Morton Controls

SENSOTECH – Green & Black Liquor Treatment in the Pulp & Paper Industry

Morton Controls

SENSOTECH – Green & Black Liquor Treatment in the Pulp & Paper Industry

In the pulp and paper industry, one process is the alkaline sulphate process, where lignin needs to be separated from the fibrous material.  The chemicals which are used in this process, need to be recycled.

To better monitor each step in this process, from black liquor to green liquor, and finally to white liquor, LiquiSonic® analyzers from Sensotech work perfectly.

With LiquiSonic®, one can follow a quality control plan that will increase productivity.


LiquiSonic® measuring technology allows the company real-time monitoring, green liquor generation, regulated and optimized, so that quality and precise results are born.

The base material in the liquor recycling process is black liquor. While burning an inorganic salt-rich smelt is formed, sediments form on the ground of the recovery boiler and have to be diluted by water or weak white liquor. The result of this process is green liquor, rich in Na2S and Na2CO3. The green liquor is often collec­ted in a separate stabilizing tank before it is clarified. While clarification of green liquor takes place, dregs have to be removed. The clarified green liquor is used for causticizing of regenerate NaOH.


The advantages of utilizing the LiquiSonic® technology are numerous:

  • Accurate inline concentration measurement of green, white and black liquor
  • Easy to clean
  • Operational safety is enhanced
  • Maintenance free
  • Ideal lime dosage
  • Reduced laboratory costs

LiquiSonic® sonic velocity measurement in green liquor


The LiquiSonic® flange sensor has an easy installation process for pipelines transporting green liquor.

With the LiquiSonic® controller 30, you can connect up to 30 sensors, so in this way multiple measuring points can be monitored:

  • after dilution tank
  • after stabilizing tank
  • after clarifier

LiquiSonic® 30


Contact Morton Controls for more on this innovative product from Sensotech.

TELEPHONE: 0861 000 393