Your search resulted in 248 documents. Displaying 25 entries per page.
New developments in wood preservation
1974 - IRG/WP 335
Most of the developments in wood preservation in recent years have been stimulated by changing circumstances, particularly the increasing interest in reducing hazards and environmental, pollution but also the serious difficulties that are now being encountered in obtaining economic supplies of established preservatives. There is perhaps a danger that new controls to reduce pollution dangers may be...
B A Richardson
Technique for monitoring absorption during a vacuum pressure process
1992 - IRG/WP 92-3696
A laboratory technique was developed and an apparatus constructed which allowed for the direct and continuous measurement and observation of volumetric uptake of water-borne preservative into wood samples throughout a controlled vacuum-pressure treatment process. Fractional filling of void space was calculated. Graphing (fractional saturation) against time allows prediction of optimum cycle length...
A J Pendlebury, J A Petty
Improvement of liquid penetration of wood by precompression under appropriate conditions and recovery process
1993 - IRG/WP 93-40014
A new system for enhancing the penetration of liquid into wood using a precompression treatment was designed, and the effects of compressive deformation and recovery on liquid uptake were evaluated. Precompression of up to 60% under appropriate moisture and heat conditions effectively increased the penetration of liquid into refractory wood samples of practical sizes without producing any strength...
I Iida, Y Imamura
Bending properties of TCMTB-treated Southern pine sapwood using supercritical carbon dioxide impregnation process
1997 - IRG/WP 97-40080
The effects of elevated pressure and treatment with thiocyanomethylthiobenzothiazole (TCMTB) on the bending properties of Southern pine sapwood were evaluated at pressures ranging from 1,800 to 3,600 psi. All bending properties were affected to some extent by supercritical fluid treatment. Modulus of elasticity and work to maximum load were not significantly affected by pressure levels. Modulus of...
Gyu-Hyeok Kim, S Kumar, E S Demessie, K L Levien, J J Morrell
A study on the pressure impregnation of Eucalyptus globulus fence posts with CCA preservatives. Part 1
1988 - IRG/WP 3470
This paper describes the impregnation with CCA preservatives by full-cell process of Eucalyptus globulus fence-posts. Several treatments were made for different times of initial vacuum and treating pressure, with fence-posts from two coppice plantations (1st and 2nd rotations), assembled into three diameter classes: small, medium, large. The results concerning the absorption and lateral penetratio...
D De Sousa Castro Reimão, L Nunes
Selective chromate elimination from the storage-drainage-water of a wood impregnation plant
1980 - IRG/WP 3153
With the Enviro-Chrom-Ex process it is possible to eliminate ecologically and economically hexavalent chromium (chromate) from water selectively. The process which is based on the principle of selective ion exchange works with different chromate concentrations and under the presence of other ions, irrespective of the water hardness. The values of water-offtake reach 0.1 mg CrVI at maximum, causing...
O Wälchli, R Ott, R Hugener, E Graf, B Lieberherr
A study on the pressure impregnation of Eucalyptus globulus fence-posts with CCA preservatives. Part 2
1989 - IRG/WP 3514
This paper describes the second part of a study on pressure impregnation of Eucalyptus globulus fence-posts with CCA preservatives presented at the IRG 19th Meeting. Fence-posts of three diameter classes, were treated, considering only one treatment schedule. The results show possibility of vacuum-pressure impregnation of blue gum fence-posts, with diameter less than 9 cm, though mainly by longitu...
L Nunes, D De Sousa Castro Reimão
Temperature and pressure inside wood during creosote impregnation
1991 - IRG/WP 3649
Creosote gives the best protection against decay for sleepers and poles. However, it has a major drawback - bleeding. Modified impregnation processes to reduce bleeding have been tried. For developing such processes it is important to know the actual temperature and pressure inside the wood. This paper describes measurement of temperature and pressure inside wood during creosote impregnation. The ...
Ö Bergman
Controlled envelope treatments of Pinus sapwood, achieved by modifications to impregnation process and carrier solvents
2003 - IRG/WP 03-40258
Specimens of slash pine or radiata pine were treated to a target retention of 0.02% m/m permethrin with conventional light organic solvent fluids or with oil-modified fluids (Tanalith® T). Best achievable envelopes from LOSP fluids were poorly controlled, penetrating not only the target outer 0-5 mm zone (mean 0.019%, RSD 28%), but also breaking through into the 5-10 mm zone (mean 0.013%, RSD 37%...
M J Kennedy, P R S Cobham
Estimation of the impregnation degree of pine wood by the distribution analysis of active ions concentration in the cross-section
1999 - IRG/WP 99-20174
Samples in the form of pine wood rollers of diversified moisture content of ca. 50, 28 and 12% were impregnated with a water solution of the mixture type CCB with the use of the full-cell process. Moisture content was determined in individual layers from the girth to the pith. In the same way the concentrations of copper and chromium ions with the use of the spectrophotometric method and recalcula...
K Lutomski, B Mazela
Comparison of the anti-fungal efficacy of Cobra with drill perforation on oscillating pressure treated spruce transmission poles -Laboratory test
1988 - IRG/WP 3469
A laboratory method for measuring the depth of penetration of the fungicidal concentrations effective against basidiomycetes (brown rot) was developed. The tests on CCB oscillating pressure treated spruce transmission poles have shown that the depth of salt penetration can be increased by about 10 mm by a drill perforation before the impregnation. An even better penetration is reached, however, if...
E Graf, B Zgraggen
Microdistribution of water-borne preservatives in blue gum treated by full-cell process
1990 - IRG/WP 3617
The present work deals with the study of the microdistribution of copper, chrome and arsenic elements in Eucalyptus globulus Labill. sapwood, treated with a CCA water-borne preservative by full-cell process, with the help of scanning electron microscopy together with energy dispersion X-ray analysis technique. The work shows that the retention of CCA elements is high in vessels and vasicentric par...
D De Sousa Castro Reimão, J M Palacios
Gaseous preservative treatment of wood
1990 - IRG/WP 3631
A recent development in processing wood with a gaseous preservative means that dry, treated wood can be produced in under 30 hours with the benefits of product diversification, faster stock turnover and the ability to respond to short term demand. About 400,000 m³ of wood are treated each year in New Zealand with boron salts to protect from borer infestation. Traditionally this treatment is effec...
R Burton, A J Bergervoet, K Nasheri, P Vinden, D R Page
The susceptibility to sludging of sulfate and oxide CCA
1990 - IRG/WP 3599
Radiata pine sapwood was treated separately with a sulphate CCA-C and an oxide CCA in a pilot scale pressure plant using a full cell process. CCA solutions were recovered from the final vacuum phase, placed in plastic tubes, and their susceptibility to sludging determined by examining changes in solution pH, time required for sludge to form and weight and chemical composition of sludge formed. Sul...
B T Mutandadzi, P D Evans
Wood furfurylation process development. Part 2: Lowry impregnation trials
2007 - IRG/WP 07-40377
The objective was to evaluate whether Lowry-impregnation of Scots pine with FA100-mix, instead of the FA40-mix, would lead to similar or slightly higher WPGs and to investigate any potential changes in penetration pattern. The results indicate that the penetration was better, also penetrating the outer zone of the heartwood. Furthermore, it was possible to reduce the WPG-levels for pine down to 50...
M Westin, E Larnøy, S Lande
Impregnación de durmientes de quebracho blanco (Aspidosperma quebracho blanco) con preservadores cromocuproarsenicales (CCA)
2008 - IRG/WP 08-40428
CCA impregnation of railroad ties is a recent process in Argentina which has not been optimized in a commercial scale. This study analyzed the influence of treatment pressure on final retentions to optimize the impregnation process. Results showed that a 3.2% m/v solution resulted in 10.8 kg/m3 CCA retention. At 1187 kPa (12 kgf/cm2) quebracho blanco wood had an average absorption of 338 l/m3. Als...
D Gherscovic, Z Cataldi, J M Languasco
Effects of nano-wollastonite impregnation on fire resistance and dimensional stability of Poplar wood
2012 - IRG/WP 12-40595
The fire-retardant properties of Nano-Wollastonite (NW) in poplar wood (Populus nigra) were determined in this study. Some physical properties such as water absorption, volumetric swelling and Anti-Swelling Efficiency (ASE) were also measured. Specimens were prepared according to the ISO 11925 standard for the fire-retarding properties, and ASTM D4446-2002 standard for the physical properties. Imp...
A Karimi, A Haghighi Poshtir, H Reza Taghiyari, Y Hamzeh, A Akbar Enayati
Danish wood preservatives approval system with special focus on assessment of the environmental risks associated with industrial wood preservatives
2001 - IRG/WP 01-50166-01
The following is a description of the procedure used by the Danish Environmental Protection Agency to assess the environmental risks associated with preservatives used in the pressure impregnation of wood. The risk assessment covers issues considered to be of significance for the environment and which are adequately documented so as to allow an assessment. Such issues are persistence and mobility ...
J Larsen
Pinus and Eucalyptus fenceposts treated with creosote and solvex tar by hot and cold open-tank process
1987 - IRG/WP 3455
A comparative study of the behaviour of two different wood preservatives, creosote and solvex-tar, was made, using two wood species, Pinus pinaster Ait and Eucalyptus globulus Labill, by the hot and cold open-tank process. Results showed that the creosote behaved better in relation with the uniformity of its distribution in wood. On the other hand, better results were obtained on Pinus for both pr...
M V Baonza Merino
Comparison of cubic and plug samples for preparation and data assembly in permeability study
2000 - IRG/WP 00-20197
In order to determine if plug experimental samples (PES: 30 x 15 mm2 diameter) could be used for inspection of wood permeability characteristics, radial and longitudinal flow directions were prepared according to either PES or cubic experimental samples (CES: 100 x 20 x 20 mm3) from the sapwood zone of Sitka spruce and treated by tanalith-C according to full-cell process. Results from the two prep...
I Usta
New technique to analyze impregnation processes
1988 - IRG/WP 2304
Equipment has been developed to measure liquid flow in wood during impregnation processes. Basic principles of flow measurements using directly heated negative temperature coefficient thermistors, and some characteristics of the hardware developed are presented in this paper....
J P Hösli
The use of pressure cycling to improve heartwood penetration in Pinus radiata (D. Don)
1995 - IRG/WP 95-40050
This study investigates the effect of cycling pressure on the treatability of radiata pine heartwood. The results indicate that liquid penetration into the heartwood is affected by the preconditioning method used and pressure treatment time. There is no significant improvement in the penetration of Pinus radiata (D. Don) heartwood when a cycling or pulsation process is used....
P R S Cobham, P Vinden
Wood furfurylation process and properties of furfurylated wood
2004 - IRG/WP 04-40289
The first processes for “furfurylation” of wood (wood modification with furfuryl alcohol) were developed several decades ago. Furfuryl alcohol is a renewable chemical since it is derived from furfural, which is produced from hydrolysed biomass waste. Over the last decade modernised processes for furfurylation of wood have been developed. These new processes are based on new catalytic systems a...
M Westin, S Lande, M Schneider
Improved equipment and technique for high pressure sap displacement impregnation of natural round wood
1972 - IRG/WP 309
Hitherto the main problem in the practical application of high pressure sap displacement impregnation (HPSD) has been in devising a satisfactory cap. Such a cap must be easily fitted to different size log ends to give a leak proof seal. The present contribution describes a new type of cap and sealing system designed to meet these requirements....
C G W Mason, F B Shorland
Radical changes in the requirements for more safe pressure impregnation in the Nordic countries in 1988
1990 - IRG/WP 3581
After introduction of quality control schemes and standards in the Nordic countries during the seventies, the first radical change of the standards and practice of work took place after pressure from the labor unions and authorities in 1988 and 1989 in Denmark and in Sweden. A new class of preservation with less retention for out of ground contact use was introduced, fixation times were prolonged ...
B Moldrup