Vaisala Polaris PR53SD Process Refractometer

Optimize your pulp industry processes with the Vaisala Polaris PR53SD Process Refractometer model, designed to measure tough liquid concentrations in fiber and chemical recovery lines, such as black liquor, green liquor, and brown stock washing. With a retractable design, the PR53SD enables reliable measurement and service without process shutdown, minimizing downtime in the measurement process.

Safety is a top priority, and the modern SAFE-DRIVE retractor system integrates the process refractometer and the retractor as one simple system, preventing inadvertent errors and ensuring the isolation valve is closed before the instrument is removed. The system is easy to operate, and the PR53SD instrument is suitable for critical and safety measurements in pulp mills.

Vaisala’s retractable refractometer with a wash nozzle for green liquor is unique in the world, offering accurate inline measurements even with high solids concentrations up to 85% in black liquor. Contact our special partner network for commissioning and start-up assistance.

Available: ONT

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Pulp, paper and wood

Vaisala’s inline dry solids content, and humidity and temperature measurement solutions 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. Explore our full offering and applications.

Key Benefits

  • Critical and safety measurements in pulp mills
    The process refractometer design is in compliance with the BLRBAC Recommended Good Practice Safe Firing of Black Liquor in Black Liquor Recovery Boilers.

  • Measure in all process conditions
    Product measures reliably in various process conditions, including high heat, sticky process, rapidly changing process condition and with particles or fibers in the process.

  • New, safe and simple design for the SAFE-DRIVE retractor
    Insert and remove from the pressurized process line. The SAFE-DRIVE retractor design prevents inadvertent errors in use.

  • Total dissolved solids, the only true measurement of organics and inorganics
    Weak liquor and black liquor are a mixture of cooking chemicals and dissolved organic material. The RI measurement responds to all dissolved solids. Bubbles, foam, particles, suspended solids or fibers do not affect measurement.

  • Plug & play to Indigo520
    Expand features, including wash control, data storage, graphical interface, analog and digital interface by connecting to Vaisala Indigo520 transmitter. Convenient service with the Plug & play feature with minimized downtime should service be needed.
  • Customizable product with our Engineer to Order service
    Big pipes, small pipes, spool pieces, washing system, spare parts, specific drawings? When one size does not fit all, Vaisala can tailor products to fit your specific needs.Contact us for options!



Manufacturer info

Today, Vaisala is a global leader in weather, environmental, and industrial measurements headquartered in Vantaa, Finland. Building on over 80 years of experience, Vaisala strives towards its mission of Observations for a better world.