Your search resulted in 275 documents. Displaying 25 entries per page.
Disposal of CCA treated waste wood by combustion - An industrial scale trial
1996 - IRG/WP 96-50068
Totally 272 m³ (62.7 t) of CCA treated utility poles were chipped and incinerated at Jalasjärvi Gasification Plant. In average the whole batch of chips contained 57 kg of elementary copper, 95 kg chromium and 76 kg arsenic. During the 56 h combustion trial the measured arsenic emission to the air was 76 g in total. Copper and chromium emission was less than 1 g. The condensing water from the coo...
A J Nurmi
Wood preservation in Kenya
2000 - IRG/WP 00-40191
Current research on wood preservation in Kenya is mainly on the development of biological control of wood-destroying termite species, using mycoinsecticides. The major research institutions include the Kenya Agricultural Research Institute (KARI), Kenya Forestry Research Institute (KEFRI), Moi University and the International Centre for Insect Physiology (ICIPE). Training institutions include Fore...
G Ochiel
Copper binding capacity of modified wood flour
1992 - IRG/WP 92-3709
Wood flour was modified by reaction with oxidising agents and CCA preservative. The copper chromium and arsenic were removed from the CCA treated wood flour by an acid leaching procedure. The modified wood flours were allowed to react with copper acetate solution and the level of copper fixation achieved was determined. The modified wood flours had greater affinity for copper ions present in solut...
N C Milowych, W B Banks, J A Cornfield
Fixation of CCA in Pinus sylvestris after kiln-drying
1990 - IRG/WP 3594
Tanalith C Paste is 98% fixed and Tanalith Oxide C is 99% fixed irrespective of whether treated Pinus sylvestris is kiln or air dried. A schedule suitable for kiln drying of CCA treated Pinus sylvestris is described....
P Warburton, J A Cornfield, D A Lewis, D G Anderson
The effect of treatment temperature on the biological performance of CCA treated wood
1990 - IRG/WP 3624
Birch and Scots pine sapwood blocks were treated with several concentrations of CCA at three different temperatures: 5, 20 and 35°C. The treated wood was maintained at the appropriate temperature for the fixation period. Leached and unleached samples were then exposed in a soft rot monoculture test using Chaetomium globosum and a brown rot monoculture test using Coniophora puteana. The treatment ...
S M Gray
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, incl...
M J Kennedy, G Palmer
The course of fixation of Cu-Cr-As wood preservatives
1972 - IRG/WP 307
Copper-chrome-arsenic (CCA) preservatives in contact with wood result in an instant extensive increase of pH, because of ion-exchange and adsorption reactions with the wood. During precipitation of the active elements the pH continuously increases but reaches a maximum, when all chrome is consumed. Some of the early reaction products are unstable and slowly convert via dissolution into stable comp...
S-E Dahlgren
Chromium on the surface of CCA-treated wood
1978 - IRG/WP 386
Chromium in solutions of CCA preservatives is predominantly in the hexavalent state (Cr VI). It is well known that Cr VI is associated with dermatitis and skin ulceration in workers handling chromium containing products and processes. When reduced to the trivalent state, however, chromium is considerably safer. An essential part, therefore, of safety procedures in any chromium - using industry is ...
C R Coggins, P Hiscocks
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
Investigation of the fixation in wood of chromated zinc chloride and copperised chromated zinc chloride preservatives
1976 - IRG/WP 372
A biological method of evaluating the extent to which CZC and CCZC preparations are retained in wood in terms of the potential protection which they afford against destruction by Merulius lacrymans (dry rot) is given. CCZC is recommended for protection of wood under moderate leaching conditions, while the use of CZC under such conditions is not recommended....
V N Sozonova, D A Belenkov
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
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
Soft rot tests
1983 - IRG/WP 2206
At the IRG meeting in Turkey it was proposed that developments in testing preservative-treated wood in unsterile soil according to techniques variously described as "fungus cellar", "soil-bed", or "accelerated field simulation" be considered along with conventional laboratory procedures as the basis for a standard test. Before formulating any co-operative test programme it is essential to examine ...
J A Butcher
Ground contact performance of wood treated by the MSU process
1990 - IRG/WP 3609
Environmental concerns have prompted a renewed interest in accelerated fixation schemes for CCA-treated wood. Results from stake tests of southern pine (Pinus sp.) treated using a conventional Bethell cycle are compared with matched stakes treated using the MSU Process. The effects of adding boric acid to the preservative formulation are also discussed. Differences among test plots are discussed....
H M Barnes, T L Amburgey, R W Landers
The influence of formulation on the behaviour of LOSP's during industrial impregnation of spruce
1986 - IRG/WP 3387
Evidence is presented that the comparative behaviour of two LOSP formulations during impregnation treatment of spruce cannot be predicted purely on the basis of their physical characteristics (viscosity, surface tension and contact angle) nor on the extent of their 'passive' penetration into pine sapwood....
L D A Saunders, D M Zuvencko
Natural Durability Classification Systems Used Around the World
2009 - IRG/WP 09-10694
Around the world natural durability is classified in different ways. The nature and rigor of the tests used to measure durability, the method of classification based on these data, and use of these classifications to specify end uses or predict service life all vary. This can lead to confusion among people not familiar with the various systems used. This review describes the methods used to classi...
R Stirling
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
Acceleration of the fixation of chromated wood preservatives by UV-radiation
1989 - IRG/WP 3544
Preliminary laboratory tests demonstrated that the fixation of chromated water-borne wood preservatives may be accelerated by UV-radiation. The degree of fixation depends on the intensity of radiation and the prevailing temperature. Three hours radiation at 20°C in a device for artificial weathering diminished the leaching of chromium to 43% and of copper to 23% compared to not-radiated samples. ...
H M Illner, H Willeitner, K Brandt
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
Xenon simulation of natural weathering of external joinery preserving - Finishing systems
1992 - IRG/WP 92-2412
Semitransparent wood stains ('lazures') for external joinery have developed by means of product combination towards complete wood finishing systems that are easy to applicate, have a good weathering resistance and low maintenance cost. The search for enhanced formulations and the possibilities to standardize these products or treatment systems are always facing long periods of we...
J Van Acker, M Stevens, M Nys
Resistance of painted wood to mould fungi. Part 2. The effect of wood substrate and acrylate paint systems on mould growth
1997 - IRG/WP 97-10234
Resistance of acrylate paint systems on different types of pine and spruce sapwood to mould fungi was studied. Dipping into the preservative prior to painting, a primer with and without a fungicide (propiconazole + IPBC 0.50 + 0.2%) and a topcoat with and without a fungicide (propiconazole + IPBC 0.25 + 0.12%) were combinations of the treatments studied. The efficacy of the treatment systems varie...
H Viitanen, P Ahola
The Chemical and Biological Properties of Polymeric Betaine
2009 - IRG/WP 09-30512
Didecyl polyoxyethyl ammonium borate (DPAB), also known as Polymeric Betaine, was developed as a co-biocide for chromium-free copper based wood preservatives in Europe in the 1980’s. DPAB as a wood preservative has been reported previously. This paper summarizes the chemical, physical, and biological properties of DPAB. ...
H Härtner, S Schmitt, Futong Cui, H M Barnes
Evaluation of Barrier Wrap Systems after 71 Months of Exposure
2013 - IRG/WP 13-40631
A 71 month study of the performance of booted samples in ground contact was conducted in AWPA hazard zone 4. Data indicated that excellent performance of wrapped systems, even over untreated wood, could be obtained. Instances of decay colonization or termite attack could all be attributed to some breaking of the integrity of the barrier system. Good performance for treatment below ground contact...
H M Barnes, M G Sanders, G B Lindsey, C McIntyre
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