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Objective. This study provides a review of organic additives, organic and inorganic binders, including air and hydraulic lime binders. Heat and mass transfer in the processes of decarbonization and carbonization of air and hydraulic lime binders and repair and restoration compositions based on them is considered, knowledge of which is necessary for the design of equipment and technological processes for the production of mineral binders, as well as technologies and compositions for repair and restoration work. Method. The dissociation and decarbonization reactions are given as reversible reactions, the decomposition front, the boundaries of limestone decomposition, the dissociation time and the dissociation reaction rate are calculated. To obtain complete information on mass transfer during the decarbonization of limestone, heat transfer is also taken into account, which complicates the task due to the nonisothermal temperature field, which affects the difference in the rates of the decarbonization reaction. Result. The solution of the problem, carried out by Held and Ivanov, and the Fourier differential equation of thermal conductivity are given. The types of lime hardening are considered: carbonate, hydrate and hydrosilicate. Carbonate hardening of lime is presented as a hardening process that takes a long time. The mechanism of carbonate hardening has been studied. The dependence of carbonization intensity on water content and humidity was revealed. Conclusion. The scientific and practical value of a new scientific direction has been established: “Research of air and hydraulic lime binders and the development of repair and restoration compositions based on them.” As a result of the research, new compositions have been developed for the repair, restoration and restoration of historical and cultural monuments that meet the repair and restoration requirements.

This article presents the results of a study on the development of an anti-corrosion plaster composite based on water glass with increased electrical conductivity. Known acid-resistant quartz-fluorosilicate composites containing liquid sodium silicate, sodium fluorosilicate and acid-resistant high-silica filler in the form of quartz, andesite or diabase powder were chosen as the prototype. The low water resistance and low adhesion to Portland cement concrete of these composites limits their application. By adding granulated blast-furnace slag to the composite, it was possible to increase the water resistance of the solution and its adhesion to concrete. The addition of graphite filler to the composite made it possible to increase the electrical conductivity. This made it possible to obtain not only a corrosion-resistant (to chemical and physico-chemical corrosion) composite, but also to use it as a grounded protective screen to drain leakage currents from the structure, thus protecting it from both corrosion and electrocorrosion destruction. [ABSTRACT FROM AUTHOR]

Environmentally friendly plywood panels were produced by a hot-pressing process using magnesium oxychloride cement (MOC) as a no-added formaldehyde adhesive. Magnesium oxychloride cement binders were prepared with different molar ratios of MgO:MgCl2 (M/C) and H2O:MgCl2 (W/C) ranging from 6 to 12 and 15 to 21, respectively, for plywood production. The binder properties measured were gel time, differential scanning calorimetry (DSC) and Fourier transom infrared spectroscopy (FTIR). The quality of the plywood panels was analyzed based on their mechanical (shear and bending) and physical (thickness swelling and water absorption) properties. A positive effect on the properties of the MOC binder as well as on the properties of the plywood was observed by increasing the molar ratio M/C up to a value of 9. The shear and flexural properties of the plywood specimens were negatively affected by further increasing the molar ratio M/C to 12 and the molar ratio W/C from 15 to 21. Differential scanning calorimetry analysis showed a peak temperature of less than 100 °C for MOC curing, which meets the requirements of hot press technology. No delamination of the plywood specimens was observed after 24 h immersion in tap water or 6 h immersion in boiling water and after a cyclic delamination test. In general, mineral-bonded plywood with magnesium oxychloride shows promising properties for indoor and outdoor use, although the binder quality should still be improved. [ABSTRACT FROM AUTHOR]

The possibility of manufacturing a mineral binder using large-tonnage waste from other industries has been studied. The object of the research are mixtures for the manufacture of cement clinker based on systems of chalk – clay – scope of paper production and chalk – clay – husks of rice processing. At the same time, urgent tasks of developing the raw material base for cement production and resource conservation were solved. The development of new initial mixtures was carried out taking into account the peculiarities of the chemical and mineralogical composition of varieties of technogenic raw materials. According to the chemical composition, rice alkali is characterized by a content of 15.6 wt. % SiO2 with a large quantitative ratio of SiO2:Al2O3 = 65.2 and a small amount of alkaline earth and alkaline oxides. Scop differs from alkali in a large amount of CaO (25.8 wt. %), a lower content of SiO2 at a quantitative ratio of SiO2:Al2O3 = 1.3. In this case, there are quantitative ratios of oxides CaO:SiO2 = 2.5, CaO:Al2O3 = 3.3, CaO:SiO2:Al2O3 = 3.3:1.4:1, which determine the probable phase transformations during firing. The main rock-forming mineral in rice husks is amorphous silica; Scope is marked by the presence of crystalline phases of calcite, quartz, and kaolinite. The analysis of the possible content of the studied wastes and the determination of the compositions of the raw mixtures were carried out using the computer program «Clinker». Analysis of computer calculations and experiments indicates the possibility of reducing by 11–16 wt. % consumption of natural raw materials in the composition of mixtures for the manufacture of clinker in comparison with the known production composition. According to X-ray phase analysis, the features of the development of crystalline phases during the firing of mixtures using varieties of technogenic raw materials at a maximum temperature of 1400 °С were established. Based on the data of technological testing, the differences in indicators of binding properties were determined – the setting time of cement when used in the composition of raw mixtures of rice husk and paper scope. [ABSTRACT FROM AUTHOR]

Abstract This study was conducted to evaluate the properties of cement-bonded composite (CBC) manufactured using jute stick particles and expanded polystyrene (EPS) beads to reduce the density of CBC for mitigating the main limitation of CBC in its applications. The CBCs were manufactured by using cement, jute stick particle, EPS and jute fiber by cold pressing having the pressure of 5 MPa and pressing time of 24 h. CBCs were also manufactured by replacing the jute stick particles with EPS beads, the processing conditions remaining the same. There were at least 5 replications for each type of board. Waste jute fibers were added for improving the degenerated mechanical properties of CBC caused by the addition of EPS beads. Important physical properties, i.e., density, water absorption (WA) and thickness swelling (TS) and mechanical properties, i.e., modulus of elasticity (MOE) and modulus of rupture (MOR) of the manufactured CBCs were tested following the Malaysian Standards. Higher percentage of EPS beads significantly reduced the density of CBCs and the lowest density (0.91 ± 0.02 g/cm3) was found when the EPS beads replaced 30% jute stick particles. As expected, mechanical properties decreased with the gradual replacement of jute stick particles by EPS beads. However, the degraded mechanical properties significantly increased when waste jute fibers were added in the CBCs. Addition of EPS beads in CBCs reduced the density, which might increase the potentiality for the utilization of cement-bonded composites for various applications.

The objective of this study is to manufacture a new geopolymer binder from pharmaceutical glass waste as a main raw material. The geopolymer synthesis followed a chemical procedure whereby the effect of several parameters, namely, the glass particle size, the concentration of the alkaline solution and the cure temperature were optimized. Several techniques were used to characterize the raw material and the obtained geopolymers: X-ray diffraction, X-ray fluorescence, Fourier-transform infrared, scanning electron microscopy and thermo-gravimetric analysis. The compressive strength of the produced geopolymers was determined by mechanical tests. The results show that the pharmaceutical glass waste produces geopolymer binder of high mechanical performance. Contrary to metakaolin-based geopolymers, no sodium silicate is required for the setting and hardening of this geopolymer type. The thermal activation by increasing the cure temperature improves the geopolymerization kinetics and leads to a high compressive strength, which exceeds 60 MPa for 60 °C and NaOH alkaline solution molarity of 8 M. [ABSTRACT FROM AUTHOR]

Finding formula for calculating the average density takes into account the density of the material between the pore walls. Researchlimitations/implications:The calculation of the fractal dimension is one of the main factors affecting the practical application of the theory of fractals, a natural problem arises on a theoretical basis to justify these calculations. Practical implications The formulas proposed in this work for calculating the fractal dimension and density of a highly porous structure improve research on methods for producing substances with a controlled fractal structure, which will help create materials with unusual mechanical properties, density, and porosity. Originality/value:The formula for calculating the fractal dimension obtained in the work improves the well-known Hausdorff- Bezikovich formula. On the other hand, it makes it possible to obtain a highly porous structure with a given density of the material under study. [ABSTRACT FROM AUTHOR]

Environmentally friendly and formaldehyde-free laminated veneer lumber (LVL) was manufactured using geopolymer constituents as binder. The main aim of the study was to improve the bonding quality between the geopolymer binder and the wood constituents. To this end, the effect of various additives (phenol flakes, conventional silica fume, and grafted silica fume with 3-aminopropyltriethoxysilane (APTES)) in the geopolymer binder features were explored via gel time and viscosity measurements, differential scanning calorimetry (DSC), and Fourier transom infrared spectroscopy. The mechanical properties (shear, bending, and compression) of LVL panels were also determined. Results showed that adding both types of silica fume had a positive impact on the geopolymer binder features. The formation of an alkaline aluminosilicate network was proven by observing the characteristics peaks of geopolymer binder at about 683 and 970 cm-1. A peak temperature of about 98 °C was determined for the geopolymer binder curing via DSC analysis. The mechanical properties were the highest for LVL panels made of geopolymer binder with grafted silica fume. It is feasible that the APTES used as grafting agent created a better bonding mechanism with superficial wood cells. In summary, the produced LVL panel showed good properties, but it still needs to be further improved to reach the required levels for use in interior and humid application. [ABSTRACT FROM AUTHOR]

Environmentally friendly and formaldehyde-free laminated veneer lumber (LVL) was manufactured using geopolymer constituents as binder. The main aim of the study was to improve the bonding quality between the geopolymer binder and the wood constituents. To this end, the effect of various additives (phenol flakes, conventional silica fume, and grafted silica fume with 3-aminopropyltriethoxysilane (APTES)) in the geopolymer binder features were explored via gel time and viscosity measurements, differential scanning calorimetry (DSC), and Fourier transom infrared spectroscopy. The mechanical properties (shear, bending, and compression) of LVL panels were also determined. Results showed that adding both types of silica fume had a positive impact on the geopolymer binder features. The formation of an alkaline aluminosilicate network was proven by observing the characteristics peaks of geopolymer binder at about 683 and 970 cm−1. A peak temperature of about 98 °C was determined for the geopolymer binder curing via DSC analysis. The mechanical properties were the highest for LVL panels made of geopolymer binder with grafted silica fume. It is feasible that the APTES used as grafting agent created a better bonding mechanism with superficial wood cells. In summary, the produced LVL panel showed good properties, but it still needs to be further improved to reach the required levels for use in interior and humid application.

Introduction. Requirements for mineral based plasters are divided into two groups: technological and performance properties. Plasticity and ease of application are attributed to the technological properties. This determines the requirements for rheological characteristics and, first of all, for the thixotropy of mixtures. The technique is developed and tested on plaster compositions based on clay-gypsum binder which belongs to the category of local binders. Russia has significant reserves of this raw material, but at present it is not used industrially. The main reason is the lack of a scientifically based theory of hardening of the clay-gypsum binder and the formation of its properties without and with modifying additives. The purpose of this research is to develop the composition and technology of application of interior plaster compositions based on stabilized binder. The methodology of studying the rheological properties of dry plaster mixtures based on clay gypsum for interior work and wet rooms is presented. The study of the rheology of clay gypsum mixtures is carried out for the first time, it determines scientific novelty. Recommendations for the use of clay gypsum plaster mixtures determine the practical significance of the research. Materials and methods. Methods of evaluation of thixotropic properties of plaster mixtures based on clay-gypsum binder in laboratory environment are realized. Results. The valid intervals of the water-cement ratio are established which ranged from 0.46 to 0.50, determined by the limiting shear stress and the actual sliding from the vertical wall. Conclusions. The possibility of using a clay-gypsum binder in dry plaster mixtures for interior decorative works in the premises, in particular, confirmed by research. It allows us to assess the actual adhesion of plaster coatings to the concrete based surfaces and to brickwork.

Refining slag used in out-of-furnace metal processing units, due to significant content in it of the unstable phase-dicalcium silicate, is prone to decay due to its polymorphous transformations, accompanied by an increase in the volume of the crystal lattice. Getting into cracks of the furnace lining, the slag can cause its destruction. The results of investigating the mechanism of stabilizing the refining slag by introducing alumina flux to it, while giving it the properties of mineral binders, are presented here. [ABSTRACT FROM AUTHOR]

Reducing the impact on the environment of constructing transportation infrastructures can be achieved through reusing or recycling certain materials. In this context, the current trend is to use materials that do not have a negative impact on the environment and provide a long term solution. Such local materials for the construction of transportation infrastructure are the active clays. This paper presents the physicochemical and mineralogical structure of clays and their behavior regarding the interaction with water. A negative effect of this interaction is the swelling, the contraction and, respectively, the swell pressure. These produce effects (fissures, cracks) in the structure of roads, highways and, respectively, airport runways. The authors analyze the possibility to reduce these effects by clay stabilization with mineral binders (cement, lime). Results on lime mixtures testing are presented in terms of physical and mechanical properties, and optimum percentages of the mixtures are presented. It is also concluded that this solution is more cost-effective than the classical one as replacing the clay layer from the roadbed with other filling materials transported from other areas.

The antimicrobial activity of different coatings for packaging materials consisting of a mineral binder based on liquid potassium silicate, non-conserved acrylates, and non-conserved styrene-acrylates as binders using functional, active extenders was investigated. The influence of time, temperature, and product factors on the antimicrobial activity against different bacteria were determined (ISO 22196:2007). showed a significant reduction in bacterial counts on all tested surface coatings compared to the reference, a glass plate without any coating, (24 h, 35 °C). Bacterial counts of Staphylococcus aureus , Escherichia coli , and Pseudomonas fluorescens were reduced between 3.32 (M8 against Staphylococcus aureus) and 7.01 log 10 units (M1 against Pseudomonas fluorescens). A high initial bacteria concentration (108 cfu ml−1) leads to a bacterial reduction between 1.21 (M8 against Staphylococcus aureus) and 7.57 log 10 units (M4 against Pseudomonas fluorescens). Incubation at a low temperature (7 °C) for prolonged storage (120 h) resulted in a reduced reduction rate for Staphylococcus aureus < 2.00 log 10 units. For most coatings, antimicrobial activity was shown in the presence of several food components as well as different pH values. The studied coatings show a high antimicrobial activity under different test conditions typical for perishable food supply chains and bear a high potential as a coating for packaging materials to increase the safety and quality of perishable products (in chilled storage). • Antimicrobial activity of organic coatings under conditions typical for chilled food. • High potential as coating for packaging to increase the safety and quality of food. • Mineral binder combined with biopolymer shows antimicrobial activity without additive. [ABSTRACT FROM AUTHOR]

Due to the increasing depth of coal mining, the particularly difficult and also specific conditions of the environment that are present in the Polish mining industry, the new technical problems appear. The efficiency of mining industry depends, among others, on limiting the influence of underground mining on rock mass and surface, maintaining the underground excavations, improving the ventilation conditions and properly implementing the fire prevention. In practice, for the implementation of these tasks appropriate technologies are being used, such as: constructing packwalls as well as insulating and explosion-proof dams, sealing of rocks, filling voids in rock mass and behind the support. The article presents the current state of theoretical and practical knowledge on protecting galleries of longwalls with cavings through the construction of a packwall made of mineral binders. The author describes pneumatic binder conveying system with individual components of this system. The paper presents successive calculation steps of the pneumatic conveying system used in coal mining. Mode of transport of mineral binders has a significant impact on their physical and mechanical properties. The choice of pneumatic transport to convey mineral mining binders confirmed itself in practice in coal mines: "Julian", "Piast", "Marcel", Szczygłowice", "Anna", "Rydułtowy". [ABSTRACT FROM AUTHOR]

With the aim of enhancing the industrial drying (hot air and microwaves) of inserts made of agglomerated sand and to assess product quality, a comprehensive internal heat and mass transfer model has been proposed. In this model, liquid and vapor transfer by filtration, liquid expulsion at the surface and binder transfer by advection were directly accounted for. This model was validated on the basis of the experimental average water and binder content and core temperature curves for drying trials at different operating conditions. Then, it was used for comparing the drying time, the internal pressure and the binder content calculated for several test processes. It was demonstrated that the simultaneous application of hot air and micro-waves provided a real possibility to dry faster and to maintain quite the same internal overpressure and overall binder content as for the reference (damage free) process. The heating power should be increased gradually during the process. The decrease of the drying time was around 30% with regard to the reference mild process. [ABSTRACT FROM AUTHOR]

The study aimed to determine the technological properties of cement-wood panels produced with the particle Eucalyptus benthamii Maiden et Cambage. The experiment plan consisted of four compositions with different treatments of the particles (cold water, hot water, sodium hidroxyde (NaOH) and calcium hidroxyde (Ca(OH)2 ), and a control composition. The panels were produced with nominal specific gravity of 1.20 g cm- ³, with the ratios wood:concrete 1:2.75 and water:cement 0.40. The panels were evaluated for their physical and mechanical properties through the European standard EN. Analyses were performed to verify the occurrence of outliers, data normality and homogeneity of variances, and subsequently submitted to analysis of variance and Tukey test. The results of physical and mechanical properties of the panels indicated that the best method of treating particles is through the use of Ca(OH)2 . With the exception of the modulus of rupture, the thickness swelling, modulus of elasticity and tensile perpendicular, they met the specifications of commercial panels produced by the BISON process. Therefore, the feasibility of use of Eucalyptus benthamii for wood-cement panels production was discovered. [ABSTRACT FROM AUTHOR]

Abstract: In the last few years novel binderless molecular sieves as high-performance materials were introduced into technical adsorption processes. Besides of the 100% active adsorption matter such material exhibits an advantageous secondary pore system. In this paper a more detailed investigation of the structure and the generation thereof is presented. To characterize the pore structure of the system SEM, EDX, Hg-porosimetry, as well as adsorption measurements (N2 and CO2) were used. For additional investigations XRD and XRF were applied. As a result of the special manufacturing process – granulation of zeolite NaMSX powder with metakaolin/caustic under high energy input followed by an alkaline treatment – two different types of zeolite morphologies were obtained: On the outer surface of the beads typical octahedral zeolite X crystals are monitored as a result of conventional and epitaxial crystal growth. In contrast the interior of the beads exhibits polycrystalline structures consisting of zeolite X in untypical shape, which is most probably the result of zeolite formation in dense matter. Due to the confined space conventional and epitaxial growth is inhibited. Obviously the original zeolite crystals are intergrown by polycrystalline zeolite NaMSX matter originated from converted metakaolin, and by the way forming macro pores. Said structure formation is the cause for the surprisingly high mechanical stability of the binderless shaped bodies. The existence of the superior secondary pore system and the high mechanical stability of binderless type NaMSX shapes can be explained as result of different pathways of the conversion of metakaolin into zeolite matter due to the existence of areas of different densities after the granulation process. [Copyright &y& Elsevier]