Introduction

The objective of the project is to develop a "natural' resin to be used in for bonding wood materials in the production of wood panel products. This would be used to replace all the fossil fuel derived phenol and a major part of the formaldehyde content of synthetic resins with renewable biomass-derived thermolysis liquid or concentrates obtained therefrom. The aims are to substantially improve on the 50% phenol substitution already achieved, solve the known odour problem of the liquid by pre-treatment and/or in-situ reaction, enhance the reactivity of the thermolysis liquids by process modification, and demonstrate the process at a commercial scale. The ultimate project target is to develop a closed loop technology for the panel industries by thermolysing their process wastes to obtain an efficient substitute for the resin they apply for panel bonding. The whole production chain will be investigated from biomass supply through thermolysis and resin production using the liquids obtained, to laboratory and large-scale production of a range of wood products. The test programme will comprise liquid production under different conditions, from different feedstocks and from different reactors. Technical, economic, environmental, safety and market feasibility studies will examine the commercial opportunities.

Objectives

The overall aim of the project is to attempt to replace all the synthetic phenol and a major part of the synthetic formaldehyde in the fossil fuel derived synthetic resins used in the wood based panel industry with improved biomass derived thermolysis liquid. The detailed objectives are as follows:

• The known odour problem will be overcome either by pretreating the biomass feed or by in-situ reaction
• The reactivity of the thermolysis liquids will be enhanced by modifying the reaction parameters and process
• Liquids from different biomass types and from wood panel process wastes will be produced under different conditions from at least two reactor types
• Thermolysis liquids will be subjected to simple separation processes to concentrate the active components
• Each liquid and concentrate will be tested in the laboratory as a substitute for both phenol and formaldehyde in resins The most promising products will be selected for larger scale testing at pilot and commercial scales of wood panel production on Oriented Strand Board, Medium Density Fibreboard, Plywood, and High Pressure Laminates.
• The process and product will be assessed technically, economically, environmentally and for market opportunities.

The benefits from this substitution are the use of bio-based resins to replace synthetic products and decreased dependence on petroleum.

Description of the work

The project aims to increase the replacement of the phenol and formaldehyde used in the production of resins for the wood panel industry to 100% and over 30% respectively with biomass derived thermolysis liquids by enhancing the reactivity of the liquid and by separating or concentrating the active fractions. In addition, the known problem of liquid odour will be addressed by biomass pre-treatment and by in-situ reaction. The liquid will be produced from wood (forestry waste) and process wastes from the wood panel industry. To control the odour problem, liquid samples will be also produced from material that has been pretreated to reduce alkali metals and hemicellulose by pushing the reaction pathway towards de-polyrnerisation rather than fragmentation. In order to optimise the production conditions and enhance liquid reactivity, the liquid will be produced over a range of temperatures, at various vapour residence times, with additions of oxidant and from two reactor systems. The liquid will be subjected to simple separation processes to concentrate the active fractions. It will not be possible to explore every combination of processing option so a representative selection will be made based on factorial experimental design. The liquid will be analysed and characterised. The resultant liquid products will be used to produce resins from which test boards will be made in a laboratory and evaluated for meeting international standards. The most promising resins will then be tested at large scale by leading European companies in each sector on four major wood panel products - MDF, Plywood, OSB and HPL. The products will be thoroughly evaluated. Finally a detailed process design will be produced.

Milestones and expected results

• Successful production of thermolysis liquids with less odour
• Successful production of liquids with enhanced reactivity
• Successful separation of liquids into active components
• Successful maximum substitution of synthetic phenol and formaldehyde in resins at laboratory scale
• Successful test results on panels at industrial scale
• Viable process design and completion of Life Cycle Assessment
• Creation of a viable business plan
• Efficient renewable wood adhesives, significant cost savings, increased European competitiveness and higher employment in the resins and wood panel industries.
• Optimum thermolysis liquid will be prepared including any necessary additional processing that may have been identified.
• Production cost estimates will be derived for the liquid modified resin and compared with the cost of conventional fossil fuel derived materials.
• Life cycle and safety assessments will be carried out and a market evaluation for the renewable resin will be produced.

Contacts

Coordinator

• A V BRIDGWATER / Aston University Bio-Energy Research Group / UNITED KINGDOM

Participant

• Effy MARKESSINI / Adhesives Research Institute Ltd / Marlit Ltd GREECE
• David PACKHAM / Aston University UNITED KINGDOM
• Dieter ECKSTEIN / Bundesforschungsanstalt für Forst un Holzwitschaft GERMANY
• Bernhard PELZI / Joanneum Research GesmbH Institute of Energy Research / AUSTRIA
• Keith PHILLIPS / TRESPA International B.V. Trespa Technology Centre / NETHERLANDS
• Valbopan Fibras de Madeira SA PORTUGAL