Plate heat exchangers

Cleaning of plate heat exchangers

Plate heat exchangers have a crucial role in various operational processes. It is therefore extremely important to keep these systems in good condition. A fouled plate heat exchanger will be less efficient and still consume the same level (or even more) energy. In addition, the lifespan of the installation and components can be shortened by keeping it in a fouled condition.

Current cleaning techniques

At the moment many end customers and contractors still use the traditional cleaning method of cleaning plates manually with high pressure washers. In this case, the entire system has to be disassembled and the plates are cleaned piece by piece, sometimes also mechanically brushed. This is an intensive job and can easily take a few days. The costs for this cleaning technique are often high, due to the following factors:

• Disconnecting and disassembly of the system
• Transport of the plates to an offsite location for cleaning
• Manual cleaning of the plates, piece by piece
• Checking plates for hairline cracks caused by high pressure cleaning
• Replacing gaskets of the plates
• Reassembly of the system

By combining the above points, their associated costs and the total downtime, it is understandable that some companies try to postpone the cleaning as much as possible. Postponing the cleaning ensures that the deposit is able to increase over time. This can lead to a degree of deposits that is so high that mechanical cleaning is the only option. The longer the cleaning is postponed, the worse the efficiency of the installation will become, with all its detrimental consequences. Think of: increased energy consumption at less efficiency, malfunctions of the system and the like.

Cleaning-In-Place (CIP)

In many cases it is possible to clean plate heat exchangers using the CIP (clean-in-place) procedure. In this technique, a flushing pump is used to circulate a chemical cleaning agent through the plates of the heat exchanger. A CIP is a very simple and effective technique, especially with a preventive cleaning and maintenance program in place. On this page you can find more detailed information about how a CIP works.

With a CIP program, more cleanings will take place on an annual basis than with a mechanical cleaning. However, despite the higher frequency of cleaning, this technique is a lot more affordable for the customer and better for the system. This is due to the following factors:

• Less manpower required, because the system does not have to be disassembled.
• Shorter downtime, because the system does not have to be disassembled. In some cases, the total downtime due to cleaning can be up to 80-90% shorter. Of course, this also has a direct link with cost savings.
• Cost savings because gaskets do not have to be replaced. The lifetime of the gaskets is reduced by 50% when the plate heat exchanger is disassembled. This is due to the compression and decompression of the plates.
• A preventive CIP program keeps the plate heat exchanger in optimum condition. Due to the high cleanliness of the system, it is possible to ensure a stable, high efficiency close to the original values. High cleanliness also contributes to a longer lifetime of the system and the internal components, such as the gaskets.

A good combination of the cleaning agent, the mix ratio and the type of flushing pump will ultimately determine the cleaning result of the CIP. That is why you should always consult an expert before carrying out a cleaning-in-place.

Scalebreak-MP cleaning agent

Scalebreak-MP (multi-purpose) is the most widely used chemical cleaning product of Goodway Benelux. This is because it is hazardous-free, biodegradable and can be used on almost any material. In addition, gaskets remain unaffected during cleaning with Scalebreak-MP, so little or no new parts are needed. Some types of materials which are unharmed by Scalebreak-MP are:

• Brass
• Copper
• Nickel
• (Stainless) steel
• Rubber