Kraft (Sulfate) Pulp: Continuous Digester

Kraft pulping process involves cooking. In cooking, the chips and the cooking liquor are fed into a digester for pulping reaction to take place under pressure and high temperature. After cooking, the pulp passes through blow line to the blow tank and then to washing section where diffuser washers separate the black liquor from the fibers by washing them with washing liquor or water.

TDS measurement of pulp suspensions in digester washing zone and blow line

Download our application note to learn how Vaisala Polaris SAFE-DRIVE Process Refractometer PR53SD can help pulp mills to:

• Increase washing efficiency
• Obtain consistent pulp quality
• Reduce bleaching chemical consumption and environmental load
• Increase evaporation efficiency.

The SAFE-DRIVE Refractometer measures in real-time the Total Dissolved Solids (TDS) content in the blow pulp suspension after the digester. Together with other measurements (e.g. filtrate and flush liquor) this provides the mill with the ability to control the performance of the washing zone in the digester. In addition, TDS measurement in the blow line allows the performance of the digester to be monitored, ensuring that it yields the correct concentration. The combination of these measurements facilitates continuous calculation of the mass balances of the digester.

Download the application note in PDF by filling the form.

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