SOFTWOOD COMPOSITES FOR CONSTRUCTION

2021 ◽  
Author(s):  
A.A. Lukash ◽  
◽  
N.P. Lukuttsova ◽  
K.P. Kolotvin ◽  
K.V. Razrezov ◽  
...  
Keyword(s):  
Industrial Waste ◽  
Building Materials ◽  
Urea Formaldehyde ◽  
Negative Influence ◽  
Water Soluble ◽  
Winter Period ◽  
Composite Manufacturing ◽  
Secondary Use ◽  
Wood Consumption ◽  
Manufacturing Mode

The article deals with the issues of secondary use of industrial waste from the processing of soft hardwood wood. It is shown that the disposal of man-made waste in landfills is undesirable, and the use of wood waste to generate heat for heating is limited to the autumn-winter period. It is proved that it is most expedient to make composites from the waste of processing soft hardwood wood, since the need for inexpensive building materials is constantly increasing. Wood- cement materials from soft-leaved wood are practically not produced due to the presence of water- soluble saccharides, which worsen the process of hydration of cement. It is proposed to use binders that harden quickly in the production of composites made of soft hardwood. To exclude the negative influence of the extracted substances, it is proposed to use urea-formaldehyde glue as a binder. The mathematical dependence of the compressive strength of a composite made of soft hardwood on the glue consumption, wood consumption and the duration of exposure after molding is obtained. The parameters of the composite manufacturing mode are set: wood consumption-190 ... 195 kg/m3, urea-formaldehyde glue consumption-262...270 kg/m3; the duration of exposure after molding – 6 days. Methods for reducing the release of free formaldehyde from composites have been identified. It was found that in the steam-air mixture after 12 days of exposure of the chip-and- glue composite, there are no previously detected micro-impurities of formaldehyde, and the chip- and-glue composite can be used in construction without restrictions.

scholarly journals FEATURES OF USE OF INDUSTRIAL TECHNOGENIC WASTE IN THE FIELD OF BUILDING MATERIALS

2021 ◽  
Vol 29 (2) ◽  
pp. 24-34
Author(s):  
M. Lemeshev ◽  
◽  
K. Sivak ◽  
M. Stadniychuk ◽  
◽  
...  
Keyword(s):  
Industrial Waste ◽  
Large Scale ◽  
Building Materials ◽  
Water Soluble ◽  
Additional Energy ◽  
Construction Products ◽  
Efficient Construction ◽  
Method Of Production ◽  
Reduced Rate ◽  
Choice Of Technology

Another aggravation of the ecological and economic situation in Ukraine makes it necessary to develop new efficient technologies for processing and use of industrial man-made waste from the heat and chemical industries. Such technologies should ensure their maximum degree of use in the production of high-quality efficient construction products. The choice of technology for the preparation, processing and use of industrial waste depends on such factors as their chemical-mineralogical and particle size distribution and method of production. Although such wastes are mostly used as aggregates, their overall use remains low. The share of their use in the manufacture of construction products is 5-12%, and the manufacture of products requires additional energy consumption. The paper considers the possibility of using industrial waste not only due to their activation, but also due to the use of their multifunctional properties. When the inactivated ash is introduced into the concrete mixture, it increases the plasticity of such a mixture and at the same time the microfiller promotes the formation of a stronger contact zone by increasing the degree of crystal chemical similarity of tumors. Excessive amounts of ash in ash-containing materials lead to increased porosity and reduced rate of accumulation of strength over time, which impairs performance, including frost and corrosion resistance. Large-scale use of phosphogypsum is hindered by its specific features: physical state, high humidity, the presence of phosphoric and sulfuric acid and water-soluble harmful compounds of phosphorus and fluorine. Therefore, before using phosphogypsum, it is necessary to remove or neutralize harmful impurities and reduce the concentration of acid residues. Harmful impurities can be bound and acid residues can be neutralized by adding quicklime to the solution. Lime simultaneously neutralizes acids and binds water-soluble harmful impurities. The most effective method of using phosphogypsum, fly ash and fine powders of steel sludge SHH-15 is the integrated use of such waste, resulting in a complex metal-ash-phosphate binder (MАРВ).

Comprehensive Characterization of Agricultural By-Products for Bio-Aggregate Based Concrete

2022 ◽  
Author(s):  
Herinjaka Haga Ratsimbazafy ◽  
Aurélie Laborel-Préneron ◽  
Camille Magniont ◽  
Philippe Evon
Keyword(s):  
Water Absorption ◽  
Building Materials ◽  
Complete Characterization ◽  
Water Soluble ◽  
Dry Density ◽  
Characterization Methods ◽  
Manufacturing Method ◽  
West Part ◽  
Hemp Shiv ◽  
By Products

The valorization of available agricultural by-products is important for the development of bio-aggregate based concretes as eco-friendly solutions for building materials. However, their diversity requires to assess their potential of use in vegetal concretes. This study aims to propose simple and relevant multi-physical characterization methods for plant aggregates. Basic and complementary characterizations were carried out on hemp shiv as a reference plant aggregate, and nine by-products available in the South-West part of France, i.e., oleaginous flax shiv, sunflower pith and bark, coriander straw, wheat straw, wheat chaff, corn shuck, miscanthus stem and vine shoot. The basic characterizations performed were those recommended by the TC-RILEM 236 BBM, i.e., particle size distribution, bulk density, water absorption and thermal conductivity. Complementary characterizations have also been proposed, taking into account the possible environment of the binder and the vegetal concrete manufacturing method. The additional tests developed or adapted from previous research assess the following properties: the content of water-soluble compounds at pH 7 and 12, the dry density of plant aggregates compacted in wet state, the real water absorption after compaction and the compression behavior of these compacted aggregates. This complete characterization highlights the distinct behavior of the different agroresources and allows to correlate these characteristics to the use properties of hardened composites.

Interfacial interactions between urea formaldehyde and cellulose nanofibrils (CNFs) of varying chemical composition and their impact on particle boards manufacture (PBs)

2021 ◽  
Author(s):  
Maria C. Iglesias ◽  
Philip S. McMichael ◽  
Osei A. Asafu-Adjaye ◽  
Brian K. Via ◽  
Maria S. Peresin
Keyword(s):  
Chemical Composition ◽  
Building Materials ◽  
Colloidal Stability ◽  
Low Cost ◽  
Urea Formaldehyde ◽  
Cellulose Nanofibrils ◽  
Global Market ◽  
Modulus Of Rupture ◽  
Superior Performance ◽  
Interfacial Interactions

Abstract Wood-based panels are commonly used as building materials for interior and exterior purposes. Their production and utilization have increased over the past decades due to the useful properties they present. Adhesive-bonded products make up to 80% of the wood alternatives on the global market, and of that, urea-formaldehyde (UF) makes up approximately 81% of the resins used. Formaldehyde-based resins are used due to their effectiveness and low cost, as well as their ease of application and lack of color. Nevertheless, their main disadvantages are the lack of tackiness and the emission of formaldehyde over time. To improve UF performance, the utilization of microfibrillated cellulose, has been demonstrated to be effective. However, more understanding on the mechanisms of the interactions is of relevant importance. In this work, we studied interfacial interactions between UF with bleached (BCNF) and unbleached (LCNF) cellulose nanofibrils using Quartz Crystal Microbalance with dissipation monitoring (QCM-D) technique observing the superior performance of lignin-containing CNF. Additionally, the surface free energies were investigated using Contact Angle Measurements (CA) showing a decrease of the values mainly when utilizing LCNF, which was later correlated with the wettability properties of the particle boards (PBs). PBs with different adhesive/CNF formulations were produced showing larger improvements when adding LCNF in terms of modulus of elasticity (MOE), modulus of rupture (MOR), and internal bonding (IB). To gain a better understanding on the interactions between CNF and UF, CNF was fully characterized in terms of morphology, chemical composition, charge density, as well as thermal and colloidal stability.

The Application of Industrial Waste in Landscaping

2013 ◽  
Vol 361-363 ◽  
pp. 740-746
Author(s):  
Yi Jie Liu ◽  
Shu Zhang
Keyword(s):  
Solid Waste ◽  
Industrial Waste ◽  
Building Materials ◽  
Waste Recycling ◽  
Environment Protection ◽  
Project Cost ◽  
Landscape Architect ◽  
Main Emphasis ◽  
Modern Landscape

This thesis put the main emphasis on how to utilize the solid waste, that is the offscum, to apply into landscaping after reprocessing. This thesis starts form discussing the building materials in landscaping and the specialness of construction, then tries to analyze the structure of every element in landscape construction, tries to select the industrial waste that can be applied into landscape construction from numerous industrial waste recycling products, and give a brief introduction of its mechanism and method. Besides, this thesis calls on modern landscape architect to actively utilize the waste to construct landscape, for not only lower project cost, but also more environment protection. Keywords: industrial waste; landscape; utilize, environment

scholarly journals Characteristics and Seasonal Variations of Atmospheric Deposition of Selected Elements in the Urban and Industrial Environment of Košice (Slovakia)

2021 ◽  
Vol 906 (1) ◽  
pp. 012100
Author(s):  
Jozef Hančul’ák ◽  
Ol’ga Šestinová ◽  
Lenka Findoráková
Keyword(s):  
Atmospheric Deposition ◽  
Detailed Analysis ◽  
Pearson Correlation ◽  
Correlation Coefficients ◽  
Water Soluble ◽  
Dust Particles ◽  
Winter Period ◽  
Emission Sources ◽  
Summer Period ◽  
The Impact

Abstract This study aims to evaluate the impact of local emission sources on the environmental load through a detailed analysis of the atmospheric deposition (AD). The main sources of pollution are neighbouring iron and steelworks and typical urban sources, such as the heating plant, transport, construction, etc. Total atmospheric deposition, i.e. both wet and dry ones, were sampled from eleven sampling sites that have been placed on the roofs above the height of the surrounding buildings at a distance of 1 to 16 kilometers from the main source of pollution in the urban, suburban and rural areas. The atmospheric deposition fluxes of selected elements (Fe, Al, Mn, Zn, Pb, Cu, Cr, Cd, As) were determined separately for “water-soluble” and “insoluble phase” (particulate matter - PM) as well as in terms of the heating season for summer and winter half-year. The results from 2009–2020 are introduced. The average Fe deposition at urban stations in Košice was 2-3 times higher, compared with other urban areas. The very high values of iron deposition (9,181) and manganese (348 mg.m-2.yr-1) were measured mainly at sites near the ironworks. The highest values of correlation coefficients were calculated by Pearson correlation analysis for the elements Fe, Mn and Cr but also for Al and PM. Higher values of correlation coefficients were calculated for the winter period. The monitored elements are bound to the insoluble component AD in the order of Fe, Al, Cr, Pb, Mn and As. Cadmium and zinc are preferably bound to the soluble phase for sites north of the ironworks. Significant differences for fluxes of AD of the most observed parameters were found between the summer and winter periods. In winter, higher values of AD were found for the elements Fe, Pb, Mn, Cr, and Cd. In the case of zinc and arsenic higher values were recorded in the summer period. The share of emission sources of iron and steelworks on the fluxes of iron at the urban sites in winter was more than doubled compared to the summer period. The smallest seasonal differences for all observed components were found at localities near the ironworks. Detailed analysis of AD showed that in addition to Fe, Mn, and Cr, the ironworks complex is also a source of dust particles, aluminum and other observed elements in descending order of lead, zinc, copper, arsenic and cadmium.

scholarly journals EFFECT OF PVA MODIFICATION ON PROPERTIES OF CEMENT COMPOSITES

2015 ◽  
Vol 55 (1) ◽  
pp. 64-75 ◽  
Author(s):  
Jaroslav Topič ◽  
Zdeněk Prošek ◽  
Kateřina Indrová ◽  
Tomáš Plachý ◽  
Václav Nežerka ◽  
...  
Keyword(s):  
Cement Paste ◽  
Building Materials ◽  
Bending Strength ◽  
Strength Reduction ◽  
Water Soluble ◽  
Cement Composites ◽  
Polymer Modification ◽  
Entire Volume ◽  
Water Soluble Polymers ◽  
Soluble Polymers

Polymers are used for modification of the cement-based composites and others building materials since the thirties of 20th century. Based on the conclusions of recent studies, it is assumed that even water soluble polymers could be used as an admixture for such modification. Currently, there exist and are exploited several possibilities for polymer modification of mortars, wood-based products or bituminous asphalts. Various options differ in the way of modification, which can be basically applied to the entire volume or just a surface, but also in the form of the polymer used – either in the form of solution or fibers. The aim of our study was to investigate the influence of volume modification by the water soluble polymers, such as polyvinyl alcohol (PVA), on the properties of cement paste and find an optimum additive. It turned out that the addition of PVA solution into fresh cement paste results in an increase of porosity and therefore a stiffness and compressive strength reduction. On the other hand, the bending strength of PVA-rich specimens was significantly higher and their water absorption decreased, which may consequently result in enhanced frost resistance.

The Role of Industrial Waste in the Formation of the Structure and Properties of Effective Wall Ceramics

2018 ◽  
Vol 931 ◽  
pp. 578-582
Author(s):  
Natalia D. Yatsenko ◽  
N.A. Vil'bitskaya ◽  
A.I. Yatsenko
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Industrial Waste ◽  
Building Materials ◽  
Raw Materials ◽  
Industrial Wastes ◽  
Structure And Properties ◽  
Innovative Technologies ◽  
Furnace Slag

The article deals with the use of blast furnace slag and mineralising additives as raw materials for the production of building materials. Innovative technologies of brick production from natural raw materials and industrial wastes are developed.

scholarly journals Fossil and non-fossil sources of organic carbon (OC) and elemental carbon (EC) in Göteborg, Sweden

2009 ◽  
Vol 9 (5) ◽  
pp. 1521-1535 ◽  
Author(s):  
S. Szidat ◽  
M. Ruff ◽  
N. Perron ◽  
L. Wacker ◽  
H.-A. Synal ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Elemental Carbon ◽  
Latin Hypercube Sampling ◽  
Water Soluble ◽  
Total Carbon ◽  
Rural Site ◽  
Urban Site ◽  
Winter Period ◽  
Back Trajectories ◽  
Wood Burning

Abstract. Particulate matter was collected at an urban site in Göteborg (Sweden) in February/March 2005 and in June/July 2006. Additional samples were collected at a rural site for the winter period. Total carbon (TC) concentrations were 2.1–3.6 μg m−3, 1.8–1.9 μg m−3, and 2.2–3.0 μg m−3 for urban/winter, rural/winter, and urban/summer conditions, respectively. Elemental carbon (EC), organic carbon (OC), water-insoluble OC (WINSOC), and water-soluble OC (WSOC) were analyzed for 14C in order to distinguish fossil from non-fossil emissions. As wood burning is the single major source of non-fossil EC, its contribution can be quantified directly. For non-fossil OC, the wood-burning fraction was determined independently by levoglucosan and 14C analysis and combined using Latin-hypercube sampling (LHS). For the winter period, the relative contribution of EC from wood burning to the total EC was >3 times higher at the rural site compared to the urban site, whereas the absolute concentrations of EC from wood burning were elevated only moderately at the rural compared to the urban site. Thus, the urban site is substantially more influenced by fossil EC emissions. For summer, biogenic emissions dominated OC concentrations most likely due to secondary organic aerosol (SOA) formation. During both seasons, a more pronounced fossil signal was observed for Göteborg than has previously been reported for Zurich, Switzerland. Analysis of air mass origin using back trajectories suggests that the fossil impact was larger when local sources dominated, whereas long-range transport caused an enhanced non-fossil signal. In comparison to other European locations, concentrations of levoglucosan and other monosaccharide anhydrides were low for the urban and the rural site in the area of Göteborg during winter.

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