Your search resulted in 396 documents. Displaying 25 entries per page.
The effect of felling time of year on CCA fixation rate and quality of selected hardwoods
1998 - IRG/WP 98-40116
White birch (Betula papyrifera), poplar (Populus sp.) and red maple (Acer rubrum) trees were harvested in winter, in spring, before the leaves flushed, after leaf flush and later in the summer. Sapwood discs were cut from the freshly felled trees, dried and cut into 25 mm and 19 mm cubes. The cubes were pressure impregnated with CCA-C and fixed under high relative humidity and at 50°C or at room ...
Y T Ung, A Taylor, P A Cooper, D P Kamdem
Controlled fixation technology
1995 - IRG/WP 95-50040-12
Controlled fixation techniques have been developed and adopted in a number of countries where chromium containing preservatives are predominantly used. The purpose of this technology is to reduce both on-site pollution and holding requirements for freshly treated timber. The fixation mechanism is complex and the time taken to complete the reaction is dependent upon a number of factors. A number of...
M Connell, W J Baldwin, T Smith
Sludge formation in timber treatment with CCA preservatives. Origin and elimination
1984 - IRG/WP 3276
The exact distributions between lignin and holocellulose and retentions on wood of copper, chromium and arsenic as a function of various sets of conditions in a factorial experiment in which combinations of three temperatures of treatment, three CCA solution concentrations, four pH's of the initial CCA solution and two timber species, namely Pinus radiata and Eucalyptus grandis, are repor...
A Pizzi, W E Conradie, A Jansen
Preservative treatement of muli bamboo (Melocanna baccifera) by pressure process
2001 - IRG/WP 01-40194
This study was carried out in order to investigate the possibility of preservative treatment of split bamboo by pressure process. Whole bamboo is very difficult to treat by pressure process, which is the best and most dependable of all treating processes. Because it surface has a coat of impervious cutiular which make it very resistance to the penetration of liquid. Beside this it is prone to deve...
K Akhter, M Younusuzzaman, M H Chowdhury
A comparative study of CCA type C and B treated poles in service
1993 - IRG/WP 93-50001-05
CCA K33 type B and C treated utility poles, 9 pieces of each treatment type, were analyzed for preservative retention after 11 years in use. Borings were taking 1 m above and 0.3 m below the ground line. Also total amount of copper, chromium and arsenic was determined in soil surrounding the poles. The solubility of these active components in soil was monitored by using different leaching procedur...
A J Nurmi
Fixation of chromated copper arsenate (CCA) wood preservative in Australian hardwoods: A comparison of three Eucalyptus species
1996 - IRG/WP 96-30107
New environmental guidelines for the management of CCA treatment plants were released in Australia in 1995. This has stimulated interest in techniques for controlling or accelerating the fixation of CCA in freshly treated timber products. The ability to understand, then effectively control and/or accelerate fixation of CCA in treated timber products can be an economic, technical and environmental ...
J Holmes
Effect of treatment process on performance of copper-chrome-arsenate. Part 2: Field stake tests
1995 - IRG/WP 95-40046
Pinus radiata sapwood stakes 20 x 20 x 400 mm³ were treated with CCA Type C using a range of concentrations and three treatment processes; Bethell, Lowry and Rueping. Preservative retention was determined by chemical analysis of treated material. Following fixation stakes were installed in a randomised plot in the Whaka graveyard located on the FRI campus. Stakes were inspected at yearly interval...
M E Hedley, J Anderson, J B Foster, B E Patterson
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
Leaching Characteristics of Copper in Copper Treated Wood
2003 - IRG/WP 03-30316
The leaching characteristics of copper in copper treated bamboo and other wood species such as slash pine and poplar has been conducted in this paper according to AWPA M11-87 standard, the result indicates that:
--Copper fixation rate of salts from organic acids such as citrate and oxalate and malate is less than other non-organic acid formulations.
--Copper fixation rate of oven-dried bamboo sa...
Mingliang Jiang, Junliang Liu, Daochun Qin, Yamei Wang, Zehui Jiang
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...
P Permadi, I M Padlinurjaji, F Rasmita
Determination of fixation properties by bioassays - A proposal for the assessment of safety indexes in wood protection
1990 - IRG/WP 3566
In the determination of environmental effects of chemicals tests with fishes, daphnia and algae have proved to be practicable. With respect to wood protection such bioassays are suitable to control effects of treated timber against aquatic organisms. By using the fish-acute-toxicity-test the development of a laboratory test method is described for the checking of the fixation rate of a copper-chro...
H-W Wegen
Accelerated laboratory soil contact decay test using soil amended with composted wood
2004 - IRG/WP 04-20284
The effect of amending soil with wood compost on the decay rate of wood wafers in contact with the unsterile soil, as measured by radial compression strength loss, was explored. It was found that the addition of composted wood to the soil significantly increased the wood decay rate. The reason for this acceleration in wood decay is not entirely clear, but appears to be at least partially associate...
D D Nicholas, H Borazjani, T Schultz
Leaching and fixation characteristics of chrome-copper-fluoride-zinc (CCFZ) treated wood
1996 - IRG/WP 96-30096
The leaching characteristics of radiata pine sapwood blocks treated with CCFZ were evaluated by the AWPA standard leaching test. The rate of fixation of the preservative components in CCFZ treated radiata pine were also evaluated by quantitative analysis of solution expressed from the treated wood. Both leaching and fixation characteristics of CCFZ were compared with CCA-Type C treated wood sample...
Gyu-Hyeok Kim, Jong-Bum Ra
Practical consequences of the clarification of the chemical mechanism of CCA fixation to wood
1983 - IRG/WP 3220
Practical consequences derived from the chemical investigation of the mechanism of fixation of CCA to the wood constituents are discussed. Among these, formulas for the calculation of the time of hexavalent chrome fixation are presented. Furthermore, three parameters are shown to be important to the long-term effectiveness of CCA-treated timber: (i) the temperature of treatment, (ii) the initial p...
A Pizzi
Environmental situation on wood preservation industries in Bangladesh
2000 - IRG/WP 00-50148
The hazard that wood preservative chemicals pose to people and the environment is serious. The lack of information, legislation and awareness create an unfavorable situation on wood preservation industries. In this regard, three wood preservation industries have been visited to collect the information about pollution. It was observed that different steps have been taken to minimize the contaminati...
K Akhter
Comparison between agar-block and soil-block methods for wood-destroying Basidiomycetes
1992 - IRG/WP 92-2401
The object of this work is to compare these methods in order to provide some information to help in the choice between them. The comparison was made by a statistical analysis (factorial completely randomized design) and by a discussion about other aspects of each method. An evaluation of some fungi on attacking wood and a comparison between Picnoporus sanguineus isolated from carpophore and decaye...
M B B Monteiro, S Brazolin, G Catanozi
Proposal for further work on fixation of CCA-preservatives in wood
1988 - IRG/WP 3493
Many studies on the fixation and fixation-mechanism of CCA-preservatives in lignocellulose materials have been published but few on the practical consequences of this knowledge. For the wood preserving industry and the user of treated wood it is important to know what is meant by the word fixation, when fixation is complete and how fixation can be recorded in an easy way according to a non-destruc...
M-L Edlund
Fungus cellar testing as an evaluation method for performance of treated timber in ground contact
2001 - IRG/WP 01-20227
A fungus cellar method for the accelerated evaluation of performance of treated wood in ground contact is described. The test soil comprised of sandy loam, vermiculite and Japanese horticulture soil "Kanumatsuchi" in a ratio of 6:2:2 by volume. The soil was inoculated with the dominant test fungus isolated with selective medium from decayed wood samples. Pairs of treated and untreated wood specime...
Y Nagano
CCA modifications and their effect on soft rot in hardwoods. Part 2
1983 - IRG/WP 3244
The work outlined in this document is a continuation of that presented in Document No: IRG/WP/3201. The findings described in the previous paper are summarised below: a double treatment of CCB followed by arsenic (CCB+A) is more effective than a double treatment of boron followed by CCA (B+CCA) or a single treatment of CCA, CCB or CCAB in controlling soft-rot due to Chaetomium globosum in birch. C...
S M Gray, D J Dickinson
Attempt for developing a new method for above ground field testing of wood durability
2000 - IRG/WP 00-20199
Field testing remains the most appropriate way for evaluation of wood preservatives or natural durability of wood species. Above ground tests are designed to answer specific questions concerning the outdoor utilisation of wood. Such methods supply additional information and confirm or reject preliminary laboratory results. The European standard (ENV 12037, "lap-joint") for assessment of the durabi...
N Terziev, M-L Edlund
Fixation and leaching of selected Malaysian tropical hardwood after treated with CCA
2001 - IRG/WP 01-40207
The objective of this study is to investigate the fixation and leaching properties of selected Malaysian tropical hardwood (sentang wood (sapwood and heartwood) and rubberwood) after being treated with copper chrome arsenate (CCA) type-C preservative. The samples were treated with retention level of 0.5%, 2.0% and 5.0%. The samples were leached and the leachate were analyzed by AAS and the amount ...
R Hashim, O Sulaiman, Tan Siew Ching, K Yamamoto
Effectiveness of CCA fixation to avoid hexavalent chromium leaching
2002 - IRG/WP 02-50187
It is generally assumed that hexavalent chromium in chromated copper arsenate wood preservative is substantially reduced to trivalent chromium during fixation and that the potential to leach the more toxic CrVI is minimal. However, there are occasional claims some hexavalent chromium remains in wood after fixation and that small amounts of CrVI are available for leaching. One problem is that ot...
P A Cooper, D Jeremic, Y T Ung
Service life of pressure treated deckings of spruce in direct contact with the ground
1988 - IRG/WP 3463
For decking outdoors in Sweden, pressure treated Scots pine (Pinus sylvestris L.) is used, on account of its treatability. The feasibility of using instead the refractory Norway spruce (Picea abies Karst.) is tested in a field trial. The spruce decks were treated together with pine decks with an ordinary Bethell process. As yet, after more than four years of exposure, neither in the battens nor in...
J B Boutelje, T Sebring
Wood preservation in Kenya
2000 - IRG/WP 00-40190
Focussing an Wood Preservation in Kenya, the Report discusses and elaborates on Education and Training, Research, Wood deteriorating organisms, Treatment Plants and Processes, Preserving Chemicals, Specifications, Markets, Health and Safety and Environmental issues. Education and Research is limited to one Institution only, other Institutions involved with the properties and utilization of wood ha...
R Venkatasamy
A suggestion for the improvement of the chemical protection of wooden poles
1987 - IRG/WP 3445
Insufficient drying of white poles in Sweden causes inadequate penetration of the impregnation compounds, CCA salts and creosote, in a varying proportion of the treated poles, and with pretreatment decay present, sooner or later, internal fungal attack in the ground-line zone of the standing poles is the result. The application of a diffusing fungicide in the ground-line zone in connection with th...
H Friis-Hansen