There are 16 factories that manufacture particleboard in Japan (April, 2006). In October, 2006, total domestic production was 1,234,000 m3 and imported particleboard production was

391,0 m3. Of this total (1,625,000 m3), 60% was used for furniture and 37% was used for construction. To meet the goals of Japanese laws for recycling 60 % dismantled construction wood, 61% of raw materials for wood composite panel manufacturing was from dismantled waste in 2005.

3.3.2 Particleboard Manufacture

The process of particleboard manufacture is shown in Fig. 3.3.1. The first stage of the process is manufacturing raw particles from the mixture of waste wood, which is described as “particle formation process.” Dismantled construction wood and industrial waste wood are processed on different lines in the particle formation process. Several processes are performed for reducing bulk wood to chip size and eliminating foreign materials. Raw materials are sent to a shear crushing machine for initial size reduction, metal is removed by magnets, and the material is then further reduced in a hammer crusher. Material is screened and sorted by airflow, eliminating sand and concrete. The remaining raw material is sent through a search-coil magnetometer, which eliminates non-metal foreign materials. The second stage of the process is to manufacture board from the raw particles created by the first process. To obtain uniformly thick particles, a ring flaker is used for particle size reduction. the particles are then dried and screened. Energy for the drying kiln is often supplied by burning dust produced in the plant. The particles are classified by size prior to blending them with adhesive. Separate surface and core blenders are used for three-layered particleboards. The blended furnish is moved to the three mat formers, hot-pressed, cured, and sanded. Nondestructive testing is sometimes performed to eliminate products that include defects, such as blisters. After sanding, products are inspected for shipping.