Your search resulted in 815 documents. Displaying 25 entries per page.
CCA removal from treated wood by chemical, mechanical and microbial processing
1998 - IRG/WP 98-50101-26
Most preservative-treated wood produced and consumed in the U.S. is treated with toxic inorganic compounds containing copper, chromium, and arsenic. Because chromated copper arsenate (CCA) is fixed to the wood, treated wood has not been considered toxic or hazardous and is currently landfilled. Increasing public concern about environmental contamination from treated wood combined with increasing q...
C A Clausen, R L Smith
Measurement of electrokinetic potential to evaluate adsorption of quaternary ammonium salt
1991 - IRG/WP 3672
Measurement of z-potential in the wood treated with preservatives is suggested as a method for determination of the adsorption of preservative to wood. It has been found that measurement of z-potential of wood treated with quaternary ammonium salt type preservatives can be a useful method to determine the adsorptives phenomena of preservatives and by which there is a remarkable differences in the ...
Yeong Suk Kim
Electrodialytic remediation of a soil from a wood preservation industry polluted by CCA
1998 - IRG/WP 98-50101-14
Soil contamination is often found at wood preservation sites due to spills, dripping of excess preservatives and deposition of sludge associated with dissolved salts of copper, chromium and arsenic (CCA). The electrodialytic process is a promising heavy metal soil remediation technique. It is based on a combination of the electrokinetic movement of ions in soil with the principle of electrodialysi...
A B Ribeiro, A Villumsen, G Bech-Nielsen, A Réfega, J Vieira e Silva
A simple field apparatus for measuring relative gaff penetration and assessing the effect of additives for improving pole climbability
2000 - IRG/WP 00-20187
A simple apparatus for measuring and comparing the relative "hardness" of utility poles is described. This "slide-hammer" gaff penetration apparatus was designed as a field testing unit to measure the depth of gaff penetration into test poles after application of a uniform and reproducible force to the gaff. The apparatus is simple to use in both the laboratory and field. Data is provided for resu...
A R Zahora
The effects of pH on leaching of copper-chrome-arsenate (CCA) from pressure-treated Kenyan-grown Eucalyptus saligna and Acacia mearnsii: Initial findings.
2002 - IRG/WP 02-30298
The effects of pH on leaching of CCA from pressure-treated Kenyan-grown Eucalyptus saligna and Acacia mearnsii were tested under laboratory conditions. Small samples of the two species (100mm x 30mm x 40mm) were smooth sawn from 8-year old trees to represent equal amounts of both sapwood and heartwood, air-dried to 12% moisture content, end-sealed, and pressure-treated at a commercial treatment p...
R Venkatasamy
Effect of humidity and temperature on fastener withdrawal resistance from CCA and ACZA treated Douglas-fir
2000 - IRG/WP 00-20209
The effects of preservative treatment on fastener withdrawal was investigated in Douglas-fir lumber conditioned to two moisture regimes. In general, conditioning samples to 19% moisture content produced more substantial changes in withdrawal resistance of galvanized fasteners than did conditioning to 12%. Treatment had little or no effect on withdrawal resistance of stainless steel fasteners. With...
Sung-Mo Kang, J J Morrell
Long-Term Release of Arsenic, Chromium, and Copper from CCA-Treated Wood and Ash
2005 - IRG/WP 05-50227
In this study, laboratory long-term leaching studies were conducted to characterize the leaching behavior of arsenic, chromium, and copper from CCA-treated wood samples (block, chip, and sawdust) and CCA-wood ash and to determine the rate of release of the metals from the CCA wood products. The leaching solutions were periodically collected and analyzed for the concentrations of arsenic, chromium,...
Hyunmyung Yoon, Heeseok Kang, Yong-Chul Jang
Borate diffusion from fused borate rods in douglas-fir transmission poles
1994 - IRG/WP 94-30042
Pressure-treated utility poles have given many years of excellent service, but their lifetime is often shortened by internal decay of the untreated heartwood center, particularly in refractory species, such as Douglas-fir. This paper reports the distribution of boron from fused borate rods installed in CCA-treated Douglas-fir transmission poles. The boric acid equivalent was roughly monitored by t...
T L Highley, W Finney, F Green III
Relating CCA fixation to leaching of CCA components from treated products
1995 - IRG/WP 95-50045
The relationship between chromium fixation in CCA-C treated wood, as determined by CrVI analysis of solution expressed from treated wood and the leaching of Cu, Cr, As and CrVI in a simulated rain test are evaluated for dimension lumber (2"x6") and pole sections. Leachate concentrations after 2 hour exposure to a misting spray (about 300 mm cumulative rainfall) decrease rapidly with increased degr...
P A Cooper, R MacVicar, Y T Ung
Wood cement composites using spent CCA treated wood
1999 - IRG/WP 99-50126
The feasibility of using spent or out-of-service CCA treated wood as a component of wood/cement composites was evaluated. Cold pressed wood particle cement boards were made using CCA treated particles from a red pine (Pinus resinosa Ait.) pole removed from service and from untreated red pine wood from a new pole. Boards were manufactured using a range of wood to cement ratios and water to cement r...
Chen Huang, P A Cooper
Kinetics and mechanism of fixation of Cu-Cr-As wood preservatives. Part 4: Conversion reactions during storage
1974 - IRG/WP 332
Precipitates simulating those produced in wood by preservative fixation reactions were prepared by the reduction of Boliden K 33 and Celcure AP solutions with hydrogen peroxide and hydrazine. The pH changes on aging at 20 and 50°C were studied and related to the chemistry of fixation previously described. Hydrolysis of copper arsenates may render arsenic acid temporarily water soluble pending pre...
S-E Dahlgren
Effect of soil chemistry and physical properties on wood preservative leaching
1998 - IRG/WP 98-50111
When treated wood is placed in contact with soil, complicated mass transfer and chemical reactions occur which causes the preservative components to leach from the wood. There are several factors that are known to affect the amount of chemical leached from wood. These are properties of the preservative and carrier, preservative retention, degree of fixation, exposure time, grain orientation, surfa...
Joan-Hao Wang, D D Nicholas, L S Sites, D E Pettry
Ecotoxicological effects of exposed CCA preservative treated wood in environments
2001 - IRG/WP 01-50173
For the evaluation of environmental effect of CCA treated wood exposd in the field, the simulated soil pot system of the laboratory was used. The effective components of preservatives were leached and determined after artificially conditioning a soil pot of CCA treated wood with more than 500mm water, the average monthly precipitation. As the water passed through the soil, As, Cr and Cu in the soi...
Dong-heub Lee, Dong-won Son
Experimental variations in the distribution of CCA preservative in lignin and holocellulose as a function of treating conditions (temperature, concentration, pH, species, and time)
1984 - IRG/WP 3277
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 3x3x4x2 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, a...
A Pizzi, E Orovan, M Singmin, A Jansen, M C Vogel
Fixation and leaching characteristics of Douglas-fir treated with CCA-C
2004 - IRG/WP 04-50213
Fixation and leaching characteristics of CCA-treated Douglas-fir was evaluated using the expressate method and the AWPA E11-97 leaching procedure. CCA fixation, as monitored by the chromium reduction, was much faster in heartwood than in sapwood; however, copper and arsenic fixation in heartwood appeared to be incomplete regardless of the extension of fixation time. This poor fixation of copper a...
Gyu-Hyeok Kim, Yun-Sang Song, Dong-heub Lee
CCA type C depletion of Southern yellow pine utility poles
1995 - IRG/WP 95-50049
Depletion and redistribution of preservative components were evaluated on five CCA-C treated poles in service for over six years in Conley, Georgia. A statistical approach was taken in which retentions below ground were compared to retentions above ground due to a lack of initial data on individual poles. It was hypothesized that the below ground retentions should be lower than the corresponding a...
P D Osborne, R F Fox
Conforming to European standards on preservative treatment
1998 - IRG/WP 98-20150
New European standards require that specifications for the preservative treatment of timber are written in terms of the penetration and retention of preservative within the treated commodity that result from the treatment process. In order to check compliance with this type of specification, suitable methods of quantitative analysis must be available. This paper presents the results of a study by ...
E D Suttie, R J Orsler
Effects of the sulfuric acid modification of CCA treating solution
1987 - IRG/WP 3415
Sulfuric acid modification of CCA treating solution is often used to control the formation of sludges and undesirable deposits on the surface of treated wood. The consequences of sulfuric acid addition are examined in this work and negative effects are shown to far outweigh any benefits. Major risks include the loss of copper due to leaching from treated wood and the accelerated corrosion of treat...
R F Fox, H J Fry, E A Pasek, A S Ross
The potential of high pressure pulsation processes to treat white spruce lumber with water-borne preservatives
1988 - IRG/WP 3471
Laboratory work using end sealed 4x8x46 cm³ white spruce samples has been done to explore the suitability of three variants of a 2.1 MPa pulsation process for the impregnation of white spruce with CCA. The results showed that the process improved significantly the penetration of the preservatives and reduced significantly cell collapse, when compared with the results of treatment using a 2.1 MPa ...
J P Hösli, J N R Ruddick
Residual CCA levels in CCA treated poles removed from service
2000 - IRG/WP 00-50152
Fifty-two CCA treated poles removed from service after 1 - 50 years were sampled at different depths from their below ground and above ground zones and the preservative levels and mass balances related to the location in the pole and pole age. Generally CCA retentions were still well above the toxic threshold for decay in even the oldest poles. This confirms the good leach resistance of CCA and th...
P A Cooper, D Jeremic, J L Taylor
Wood preservation in Uruguay
1987 - IRG/WP 3404
The purpose of this paper is a brief description of the current status of wood treatment in Uruguay. The forest resources of the country are summarized, the environment, their economic importance and future potential. The present wood treating facilities are described, together with the chemicals used and the standards generally accepted. Wood treated products used in the Uruguayan market are cite...
G Baillod
Interactions between soft rot fungi and CCA preservatives in Betula verrucosa
1988 - IRG/WP 1367
Ultrastructural investigations were carried out to obtain information on the cell wall distribution of CCA elements during soft rot decay of 4% K33 CCA preservative treated birch (Betula verrucosa) wood. TEM observations on fibres at various stages of S2 cavity formation by mutabilis showed a distinct pattern of electron dense materials to occur within the S2 cell wall region. These materials (gra...
G F Daniel, T Nilsson
Leachability of active ingredients from some CCA treated and creosoted poles in service. A progress report after 10 years testing
1990 - IRG/WP 3627
CCA K33 TYPE B treated or creosoted poles, 10 pieces of each treatment type, have been monitored from the treatment plant to an electricity line, which was build up in Southern Finland in 1978. Preservative retention was determined by taking borings at four different levels: 1.5 m from the top end, 1 m above ground line, ground line and 0.5 m below ground. Determinations were made before setting u...
A J Nurmi
PXTS; A Metal Free Oligomer Wood Preserving System - A Summary of Data To Date
2004 - IRG/WP 04-30350
The world is continually looking for new wood preservative technology, especially to address environmental concerns. Recent changes in the USA have limited the use of arsenical containing formulations to industrial use through a negotiated voluntary cancellation of most residential label uses. PXTS (Polymeric Alkylphenol Polysulfide) offers a brand new technology that is an all organic system, lik...
M H Freeman, D D Nicholas, D Renz, R Buff
Environmental Impacts of CCA-Treated Wood: A Summary from Seven Years of Study Focusing on the U.S. Florida Environment
2003 - IRG/WP 03-50205
Wood treated with chromated copper arsenate (CCA) was identified in 1995 as the cause of elevated arsenic concentrations within wood fuel used for cogeneration within Florida. Since this time a research team from the University of Miami and University of Florida has evaluated the environmental impacts of CCA-treated wood within the State. Research has focused on two distinct areas: in-service l...
H M Solo-Gabriele, T G Townsend, J D Schert