An initiative undergoing trials this summer is set to make pulping of non-wood fibres for paper production commercially viable.
The BioRegional Development Group, backed by the Department of Trade and Industry and Surrey University, is planning to transfer its clean BioRegional MiniMill technology to China, where untreated effluents from pulping cause serious environmental problems.
The MiniMill, designed to process crop fibres, wood and recovered fibres, also has applications in countries with excess non-wood fibres, such as the UK, which has a surplus of about 4 million tonnes of cereal straw a year.
The MiniMill uses clean technology for raw material preparation, pulping, bleaching and chemical recovery. It will be able to process between 10 and 100 tonnes of pulp a day.
The trials will evaluate a method of opening stems to allow efficient pulping while preserving fibre length.
The MiniMill’s other features include: an improved feed system for twin or single-screw pulping; a twin-screw system to improve pulping of long fibres; a process which burns waste liquor cleanly, producing heat and energy and directly recovering the pulping chemical; and a non-chlorine bleaching system.
Environmental bodies and firms taking part in the trials include the Central Science Laboratory, Silsoe Research Institute, Molins, the Wolfson Centre at Brunel University, Dassett Process Engineering, Torftech, BP Chemicals and QPS Consultants. The first MiniMills being built at some of these centres will act as demonstration units.