Pulp, paper and wood

Improve manufacturing productivity at every stage

Vaisala's in-line dry solids content, and humidity and temperature measurement solutions support the sustainability and performance requirements of wood-based forest industry in a broad range of applications. Our technologies help paper chemical companies, kraft chemical and semi-mechanical pulp mills, and paper and wood mills achieve high efficiency and essential properties in pulp, paper, paperboard, wood and timber products. 

You may click on a link to discover supported applications and impact in each of these four categories: Pulp chemical recovery, brown stock washing, paper making and wood and timber processing.

Recovery boiler-burners, refractometers in black liquor feed to recovery boiler

Inline process control applications in the kraft chemical recovery

Although the kraft recovery process is straightforward in principle, it is not easy to operate at high efficiency without proper process measurements. We provide retractable Vaisala Polaris PR53SD Process Refractometers for measuring black liquor and green liquor dry solids, liquid density, concentration, and Total Titrable Alkali (TTA) in chemical recovery process to optimize energy-intensive operations. As a result, the capacity of the evaporators can be increased, and the quality of white liquor can be improved by controlling continuously the TTA of the green liquor in the causticizing process. Furthermore, recovery boiler safety can be increased using a Digital divert control system in feeding black liquor solids to recovery boiler burners.

Vaisala K-Patents safe drive refractometer in Brown stock washing installation

Inline process control applications in fiberline and brown stock washing

Brown stock washing (BSW) can be considered the key operation influencing the economics of the pulping process, as well as the environmental load of the mill. The purpose of brown stock washing is to remove both organic and inorganic soluble compounds from the pulp suspension (brown stock), while using the lowest possible amount of wash liquor or water. Vaisala provides Process Refractometers for measuring and monitoring the Total Dissolved Solids (TDS) content in the pulp suspension. 

Through optimization of the brown stock washing process and raising the black liquor solids content, mills gain immediate profits, cleaner and better quality pulp for bleaching, as well as optimized use of water, chemicals and energy.

Paper mill

Inline concentration measurement of sizing liquids and humidity measurement in paper mill

In paper manufacturing it is important to control the paper sizing process as well as moisture content in the paper to an optimal level based on the end-use e.g. printing. 

Vaisala provides Process refractometers for the preparation and use of the size liquids, to ensure the right concentration of the cooked starch to storage, and to help stabilize sizing conditions and paper quality.

Learn more about concentration measurements in paper sizing

Typically, the paper mass is not measured directly, but paper mills use the hood air measurement to monitor and control the drying process indirectly, to avoid excess humidity in the hood. This measurement is especially demanding if there is a risk of condensation combined with elevated temperatures.

Timber drying

Wood and timber drying

Wood drying is a complex process where measuring relative humidity plays an important role. Save energy and reduce costs by monitoring the humidity in your processes to avoid over-drying products and wasting energy. For accurate measurements, use the appropriate sensor, install the measurement device correctly, and calibrate the device regularly. Try our Drying Simulator below to calculate your cost savings or learn more about