To clean plate heat exchanger plates effectively, several methods can be employed depending on the level of fouling and the specific requirements of the heat exchanger. Here are the primary methods detailed in the sources:
1. Chemical Cleaning
Chemical cleaning involves using specific chemicals to dissolve and remove fouling from the plates. This method is particularly useful for removing hard and stubborn deposits that cannot be cleaned by water alone. Chemicals such as nitric acid and corrosion inhibitors are recommended for stainless steel plate heat exchangers to avoid damage to the material[2][3]. It’s important to ensure that the chemicals used are compatible with the materials of the heat exchanger to prevent corrosion.
2. High-Pressure Water Jetting
This method uses high-pressure water to physically remove deposits from the plates. It is effective for removing loose and less adherent types of fouling. High-pressure water jetting can be used alone or in combination with chemical cleaning to enhance the cleaning effectiveness.
3. Manual Cleaning
Manual cleaning involves disassembling the heat exchanger and cleaning each plate manually. This method is labor-intensive but allows for thorough cleaning and inspection of each plate. It is recommended to use soft bristle brushes and avoid metal brushes which can damage the surface of the plates. After cleaning, the plates should be rinsed thoroughly to remove any residual cleaning agents.
4. Cleaning in Place (CIP)
CIP is a method where cleaning solutions are circulated through the heat exchanger without disassembling it. This method is less disruptive and can be effective for routine maintenance cleaning. The effectiveness of CIP depends on the correct choice of cleaning solution, temperature, flow rate, and contact time.
5. Backflushing
Backflushing involves reversing the flow of the cleaning solution through the heat exchanger to dislodge and remove debris. This method is particularly useful when the exchanger is prone to clogging from particles in the system.
6. Disassembled Cleaning
For severe fouling, disassembling the heat exchanger and cleaning the individual plates might be necessary. This allows for detailed inspection and cleaning of each component. Care should be taken to handle the plates and gaskets properly to avoid damage.
Additional Tips:
- Always follow the manufacturer’s guidelines for cleaning to avoid damaging the heat exchanger.
- Inspect gaskets and seals during cleaning and replace them if they are damaged to ensure proper sealing when the heat exchanger is reassembled.
- After cleaning, it is advisable to perform a leak test to ensure the integrity of the heat exchanger before putting it back into service.
These methods provide a comprehensive approach to cleaning plate heat exchanger plates, ensuring that they operate efficiently and have a prolonged service life.
