Raw Mixture Research Articles

Improving the Methods of Solid Domestic Waste Disposal to Reduce Its Human Impact on the Environment

Kazakhstan is embarking on a fresh approach to managing waste, aiming to recycle and repurpose solid household waste while integrating innovative, eco-friendly technologies for its treatment and disposal. The main goal is to reduce the amount of waste sent to landfills and instead convert it into more stable forms, lessening its harmful impact on the environment. This effort requires a comprehensive strategy, especially as existing landfills still need to be managed and rehabilitated when they reach capacity. It is essential to use municipal solid waste as a resource for producing various goods, which not only helps in landfill management but also aligns with principles of sustainability. This approach aligns with circular economic principles and helps to reduce the technological impact of landfills on the surrounding environment. The main types of waste in the Aktas landfill were identified as a result of this research: it is glass, of which only 3% is recycled. In our results, the setup allowed for the extraction of valuable components from the fine fraction, which can then be recycled. This enriches the organic material ready for composting (organo-mineral raw material mixture) with food waste.

Aspects of White Cement Production

The results of research aimed at the development of chemical technology for the production of white cement under the conditions of resource conservation and energy saving according to the program of sustainable development are given. Based on computer calculations using the created program “RomanCem”, the quantitative ratios of carbonate, aluminum and silica-containing components of the raw material mixtures for the production of white low-temperature firing cement (≤ 1200 °С) and Eco-cement were determined As a result of the study of 3-component systems based on chalk with aluminum hydroxide, dust quartz and microtalc, new compositions of starting mixtures were developed with a decrease in the content of carbonates and, accordingly, emissions of CO2 into the atmosphere, with a minimization of the content of colored oxides and a corresponding increase in the whiteness of cement. Peculiarities of the phase formation of the investigated mixtures during firing in the range of maximum temperatures of 1100-1200 °C and including the synthesis of ockermanite 2CaO•MgO•2SiO2 when using microtalc were revealed.

Improvement of construction and technological properties of cement hardening systems for building composites

The article provides information on the formation of hardening systems of building composites (STSC) as a result of directional structure formation and the involvement of the active component of metallurgical slags. It is shown that the structures of the STSC can be represented as a consequence of formation (design and synthesis) of the structures of the particle addition system of the raw material mixture, and for more complex technologies – as a growth system. The main physico-chemical properties and characteristics of modifying additives for STSC are considered. The influence of slag additives on the main construction and technological properties of hardening systems based on man-made raw materials has been established. Special attention is paid to the kinetics of the grinding capacity of the designed hardening systems of building composites.

Recycling of Rare Earth Elements: From E-Waste to Stereoselective Catalytic Reactions.

Raw mixtures of Rare Earths Elements, REE, recovered by E-waste, were used as catalysts to promote the (stereoselective) synthesis of highly valuable compounds. Y2O3, the major species that is recovered by the E-waste, can be easily converted into the catalytically active Y(OTf)3 that is able to efficiently promote the Michael addition of indoles to benzylidene malonates and the stereoselective Diels-Alder cycloaddition between cyclopentadiene and 4-(S)-3 acryloyl 4-tert-butyl 2-oxazolidinone. Additionally, the raw mixtures were immobilissed onto silica and used to construct packed reactors, resulting in values for Productivity and Space-Time Yields that were significantly higher than those of the corresponding batch conversions. Notably, the prepared cartridge employed in the model Michael reaction maintained its catalytic efficiency for more than 4 days of continuous running.

Petroleum cokes as pore generators in ceramic electrodes: Limitations for their use

The use of pore generators is a classical way to adjust the pore size distribution of porous ceramics. However, they must be selected to alter the processing of the ceramic as little as possible. Petroleum coke is an attractive pore generator for some ceramic compositions hard to process with other pore generators as starches. The analysis of the behaviour of the two main varieties, green coke and calcined coke, as pore generators in ceramic electrodes of Sb-doped SnO2 have shown that they allow the shaping of the electrodes by dry-pressing, but proportions higher than 10 wt% require great care in the process. The design of the sintering cycle is restricted by their thermal behaviour to a heating rate ≤ 2 °C·min−1 in the 150–600 °C interval to avoid defects in the sintered electrodes. Green coke undergoes a sudden expansion around 270 °C that is absent in calcined coke, but calcined coke oxidises at lower rate and its remainder can reduce SnO2 to Sn at higher temperatures. Calcined coke generates lower porosity in the sintered specimens than green coke at equal proportion in the raw materials mixture and requires higher proportions to obtain a bimodal pore size distribution. In addition, the type of coke has no definite effect on the properties of the sintered ceramic. In this work, the critical property, electrical resistivity of the electrodes, is mainly related to the generated porosity.The described limitations must be considered prior to select any of two cokes as pore generator in ceramics.

СТЕНОВЫЕ МАТЕРИАЛЫ ПОЛУСУХОГО ПРЕССОВАНИЯ НА ОСНОВЕ ГРАНУЛИРОВАННЫХ ИЗВЕСТНЯКОВЫХ ОТХОДОВ КАМНЕДОБЫЧИ

this article is devoted to the study of the processes of granulation of raw materials mixtures from limestone waste of stone mining and Portland cement and the production of wall materials based on them by semi-dry pressing. The optimal humidity-time parameters of the manufacture of granules were determined, laboratory samples of wall materials from granular mixtures with different contents of Portland cement were made. It was found that the compressive strength of samples from granulated raw materials exceeds the strength of samples from non-granulated raw materials by 3-12%. Subject of research: semi-dry pressed wall materials based on granular limestone waste from stone mining Materials and methods: Nummilite limestone waste from the Skalistoe deposit (Crimea) and Portland cement PC 500 DO from the Novorossiysk Cement Plant were used for the study. The physical and mechanical properties of the prototypes were determined by standard methods. Results: Experiments have shown that the compressive strength of samples made from granules containing 5-15% Portland cement and 85-95% of stone mining waste exceeds the strength of samples from non-granulated raw materials by 3-12%. Conclusions: The use of granular limestone waste from stone mining as the main component for the production of wall materials by semi-dry pressing makes it possible to increase their strength characteristics. The addition of Portland cement in certain proportions (5-15%) improves the strength characteristics of materials. Further research can be aimed at optimizing the composition of materials, studying their durability and adapting the production process to industrial scales.

Unravelling red deer (Cervus elaphus) meat adulteration in gourmet foods by quantitative real-time PCR

Red deer (Cervus elaphus) meat is highly regarded as an exclusive gourmet food due to its sensory quality, nutritional value and premium price, thus being susceptible to adulteration practices by its substitution with inferior meat species. This study proposes a novel real-time PCR method targeting the troponin I gene for detecting and quantifying red deer meat in processed food products. The assay showed acceptable performance parameters, achieving absolute and relative limits of quantification of 0.01 ng of DNA and 0.5% (w/w) of red deer meat in both raw and thermally processed pâté. The assay parameters, using raw and autoclaved reference mixtures, regarding PCR efficiency (89.3% and 100.0%, respectively), slope of the calibration curve (−3.6067 and −3.3224, respectively) and R2 (0.9889 and 0.9893, respectively) highlight the high performance of the calibration models for the determination of red deer meat. The method was successfully validated using blind mixtures and applied to 46 commercial meat products from Poland, Portugal and Spain. Data suggested the adulteration of 48% of the samples by the total or partial substitution of red deer species and the suitability of the method for the routine testing of game meat products in quality control laboratories.

Increasing softening point of isotropic spinnable asphalt by two-step preparation from ethylene tar residue modified with bio tar residue

Carbon fiber prepared from asphalt may be a critical type of low-weight chemical material of excellent mechanical performances. Here, an isotropic spinnable asphalt (EBA) was prepared from ethylene tar residue (ETR) by a two-step method of bio tar residue (BTR) through co-polymerization-air blowing, and isotropic asphalt carbon fibers were prepared from the product asphalt. The main types of molecules contained in the two feedstocks were determined by 1H NMR and LDI-TOF MS analyses. The co-polymerization behavior and thermal stability of the asphalt blends were analyzed using polarized light microscopy and thermogravimetric analyzer, respectively. Finally, the morphology and mechanical properties of carbon fibers made from EBA were evaluated by scanning electron microscope and universal testing machine. The results show that BTR contains much more oxygen-containing functional groups and unique long-chain sawtooth molecular structure; the former can promote the reactivity of the co-polymerization reaction, and the latter can limit the formation of large-plane cyclic aromatic hydrocarbon polymers due to the spatial resistance effect to greatly reduce the content of the mesophase. The softening point of the product asphalt shows a tendency of increasing and then decreasing with the increase of the proportion of BTR in the raw material mixture, and a reaction mechanism based on linear and bulky molecules is proposed to explain it by analogy with the structure of macromolecules. Consequently, the EBA made from a mixture of ETR and BTR at ideal moderate proportions has excellent performance in terms of softening point and mesophase content than ETRO made from ETR alone, and the carbon fiber made has a high tensile strength of 1.82 GPa with an elastic modulus of 38.9 GPa, which has reached the level of high tensile strength carbon fiber. Therefore, the use of inexpensive renewable energy bio-asphalt in the modification of heavy oil to obtain high softening point isotropic asphalt for preparing isotropic carbon fiber with excellent properties is achievable.

Analysis of Calorific Value of Biopellet Diameter Variations through Proximate Test

This study aims to evaluate the quality of biopellets as biomass energy fuel, focusing on physical and chemical characteristics based on the SNI 8021:2014 standard. The research method used is experimental with a non-factorial Completely Randomized Design (CRD). The raw materials used are a mixture of rambutan wood waste (Nephelium lappaceum L) and bintaro (Cerbera manghas) with tapioca flour as an organic binder. Testing includes proximate analysis (moisture, ash, volatile matter, and fixed carbon) and calorific value using an oxygen bomb calorimeter. The results show that the produced biopellets meet several parameters of the SNI 8021:2014 standard, such as moisture content, volatile matter, and fixed carbon. However, there is significant variation in ash test results among different diameters of biopellets tested. ANOVA test results indicate that mold diameter has a notation that has a significantly affect several biopellet characteristics, such as density and calorific value. This study also observed the potential for increased combustion efficiency of the produced biopellets. The results indicate that the raw material mixture used can reduce pollutant emissions during combustion. The conclusion of this study is that the use of a mixture of rambutan wood waste and bintaro with tapioca flour as an organic binder can produce biopellets with quality that meets standards for biomass energy applications.

Application of Hazard Analysis Critical Control Point (HACCP) principles to beef mortadella production

A mortadella is a cooked sausage made from raw pork, beef, chicken or lamb. It is popular in Jordan and neighboring countries for its taste, texture, nutritional value and ease of inclusion in sandwiches. The product is sold in plastic packaging, in circular rolls or vacuum packed. Although it poses no serious threat to human health, the heat can be dangerous if used improperly. A HACCP system is used to manage the production process, with a focus on quality control (CCP) throughout the manufacturing phase. Safety risks are identified at all stages of production, from raw materials to storage and distribution. Foodborne illnesses are primarily caused by pathogenic microorganisms, and these raw materials include pathogenic plant cells, Bacillus cereus, Clostridium botulinum and Clostridium perfringens that survive after cooking and contamination detected after monitoring. Post-manufacturing controls are performed through Good Manufacturing Practices (GMPs). The objectives of the study were to identify potential hazards associated with the production of beef mortadella, determine the CCPs to be implemented, develop a monitoring plan and establish corrective action on a case-by-case basis. The HACCP plan was developed in collaboration with local stakeholders and follows a process flow diagram to identify potential hazards and preventive measures. The system includes the steps for obtaining and storing the ingredients, preparing the meat, adding non-meat ingredients, and transferring the raw mixture to an incubator. The meat is weighed and filled with the mixture to improve cleanliness and avoid excess nitrite. The storage time between incubation and cooking is controlled to allow bacteria to multiply. To kill plant pathogens and reduce the total number of microorganisms, the product is cooked in a steam oven at 75°C for 5 minutes. The aim of the cooking process is to reduce microbial growth before lethal temperatures have been reached and uniform heating of the product has been ensured. Cooking suitability is checked by thermographic records and visual inspection of the cooked product. The plan also includes personnel in charge of every stage of production, ensuring a clean and hygienic environment. Key words: HACCP, Mortadella, meat processing, hygiene control, food safety

Reaction mechanism of Ca(OH)2-based carbon storage suitable for the production of building materials

The development of CaCO3 oxyfuel combustion and calcium looping techniques offers opportunities for Ca(OH)2 production with near-zero CO2 emissions. This study investigated the viability of Ca(OH)2-based CO2 storage for use in the production of building materials. To resolve the deficient strength gain of Ca(OH)2 carbonation, siliceous materials, using fly ash as a model compound, were introduced into the raw mixture, and hydrothermal curing was applied to promote the pozzolanic reaction. Two microstructural features, i.e., inner and outer CaCO3 formations, were identified during Ca(OH)2 carbonation via backscattered electron imaging. Inner CaCO3 formation is characterized by Ca(OH)2–CaCO3 conversion within the edge of Ca(OH)2 particles. Outer CaCO3 formation is characterized by the dissolution of Ca(OH)2 and the precipitation of CaCO3 in capillary pores, which generates hollow microstructures. The hollow space can be further filled by Al-tobermorite during hydrothermal curing. The prepared materials are capable of storing up to 16 % CO2 by the mass of the raw mixture. Furthermore, the pore structure influenced by inner and outer CaCO3 formation demonstrates the feasibility of adjusting the material's mechanical and CO2 storing properties by controlling the carbonation and hydrothermal curing schemes.

Fine-grained concrete properties in depending on carbon black additive introducing methods

The object of research is fine-grained concrete with carbon black additive obtained from the recycling of rubber tires. This study aims to determine a method for introducing carbon black into fine-grained concrete that achieves the best strength characteristics. The first method involves the preliminary preparation of a suspension by mixing a superplasticizer, carbon black, and part of the water. The second is the granulation of carbon black together with a superplasticizer in the ratio water: superplasticizer = 9: 1, followed by its introduction into the dry mixture and the addition of water at the last stage of mixing the raw material mixture. The addition of carbon black in powder form to the concrete mixture resulted in a decrease in strength from 35.1 MPa (without carbon black) to 34.9–25.6 MPa (with 4–12% carbon black). The effectiveness of the method of introducing granular carbon black was established, with an increase in strength by 40% in relation to the mixture obtained by the first method. The best strength of 50 MPa was demonstrated by the mix with 4% granular carbon black, which was 6% higher than that of the reference mix. Granulation of carbon black makes it possible to reduce its hydrophobicity and solve the problem of uniform distribution of carbon particles during homogenization of the raw material mixture in the presence of water.

(Keynote) Automated / Autonomous Platforms for Synthesis, Purification, and Characterization of Quantum Dots

Controlling composition, structure, and thus properties of nanomaterials continues to be of importance to numerous fields. For example, applications of quantum dots range from displays and bioimaging, to metal nanoparticles for (electro-) catalytic conversions. The vastness of synthesis parameter space, in combination with still limited understanding of the nucleation and growth mechanisms for many quantum dots systems still hampers progress in identifying nanomaterials with desired properties for existing and newly envisioned purposes. Furthermore, the identification of optimal synthesis recipes for these nanostructures remains a major hurdle.This presentation will report on the development and application a number of enabling capabilities for the synthesis and characterization of quantum dots, achieved through reactor engineering. We demonstrate how the use of automated flow reactors not only helps in run-to-run reproducibility but also in uncovering mechanistic information. Examples include reactors with dedicated nucleation, growth, and shell formation zones, and investigation that revealed mechanistic insight of how water concentration affects QD synthesis outcome. We also employed an autonomous flow reactor system to map synthesis parameter space of specific QD systems, a project that relied on fast, fully automated in-situ characterization using UV-vis or photo-luminescence in combination with multi-step machine learning workflows The utility of flow reactors, however, is limited when considering chemistries with longer reaction times. Hence, more recently we developed a fully automated batch reactor for parameter space mapping of QD synthesis via hot injection, the most frequently used method in both QD research and production at scale. This batch platform is being augmented with purification capabilities, to address some of the challenges of in-line, in-situ characterization of raw reaction mixtures, and to enable using advanced optical and structural characterization methods to provide insight into the actual structure of the QD materials.

Study of the influence of aromatic hydrocarbons on the process of tar oxidation

Abstract This study examines the impact of polycyclic aromatic hydrocarbons on the oxidation of petroleum tar. An aromatic hydrocarbon concentrates isolated from extracts of selective oil purification using the polar industrial solvent N-methylpyrrolidone was employed as an additive to tar. The relationship between the softening temperature of oxidized bitumen and both the duration of oxidation and the properties of the initial raw material mixture was investigated. It has been established that the introduction of 10 wt.% aromatic additive will increase the oxidation rate by 6 °C/h. The conditions for producing road bitumen from the proposed raw material compositions were identified. The influence of polycyclic aromatic hydrocarbon concentrate on the qualitative characteristics of bitumen during the tar oxidation process was determined. Aromatic additive is similar to a plasticizer, and reduces the softening temperature of bitumen by 9 °C. But the combined oxidation of tar with an aromatic additive and a catalyst makes it possible to obtain bitumen with a softening point of 44 °C and a penetration of 80 x0.1 mm, which corresponds to the grade of bitumen 70/100. Analysis of the group composition of oxidized bitumen revealed that the aromatic additive facilitates the intensification of the tar oxidation process.

Effects of Si4+/Al3+ molar concentration ratio on the self-reduction process of Yb3+ to Yb2+ ions and optical properties of Bin+/Ybm+, Bin+/Er3+ and Bin+/Er3+/Ybm+ (n, m = 3, 2) co-doped magnesium aluminum silicate glass

In this paper, we investigate and report the effects of Si4+/Al3+ (SiO2/Al2O3) molar concentration ratio on the self-reduction process of Yb3+ to Yb2+ ions and upconversion (UC)-, visible (VIS)- emission spectra, direct optical bandgaps (DOB), indirect optical bandgaps (IOB) of Bin+/Ybm+, Er3+/Bin+, and Er3+/Bin+/Ybm+ (n, m = 3, 2) co-doped SiO2–Al2O3–MgO–TiO2 (SAMT) magnesium aluminum silicate glasses. The valence states of the bismuth (Bi), and Ytterbium (Yb) elements in the raw materials mixture existing in the SAMT glass were determined using X-ray photoelectron spectroscopy (XPS) spectra analysis. With the increase of Al3+ molar concentration from 16 mol. % up to 20, 24, 28 and 32 mol. % corresponding to the Si4+/Al3+ (SiO2/Al2O3) molar concentration ratio of 3.4, 2.5, 1.9, 1.5, and 1.2, the self-reduction process of Yb3+ to Yb2+ ions was enhanced and thus significantly affected the DOB, IOB, the intensities of UC-, VIS- emission spectra of Bin+/Ybm+, Bin+/Er3+, and Bin+/Er3+/Ybm+ (n = 2, 3) co-doped SAMT glasses under excitation of 473 nm, 808 laser diode (LD) and 980 nm LD. In addition, the CIE 1931(x, y) color coordinates for VIS- and UC- emissions spectra of Bin+/Ybm+, Bin+/Er3+ (n = 2, 3) co-doped SAMT under excitation of 473 nm and 808 nm LD are also calculated and determined in the CIE 1931(x, y) chromaticity diagram.

Mining Enterprise Production Line Optimal Load Modelling

The article is devoted to the issues of the mining enterprise production line optimal load model. A large number of issues to related to alternative production plan implementation transition are considered in various works. A mathematical model to form an optimal plan mining enterprise raw material mixture from deposits is proposed in the study. A method of multi-criteria alternative ranking in terms of integral efficiency indicator with the following problem solution of optimal plan determination for a raw material mixture from deposits was chosen for that purpose. The article proposes an approach to determine the production line optimal loading plan of a mining enterprise based on the creation of an ore mixture with the highest utility. The value of a particular deposit is determined by a variety of factors, including the distance from the production line, the ore content in the rock, and the volume of the deposit. The paper shows that the development of a specified field management can be implemented based on solving linear programming problems. The hierarchy contains three levels: the system purpose; the factors influencing the deposit appeal (the metal content, the deposit volume, and transport accessibility); alternatives (deposits of raw materials directly). Let's assume that it is necessary to find the maximum efficiency by means of an ore mixture from the given deposits. Resource restrictions are imposed on the task: the work and machine time fund, the amount of first type reagent, and the amount of second type reagent. The composition of the constraint vector can be set depending on the value of the resources. The study found that the optimal plan is implemented under the complete resource utilization both of the first and the second types and a fifty-three percent level of the third resource utilization. Despite the low integral assessment of the raw material value of the fourth deposit, which is mainly determined by the low ore content in the rock, with respect to other deposits, its maximum utilization is also recommended, which in turn, is determined by the low resource intensity of ore extraction from this rock.

Production of Composite Cement Clinker Based on Industrial Waste

The possibility of producing cement clinker using low-energy, resource-saving technologies is studied. The composition of industrial waste for low-energy-intensive production of Portland cement clinker at factories in Southern Kazakhstan is analyzed. The possibility of replacing the deficient iron-containing corrective additive with “Waelz clinker for zinc ores” is shown. “Waeltz clinker from zinc ores” as part of the raw material charge performs several tasks: it is a ferrous corrective additive, works as a mineralizer for clinker formation processes, introduces coal into the charge and allows one to reduce the consumption of natural fuel. The processes of burning raw mixtures, wholly or partially consisting of industrial waste, are completed at 1350 °C. This reduces the consumption of main burner fuel for clinker burning and reduces CO2 emissions into the atmosphere. High-quality cement clinker is obtained based on raw material mixtures with Waeltz clinker from zinc ores from the Achisai Metallurgical Plant, phosphorus slag, coal mining waste from Lenger mines and sodium fluoride. The phase composition and microstructure of low-energy clinkers are revealed. Involving industrial waste in raw material circulation will reduce environmental pollution and improve the environment.

Enspectrumix: Novel adaptive methodology for fault component extraction from vibration mixtures

Machine condition monitoring is important in industry to monitor machine health conditions and avoid unexpected machine breakdowns. Vibration mixtures contain sufficient machine health information, but they have lots of vibration interferences. Therefore, it is crucial to adaptively extract fault components from vibration mixtures. Blind-filter-based methods have been extensively studied to extract fault components and they use impulsiveness and cyclo-stationarity properties as prior knowledge to optimize signal processing parameters. The difficulties of state-of-the-art methods include that: (1) statistical indices (e.g., kurtosis, Gini index, correlated kurtosis, etc.) cannot simultaneously characterize impulsiveness and cyclo-stationarity properties so that blind-filter-based methods are always affected by impulsive noise and low-frequency components, resulting in unreliable performance for fault components extraction; (2) optimization of signal processing parameters is time-consuming; (3) band-in noise cannot be removed; (4) only a frequency band rather than several frequency bands can be adaptively selected, resulting in the incomplete fault components extraction. Instead of using the aforementioned prior knowledge, this paper reports a new perspective that use healthy vibration mixtures as prior knowledge to improve the existing blind-filter-based methods and provide more reliable fault components extraction for practical implementation in industry. Firstly, an ensemble difference spectrum-based new index is proposed to provide a completely new perspective for traditionally existing statistical indices. Subsequently, it is theoretically proved that the new index satisfies two new properties for quickly and better quantifying fault components. Next, a new methodology named Enspectrumix is designed to decompose a raw vibration mixture into sub-signals and use the newly designed index to adaptively select informative sub-signals existing in different frequency bands. The effectiveness and superiorities of the proposed Enspectrumix are validated by two real-world dataset cases. Moreover, the Enspectrumix can be extended to extract concerned difference components in many other domains.

Energy-saving technology of silicate pressed material with use of micro-porous silica-earth raw materials

Purpose. Research on the possibility of producing a silicate material that hardens under reduced parameters of autoclave processing, due to the introduction of natural zeolite into the raw material mixture. The methods. To solve the problems set in the work, following methods were used:generalization and analysis of theoretical and experimental data of domestic and foreign authors; analytical studies of raw materials (chemical, mechanical and physical-mechanical methods); laboratory experiment using physical and mechanical tests. The study of the properties of raw materials was carried out according to standardized methods. Findings. It has been proven that natural zeolite is an effective component of silicate pressed materials for reducing heat energy consumption during their autoclaving. It was established that with a low zeolite content, the compressive strength of lime-zeolite stone practically does not differ from the strength of limestone-sandstone. A study of the influence of the autoclave treatment regime on the strength of silicate pressed concrete, which was made using a lime-zeolite binder, was carried out. It has been experimentally confirmed that the strength-to-strength ratio of pressed silicate material on a lime-zeolite binder (compared to a similar pressed silicate material on a lime-sand binder) depends to a lesser extent on the water vapor pressure during autoclaving. The originality. The dependences of the compressive strength limit of samples-beams made of lime-zeolite binder at different mass ratios of lime:siliceous component, as well as the dependence of the compressive strength limit of silicate pressed materials on a lime-zeolite binder on water vapor pressure during autoclave processing. Practical implementation. The results of the research can be used at enterprises of the building materials industry in the production of silicate bricks. Replacing natural quartz sand with natural zeolite reduces the production cost of lime-zeolite binder, and the reduction of water vapor pressure during autoclaving of silicate pressed material on lime-zeolite binder reduces the consumption of high-value natural gas.

СИНТЕЗ И СВОЙСТВА КАЛЬЦИЕВО-АЛЮМОФЕРРИТОВОГО ЦЕМЕНТА С ИСПОЛЬЗОВАНИЕМ ТЕХНОГЕННЫХ МАТЕРИАЛОВ

The article discusses the production of calcium-aluminoferrite clinker (cement) from a three-component mixture (by sin-tering), where 56.2-57.4 wt.% of the mixture consists of aluminum– and iron-containing man-made waste. It was found that the use of man-made waste as a component of the raw material mixture leads to a decrease in the amount of waste generat-ed by 4.9-5.4%, based on the production of 300,000 tons of calcium-alumoferrite cement per year. The results of qualitative and quantitative X–ray phase analysis of the clinkers obtained are presented, which indicate the formation of calcium aluminates (CA,C3A,C12A7), calcium aluminoferrite(Ca2(Al,Fe)2O5) and calcium silicate (α-, β-C2S) as the main clinker phases in all samples. Clinker phases of aluminate and calcium aluminoferrite are formed not in pure form, but with the introduction of impurity elements (Mg2+, Ti4+). Determination of the hydration activity of CAFC showed that the quantitative ratio of clinker phases CA:Ca2(Al,Fe)2O5 = 38.8:33.8 (CAFC I) and CA:Ca2(Al,Fe)2O5 = 27.6:23.9 (CAFC II) leads to an increase in the strength of cement stone in the initial periods of hardening by 48 and 32 MPa, and in later periods (28 days) - to an increase in strength by 28 and 8 MPa, respectively.