Process solutions to identify delamination at the plywood panel processing stage
Issue: Different types of defects occur during manufacturing and processing of plywood. Delamination is one of them. Delamination means ungluing/separation of the surface veneer. It is a hidden defect which cannot be detected by a simple inspection. At Sveza's plywood mills efforts to detect delamination include visual inspection and feeling of the plywood panel's edges. However it is not possible to detect delamination inside the panel. The defect is not visible neither to the naked eye, nor to a defect detector. The detector also fails to show the exact place of the defect.
Expected solution: We are looking for a process solution that could help: 1. Detect at least 95% of delamination defects during the process (on the run). It is important to remember that delamination is a hidden defect that cannot be detected by visual inspection. 2. Make the operator aware of the defect. The solution readiness level should be at least that of a working prototype.
Alternative ways of raw wood de-barking (birch, aspen)
Issue: The current technology provides for log de-barking by bark being cut off Circularly under pressure. The existing equipment do not ensure a 100 per cent de-barking due to the variability of the logs diameter and growth defects (knots, sweep, in-bark, cracks, butt swelling, etc.). The wood outer layers are damaged; and abrasive material consumption is higher due to sand and pebble getting onto the de-barked surfaces.
We are looking for an alternative solution for raw wood de-barking, that would exclude the mechanical impact onto the logs and remove soil and sand particles. Expected result: 1. 100 % de-barking. 2. Removal of foreign non-metal objects. 3. Increase of high graded veneer recovering due to the decreased amount of green veneer defects caused by de-barking (impurities, tooth marks). 4. Improvement of raw wood consumption rate.
Alternative technology of raw wood preparation / pre-conditioning without hydrothermal treatment and drying
Issue: To prepare raw wood for use it is subject to a hydrothermal treatment. Logs are preliminary soaked in hot water, and then conditioned to the required moisture content by drying. To condition the wood, the water pools need constant heating, regular maintenance and cleaning by using staff. The process results in producing wastewaters. The wood is dried in thermal-oil heated drying chambers. The exiting raw wood can have irregular moisture content and need to be re-dried. Both operations have low energy efficiency. The heat of the pools («steam over the water") and of the chambers is not re-used.
Expected solution: We are looking for an alternative technology, that would increase energy efficiency and wood preparation for use; and that would improve raw wood consumption rate as well.
Solutions to reduce the exploitable age of birch from 60 years to 30 and less
Issue: Sveza uses birch logs older than 60 years to manufacture products. This time is minimum required for a tree in natural conditions to achieve the necessary size and to get suitable for processing. Long growth period limits the amount of plots suitable for wood harvesting. Besides, wood quality under the natural growth conditions is lower due to the absence of good initial planting material and timely care.
Expected solution: We are looking for alternative variants of birch cultivation including breeding, modified, seedlings grown in vitro, cuttings, having the following parameters: 1. Growth period to felling age under 60 years (the shorter the better). 2. The wood quality should exceed that of naturally grown in North-West and Ural (diameter, sweep, decay, etc.). 3. The solution should comply with the forestry legislation of RF: meet the established standards for reforestation within the lands of the Russian forest fund (negotiable: on agricultural land).
Alternative means of cut wood removal from the forest during season of bad roads and off-road
Issue: To ensure stable supply of raw wood to the mills, Sveza develops its own wood harvesting in Leningrad, Vologda, Kostroma, Sverdlovsk, Tyumen and Perm regions. The main harvesting season is winter. The climatic conditions and lack of well-developed all-season road infrastructure in forest areas do not allow regular and stable access to the forest plots. Construction of new roads requires big investments and their use is possible not earlier than one year after the construction has begun. Additional information:
Forest areas are located in temperate regions, the temperature range - 35 °C to + 35 °C, lower winter temperatures are unstable with frequent thaw, annual precipitation 900 to 1200 mm, snow cover 1 to 1000 mm.
Mostly clay and loam soils with lower load-bearing capacity, wet, swampy in the forests of lower yield class. Rare: podzolic, sand and sub-sand. Soil freezing in winter (December to March): not more than 0.5 m.
Length of forest roads from felling areas to roadside landing / pavement varies from 1 km to 20 km with the average length of 7.9 km.
Expected solution: We are looking for alternative means of wood removal / construction of all-season forest roads. Requirements to the expected solution: 1. Transporting of over 300,000 m3/km of cargo annually by forest road is possible. 2. Transported cargo parameters: round wood with a diameter up to 60 cm, length 3 to 6 m, piled coefficient 0.5 – 0.65, weight of 1 m3 of wood – 700 to 900 kg. 3. Functions effectively in specified soil conditions regardless of weather factor and season. 4. Service life – over 10 years. 5. Meets the forestry legislation of RF, observes the established environmental standards.
Solution to equalize moisture throughout a veneer sheet
Issue: The production of plywood consists of the following stages: steaming of birch logs, debarking, and cutting into short sections. Then, the short logs are peeled to obtain a thin layer of wood (veneer). After peeling, the raw veneer should be dried to about 6-8% moisture content. Too high moisture content results in poor glue bond, and veneer delamination. With the currently available technology, it does not seem possible to obtain even moisture throughout a veneer sheet during drying. The problem is that some places of the veneer sheet have higher moisture content than the other, which negatively affects the quality of the final product. Expected solution: We are looking for a solution that uses microwave radiation for further drying of certain places of veneer sheets to achieve the required moisture content (6-8%). The microwave action should be applied only to the places of the sheet which have too much moisture and avoid places with the right moisture. Veneer sheets are 2,700 mm x 1,500 mm, and 3 mm thick. The solution should be at least a minimum viable product (MVP).