Bivis machine cellulose pulp Twin-screw processing and production systems, developed by Clextral for over 30 years, enable paper-industry manufacturers to produce high-quality cellulose pulp economically and ecologically. Clextral systems are designed to reduce pulp production costs and environmental impact, featuring low-chemical pulp processing and minimum water consumption.

Specific products, such as writing paper, cardboard and banknote paper can be made using a wide variety of raw materials, including softwood and hardwood, textile fibers, annual plants, agricultural waste products and recycled fibers.

Practical information

Linen fiberTwin-screw Bivis pulping is based on the use of a co-rotating twin screw at the heart of the system. The primary advantage of this system is its ability to process very long cellulosic fibers and fiber bundles  to produce pulp with controlled fiber lengths and distribution features.

Clextral systems ensure fiber defibering, chemical impregnation, washing and bleaching to obtain custom-designed pulp to produce papers for a wide variety of applications, from high-quality banknotes to bulk cardboard, via special writing papers and molded fibers .technology.

A wide selection of raw materials can be used, including:

  • Softwood and hardwood
  • Cotton fibers and cotton textile wastes
  • Annual plants such as hemp, flax, manila hemp, sisal, jute, kenaf , miscanthus and other fiber plants
  • Wheat straw and other agricultural waste products, such as sugar cane or corn stover
  • Other non-wood materials such as oil palm tree fibers, sorghum, etc.
  • Recycled Fibers

The advantages of twin-screw systems for pulp processing

  • Production of specific pulps for a wide variety of applications
  • Versatility in the use of wood and non-wood raw materials 

  • Cost effective and environmentally-friendly, compared to conventional processes,
    • 10 to 15% reduction in energy consumption for fiber separation
    • 10 to 30% decrease of chemicals and bleaching agents
    • Reduced water consumption, from 30% up to 90% for certain pulp processes
  • Shorter manufacturing time, thanks to continuous processing
  • Quick and easy maintenance, reduced down time and changeover

Clextral also offers its expertise and inhouse R&D facilities to enable papermakers and research centers to develop and test new concepts and improve processing.