Your search resulted in 62 documents. Displaying 25 entries per page.
Rapid analysis - chances and limitations
1999 - IRG/WP 99-50130
The reuse of wood out of service in the particle board industry demands a proper handling and separation of assortments with differing content and nature of preservative. A pre-selection based on visual and olfactorial characteristics can be carried out for certain assortments like sleepers, poles, etc. Problems arise from diffuse and less intensive treated wood which is regularly dip-treated or b...
A Peylo, R-D Peek
Possibilities of improving the oscillating pressure method
1991 - IRG/WP 3668
Studies on the dynamics of pressure changes in wood during impregnation revealed no significant effect of fast pressure changes for green spruce as used by OPM (IRG/WP/3615). The following experiments were carried out on several hundreds of spruce palisades to examine the modification of single procedure parameters of common use OPM and to record the effects on the impregnation result with the aim...
S Goetsch, R-D Peek
Curing conditions for a low formaldehyde etherificated melamine resin
1998 - IRG/WP 98-40108
Waterbased methanol etherificated melamine formaldehyde resins have the potential to increase the resistance of impregnated wood against wood destroying fungi. Previous studies indicated that the resin with the lowest formaldehyde content tested showed the best results regarding fungal resistance, dimensional stability and formaldehyde emissions after curing. In the present paper the influence of ...
D Lukowsky, R-D Peek, A O Rapp
The natural durability story
1997 - IRG/WP 97-20119
Wood species with superior natural durability were in use since the beginning of timber utilisation. Their importance decreased with increasing industrial timber impregnation. In recent time, however, they gained worldwide new interest due to environmental problems involved with treated timber. In Europe a special Standard (EN 350) has been published and a multinational research project on testing...
H Willeitner, R-D Peek
The non-uniform uptake of chromium and copper during the impregnation of wood using the example of a CCB-salt
1998 - IRG/WP 98-20137
The correct impregnation of wood requires among other things a regular control of the concentration of the treating solution as this and/or its stoichometric composition can change as a result of the impregna-tion process and the treated wood. The preferential uptake of individual wood preservative components by the wood is of particular importance in this connection.
Dipping and vacuum impregnat...
P Jüngel, E Melcher, R-D Peek
Determination procedure for wood preservatives in waste wood - statistics of sampling and analysis
1998 - IRG/WP 98-50121
In a RTD research programme funded by the German Federal Environmental Agency (UBA - Report No. 126-06-010103) a standardised and validated procedure was developed for sampling and analysing wood preservative components in waste wood. For this investigation a realistic quantity of waste wood from house demolition was used and 80 components analysed. The examination of single wood pieces and woodch...
P Stolz, J Krooss, U Thurmarm, R-D Peek, H Giese
Microbial decomposition of salt treated wood
1993 - IRG/WP 93-50001-22
Specialized microorganisms which are able to convert fixed inorganic preservatives from treated wood into water soluble components are investigated. A number of brown rot fungi like Antrodia vaillantii have been isolated from cases of damage and examined under unsterile conditions with CCA-, CCB-, CCF- and CC-treated wood at retention levels of at least 50% higher than recommended for wood in grou...
R-D Peek, I Stephan, H Leithoff
Biological detoxification of wood treated with salt preservatives
1992 - IRG/WP 92-3717
The use of microorganisms that are capable to convert chemically fixed inorganic preservative complexes from impregnated wood waste into watersoluble components is investigated. A number of fungi were isolated from deteriorated and initially well-treated wood. They revealed an exceptionally high production of organic acids (pH 2). The fungi were identified and used together with others of the same...
I Stephan, R-D Peek
Biological resistance of wood treated with waterbased resins and drying oils in a mini-block test
1998 - IRG/WP 98-40107
In recent years it was found that the resistance of wood against fungal degradation could be increased by impregnation with an etherificated melamine formaldehyde resin. Using this resin as a reference, a waterbased fatty acid modificated alkyd-resin and two drying-oils were assessed for their biological performance in a mini-block laboratory test. Although drying-oils, like linseed-oil, are often...
M Sailer, A O Rapp, R-D Peek
Laboratory testing of wood natural durability - In soil-bed assays
1998 - IRG/WP 98-20141
Laboratory methods for assessing wood decay resistance are being investigated in the framework of an ongoing European research project. This paper summarizes the main results obtained for soil-bed tests based on the European prestandard ENV 807-Test 2. The data suggest that this testing methodology is suitable for evaluating the natural durability of timber species in soil-contact under conditions...
R Sierra-Alvarez, I Le Bayon, J K Carey, I Stephan, J Van Acker, M Grinda, G Kleist, H Militz, R-D Peek
A comparison of the migration behaviour in soil of different waterborne wood preservatives and their leachates
1997 - IRG/WP 97-50091
Lysimeter tests were carried out on water-soluble wood preservatives and on wood preservative components leached out of impregnated wood. The purpose of these tests was to determine the extent to which the migration behaviour of environmentally relevant ions in the soil is influenced under comparable conditions. The results clearly show that the groundwater is especially at risk when wood preserva...
E Melcher, R-D Peek
Emissions from the combusting of boron and fluoride containing wood
1995 - IRG/WP 95-50040-18
The combustion properties of waste wood and wood residues containing wood preservatives were investigated in several test series after having been blended with untreated wood at a ratio of 1:4. The results for CFB, SF and boric salt show that, provided an optimized combustion, the concentrations of the stack pollutants correspond approximately with those found for untreated wood. Only during the c...
T Salthammer, H Klipp, R-D Peek
Emissions from the combustion of wood treated with organic and inorganic preservatives
1994 - IRG/WP 94-50019
Wood waste and industrial wood residues often contain various preservatives. The waste management for these residuals can be recycling, deposition or combustion. Among the three possibilities, combustion seems to be the most efficient way of usage. To obtain more information about the emission properties of treated wood, different materials were incinerated in different furnaces after mixing with ...
T Salthammer, H Klipp, R-D Peek, R Marutzky
Utilization of coconut timber from north Sulawesi, Indonesia. Part 1: Durability
1994 - IRG/WP 94-30044
Coconut timber from non-productive plantations is a byproduct of an agricultural crop and, by the same token, constitutes a renewable resource which may serve as a complement to or, at least in part, as a substitute for traditional timbers in local markets. Its more extensive utilization is expected to contribute to the conservation of tropical rain forests. Export of coconut timber and/or wood pr...
R-D Peek
The fate of salt preservatives in facility yard soils and decontamination of soils and drainage waters
1993 - IRG/WP 93-50001-25
Extensive studies during the past 10 to 15 years revealed that noticeable amounts of preservative components may be released in the environment by dripping off or by rain prior to fixation unless adequate precautions are taken. Therefore, soil and groundwater contamination especially from chromium-VI compounds but also from other inorganic and organic constituents exist in impregnation plants, pos...
R-D Peek, H Klipp, K Brandt
Water-based silicones on wood
1997 - IRG/WP 97-30144
Five waterbased silicones commonly used on masonry where tested as water repellents for wood. The Water Repellent Effectiveness was determined by swellometer-tests and by measuring the water uptake of samples after 24 hours complete immersion and by immersion in a water level of 4 mm for 24 hours. The different methods are compared and discussed. Artificial and natural weathering was performed to ...
D Lukowsky, R D Peek, A O Rapp
Interim balance after 20 months of lap-joint exposure
1999 - IRG/WP 99-20164
The application of natural resins and integrated resin systems to improve the performance of Pinus sylvestris was assessed in a lap-joint test according to DIN V ENV 12037 (1996). Lap-joints of Pinus sapwood were exposed at the test field in Hamburg (Germany) in May 1997. The treated lap-joints were assessed with regard to the performance of the resin treatments out of ground. The exposure of lap-...
M Sailer, A O Rapp, R-D Peek, A J Nurmi, E P J Beckers
Fundamentals on steam fixation of chromated wood preservatives
1988 - IRG/WP 3483
Weathering of treated wood directly after impregnation leaches up to 2% of copper-chromate-containing wood preservatives. Almost total fixation of Cr+6 is achieved by steaming the treated wood at 100°C to 120°C, preferably 110°C. To initiate such spontaneous fixation 85°C to 90°C inside the wood are essential, which requires heating times ranging from 20 to 80 min, depending on timber species...
R-D Peek, H Willeitner
Toxic values derived from EN 113 tests - are they determined by the virulence of a test fungus?
- Results from a round robin test -
1999 - IRG/WP 99-20176
The virulence of Coniophora puteana BAM Ebw. 15, the obligatory test fungus on softwood in tests according to EN 113, is known to be rather inconstant at least in some laboratories. The mass losses of untreated Scots pine sapwood blocks in an EN 113 test may range from below 20% to up to more than 50%. Possible reasons for these differences as well as the impact of a low virulence on the toxic val...
H Leithoff, R-D Peek, H V Borck, R Goettsche, H Kirk, M Grinda
Formation of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) during the combustion of impregnated wood
1995 - IRG/WP 95-50040-19
Wood waste and industrial wood residues often contain various preservatives. The waste management for these residuals can be recycling, deposition or combustion. Among the three possibilities, combustion seems to be the most efficient way of disposal. To obtain detailed information about emissions of organic compounds with environmental impact, especially polychlorinated dibenzo-p-dioxins (PCDD) a...
T Salthammer, H Klipp, R-D Peek
Growth of the copper tolerant brown rot fungus Antrodia vaillantii on different substrates
1995 - IRG/WP 95-10121
In recent years the copper tolerant brown rot fungus Antrodia vaillantii caused severe damages on impregnated wood in ground contact. The pattern of decay gave the impression that impregnated wood was even more severely attacked than unimpregnated. To investigate this question more closely laboratory tests were carried out. In a "choice test" Antrodia vaillantii grew preferably towards CC-impregna...
H Leithoff, I Stephan, M-T Lenz, R-D Peek
Utilization of coconut timber from north Sulawesi, Indonesia. Part 2: Treatability
1994 - IRG/WP 94-40025
Under tropical conditions coconut wood is quickly degraded by mold and blue stain fungi. Low density wood in ground contact is commonly decomposed by wood destroying fungi within a period of only a few months, higher density wood from the outer stem regions within 24 to 30 months (MOSTEIRO, CASIN, SERIBAN 1976; McQUIRE 1975). Moreover, according to McQUIRE (1975) green wood of lower density is hig...
R-D Peek
New principles for the protection of wood: Impregnation with waterborne resins
1995 - IRG/WP 95-40047
The environmental impact of classical wood preservatives as well as the use of tropical wood species with high natural durability is regarded increasingly critically in the public. Therefore other partially new principles for the protection of wood, like chemical modification, or treatment with resins were examined especially in USA, Japan and in Europe with promising results predominantly in the ...
A O Rapp, R-D Peek
Penetration as Key Factor for Determining the Performance of Wood Preservatives
2004 - IRG/WP 04-20293
Stakes of Scots pine sapwood with a dimension of 4 x 4 x 75 cm³ were impregnated with preservatives containing 2 % of propiconazole which had passed the EN 113 test criteria without any problems. The
penetration of the colourless preservative was determined successfully by a fungal screening test described by Sutter (1978). The test revealed the insufficient penetration behaviour within the gi...
H Leithoff, I Stephan, R-D Peek
Effects of the specimen position on fungal colonisation and wood decay by en 113 test fungi
1998 - IRG/WP 98-20136
For testing wood preservatives according to EN 113 it is common practice to plant the test blocks on neutral supports in order to prevent (1) a diffusion of chemicals into the agar medium and (2) an excessive moistening of the specimens. The procedure was employed in EN 350-1 for testing the natural durability of solid wood.
It turned out to be of problematic nature because of the individual requ...
G Kleist, M-T Lenz, R-D Peek