Properties of biomass obtained from short-rotation inger willow clone grown on a contaminated and non-contaminated land

The paper aims to analyze the biomass at one year growth, resulting from the cultivation of the INGER energy willow clone as a short rotation crop (SRC), in order to use it as a renewable fuel. The paper completes the data in the field of renewable energies in the context of decreasing fossil energy reserves worldwide and emphasizing the impact on renewable energies. The effect of a contaminated land on the survival rate of the planted seedlings and the effect of the energy willow culture on the composition of the contaminated soil are analyzed. The obtained results show that the biomass characteristics, such as the calorific power of about 18,21 kJ/g to18,90 kJ/g, and the ash content of about 2,25 %, are comparable with the ones of other lignocellulosic energy materials. The results found in this studyshowed that the woody biomass in the first vegetation year of energy willow can be used directly as a renewable fuel without the need for compaction in the form of briquettes or pellets

The Effect of Veneer Densification Temperature and Wood Species on the Plywood Properties Made from Alternate Layers of Densified and Non-Densified Veneers

In this study the properties of plywood manufactured from densified and non-densified veneer sheets and alternate layers of such veneers with and without densification using low amount of adhesive as a function of densification temperature and wood species were investigated. The plywood panels were made from rotary-cut birch and black alder veneers using urea-formaldehyde (UF) adhesive. Veneer sheets with thickness of 1.5 mm were subjected to the thermal-compression at three different temperatures while keeping constant the pressure during a same time span. Five-layers plywood panels were produced using a constant hot-pressing schedule using different amounts of glue spread as a function of the plywood type; such as plywood made from non-densified (80 g/m2) and densified (60 g/m2) veneers only; and combination of them (70 g/m2). The bending strength (MOR) and the modulus of elasticity (MOE) along with the shear strength of the plywood samples for bonding class 1 (dry conditions) have been determined. As expected bending strength of the plywood samples increased with the increasing in density. The increase of veneer densification temperature resulted in a gradually decrease of MOR; MOE and shear strength values for the plywood panels made of densified veneers and mixed panels of both species. The temperature of 150 °C for veneer densification seemed to be enough to achieve enhanced bending and bonding properties. All plywood panels in this study were manufactured using reduced glue consumption and they presented satisfactory properties performance for indoor applications

Evaluation of Selected Properties of Alder Wood as Functions of Sanding and Coating

The objective of this study was to optimize the sanding and coating processes of black alder wood to promote and support its use in furniture manufacturing. Two criteria have been applied for process optimization, namely, the minimum surface roughness of the samples and power consumption during sanding as a function of various sanding systems. The surface roughness of the sanded specimens and the power consumption during sanding strongly depends on the grit size used. Two eco-varnishes were applied to the samples by spraying. Moreover, the effect of the surface preparation and varnish type on the coating properties expressed by the varnish layer adherence to the substrate and surface glossiness was evaluated. For better glossiness values, the UV-cured varnish was preferred. The sanding with a grit sequence of 60, 120, and 150 grit size abrasives was found to be optimal when applied to black alder wood, and it is recommended to obtain performant UV-coated wood surfaces for furniture products

Colour Changes Evaluation of Freshly Cut Alder Veneers Under the Influence of Indoor Sunlight

The paper presents an experimental study concerning the colour changes occurred on the surfaces ofblack alder veneers (Alnus glutinosa), obtained from a freshly cut (not treated) log, after their exposure tosunlight and darkness, for 1 and 3 months, under indoor conditions.A Chroma Meter Konika Minolta CR-410 device was used for colour measurement.The colorimetric coordinates were recorded before and after the exposure, according to ISO 7724-2.The results highlight a significant decrease of colour lightness, right after the first month of sunlight exposure.The a* and b* colour coordinates showed an increasing tendency with increasing exposure time, whichsignifies a colour darkening under sunlight radiation that penetrates the window glass. Colour differenceswere noticed right after the first month of sunlight exposure, while under darkness conditions, a relativecolour constancy was noticed, the colour changes being less pronounced, but yet perceptible by the humaneye.The study results complete the colorimetric database of veneers used in furniture industry, but theyalso contribute to the rehabilitation of black alder as a wood species with a real potential of use in furnitureindustry

OPTIMIZATION OF WOOD MILLING SCHEDULE – A CASE STUDY

The paper presents the results of a case study applied to the milling process of solid wood specimens made of black alder wood (Alnus glutinosa L. Gaertn.) with a view to find the optimal cutting schedule when two main criteria, such as the minimum power consumption and the best surface quality are fulfilled.The experimental work was performed with black alder wood originating from mature trees from the Buzau Valley region in Romania. All samples were processed on their longitudinal edges by straight milling with a milling cutter having glued straight plates on the vertical milling machine under different cutting schedules. An electronic device connected to the machine engine and an acquisition board were used to record and compute the power consumption during milling. Roughness measurements of the samples were performed by employing an optical profilometer. All data were processed using the regression method and variance analysis. The study revealed that best results are to be obtained in terms of cutting power and surface quality when processing with low feed speeds and light cutting depths

ANALYSIS OF SURFACE ROUGHNESS OF BLACK ALDER AS FUNCTION OF VARIOUS PROCESSING PARAMETERS

The objective of this study was to analyse thesurface quality of black alder (Alnus glutinosa)samples as function of sanding processes based onfour grits sizes, namely 60, 80, 100 and 120. Thesanding process was performed parallel,perpendicular and at 45 degrees angle to the grainorientation of the specimens. The experiments werecarried out on a wide belt sanding machine atNIKMOB Nehoiu Company. Two machiningvariables, feed speed and cutting depth were usedfor the tests. Two roughness parameters, Rk(processing roughness parameter) and Rpk (fuzzygrain roughness parameter) were determined byemploying the optical profilometer type MicroProfFRT, on dry and wett areas of the samples. All datawere processed by using a nonlinear regressionmethod respecting an equation of 2nd degree typewith two variables. The ANOVA analysis was alsoused to evaluate the data by applying fiveindependent variables, namely: sanding program,sanding direction, feed speed and cutting depth forthe two statement of surface, with and withoutwetting. The results of the study revealed that thewetting of samples did not show a better quality ofsanded surfaces. However when the samples weresanded at 45 degrees angle and parallel to the grainorientation, overall surface quality of the samplesimproved compared to perpendicular direction. It wasalso found that the cumulative effect of factors wasmore representative on the roughness parametersthan the situation when taken individually. It appearsthat based on the findings in this work suchapproach can be successfully applied in woodproducts industry including furniture manufacturing tohave a more efficient use of the raw material infurther processing steps such as finishing

Evaluation of Selected Properties of Alder Wood as Functions of Sanding and Coating

The objective of this study was to optimize the sanding and coating processes of black alder wood to promote and support its use in furniture manufacturing. Two criteria have been applied for process optimization, namely, the minimum surface roughness of the samples and power consumption during sanding as a function of various sanding systems. The surface roughness of the sanded specimens and the power consumption during sanding strongly depends on the grit size used. Two eco-varnishes were applied to the samples by spraying. Moreover, the effect of the surface preparation and varnish type on the coating properties expressed by the varnish layer adherence to the substrate and surface glossiness was evaluated. For better glossiness values, the UV-cured varnish was preferred. The sanding with a grit sequence of 60, 120, and 150 grit size abrasives was found to be optimal when applied to black alder wood, and it is recommended to obtain performant UV-coated wood surfaces for furniture products

Some Technological Properties of Plywood after Fire Retardant Treatment in Different Concentrations

The treatment with fire retardant chemicals is the most effective process to protect wood and wood based products from fire. Therefore, use of fire retardant chemicals has been increased. However, the fire retardant chemicals have an effect on other physical, mechanical and some technological properties of the materials treated with them. In this study the effect of various fire retardant chemicals in different concentrations on the technological properties of plywood were examined. Poplar (Populus deltoides) and scots pine (Pinus sylvestris L.) were used as wood species; zinc borate, monoammonium phosphate (MAP) and ammonium sulfate were used as fire retardant chemicals and UF resin was used as adhesive. The veneer sheets were treated by immersion and three different concentrations, such as 5%, 7% and 10% aqueous solutions were selected. Mechanical properties of plywood panels, such as the shear strength, bending strength and the modulus of elasticity were determined according to EN 314-1, EN 310, respectively. The surface roughness of the veneer sheets was determined according to DIN 4768 standard. As a result of this study, it was found that all the mechanical strength values of panels produced by using the veneers treated with fire retardant chemicals were lower than those of control panels. With the increasing of the solution concentration their values decreased while the surface roughness values increased

Glossiness Evaluation of Coated Wood Surfaces as Function of Varnish Type and Exposure to Different Conditions

The objective of this study was to evaluate the glossiness of black alder wood (Alnus glutinosa L.) samples coated with two varnish types as a function of exposure to dry heat and artificial aging. The chemical resistance of the coated samples to cold liquids was also evaluated. Based on the findings in this work, it appears that the varnish types and their structural differences influenced the overall glossiness of the coated samples. The UV varnish exhibited higher gloss values than those coated with the water-borne product within the range of silky gloss and silky matte grades. The heat exposure influenced the surface glossiness of the UV-coated samples more than the samples coated with water-borne varnish. The overall gloss values of the samples decreased with the exposure time to artificial aging, resulting in no layer cracks. The cold household liquids left less visible traces on the surfaces and alcohol was found to be the strongest agent. This study could have practical applications in the furniture industry to produce value-added furniture units according to their specific conditions of indoor use

Properties of biomass obtained from short-rotation inger willow clone grown on a contaminated and non-contaminated land

The paper aims to analyze the biomass at one year growth, resulting from the cultivation of the INGER energy willow clone as a short rotation crop (SRC), in order to use it as a renewable fuel. The paper completes the data in the field of renewable energies in the context of decreasing fossil energy reserves worldwide and emphasizing the impact on renewable energies. The effect of a contaminated land on the survival rate of the planted seedlings and the effect of the energy willow culture on the composition of the contaminated soil are analyzed. The obtained results show that the biomass characteristics, such as the calorific power of about 18,21 kJ/g to18,90 kJ/g, and the ash content of about 2,25 %, are comparable with the ones of other lignocellulosic energy materials. The results found in this studyshowed that the woody biomass in the first vegetation year of energy willow can be used directly as a renewable fuel without the need for compaction in the form of briquettes or pellet