also press test to see if there is any leakage. If there is a leak, polymer composite materials can be used for repair and protection, and the service life of the equipment can be greatly extended. ⒑ After the equipment is stable, write down the current medium flow rate, working pressure, heat exchange efficiency and other data. ⒒ Comparing the changes in the values u200bu200bbefore and after cleaning, we can calculate the electricity, coal and other production costs that the company has saved every hour and the increased work efficiency. This is exactly the value compensation for the company's application of technology. 12. The same method of operation can also be used to clean condensers and frame heat exchangers. ⒔ If the company needs equipment for passivation pre-filming treatment, it can operate according to the following process: pump the passivation pre-filming agent into the equipment according to the recommended dilution ratio (at the same time hang the test piece in the circulation tank); cycle and soak according to the recommended time ; Detect the effect of pre-filming (red dot method or blue dot method); discharge; rinse with water to neutral (measure PH value 6~7 with PH test paper). ⒕ After the passivation pre-filming, try to use fans and other ventilation equipment to dry the system to ensure and improve the passivation pre-filming effect.