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This article deals with the fractionation of wood dust by sieve after sanding. Dust from untreated beechwood was compared to dust from thermally modified beechwood (at 200 °C for 3 h). The authors hypothesized that the thermal modification changes the particle size distributions of the dust sieve fractions and that all the dust sieve fractions contain the finest particles, which are suspendable in the air and are potentially respirable. To obtain dust for testing, both wood materials were sanded with P120 paper at a belt speed of 14.5 m/s and a pressure of 0.65 N/cm² . A set of sieves with aperture sizes of 25, 80, and 250 µm were used to separate the dust into sieve fractions with grain sizes less than 25 µm, 25 to 80 µm, 80 to 250 µm, and greater than 250 µm. The content of the finest particles in the fractions was measured via a laser particle sizer. Both dusts had similar particle size distributions. In addition, each investigated fraction of both dusts contained the finest particles, i.e., less than 10 µm. It follows that the laser analysis method may be necessary to correctly assess the occupational risk at a sanding. [ABSTRACT FROM AUTHOR]

The aim of the paper is to determine the granulometric composition of chip removed from the beech lumber milling process using a CNC machining center SCM Tech Z5 in the range of commonly used technical and technological parameters under standard conditions of feed speed: vf = 1 ÷ 5 m.min-1 and the thickness of the removed layer: e = 1, 3 and 5 mm. Another goal of the paper was to select a suitable separation technique that would be sufficient to effectively capture the largest possible dispersion of fractions in the beech lumber milling process. Granulometric analysis showed that under the given conditions in the milling process the largest proportion of coarse and medium coarse fraction is formed and particles with a size smaller than 32 µm are not formed. For this reason, it is our recommendation to choose a combination of dry mechanical separators together with fabric filters, as mechanical separators are able to capture mainly larger particle fractions. Fabric filters would serve to trap any finer particles, thus saving the user from greater wear of the coarse and medium coarse fractions, which would increase the wear of the filter cloth to an increased extent. [ABSTRACT FROM AUTHOR]

TechnoPORTA. Intelligent, customized technological line for the automated production of technical doors - selected technical and economic indicators. The development and implementation of innovative production of technical doors in a pilot technological line made it possible to automate the production process. It became possible to manufacture doors with dimensions and weight significantly exceeding the current technological capabilities of the company. An additional benefit resulting from the implementation of the TechnoPORTA line is the improvement of technical and economic indicators related to the consumption of basic materials, additional materials and energy. It relates to annual savings of material in the production line, the unit consumption of electricity and the unit application of the adhesive during postforming. [ABSTRACT FROM AUTHOR]

The present paper provides characteristics of three species of grain straw particles applied in the production of lignocellulose particleboards. For the sake of the investigation, rapeseed, rye, and triticale straw were fragmented to the size of particles used in the wood-based materials industry. The aim of the research was to determine physical properties of particle of rapeseed, rye, and triticale straw and to evaluate their usefulness in the process of manufacturing lignocellulose particleboards purposed for building constructions. Another aspect of the work was to determine the influence of moisture content of straw particles (using rapeseed straw as an example) on properties of the manufactured particleboards made with its use. The conclusion is that each of the investigated materials is characterized by different geometry, poured and tapped bulk density, varied angle of repose, and slippery angle of repose. Differences in sizes and shapes of particles of various grain species and in their moisture content strongly affect properties of particleboards produced with their use. The investigations prove that the best properties are observed for rye straw particleboards. However, due to their physical parameters, difficulties in storage, transport, and particleboards production may happen to be more considerable than in case of other materials. [ABSTRACT FROM AUTHOR]

Dimensional accuracy of machining translates into susceptibility to defects in assembly of furniture elements. In the initial drilling phase, the tip of the drill may slip due to the properties of the workpiece, which may result in inaccurate machining. Taking this into account, it was decided to investigate this phenomenon for drilling in the side of the plywood board. Samples for testing were made of 18 mm thick, 13 layer birch-alder plywood, covered with melamine film, glued with phenol-formaldehyde glue. With the use of an industrial dowel drilling machine, 30 holes in each of three examined layer were made. All holes were made parallel to the layers – on the side of the plywood board, and their axes were located in three adjacent layers: the birch veneer layer, the adhesive layer, and the alder veneer layer. Two types of geometric accuracy of holes were analyzed: the distance between the real center of the hole and the nominal position and also the inclination of the hole axis from the nominal axis. The holes made in the adhesive layer showed approximately twice larger deviations compared with the holes made in two adjacent layers of veneer. There was no significant relationship between the deviations of the angle of holes axis and the inaccuracies in the position of their centers. Main conclusion: When drilling in the side surface of the plywood board, less accurate holes are obtained if the hole axis is located in the adhesive layer, and there is more accuracy if the hole axis is located in the veneer layer. [ABSTRACT FROM AUTHOR]

Wood compounds, especially sterols, are connected with the level of contamination with microscopic fungi. Within this study, tests were conducted on wood dust samples collected at various work stations in a pine and birch timber conversion plant. Their contamination with mycobiota was measured as the concentration of ergosterol (ERG) by ultra performance liquid chromatography (UPLC). Another aim of this study was to assess the effect of contamination with microscopic fungi on the sterol contents in wood dusts. Analyses were conducted on five sterols: desmosterol, cholesterol, lanosterol, stigmasterol, and β-sitosterol using UPLC and their presence was confirmed using gas chromatography/mass spectrometry (GC/MS). The results of chemical analyses showed the greatest contamination with mycobiota in birch wood dust. We also observed varied contents of individual sterols depending on the wood dust type. Their highest concentration was detected in birch dust. The discriminant analysis covering all tested compounds as predictors showed complete separation of all tested wood dust types. The greatest discriminatory power was found for stigmasterol, desmosterol, and ergosterol. [ABSTRACT FROM AUTHOR]

This paper presents the results of the granulometric analysis of sawdust, created during the sawing of modified and unmodified beech wood with a circular saw. The aim of this work was to analyze the effect of the treatment of beech wood (Fagus sylvatica L.) on the content of respirable and inhalable particles in sawdust generated during the sawing process using a modern circular saw. Different methods of particle-size determination were used. The results obtained from the sieve analysis prove that the sawdust created during the cutting of DMDHEU was finer than the sawdust from native beech and other modified materials. It was also discovered that the dust created during the cutting of Bendywood was finer than when machining native beech and Lignamon. There was an increase in the share of fine fraction in the range of granularity x < 100 µm at the expense of the fraction x = 0.25-1 mm. The properties of Lignamon are primarily based on the properties of raw wood material, therefore this modified material had a similar cumulative particle-size distribution to the native beech dust. [ABSTRACT FROM AUTHOR]

The properties of particleboards and the course of their manufacturing process depend on the characteristics of wood particles, their degree of fineness, geometry, and moisture content. This research work aims to investigate the physical properties of wood particles used in the particleboard production in dependence on their moisture content. Two types of particles currently used in the production of three-layer particleboards, i.e., microparticles (MP) for the outer layers of particleboards and particles for the core layers (PCL), were used in the study. The particles with a moisture content of 0.55%, 3.5%, 7%, 10%, 15%, and 20% were tested for their poured bulk density ( ρ p ), tapped bulk density ( ρ t ), compression ratio (k), angle of repose ( α R ), and slippery angle of repose ( α s ). It was found that irrespective of the fineness of the particles, an increase in their moisture content caused an increase in the angle of repose and slippery angle of repose and an increase in poured and tapped bulk density, while for PCL, the biggest changes in bulk density occurred in the range up to 15% of moisture content, and for MP in the range above 7% of moisture content, respectively. An increase in the moisture content of PCL in the range studied results in a significant increase in the compression ratio from 47.1% to 66.7%. The compression ratio of MP increases only up to 15% of their moisture content—a change of value from 47.1% to 58.7%. [ABSTRACT FROM AUTHOR]

Camelina sativa (L.) Crantz is an oilseed relict crop. This article recognizes camelina's current and potential future uses based on a comprehensive scientific and patent document analysis. The annual number of literature on camelina increased significantly; in the case of patent documents, this increase is most evident after 2009 and in the case of scientific publications – after 2010. We identified six main thematic groups among 1039 scientific papers analyzed: cultivation, genetics, biological characteristics, livestock feeding, energetic use, and oil extraction technology. We also showed the links between these groups. There are seven vital patent applications among 2307, which meet two conditions: they are highly cited in other patent documents and submitted for protection in many global patent jurisdictions. The current scientific research on the use of camelina focuses on: animal feed, human foodstuff, industrial chemical raw materials (glycerin, polymers, ethanol, lignin), fuels (diesel, jet fuel, biogas, energy pellet, pyrolysis oil), and compost to improve soil. The results of the analysis of scientific and patent documents point to potential future applications of camelina: as a pioneer crop in reclaimed areas, as a cover or companion crop in agriculture, and as a source for new chemical additives (to pesticides, coatings, glue, and filaments in 3D printing technology), as meat analogs, as a feedstock in construction and packaging materials production, as a source of biochar and as straw water filters. • We analyzed 1039 scientific papers and more than 2300 patent Camelina sativa documents. • There are six main thematic groups among 1039 scientific documents related to Camelina sativa. • The annual number of patents and scientific literature on Camelina sativa increased rapidly after 2009. • There are opportunities to expand the field of application of Camelina sativa. [ABSTRACT FROM AUTHOR]

Wood compounds, especially sterols, are connected with the level of contamination with microscopic fungi. Within this study, tests were conducted on wood dust samples collected at various work stations in a pine and birch timber conversion plant. Their contamination with mycobiota was measured as the concentration of ergosterol (ERG) by ultra performance liquid chromatography (UPLC). Another aim of this study was to assess the effect of contamination with microscopic fungi on the sterol contents in wood dusts. Analyses were conducted on five sterols: desmosterol, cholesterol, lanosterol, stigmasterol, and β-sitosterol using UPLC and their presence was confirmed using gas chromatography/mass spectrometry (GC/MS). The results of chemical analyses showed the greatest contamination with mycobiota in birch wood dust. We also observed varied contents of individual sterols depending on the wood dust type. Their highest concentration was detected in birch dust. The discriminant analysis covering all tested compounds as predictors showed complete separation of all tested wood dust types. The greatest discriminatory power was found for stigmasterol, desmosterol, and ergosterol.

Background: Microscopic fungi are the biological agent of occupational risk in the woodworking environment. Microbiological and chemical methods were used for determination of their concentration and species composition in dust., Material and Methods: Dust was sampled in 3 factories producing furniture using different materials. The 1st factory (A) processes solid wood, the 2nd (B) - chipboards and the 3rd factory (C) uses both wood and wood composites. The samples were collected in 12 different workstations and locations in each factory. The quantitative content of fungal biomass was determined basing on analysis of ergosterol (ERG). The species composition of fungi was analyzed using the microbiological method basing on culture morphology., Results: The concentration of ergosterol was relatively low and ranged from 0.012 mg/kg to 3.36 mg/kg. The average value of ERG amounted to 1.25 mg/kg in factories A and C and 1.15 mg/kg in factory B. The most frequently isolated fungi in factory A and B were Penicillum and Aspergillus. However, in the factory C, only Trichoderma was isolated. The maximum concentration of fungi in dust collected in factory B was 2377 cfu/g and it is 3 times more than in the dust from factories A and C., Conclusions: Workers of furniture factories may be exposed to airborne fungi associated with the wood dust posing health hazard. The content of these fungi is relatively small (ERG - max: 3.36 mg/kg) but the species, especially genera Penicillum and Aspergillus, found in the dust which were reported as having allergic and toxic properties.