• The client’s objective was to neutralize the pH value of the exhaust gases in the scrubber, before they enter the activated carbon filters.

  • Design of a pH neutralization system.

  • Installation of pH measuring devices.

  • Design and installation of a dosing system for sodium hydroxid.


  • Saen Engineering was selected to provide the engineering, project management and operator training for this project.

  • Two pH-measuring devices were installed in the inlet and outlet of the gas cleaning system.

  • A pump was installed, connected to a tank of NaOH and to the gas cleaning system.

  • The system was added to PCS7. The software regulates the pump based on the pH values.


  • Saen Engineering designed and installed the system within two working days.

  • Overall safety has improved because operators no longer have to dispense NaOH by hand.

  • The pH is always neutral because of the PID regulator in the software.

About the project

The client uses hydrochloric acid in its production process.
Therefore, the continuous monitoring of the pH value in emission gases of the gas scrubber
is highly important to ensure that no acid gases are emitted.

Project details

  • Confidential client

  • The Netherlands

  • ~10.000