Treesearch

This article documents cradle-to-gate life-cycle inventories for softwood lumber, hardwood lumber, and solid-strip hardwood flooring manufacturing from the Inland Northwest and the Northeast–North Central regions of the US. Environmental impacts were measured based on emissions to air and water, solid waste, energy consumption, and resource use. The manufacturing stage consumed the greatest amount of energy representing 90 – 92% of the total. Total energy consumption for softwood lumber manufacturing was about one-half of that required for hardwood lumber and hardwood flooring. The use of...

Finding the environmental impact of building materials is becoming increasingly more important because of public environmental awareness. Accurate and precise life-cycle inventory data on wood products are needed to meet this demand. This study examined softwood lumber manufacturing in the northeastern and north central US using life-cycle inventory methods. Material flow, energy type, and energy use were identified for these sawmills. A softwood log mass conversion of 42.1% to planed dry lumber was found. Values of 355 MJ of electricity and 2730 MJ of processed energy per cubic meter were...

The discussion in this chapter is concerned with moisture content determination, recommended moisture content values, drying methods, methods of calculating dimensional changes, design factors affecting such changes in structures, and moisture content control during transit, storage, and construction. Data on green moisture content, fiber saturation point, shrinkage, and equilibrium moisture content are given with information on other physical properties in Chapter 4.

A resource assessment and biorefinery siting optimization model was developed and implemented to assess potential biofuel supply across the Western United States from agricultural, forest, urban, and energy crop biomass. Spatial information including feedstock resources, existing and potential refinery locations and a transportation network model is provided to a mixed integer-linear optimization model that determines the optimal locations, technology types and sizes of biorefineries to satisfy a maximum profit objective function applied across the biofuel supply and demand chain from site...

Low-rise nonresidential building construction is an important market for lumber, structural wood panels, nonstructural wood panels, and engineered wood products in the United States. This report examines low-rise nonresidential buildings of four or fewer stories only. Buildings with five or more stories are normally severely restricted by building code from being wood framed. In 2008, 1,758 million board feet of lumber, 56 million board feet of glulam timber, 2,677 million square feet, 3/8-in. basis, of structural panels, 79 million square feet, 3/8-in. basis of constructural panels, 68...

Sustainability issues about wood fuels are increasingly being debated, but the European Union has decided not to impose EU-wide sustainability criteria for solid biomass. United Kingdom energy companies plan massive increases in their utilization of wood energy, further fuelling European demand for wood energy. In order to increase control of the value chain, European energy companies are investing in large-scale wood pellet production facilities, particularly in North America. Wood energy use and pellet production levels are increasing in the Russian Federation, despite the overall...

Paper and paperboard consumption declined sharply in 2009 by 9% in Europe and 10% in the United States relative to 2008; just a fraction of that decline was recovered by early 2010. Pulp and paper commodity prices fell in 2009, dropping well below 2008 price levels, but prices began to stabilize by mid-year, and in some cases fully recovered by early 2010. A wave of capacity withdrawals in the form of mill downtime and shutdowns helped stabilize the market balance between product supply and demand. Pulp prices were boosted also by shutdowns of Chilean pulp capacity due to the devastating...

Industrial timber use has provided timber revenue that has helped make timber supply and demand more sustainable in the leading timber producing regions of the world. Sustainable development implies not consuming more resources today than we can replace tomorrow, but sustainable forest management implies more than merely a non-declining supply of timber. Forests as a whole provide vital ecosystem services, as important atmospheric carbon sinks for example. According to the Intergovernmental Panel on Climate Change, global deforestation is a major contributor to global atmospheric carbon...

We identify confusion in the literature about the definition and calculation of repetitive member factors. This confusion casts some doubt on the validity of the 1.15 repetitive member factor permitted in ASTM D 245 and ASTM D 1990.

In this paper we raise three technical concerns about Evans’s 1999 Appita Journal “variance approach” to estimating microfibril angle. The first concern is associated with the approximation of the variance of an X-ray intensity half-profile by a function of the microfibril angle and the natural variability of the microfibril angle, S2 ≈ μ2/2 + σ2. The second concern is associated with the approximation of the natural variability of the microfibril angle by a function of the microfibril angle, σ2 ≈ f(μ). The third concern is associated with the fact that the variance approach was not...