Chemical plate cleaning - plate heat exchangers become dirty over the years
Why is chemical plate cleaning so important and sensible? Heat exchanger plates tend to form deposits due to diverse media contamination. This reduces the efficiency of plate heat exchangers and increases energy costs. In order to guarantee optimum operation of the plate heat exchanger, we, AKK Industrieservice & Handels GmbH, have developed a process to subject heat exchanger plates to optimum refurbishment. In cooperation with chemical suppliers, we have developed special acid and caustic baths for this process.
How does chemical plate cleaning work?
First, the stainless steel plates are placed in a heated caustic bath to remove the gasket. The adhesive dissolves under the influence of temperature and caustic so that the gasket can be removed without great mechanical effort. At the same time impurities on the plate are dissolved.
For this purpose, the gaskets are removed from the plates and, depending on the type of contamination, treated in a heated caustic or acid basin for 4-6 hours. In these special immersion baths, adhesive residues and coatings are dissolved simultaneously. The plates are then cleaned of remaining adhesive residues, deposits and chemical residues under high pressure.
We are specialised in the chemical cleaning of plate heat exchangers so that the chemicals used do not attack the stainless steel surface. This ensures that after chemical cleaning there is no greater surface roughness than before cleaning. In non-specialised companies this is usually not guaranteed.
If unsuitable chemicals are used, the metallic surface can become dull, resulting in faster coating formation and higher energy costs.
The subsequent steam jet cleaning removes incrustations and adhesive residues from the plate. If necessary, for example to remove any calciferous deposits, the plates are then additionally treated in an acid basin.
Then, a high pressure cleaning is carried out to thoroughly remove the residues of the cleaning chemicals from the heat exchanger plates.
Advantages of the method
After this treatment the plates are metallically clean. The chemicals we use do not attack the stainless steel surfaces of the heat exchanger plates! The resulting waste water is treated in our own water treatment unit in accordance with the strictest environmental regulations.