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Heat exchanger

heat exchanger headerNot only influence-able parameter such as the water quality and temperature in a heat exchanger, are responsible for fouling or scaling inside a heat exchanger. As well not direct influence-able parameter, as details of construction of a heat exchanger, the design of the water loop (material, open/closed system, blow down) have a significant influence on cleaning cycles

MERUS stops or reduces the process of fouling in a heat exchanger. Details and our experience from the field see at the table below. Depending on the application and the design of the to be treated system, Merus Rings are either installed direct no the feed-line of the heat exchanger or in the case of a entirely treated cooling loop, it is not necessary to treat each single heat exchanger separately.

The design of a heat exchanger and its hydro dynamic quality are responsible, how fast and how strong fouling take place in a heat exchanger. Tubular heat exchanger have in general a better hydro dynamic design, because mostly a laminar flow inside is achieved. The somewhat less expensive plate heat exchanger have due to the design, inside areas where there is less flow. In these areas with poorer flow, the fouling starts first and layers of calcium or other mineral start to build. Starting from this parts, the heat exchanger start to close and finally has to be cleaned. Integrated heat exchangers (e.g. cooling in a motor) have very often an unfavourable flow characteristic and has to be cleaned most often.

Merus is world wide, successfully used in thousands of heat exchangers. The major applications are heat exchanger in cooling loops, heat exchanger for compressors, heat exchanger for air conditioning systems, as well as integrated heat exchanger in mold forms, machines and motors.
Lately Merus is treating Heat exchanger in the oil industry, where hydro carbons are heated or cooled. Even in this very critical applications improvements are observed.
See for this topic also www.merusoilandgas.com/fouling.
The proper monitoring of the fouling or better the condition of the heat exchanger is essential to Merus and its customers. Merus is therefore regularly measuring the heat transfer coefficient of the heat exchanger, if there are the required data supplied. We provide our customers with trends, and are in the case of technical problem able to react very early and prevent eventual arising problems.
The picture to the right shows how the header of a two pass tubular heat exchanger got automatically cleaned in only 8 weeks time, without using any chemicals or mechanical action.



Table: Experience values - reducing service cycles at heat exchanger

tubular heat exchanger

plate heat exchanger

integrated heat exchanger

no more cleaning required

65%

35%

15%

cleaning cycles 5 times expanded

25%

50%

55%

minor difference in cleaning cycles

10%

15%

30%


The above shown values are valid for water with not more than 1500 TDS* and temperatures until 100° Celsius. At higher TDS rates the success rates might be lower accordingly. Fouling caused by product or remaining of product, are as well able to be treated by Merus Rings, but these has to be discussed separate.

*TDS - Total Dissolved Solids