Breakthrough for a cleaner paper industry

A new approach that makes paper from straw, which is said to be both cheaper and greener, is one step closer to reality thanks to an investment award of £90,500 from NESTA (the National Endowment for Science, Technology and the Arts) to Surrey, UK-based environmental company, BioRegional MiniMills.

There are reported to be nearly 9,000 paper and board mills worldwide, and the demand for paper is growing at a rate of 3% per annum. Current mills are huge operations run by multi-national companies. However, MiniMills´ new process would allow more independent paper makers to compete with these large-scale processes. Their method would facilitate the use of a greater variety of raw materials, including straw – four million tonnes of straw goes unused in the UK annually – and wood from sustainably-managed, smaller woodlands for use in paper-making. This would provide income generation for both farmers and foresters.

The new process also provides a more efficient and ecologically sound method for treating effluent, otherwise known as ´black liquor´, from the pulp-making procedure. Current processes for effluent treatment are carried out at high temperatures which requires high levels of energy.

MiniMills´ method liberates organic matter present in the black liquor and recycles this as process fuel, as well as recovering sodium hydroxide for re-use in pulping. The reactions take place at relatively low temperatures.

Since 1997, pilot-scale laboratory trials have been carried out with support from six paper companies, two environmental charities, the Ministry for Agriculture, Fisheries and Food (MAFF) and the Department for Trade and Industry (DTI). Having reached the proof of concept stage, the next vital step for MiniMills is to build a £6m demonstration plant. NESTA´s support will go a long way in helping the organisation achieve this aim as well as enabling them to secure intellectual property rights (IPR) and provide legal and technical expertise.

Earlier this month, the team held open days of at the black liquor treatment plant at Frogmore Mill in Hemel Hempstead. Excellent feedback was received from members of the paper industry who were invited to observe the black liquor treatment plant in operation and discuss the potential for becoming partners to commercialise and promote the technology.

The latest trials show that the BioRegional MiniMills offer improved drainage, less fibre damage and faster pulping. The process uses technology tried and tested in other areas of manufacturing such as food and industrial waste processing, and therefore the technical risk is minimised.