Your search resulted in 338 documents. Displaying 25 entries per page.
Variation in biological performance of CCA caised by preservative application method
1996 - IRG/WP 96-40072
A series of laboratory studies to investigate the influence of treatment application method on CCA performance in Cosican pine has been completed. Biological decay tests, such as serial exposures, were used to induce decay in wood at preservative retentions of up to 10 kg/m³ CCA salts. Significant differences in performance of the preservative against either brown, white or soft rot decay fungi were found depending upon the preservative application method used. The full-cell process gave the greatest level of CCA performance against Coniophora puteana whereas the Lowry empty-cell process gave the best performance against Coriolus versicolor and soft rot fungi. Pre-treatment steaming caused a general reduction in preservative efficacy. Analysis of the treated wood using FT-IR spectroscopy and electron microscopy with EDS for preservative micro-distribution indicated modification of the wood cell wall by steaming and differential distribution of copper depending on preservative application method. A hypothesis is proposed to account for the observed differences in preservative performance with treatment method.
P R Newman, R J Murphy
Comparative study between full cell and passive impregnation method of wood preservation for laser incised Douglas-fir lumber
2007 - IRG/WP 07-40359
Many wood species are highly resistant to conventional pressure treatment. To improve the chemical impregnation into Douglas-fir (Pseudotsuga menziesii Franco) lumber, the passive impregnation method had been developed. In this study, ability of the passive impregnation for lumber was compared with a conventional full cell method. Square Douglas-fir lumber with the incising density of 10,000 holes/m2 done by CO2 laser was treated by both passive impregnation and full cell method for the same treating time. Different incising densities were also used in passive impregnation to find out the optimum incising density. It was observed that there was no significant difference between these two methods for absorption of liquid, moisture content after dipping and the penetrated area both at cross and longitudinal section though the value was higher in case of full cell method. In case of different incising densities, absorption and penetration of liquid was similar for 10,000 holes/m2 and 7,500 holes/m2 but it was quite low for 5,000 holes/m2. Therefore, it can be concluded that incising density of 7,500 holes/m2 is optimum for passive impregnation. The absorption of liquid and its distribution in wood indicates that this non-pressure passive impregnation method can be a good preservative method for impermeable lumber and can be an alternative to full cell method.
Md N Islam, K Ando, H Yamauchi, Y Kobayashi, N Hattori
Comparison of permeability at different levels of moisture content in Bornmullerian fir (Abies bornmulleriana Mattf.) and Eastern spruce (Picea orientalis L.) impregnated under vacuum/pressure through full-cell method by using CCA and CCB of different concentrations
2007 - IRG/WP 07-40366
In this study, a comparison has been made in terms of the combined, longitudinal, tangential, and radial permeability of the species of Bornmullerian fir (Abies bornmulleriana Mattf.) and Eastern spruce (Picea orientalis L.) with moisture contents of 50 % and 15 %, which were impregnated under vacuum/pressure through full-cell method by using water-borne wood preservatives (impregnation materials) of Tanalith-C (CCA : copper-chromium-arsenic) and Wolmanit-CB (CCB: copper-chromium-boron) in concentrations of 2.5 % and 3.0 %. The experimental data obtained were examined in terms of the wood species concerned, level of moisture, type of the impregnation material used, concentration of the solution and the direction of the liquid flow, by taking as basis the level of absorption of the two different impregnation materials by the cell cavities of the wood species tested. Results of the tests made by using the impregnation materials of CCA and CCB in different concentrations (2.5 % and 3.0 %) have shown that the level of absorption (in the species of Bornmullerian fir and Eastern spruce) was the highest when the wood was dry (with a moisture of 15 %); and that when the wood was wet (with a moisture of 50 %), absorption of the wood preservative liquid was the highest in both of the species particularly when CCB is used. The results of this study have also revealed that the level of absorption of the impregnation material under all the experimental conditions was higher in the wood of Bornmullerian fir, compared to that of the Eastern spruce. The analyses made by using different concentrations of the impregnation materials have shown that in general, the impregnation materials of lower concentrations were absorbed relatively better by the wood, based on the direction of the liquid flow. In order to see the level of absorption of the impregnation materials, the amounts of liquid flow in different anatomic directions were compared in both species, and it was seen that under all the experimental conditions, the decreasing order of absorption according to direction was: combined>longitudinal>tangential>radial.
Chapter 11 - Preservation of talla bamboo
2007 - IRG/WP 07-10635-11
Researches revealed that the talla bamboo (Bambusa tulda Roxb.)) in Bangladesh could be full-cell pressure treated with CCA in green and dry conditions. The dry bamboo gives higher loading absorptions than green one when impregnated at same treating conditions. Also higher absorptions are obtained at nodes rather than internodes. Adequate penetration and retention results for ground and water contact uses are only possible by treating bamboos pre-dried to 10-15% MC. The green bamboo is easily treatable for indoor and overhead outdoor uses. The service life of this socio-economically important bamboo can easily be increased at least two times than nominal by CCA treating either green or dry bamboo. Two small holes made before pressure treatment in each internode will give split-free bamboo.
A K Lahiry
Chapter 12 - Treatment Groups of Bamboo
2007 - IRG/WP 07-10635-12
Study on distribution of CCA in three major bamboo species in Bangladesh, full-cell pressure treated at green and dry conditions revealed two treatment groups and some treating principles. Higher adequate treatment for ground and water contact use is only possible by treating problematic bamboo species pre-kiln dried up to half of its FSP and non-problematic species pre-dried up to FSP (20% MC). The non-problematic species can be treated in green conditions for indoor and overhead outdoor uses. Two smallest holes made before treatment in each internode will give split-free bamboo.
A K Lahiry
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 preparation techniques agreed in the test to determine the mean percentage of void volume filled by liquid both radially and longitudinally, while the preparation process (i.e. machining, sealing, etc.) of the experimental samples and the period of the data collection was quite longer in CES than that for PES in either flow direction.
An effective preservative treatment of borak bamboo (Bambusa balcoona Roxb.)
1996 - IRG/WP 96-40070
Adequate penetration and retention of CCA and CCB has been obtained in predried Borak Bamboo (Bambusa balcooa Roxb.), aboundantly grown in Bangladesh, with Full Cell Pressure Process. The treated bamboo can be used as building materials, the sufficient treatability ensured its long term best utilization at ground contact and indoors. Which will keep the environmental & socio economical conditions of Bangladesh more viable and normal.
A K Lahiry, S Begum, G N M Ilias, M A Matin Sheikh, M A B Fakir, M I Hossain
Analysing the characteristic role of moisture content for drying and fluid flow in Sitka spruce. - Part 1: The drying process of sapwood and heartwood of two different thickness of Sitka spruce using a kiln. - Part 2: Effects of moisture content on longitudinal permeability of Sitka spruce in vertical variation of the tree
2000 - IRG/WP 00-40173
The characteristic role of the moisture content in Sitka spruce (Picea sitchensis (Bong.) Carr.) that grown in the United Kingdom was examined by this study on the basis of (1) the reduction of moisture content in two different thickness of sapwood and heartwood by kiln drying process, and (2) the effects of moisture content to the longitudinal void volume filled of tanalith-C by the full-cell process from base (1 m) to apex (3 m) of the tree in sapwood zone. Accordingly, conclusions on indication of the drying process of sapwood and heartwood, and vertical variation of longitudinal flow with effects of moisture were listed separately: (1) Comparison of Drying Characteristic of Sapwood and Heartwood: The two different thickness (300x30x30 mm3 and 300x20x20 mm3) of sapwood and heartwood of Sitka spruce was dried using the suggested drying schedule in kiln. The reduction of moisture was schematically diagrammed according to sapwood and heartwood stakes. The reduction of moisture followed the same downward trend that sapwood (S) loses more moisture than heartwood (H) although the small stakes of S and H lost moisture rapidly compared with the large ones. (2) Vertical Variation of Moisture Content and Longitudinal Permeability: The 90 kiln dried defect free sapwood stakes (150x25x25 mm3) of Sitka spruce was taken from base to apex of the trees at 1, 2 and 3 m above ground level. After having the determination of moisture content in each experimental stake, the treatment was carried out by the full-cell process with CCA preservative (Tanalith-C) using a model pressure treatment plant. Significant differences observed among the tree heights from 1 to 3 m showing that slightly increases of moisture content from base to apex and conversely decreases of longitudinal void volume filled by preservative fluid.
The effects of density on vertical variation of permeability of Sitka spruce within tree
2000 - IRG/WP 00-40156
Tree improvement of Sitka spruce is a combination of silviculture and tree breeding aimed at producing higher quality products including increased growth rate and timber yield, and wood density. It is useful to know annual ring structure and density distribution when studying the quality of wood, grading it, or determining how the wood structure affects residual flow in softwoods. Since density is a factor under genetic control, the study in this article details the effects of density on longitudinal and radial permeability of Sitka spruce from base to apex. Comparison of overall means of both longitudinal and radial void volume filled (%) suggest that longitudinal permeabilities were almost the mirror image of those for the radial permeability along the tree trunk.
A behaviour of CCA penetration of fir (Abies bornmulleriana Mattf.) at different ramp times and constant vacuum/pressure applications
2006 - IRG/WP 06-40346
A behaviour of CCA penetration of Bornmulleriana fir (Abies bornmulleriana Mattf.) at different ramp times and constant vacuum/pressure applications was illustrated for the main flow directions by the experimental pictures.
I Usta, R Despot, M Hasan
Leaching of copper, chromium and arsenic from CCA-treated slash pine heartwood
1994 - IRG/WP 94-50020
Drying green slash pine with any of three high temperature drying schedules produced a product in which both the sapwood and the heartwood could be penetrated with CCA using a modified Bethell treatment schedule. Required H3 retentions were achieved in both sapwood and heartwood, from 200 litres per m³ charge uptake. Post-treatment fixation/drying was accomplished by three different regimes, including an accelerated fixation. Although acceptable preservative penetration and retention was achieved in the heartwood, arsenic fixation (as determined by both AWPA procedure E11-87 and U.S. EPA TCLP procedure) was inferior to that attained in the sapwood. TCLP leachates from 1 cm³ heartwood blocks contained up to 4.5 mg/l arsenic, very close to the maximum value (5.0 mg/l) currently permitted in Australia for arsenic waste disposal. Though there are clear advantages in achieving heartwood penetration, caution must be exercised to ensure that this step does not compromise the accepability of the product. No process modification could be accepted if it introduced possibilities of exceeding safe disposal limits for sawdust and offcuts, or building site contamination.
M J Kennedy, G Palmer
Preservation of two Indonesian timber species for marine environment purposes
1994 - IRG/WP 94-10079
This paper deal with the experiment of CCA full cell processed two non-durable Indonesian species for placed in the marine environment. 80 samples of 5 x 5 x 60 cm³ dried durian (Durio zibethinus) and mahogany (Swietenia mahagony) timber were CCA-full cell processed using 4 combination treatment of: without steaming; one hour steaming; 3% and 5% CCA solution concentration. 40 samples of them were field tested in the sea water in Rambut island beach near by Jakarta. The results shows that mahogany very difficult to treat and not recommended to be placed in marine environment, while CCA retention in durian timber could reach 29.91 kg/m³ and meet the requirement of retention for timber to be placed in marine environment. After two month field test in sea water full cell processed drian with 5% CCA solutin concentration could prevent marine borers attack.
P Permadi, I M Padlinurjaji, F Rasmita
Wood protection processes in the Asean countries
1994 - IRG/WP 94-40034
This paper presents the wood processing practices in the Asean countries composing Indonesia, Malaysia, Philippines, Singapore, and Thailand except Brunei. The development of wood preservation industry in these countries started as early as 1922 to 1960. As in other industrial countries, treatment pressure with creosote of utility poles, railway sleepers, and marine pilings are the prime commodities that require long term protection. The introduction of water-borne preservatives covered the treatment of sawn timber and other lignocellulosic materials. It covers the historical background and development of the industry in each country, treatment processes both pressure and non-pressure of commodities e.g. power poles, railway sleepers, marine pilings, housing components, furniture, and other lignocellulosic materials requiring protection against biological deterioration. Technical problems are common and varied due to different treatment standard specifications and preservatives specially water-borne types. The pollution aspect of preservating plants and the prohibition and control of some wood preservatives is a growing concern of the environmentalists. Wood preservation in the Asean countries will stay on and geared towards the treatment of industrial tree plantations, rubberwood, palms and bamboos.
F R Siriban
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 penetration of the product reveal that impregnation of Eucalyptus globulus though difficult is often possible. The highest average values were recorded in the small diameters, yet the standard deviation in all three classes is quite remarkable. Moreover fence-posts from the 1st rotation stand show a better behaviour with the treatment. There seems to be no significant correlation between absorption and initial vacuum or treating pressure times.
D De Sousa Castro Reimão, L Nunes
Investigation of temperature effect on fixation of Celcure preservative (ACC) in beech (Fagus orientalis)
2001 - IRG/WP 01-40200
In this research, the fixation speed of Celcure 2% (ACC) preservative salt, under temperature of 17°C, 27°C and 50°C, on intact and stained wood specimens of beech was investigated. For this purpose, blocks of wood with 5x5x7 cm dimensions were prepared and saturated with 2% ACC concentration by full-cell process. The specimens were put in three incubators at the above-mentioned temperatures. For measuring the percentage of fixation through time, the specimens were extracted by using hydraulic pressure equipment, under 69 Mpa pressure. The pH of extraction was measured with the method of diphenyl Carbazid and by using spectrophotometer. This measurement was done continuously and the amount of 6- valence chromium concentration present in the extract was compared with the amount of chromium concentration in the primary solution and then the percentage of fixation was calculated. The results showed that the decrease in 6-valence chromium is accompanied with increase of pH, this is due to absorption of positive hydrogen ion by 6-valence chromium for reduction to 3-valence chromium and also ion-exchange of active components with wood during the primary phase of fixation. Also, the time necessary for reaching complete fixation in intact and stained wood in the fixation temperature conditions of 17, 27 and 50°C were 1075, 501, 109 hours, respectively. In general, the results showed that temperature has effective role in accelerating of fixation process and in this respect, intact and stained wood did not show significant statistical difference.
A Karimi, M Ghorbani
The full guideline for the “double layer test method” - A field test method for determining the durability of wood out of ground
2004 - IRG/WP 04-20290
This guideline describes a test method for wood to be exposed to the weather out of ground contact. The main objective of the method is to evaluate the durability of wood in above ground exposure as shifted overlaid stakes, which form the so called double layer. The method is applicable to the testing of untreated, treated and modified wood. Initially it was developed and found to be most useful for testing of natural durability. As a simple and effective test method, it spread quite fast. Up to now more than 30 double layer tests are running in different countries of the world. The inventors of the double layer test were asked to come up with a full and precise guideline for this test methodology to enable interested scientist making use of this test method. Therefore this IRG- document was written as an instruction for those who would like to perform this test.
A O Rapp, U Augusta
Effect of treating process on efficacy of CCA in a laboratory decay test
1990 - IRG/WP 3628
Test samples of Pinus radiata sapwood measuring 40x40x500 mm³ were treated with a range of concentrations of the copper-chrome-arsenate (CCA) formulation "Tanalith C" using Rueping (empty cell), Lowry (empty cell) and Bethell (full cell) treatment processes. Samples were then reduced to 40x40x7 mm³ test blocks and exposed to the decay fungus Coniophora puteana using an agar/block technique. Replicate blocks were analysed for preservative components. Regression analyses of percentage weight losses of test blocks against total Cu+Cr+As retentions (TAE) showed differences in efficacy of the preservative when applied by the three different processes, the order of effectiveness being Bethell > Lowry > Rueping. Two hypotheses are proposed to explain the results: (1) Disproportionation within the wood of preservative salts when applied by empty cell processes, (2) Differences in distribution of preservative elements following treatment by the three processes.
M E Hedley, K Nasheri, J G Van der Waals
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 longitudinal penetration, which is usually conditioned by the length of the fence-post.
L Nunes, D De Sousa Castro Reimão
A novel guide for the determination of the physical properties of wood including kiln drying and full-cell preservative treatment
2004 - IRG/WP 04-20298
An ideal flow chart for the sequential experimental determination of a range of physical properties relevant to wood drying and subsequent preservation was designed as a novel guide to assist wood scientists. In this manner, data assembly and experimental processing are shown. This was designed according to experience and published literature. Aspects emphasised in this review were the physical properties which effect the manner of processing particularly in respect to preservative treatment of wood. For this purpose a total of 93 references covering 8 topics (descriptive wood anatomy, physical properties of wood, shrinkage and swelling, wood density, moisture content, fibre saturation point, wood drying (by oven and kiln) and liquid permeability) were reviewed.
I Usta, M D C Hale
Trial to determine a suitable schedule for radial and longitudinal treatment of plug samples by comparison of changes in the fluid retention and the treated area
2001 - IRG/WP 01-40211
A full-cell process was carried out using different treatment schedules for radial and longitudinal samples because of the anisotrophy of flow. When timbers are impregnated with preservatives much better penetrations are obtained via the end grain than laterally (across the grain). Therefore, suitable schedules for radial and longitudinal flow directions were determined in an trial experiment using locally grown Sitka spruce, Queen Charlotte Islands (QCI) provenance, from Beddgelert Forest in North Wales. The full cell experimental schedules used were: initial vacuum 15 minutes at -0.84 bar and various pressure periods that was 5 bar pressure in radial flow direction for 15, 45, and 60 minutes, 3 bar pressure in longitudinal flow direction for 3, 6, and 9 minutes. No final vacuum was applied. After the treatment, the fluid uptake was calculated, and the fluid retention was determined on a whole-block basis. After fixation, plugs were dried and cut longitudinally through the centre and copper penetration was determined by spraying a 1% solution of Chrome Azurol-S on the cut surface and observing the blue colour indicative of copper. The preservative penetration was then measured by image analyser as depth (mm) and as total treated area (%). From the experimental data, it was concluded that the suitable schedules are 5 bar pressure for 45 minutes for the radial flow direction, and 3 bar pressure for 7 minutes for the longitudinal flow direction. Therefore these schedules are suggested to be used to examine the permeability of the different seed origins in both radial and longitudinal flow directions.
A note on te seasoning, preservative treatment and suitability of debdaru (Polyalthia longifolia Benth & Hooker.) for poles
1995 - IRG/WP 95-40056
The main work is to determining the suitability of Debdaru (Polyalthia longifolia Benth.) as poles from Government and Village forests are investigated. The poles of Debdaru are easily treatable with CCA preservative by full-cell pressure method, but difficult to dry (air & kiln). Proper quality control must be maintain from procurement to treatment, specially during physical selection & drying (air & kiln) otherwise it may be discard as pole. Debdaru poles have been found suitable for power and Telecomunication lines with very keen care.
G N M Ilias, M D Rokib-ul-Hafiz
Chemical treatment of ten Amazonian timber species of low natural durability
1991 - IRG/WP 3640
The objective of this work was to evaluate the performance of 10 amazonian wood species of low natural durability, to treatment with CCA preservative (2% concentration): it was concluded that all species studied are easily treated with this preservative. The sapwood showed high absorption and total penetration. The heartwood is relatively easy to preserve, exception to Parkia nitidae (Fava), Qualea paraensis (Mandioqueiras), Erisma unicatum (Quarubarana), and Virola sp (Ucuúba), which presented some restrictions. Nevertheless, it does not mean that their treatment is impossible.
C S Neta, B F Vianez
Notes on a wood preservation industry in Medan, North Sumatera, Indonesia
1987 - IRG/WP 3405
This paper deals with a descriptive account on the development of a wood preservation industry in Medan, North Sumatera (Indonesia). The industry was established in 1974 when the State Owned Electicity Corporation decided to use wooden power poles for their distribution network in North Sumatera province. However, the use of wooden power poles was discontinued in 1981, so as the preservation industry was severely affected. Some notes on the results of the full cell process, particularly on the percentage of over- and under-charged treatment, is also described in this paper.
N Supriana, A Murad
The effect of rate of pressure application on preservative uptake along and across the grain of fir (Abies bornmulleriana Mattf.) at different ramp and constant pressure times
2004 - IRG/WP 04-20292
This study was particularly design to determine the preservative uptake at different ramp (rate of increase in pressure) and constant pressure times on longitudinal, tangential and radial penetrations of fir (Abies bornmulleriana Mattf.) which grown indigeneously in Turkey. The samples of 2 cm cubes of kiln-dried wood (nominated to 12% moisture content) were treated at different ramp times varied from very fast to very slow rates of pressure (bar) per time (seconds) at 5, 15, 30, 60, and 90 sec. and the maximum pressure of 4 bars -in the treating vessel to refusal- was applied at the constant pressure time for 5 min. The preservative uptake was determined as the percentage of void volume filled (VVF%) for either flow directions at each ramp time. The results showed that the VVF% was, as expected, markedly greater in the longitudinal flow direction than both in the tangential and radial flow directions. In comparison to the VVF% laterally, it was greater in tangential direction than in radial direction in either treatment schedules. In this issue, although the trend seemed to be the similar between the flow directions, quite different patterns were observed within each direction for penetration and ramp times. Accordingly, conclusions were listed separately for each flow direction.
Protection of rubberwood timber. Part 1: Impregnation with boron preservatives
1989 - IRG/WP 3551
Rubberwood (Hevea brasiliensis) were treated with a 3% proprietary mixture of borax/boric acid using three different treatment schedules i.e. full-cell, full-cell to refusal and full-cell with 12 cycles of vacuum/pressure. Freshly cut samples had mean preservative retentions of 187 kg/m³, 214 kg/m³ and 178 kg/m³ respectively. Pre-air dried samples for one week had retentions of 252 kg/m³, 308 kg/m³ and 282 kg/m³ respectively. An increase of pressure time from 45 minutes to 90 minutes allowed for slightly higher retention values. Preservative retentions of the core (20 mm² around the centre) from freshly sawn samples were 0.08-0.13% m/m BAE (boric acid equivalent), 0.04-0.19% m/m BAE and 0.04-0.21% m/m BAE for the full-cell, full-cell to refusal and full-cell with 12 cycles vacuum/pressure treatment respectively. Retention values of similar samples from the surface up to a depth of 10 mm were 0.36-1.51% m/m BAE for the 3 different treatments.
L T Hong, C C K Liew