PARTICLEBOARD MADE WITH CROP RESIDUES MIXED WITH WOOD FROM PINUS RADIATA

Author

Rose Marie Garay,*a Francisco MacDonald,a María Luisa Acevedo,b Beatriz
Calderón,b and Jaime E. Araya c

The incorporation of crop residues was studied in particleboard panels (agrifibers, AG) in mixture with wood from Pinus radiata D. Don. Four crop residue stubble types were used, wheat, corn, rice plants, and rice husk. Their densities were compared. A wide array of mixtures varying from 9:1 = wood:AG to 1:9 = AG:wood were used to make the boards, from which the fundamental physical and mechanical properties were determined, to select one with the best properties and use potential. All AG were suited for board panels, although wheat and corn stubble gave better results, and their low fibre content was easily incorporated in low proportions without major modifications of processes and products.

Keywords: Agrifibers; Agricultural residues; Particleboard; Radiata pine; Corn; Rice husk; Wheat
Contact information: a: University of Chile, Forest Science Faculty, Department Wood Engineering, Box 9206, Santiago, Chile. b: University Autonomy of Chapingo, Forest Science Division, Industrial Forest Engineering, México. c: University of Chile, Sciences Agricultural Faculty, Department of Healthy Vegetable, Box 1004, Santiago, Chile. * Corresponding author: rgaray@uchile.cl

INTRODUCTION
In Chile, as throughout the world, the panel industry has grown continuously in recent years, using mainly wood produced on plantations. The most important Chilean company producing particleboards (over 90% of national production) has adopted the ISO 14001 certification, to produce boards only from industry byproducts such as radiata pine sawdust, shavings, and chips, instead of logged trees (MASISA 2008). So, this industry currently uses byproducts derived from other industrial processes, and competes to an increasing degree to access these resources at competitive prices. Such practices allow them to achieve good profitabilities in their business (Garay 2006).

In agriculture there is interest in the use of agrifibres (AGs), and in substantially increasing the land area under production. Actually some AGs and residues from production process are being used in cattle food, such as rice husk, and residues of wheat and corn plants. This scenario represents a use opportunity for logging, as represented by products such as sawdust, shavings, and chips, among others that surely will be incorporated. These prime products are in demand also by the cellulose industry, and their importance will increase gradually as an energy resource for the same industries, and for developing biofuels (Wood 2002; Garay 2006; Martinez 2006).

Alternative AGs are a poorly used resource to make products having aggregated value. This happens because there is little knowledge on their industrial use. The fabrication of boards with AG makes it possible to incorporate carbon capture and storage in these products, instead of liberating this carbon to the environment when burning these residues. The emissions of CO2 to the atmosphere that are produced to obtain biomass, as they proceed from a carbon withdrawn from the atmosphere in the same biological cycle, do not affect the equilibrium of the atmospheric carbon, and thus they do not increase the greenhouse effect. And in cases where they substitute for fossil fuels, the use of AGs contributes to reduced net emissions of CO2 to the air (Martinez 2006).

AG boards must compete in the market with traditional boards of wood materials. The physical and mechanical parameters of a standard board made in Chile, which are specified at various thicknesses, are presented in Table 1.

Table 1. Chilean Particle Board Properties

Thickness Flexural strength (mm) (N/mm2)
9 16
12 16
15 15
18 15
24 15
32 13 Source: REGISTER CDT (2007).

Internal bond strength (N/mm2)
0.50 0.50 0.50 0.50 0.45 0.40

Thickness swelling 24 h (%)

Density (Kg/m3)

Growers throughout the world are often challenged annually to eliminate harvest residues from their farms, and they strive to do so without creating environmental problems or unnecessary costs. To burn stubble is a questionable practice in many areas, as it often damages the soil and the environment, and it may have an adverse effect on health (Manterola et al. 1999).

Although typically the residues from wheat and barley crops, rice husk, and others have little or no value, they may become prime raw materials for the board industry, with the comparative advantage of a lesser cost than that of wooden fibres (Pease 1998). Today, logging volumes are reduced, and there is a decreasing availability of wood (FAO 2001), but crop residues are renewed each year, often in sustainable volumes sufficient to provide for the production of boards (INE 2006). The area of land cultivated in the Bio- Bio region in Chile, which concentrates most of the Chilean forestry industries, is presented in Table 2.

Table 2. Surface Cultivated (ha) with Agricultural Crops in the VIII Region of Chile

Max. 25 700 Max. 25 660 Max. 25 640 Max. 25 630 Max. 25 600 Max. 25 570

Agricultural year
2000/2001 2001/2002 2002/2003 2003/2004 2004/2005 2005/2006
Source: INE (2006)

Wheat Corn Rice
111,600 3,730 4,460 113,330 4,350 4,340 108,250 5,180 4,560 114,100 6,600 3,800 115,200 7,100 3,790
90,070 5,440 4,580

Total
184,290 183,640 176,790 189,430 187,360 166,160

Garay et al. (2009). “Crop residue use in particleboard,” BioResources 4(4), 1396-1408. 1397 

For further details log on website :
https://www.ncsu.edu/bioresources/BioRes_04/BioRes_04_4_1396_Garay_MACA_Particlebd_Crop_Residues_Pine_585.pdf