A Novel Approach to Lignocellulosic Utilization for Energy, Chemicals, and Composite Panels

摘要

The expansion of wood-based products into new markets has been accompanied by a constant series of improvements in the urea-formaldehyde, phenol-formaldehyde, and isocyanate binders. This paper presents a new system that allows for continuous processing of raw materials into a self-binding furnish for composite materials. The Convertech system is a cost-effective, energy-efficient, linear thermal processing technology for converting lignocellulosic residues into a wide variety of end uses including horticultural and animal feed applications, energy generation, chemical extractions and conversions, and raw materials for composite panels. The system is a multiple-effect treatment unit utilizing a series of processing loops of increasing temperature. Energy is recycled to produce a highly energy-efficient system. A new transfer device has been developed to move the material into successive loops at high-pressure differentials. Chemicals are removed in various stages and moisture is removed in the final stage with a dry product issuing from the system. If used as fuel, almost all potential energy is reclaimed since little is lost in evaporation of moisture. This attribute, combined with low drying cost, produces the most effi- cient wood/lignocellulose energy system available. Furfural, a valuable commodity chemical used in plastics, can be produced in significant quantities from the hemicellulose byproducts of the system. As a process for producing raw materials for composites, the dry fiber product combined with furfural provides a self-bonding mat under heat and pressure. The low-cost raw materials and self-bonding characteristics offer new dimensions to the composite panel industries.