Revamp Forced Circulation Evaporator Waste Water Stream

Klaren International specialises in the revamp of heat exchangers. Our innovative technology provides a self-cleaning configuration. We take care of the entire process – design, manufacturing and commissioning – for the revamp of the heat exchanger at your facility. This method is specifically suitable for highly fouling equipment, such as evaporators and crystallizers and greatly reduces maintenance costs. Learn more about our revamping approach of an extremely fouling evaporator.

Ref Revamp Forced Circulation Evaporator
ApplicationForced Circulation Evaporator Waste Water Stream
IndustryDyes Manufacturer
Fouling Issue / Frequency

The evaporator being revamped was the 1st effect of a 4-effect evaporator train to treat waste water from a plant that produces dyes for textile. This 1st effect experienced severe fouling by crystallization of a variety of sulfate salts. Effect 2 to 4 experienced some fouling but to a lesser extent. Due to fouling, within only 20 days of operation, the plant regularly lost more than 50% of its treatment capacity.

Solution / Approach

For the revamp into the self-cleaning configuration, the heat exchanger was equipped with an inlet channel to feed the particles and distribute them over all tubes. In between the heat exchanger outlet and the entrance of the flash vessel a particle separator was installed to separate the particles from liquid and transport them via a central down-comer back to the inlet. In the revamp the existing heat exchanger bundle was re-used, changing it from a 3-pass into an once-through configuration.

Process ConditionsTubeShell
MediumWaste Water Dyes ProcessCondensing Steam
Pressure2.2 bara1.59 bara
TemperatureIn: 107oC
Out: 108.63oC
In: 113.20oC
Out: 112.58oC
Flow900 m3/h2659 kg/h
Duty1646 kW



Number of Tubes


Length of Tubes

6 m

Diameter Tubes

34.9 mm (ID)

Particle Type


Particle Size

3 mm

After taking the plant back into operation, the evaporation capacity kept constant, which results in increased production, lower downtime and reduced maintenance cost.

Method for the revamp of heat exchangers

We work according to a fixed approach for the revamp of heat exchangers. Firstly, a technical feasibility study will reveal whether the revamp of your equipment, such as an evaporation system, into a self-cleaning configuration is possible. This depends on a number of factors, such as the layout and dimensions of the existing installation. The optimizations will then be visualized in a design, after which the required components will be manufactured in order to convert the existing unit. We will apply and realize this for your company from start to finish.

Receive more information

Would you like to know whether it is possible to have your heat exchangers converted into self-cleaning installations? Then please contact our office in the Netherlands by phone at +31 85 27 34 834 or send an e-mail to Our services are available globally.