Heat Exchangers and Cleaning Systems for Industrial and District Heating

PTI A/S offers design and construction of heat exchanger systems, optionally with an integrated cleaning system (CIP System).

Based on many years of experience with heat exchangers for dairy products and other foods, we have built up solid experience with the many challenges that can arise when heat exchange is required.

In addition to dairy products and foods, we have experience with the heat exchange of both clean and slightly polluted water. For example, PTI A/S has designed a system for extracting recycled heat from wastewater for the intermediate circuit of a heat pump system for Rødkærsbro District Heating Plant.

The challenge with heat exchange is that the heat transfer surface becomes dirty over time, which leads to a significant deterioration in the heat transfer coefficient. When this happens, the efficiency of the heat exchanger decreases, and the operational economy of the process worsens.

In such situations, automatic cleaning at fixed intervals can improve the operational economy of the system and minimize the maintenance of the heat exchangers. By keeping the heat exchangers clean with automatic interval cleaning, manual disassembly of the heat exchangers for cleaning can often be completely avoided.

Cleaning is a necessary but, in principle, unwanted expense. Therefore, efficient cleaning is very important for operational economy. However, the concept of “efficient cleaning” is relative to the cleaning task that needs to be addressed.

To achieve the optimal balance between capital costs and operational costs, a cleaning process must be planned and designed into the process plant while it is still at the drawing stage. A well-thought-out mechanical/flow technical design can, in many cases, drastically reduce the ongoing cleaning costs throughout the life of the plant.

Automatic cleaning is performed according to the CIP (Cleaning In Place) principle, where cleaning fluid is circulated over the heat exchangers. For this to be effective, each system must be analyzed, and the cleaning process designed to suit the task. An inappropriate design of the cleaning process can easily result in inefficient or inadequate cleaning, leading to significant additional costs throughout the life of the plant.