Treesearch

Shrub willow (Salix spp.) is an emerging lignocellulosic biomass utilized in fuel pellets as an energy source. However, improvements are needed to increase the efficacy of pellets in areas such as the energy content, durability, and hazardous carbon monoxide emissions. This study examined the effect of utilizing lignin as an additive on willow pellet properties. Two types of lignin were used in individual treatments: lignin recovered from the hot water extraction of willow (RecL) and commercial softwood kraft lignin (ComL). A statistical analysis of the ash content, energy content, bulk...

Predictions as to the quantity of lignocellulosic biomass (LCB) available vary considerably. Estimates range from at least 4 billion to as much as 170 billion metric tons per year worldwide (Klass, 1998; Rowell, 2007). Estimates of total quantity of woody biomass available range from at least 1.75 to 75 billion metric tons per year worldwide ( ~43% of total LCB) (Klass, 1998; Rowell, 2007). In the US, the forest-based biomass supply physically available in 2011 was estimated to be ~45 million dry tonnes per year depending on market economics with a feasible increase to as much as 225...

Woody biomass as a renewable resource for chemicals, materials, and energy has garnered significant attention to replace fossil-carbon sources. However, in carbohydrate-based biorefineries, the recalcitrance of wood warrants a pretreatment prior to further processing by enzymatic hydrolysis (EH) and fermentation. Various processes or a combination thereof, including but not limited to, low pH (mild and strong acid pretreatments), neutral pH (autohydrolysis includes hydrothermal and steam explosion pretreatments), high pH (mild and strong alkali pretreatments), organic solvents, ionic...

Mass timber buildings are increasing in popularity as the building industry aims to use more sustainable construction materials. A lateral force resisting system with a mass timber frame and a timber buckling restrained brace (TBRB) is presented as a possible solution to allow the expanded use of mass timber in buildings located in cities with high risk of natural hazards such as earthquakes and hurricanes. A series of nine quasi-static cyclic tests was completed to study the performance of the TBRB frame as well as the elastic performance of the bare mass timber frame. The variables...

The 3rd North American Mass Timber Research Needs Assessment Workshop sponsored by the US Forest Service, Forest Products Laboratory was held September 20-22, 2022. The purpose of the workshop was to convene experts on mass timber and cross laminated timber to develop a prioritized list of research needs for the North American mass timber industry. Invited workshop participants included design professionals, academics, industry leaders, and government employees. The workshop built upon prior mass timber research needs workshops that were conducted in 2015 and 2018.

This study conducted a cradle-to-grave life-cycle assessment (LCA) of engineered wood flooring manufactured in the eastern United States. System boundaries in this study included the following information modules: raw material extraction (A1), raw material transportation (A2), product manufacturing (and packaging) (A3), product transportation (A4), installation (A5), product use (B1-B7), and end-of-life (C1-C4). Two disposal options were considered for flooring products at the end of useful life: landfilling and burning. The burning option captures heat, which displaces use of natural gas....

This study conducted a cradle-to-grave life-cycle assessment (LCA) of solid hardwood flooring manufactured in the eastern United States. System boundaries in this study included the following information modules: raw material extraction (A1), raw material transportation (A2), product manufacturing (A3), product transportation (A4), installation (A5), product use (B1-B7), and end-of-life (C1-C4). Two disposal options were considered, landfilling and burning. The burning option captures heat, which displaces natural gas (D stage). A functional unit of 1 m2 of flooring with a weighted average...

Of the many observations reported in cellulose literature, the phenomena of “cocrystallization” and “moisture-induced shift in XRD” (XRD-shift) need re-examination. Does cocrystallization really occur or, entirely, something else is going on? Recent research carried out by the authors suggests that upon hydrothermal treatment of wood-cellulose, where cocrystallization has been reported to be occurring, the cellulose becomes partly crystalline from the pre-existing non-crystalline arrangement.(1, 2). Similarly, although the XRD-shift of wood’s (200) diffraction plane is real, based on the...

The native state of wood-cellulose has proven to be difficult to explore. Contrary to the traditional acceptance of wood-cellulose being crystalline, in 2016, the authors' research reported that the cellulose was not crystalline.[1] New evidence, presented here, further supports the non-crystalline model. This evidence consisted of 64% H2SO4 hydrolysis of tension- and opposite-aspen woods (TW and OW, respectively), anatomical examination of the TW- and OW-woods, presence and absence of the 93 cm-1 Raman band, respectively, in TW G-Iayer and TW S2 layer, and Raman spectra of TW-CNCs, wood...

The use of cross-laminated timber (CLT) has gained popularity during the past decade in North America, with many advances stemming from completed research and construction projects located in other countries. In particular, CLT has been utilized in vertical construction projects where many of its inherent features have been maximized. Despite these advances, the use of CLT in bridge structures has been limited and CLT has not been adopted into governing bridge design codes. This paper reports the results and conclusions of the laboratory investigation of the feasibility of CLT as a primary...