Reconstituted Wood Products Research Articles

Engineered wood products as substitutes in the Canadian building construction industry

Engineered and reconstituted wood products play an important role in building construction, and have positive environmental impacts. However, the wood products compete with other construction material (concrete and steel) in terms of prices in the Canadian building construction industry, and the price competition has not been explored in past literature. In order to promote the use of wood and wood-based products, there is a need to understand how prices influence the choice of construction material. We estimated the own and cross-price elasticities of demand of construction material in Canada using standard log-linear regression models with consumption and price data from 1990 to 2017. Our study shows that engineered and reconstituted wood products are substitutes for cement and steel, and hence there is a need to focus on the development of these value-added forest products, to create sustainable local economies that are economically viable, environmentally sound and socially responsible.

Characterization of Wood Filament in Additive Deposition to Study the Mechanical Behavior of Reconstituted Wood Products

The use of materials derived from biomass is unavoidable to decrease environmental impact of products. The main advantage of the Additive Manufacturing (AM) concept is the ability to create complex geometries one layer at a time. The primary aim of this study was to create objects using reconstituted wood through manufacturing with low environmental impact. Wood can be converted into various derivatives allowing the introduction of sustainable material into the product lifecycle. This work uses an AM device adapted to a Computer Numerical Control (CNC) machine [1] to produce a reconstituted wood product by filament deposition. The first part assessed the deposit of wood pulp with a 3D printing head device, while the second part focuses on the characterization of microscopic structure of the material. Fiber morphology and mechanical properties of composite materials incorporating the filaments are characterized.

Recycle, Bury, or Burn Wood Waste Biomass?: LCA Answer Depends on Carbon Accounting, Emissions Controls, Displaced Fuels, and Impact Costs

SummaryThis study extends existing life cycle assessment (LCA) literature by assessing seven environmental burdens and an overall monetized environmental score for eight recycle, bury, or burn options to manage clean wood wastes generated at construction and demolition activity sites. The study assesses direct environmental impacts along with substitution effects from displacing fossil fuels and managed forest wood sourcing activities. Follow‐on effects on forest carbon stocks, land use, and fuel markets are not assessed. Sensitivity analysis addresses landfill carbon storage and biodegradation rates, atmospheric emissions controls, displaced fuel types, and two alternative carbon accounting methods commonly used for waste management LCAs. Base‐case carbon accounting considers emissions and uptakes of all biogenic and fossil carbon compounds, including biogenic carbon dioxide. Base‐case results show that recycling options (recycling into reconstituted wood products or into wood pulp for papermaking) rank better than all burning or burying options for overall monetized score as well as for climate impacts, except that wood substitution for coal in industrial boilers is slightly better than recycling for the climate. Wood substitution for natural gas boiler fuel has the highest environmental impacts. Sensitivity analysis shows the overall monetized score rankings for recycling options to be robust except for the carbon accounting method, for which all options are highly sensitive. Under one of the alternative methods, wood substitution for coal boiler fuel and landfill options with high methane capture efficiency are the best for the overall score; recycling options are next to the worst. Under the other accounting alternative, wood substitution for coal and waste‐to‐energy are the best, followed by recycling options.

Analysis of electricity consumption: a study in the wood products industry

This paper evaluates the effect of industry segment, year, and US region on electricity consumption per employee, per dollar sales, and per square foot of plant area for wood products industries. Data was extracted from the Industrial Assessment Center (IAC) database and imported into MS Excel. The extracted dataset was examined for outliers and abnormalities with outliers outside the quantile range 0.5–99.5 dropped from the analysis. A logarithmic transformation was applied to eliminate the skewness of the original data distributions. Correlation measurements indicated a moderate association between the response variables; therefore, a multivariate analysis of variance test was performed to measure the impact of the three factors: industry type, year, and region, simultaneously on all response variables. The results indicated some effect associated with all three factors on the three measures of electricity consumption. Subsequently, univariate ANOVA tests were conducted to determine the levels of the factors that were different. Most levels of industry type were associated with significantly different energy consumption, an expected result since some of the industries are more energy intensive than others. The industries in Standard Industry Code (SIC) 2493 (reconstituted wood products) are the groups with the highest electricity consumption with means of 38,096.28 kWh/employee, 0.86 kWh/sales, and 154.14 kWh/plant area while industries grouped in SIC 2451 (mobile homes) have the smallest consumption with means of 6811.01 kWh/employee, 0.05 kWh/sales, and 9.45 kWh/plant area. Interestingly, differences in regional consumption were found to be linked to the proportion of industry types by region. Data analysis also indicated differences in electricity consumption per employee for the factor year, but for the other response variables, no differences were found. These main results indicate that industries in the wood products sector have different electricity consumption rates depending on the type of manufacturing processes they use. Therefore, industries in this sector can use these comparisons and metrics to benchmark their electricity consumption as well to understand better how electricity costs might vary depending on the region they are located.

Durability and microstructure analysis of CO2-cured cement-bonded wood particleboard

Dry-processed cement-based wood composites are reconstituted wood products with desirable longevity, fire resistance and life cycle cost. In this study, the effects of accelerated aging on the performance of CO2-cured cement-bonded wood particleboards were investigated. The accelerated aging conditions considered simulated natural aging phenomena. Repeated wetting–drying and freezing–thawing cycles led to increased stiffness and somewhat reduced toughness. X-ray diffraction and thermogravimetric analyses indicated that aging effects led to increased CaCO3 and decreased Ca(OH)2 contents in CO2-cured cementitious composites. Mercury intrusion porosimetry test results indicated that CO2 curing reduced the capillary pore volume in both unaged and aged boards.

Pemanfaatan Kayu Manis (Cinnamomun burmanii) Berdiameter Kecil untuk Balok I-joist sebagai Bahan Konstruksi (Utilization of Small-Diameter Cinammon Logs for I-joist Beam as Construction Material)

Wood-processing industries currently face the limitation of large-diameter wood logs, due to their scarce stocks from natural forests. Wood from plantation forests can deserve consideration as an alternative raw material for those industries. However, plantation-forest woods are usually of small-diameter sizes and lower qualities compared to those of natural forest woods. One solution to deal with those problems is the conversion of plantation-forest woods into the reconstituted wood products, which can be arranged to various desirable sizes, and more beneficial for construction and other purposes. Hereby, the manufacturing of reconstituted wood products, called I-joist beam was tried from small-diameter plantation forest wood species, i.e. cinnamon wood (Cinnamomum burmanii). The assembling used phenol-resorcinol-formaldehyde adhesive. Mechanical properties of the I-joist beam with vertical-gluing profiles between laminae in the web portion were lower than those of the corresponding small-sized defect-free solid wood, but higher than those of I-joist with horizontal-gluing profiles between laminae in the web as well as the horizontally laminated beam made-up of cinnamon wood-laminae. The angle between wood ray and gluing line (plane) correlated negatively with the strengths of I-joist beam. These results indicated the positive prospect of manufacturing I-joist beam from small-diameter cinnamon wood for construction material.

The role played by UNB in wood products innovation in Atlantic Canada

This paper provides an overview of the historical development of wood science instruction and research at the Faculty of Forestry and Environmental Management, University of New Brunswick, and the role played by the Wood Science and Technology Centre in enhancing the level of innovation in the wood industry in Atlantic Canada. A review of some of the wood product innovation needs for Atlantic Canada is also given. Key words: wood product innovation, wood science education, lumber scanning, wood modification, structural wood products, reconstituted wood products, wood durability, wood chemical products

Formaldehyde Exposure in U.S. Industries from OSHA Air Sampling Data

National occupational exposure databanks have been cited as sources of exposure data for exposure surveillance and exposure assessment for occupational epidemiology. Formaldehyde exposure data recorded in the U.S Integrated Management Information System (IMIS) between 1979 and 2001 were collected to elaborate a multi-industry retrospective picture of formaldehyde exposures and to identify exposure determinants. Due to the database design, only detected personal measurement results (n = 5228) were analyzed with linear mixed-effect models, which explained 29% of the total variance. Short-term measurement results were higher than time-weighted average (TWA) data and decreased 18% per year until 1987 (TWA data 5% per year) and 5% per year (TWA data 4% per year) after that. Exposure varied across industries with maximal estimated TWA geometric means (GM) for 2001 in the reconstituted wood products, structural wood members, and wood dimension and flooring industries (GM = 0.20 mg/m3. Highest short-term GMs estimated for 2001 were in the funeral service and crematory and reconstituted wood products industries (GM = 0.35 mg/m3. Exposure levels in IMIS were marginally higher during nonprogrammed inspections compared with programmed inspections. An increasing exterior temperature tended to cause a decrease in exposure levels for cold temperatures (−5% per 5°C for T < 15°C) but caused an increase in exposure levels for warm temperatures (+15% per 5°C for T >15°C). Concentrations measured during the same inspection were correlated and varied differently across industries and sample type (TWA, short term). Sensitivity analyses using TOBIT regression suggested that the average bias caused by excluding non-detects is approximately 30%, being potentially higher for short-term data if many non-detects were actually short-term measurements. Although limited by availability of relevant exposure determinants and potential selection biases in IMIS, these results provide useful insight on formaldehyde occupational exposure in the United States in the last two decades. The authors recommend that more information on exposure determinants be recorded in IMIS.

Carbon accounting model for forests in Australia

CAMFor (Carbon Accounting Model for Forests) is a sophisticated spreadsheet model developed to assist in carbon accounting and projection. This model can integrate information from a range of alternate sources including user input, default parameters and third party model outputs to calculate the carbon flows associated with a stand of trees and the wood products derived from harvests of that stand. Carbon is tracked in the following pools: • Biomass (stemwood, branches, bark, fine and coarse roots, leaves and twigs) • Soil (organic matter and inert charcoal) • Debris (coarse and fine litter, slash, below ground dead material) • Products (waste wood, sawn timber, paper, biofuel, reconstituted wood products) These pools can be tracked following thinning, fires and over multiple rotations. A sensitivity module has been developed to assist examination of the important assumptions and inputs. This paper reviews the functionality of CAMFor and reports on its use in a case study to explore the precision of estimates of carbon sequestration in a eucalypt plantation. Information on variability in unbiased models, measurement accuracy and other sources of error are combined in a sensitivity analysis to estimate the overall precision of sequestration estimates.

High-temperature wear of cemented tungsten carbide tools while machining particleboard and fiberboard

Published research on the wear processes of cemented tungsten carbide tools used for machining reconstituted wood products was reviewed, and the current state of knowledge in this area was evaluated. Underlying assumptions and conclusions regarding high-temperature oxidation/corrosion wear during machining were examined in view of known reaction kinetics of cemented tungsten carbide alloys in oxidative and corrosive environments at temperatures that may occur at the cutting edge. This examination indicated that some wear mechanisms other than high-temperature oxidation/corrosion are likely to be rate-controlling when machining reconstituted wood products such as particleboard and fiberboard.

ニュージーランド森林資源価値の最大活用

The forest industry in New Zealand continues to expand and it is forecast that the amount of forests available to harvest will increase substantially over next 30 years. Based on the forests already planted there will be an availavility of at least 30 million m3 of wood per annum by the year 2010. Depending on planting rates over the next 20 years the harvest could well increase to more than 50 million m3 from 2025 onwards. To achieve this level of harvest will require a planted forest estate in excess of 2.5 million hectares. By far the most predominant species is radiata pine which grows exceptionally well under New Zealand conditions. With forestry already accounting for 12.8% of New Zealand's total exports this additional wood supply represents a major opportunity for New Zealand to substantially increase its export earnings by maximising the value of this wood and fibre resource.Radiate pine is well suited to the manufacture of a wide range of solid wood, reconstituted wood products and pulp and paper products. Its value can also be significantly enhanced by taking advantage of the variability in wood and fibre types both within a single tree and between families and clones of the same species. This variation can be used to maximise product quality by selecting different parts of the tree or differrent radiata pine clones for a particular end use.

Wood adhesives based on tannin extracts from barks of some pine and spruce species

Barks available in commercial quantities in Australia and overseas have been examined for their efficacy as raw materials for conversion to high quality adhesives for reconstituted wood products. Previously bark from maturePinus radiata was found to be suitable. This paper examines the suitability of barks from four mature pine species (Pinus caribaea, Pinus elliottii, Pinus pinaster andPinus sylvestris), one young pine species (Pinus radiata) and one spruce species (Picea abies). Only the bark extracts ofPinus caribaea andPinus pinaster gave high quality (Type A bond, WBP) wood adhesives. The gluing properties of the adhesives derived from the extracts appeared to be dependent on their contents of formaldehyde-reactive polyflavanoids as indicated by their Stiasny values, with a value of 65% being the minimum for producing a high quality adhesive by the methods used.

Comparative response of reconstituted wood products to European and North American test methods for determining formaldehyde emissions

The European large-chamber, the North American large-chamber, the European perforator, and the North American desiccator test protocols for formaldehyde emissions from wood products were compared. Two formaldehyde analytical techniques using chromotropic acid and pararosaniline chemistry were used for the large-chamber testing. Six sample sets, chosen for their range in formaldehyde emissions, provided the experimental data. The sets consisted of five particleboards and one medium-density fiberboard (MDF). The European large-chamber protocol produced values that were 20% lower than the North American large-chamber protocol and both analytical techniques produced similar test results. Linear relationships between all the tests were strong. These relationships should allow manufacturers on both continents a level of confidence in predicting their conformance with formaldehyde emission standards. These tests confirm a similarity seen by others in the emission rates of North American and European products.

Potentialities of short-rotation forestry for developing countries

An old forest management system holds new promise for meeting the fuel, food, and fibre demands of bourgeoning humanity. Intensively practised coppice forestry adapted to local conditions, can be an important source notably of fuelwood but also of raw material for reconstituted wood products and a possible source of other fuels such as alcohol or gas.

Hydroxy Propylated Lignin-Isocyanate Combinations as Bonding Agents for Wood and Cellulosic Fibers

Abstract Lignin and hydroxy propylated lignin derivatives were reacted with diisocyanates in the presence of cellulose fibers and wood particles. The attachment of lignin and lignin derivates to hydroxyl-rich surfaces of lignocellulosic materials proved to be a convenient way for increasing strength properties of reconstituted fiber and particle materials. Results indicate that hydroxypropylated lignin derivatives are capable of contributing equal or even greater strength increases to relignified fiber composites than do monomeric or polymeric diisocyanates alone. With reinforced fiber mats, it was found that strength properties were virtually unaffected up to a level of approximately 50% replacement of diisocyanates by lignin-based materials. This beneficial contribution by lignin to bonding properties could not be verified for reconstituted wood products, the strength and swelling properties of which suffered in relation to lignin content. Thftse differences are explained with differences in method of a...

Modern Trends and New Timber Products in the Timber Industry

There is a trend throughout the world not only to look for new uses for wood as it is, there is a large variety ranging through houses, furniture, toys, rayon and alcohol but to reduce the costs and to improve the reliability of already known products and to develop new, more economical processes. To attempt to cover the field in a single lecture woulfd be an impossible task, so I shall limit my talk tjo some selected developments and products, with particular reference to current and future forest product utilization in South Africa and to those products of wood which concern you as teachers and instructors lin woodwork. If, as trends indicate, wood will become a scarce resource by the turn of the century, efforts directed towards growing more wood are important, but efforts to utilize existing wood much more completely are of even higher priority. The aim of forest products research is to maximise the usefulness of wood from tree to final product, and, in this era of shortages, pollution and environment control, to recycle such products. When talking about modern or new trends in industry, the influence of tradition must be taken into account, for what may be considered a modern trend in South Africa may be of long standing in another country and vice versa. For example, timber housing is a traditional building method in many countries outside South Africa but its general acceptance by the local building authorities could well be classified as a modern trend, if not a break-through, for it would open the market to a variety of wood-based products which would have a tremendous influence on both the construction and the forest products industries. Greater mechanization is evident in all sectors of the industry, whether it be tree-shears for felling, harvesting and handling equipment, mechanical debarkers, or the many hundreds of pushbutton or electronically controlled operations to be seen in any modern sawmill, plywood factory, chipboard plant, etc. Wood is used at present mainly in solid form, either in the round (as in poles, posts and piling) or as sawn timber (lumber) whether rough or planed (as in construction, packaging, railway sleepers, furniture, etc.). Solid wood is being increasingly used in new forms, as in laminated wood structures, or it is being replaced by reconstituted wood products in which the woody material is reduced to smaller elements and then re-assembled to provide a wood-based product, very often with built-in properties which make it superior to solid wood for many uses. Glue-lamination, together with end-jointing techniques such as finger-jointing, has made possible sections and lengths and shapes not to be had in natural sawn lumber.