A brazed plate heat exchanger is normally self-cleaning, thanks to highly turbulent flows. In applications with a high risk of fouling or scaling, e.g. due to high temperatures, hard water, or high pH levels, cleaning may be required to maintain efficiency. This is achieved quickly and easily with Cleaning in Place (CIP). This is a method of cleaning the interior surfaces of closed systems, such as pipes, vessels, process equipment, and filters, by circulating a liquid. Disassembly is not required.
When is cleaning required?
Fouling and scaling will increase the pressure drop and insulate the heat transfer surface, thus reducing the efficiency of heat transfer. Indicators of the need to clean your heat exchanger are temperature differences smaller than specified (as a result of fouling of the channel plate surface, reducing heat transfer), or pressure drops higher than specified (due to scaling constricting the channel passage and thus increasing velocity).
How do I clean a SWEP heat exchanger?
A SWEP heat exchanger is cleaned by circulating a cleaning liquid through it. Disassembly is not required. You can equip your BPHE with customized CIP ports to make it even easier. Our calculation software SSP offers a Pressure Drop tool, which can be used to determine when an installed BPHE needs cleaning by comparing the measured pressure drop data with the expected performance of a clean BPHE. An increase of 30% or more indicates cleaning is needed. Please contact us to discuss CIP port solutions, or for advice on the cleaning agent and equipment best suited to your application.
Tap water with extreme hardness – a case story
Ringsjön is a lake in southern Sweden from which tap water is drawn. The very hard water (dH 11) results in scaling on the equipment used. After 4-6 years' operation, the SWEP heat exchangers used for heating the tap water were returned to SWEP. The purpose was to observe how the still fully functional heat exchangers had been affected by the hard water, and to evaluate a biodynamic CIP fluid for removing carbonates and metal oxides without the risk of corrosion. Thermal and hydraulic performance tests were conducted before and after CIP treatment on the tap water side. The test results showed improvements in thermal performance by 5% and in hydraulic performance by 2%. A visual inspection confirmed that the limescale and metal oxides were completely removed, and testing confirmed that there were no internal or external leakages.