Elena. A. Belyanovskaya

Promising directions of synthesis from renewable vegetable oil raw materials of monomeric and oligomeric oleochemical products are considered: modified triglycerides as ingredients of special-purpose polymer compositions; fatty alcohols, esters and amides of fatty acids as surfactants in detergents, cosmetics, paints, pharmaceuticals, as ecological fuel; polyols and hydroxyl-containing oligomers for the synthesis of polyurethane, polyesteramide, polyurethaneamide binders and coatings with anti-corrosion and antimicrobial properties. The synthesis routes of fatty acid amides, in particular hydroxyl-containing ones with a functionality of 2 or more, as starting compounds for promising polyesteramides are considered in detail. The strategy of synthesis from vegetable oils of saturated polyols with primary hydroxyl groups as promising components for environmentally friendly paint and varnish compositions is considered. Data on the synthesis and properties of polyurethaneamides, polyesteramides and metal-containing derivatives based on them are presented. For each product type an analysis was made of the state of development of a particular technology, as well as future prospects and existing barriers to their development. The possibility of using metal-containing polymers to create biodegradable materials and coatings with hydrophobic properties and antimicrobial activity was shown.

Performance of an adsorptive heat pump has been studied. The factors affecting the efficiency of its work have been analyzed. Operating parameters and efficiency of adsorptive heat pumps and adsorptive heat storage devices have been compared. An algorithm of calculating the basic operating characteristics of an adsorption heat pump in heat supply systems has been proposed. It involves calculating the mass transfer coefficient, final absolute humidity of the air flow passed though adsorbent layer, the water uptake or adsorption and the useful heat of adsorption and heat of condensation, determination of heat inputs for the operation of the device such as heating the adsorbent, case of the device, hydraulic circuit, the water in the tank and adsorbed water, heat of desorption and heat of evaporation, estimation the coefficient of energy performance. The evaluation criteria of the efficiency of adsorptive heat pumps and heat storage devices have been compared. It is shown that the operating parameters of the adsorptive heat pump and the adsorptive thermal energy storage device based on composite adsorbents ‘silica gel – sodium sulfate’ and ‘silica gel – sodium acetate’ are the same, i.e. airflow rate 0.08 - 0.1 m3/s and initial absolute humidity of airflow 0.03 – 0.04 kg/m3, which are corresponded with maximal efficiency of the device. The temperature of the humid air flow directed to the adsorbent layer is suggested to be set at 20 – 40 °C. The measures to increase the efficiency of the adsorptive heat pump are proposed. It is shown that ultrasonic air humidification allows to increase the coefficient of energy performance by almost 2 times compared to steam humidification. The obtained results can be used for developing energy-efficient heating systems of residential premises.

Global trends suggest that 21st-century science and technology will be nanoscale, as traditional technologies have exhausted the potential for miniaturizing individual elements, prompting the search for alternative pathways. Nanophase materials science differs from the traditional one not only by the creation of fundamentally new materials, but also by processes that take place at the atomic and molecular levels, monolayers, and nano volumes. Polymer-Inorganic Nanostructured Composites Based on Amorphous Silica, Layered Silicates, and Polyionenes is devoted to the development of physical and chemical principles of technology for polymer-inorganic nanostructured composites based on amorphous silica, layered silicates, and polyionenes to use the creation of composites for technical purposes. Covering topics such as fractal structure, phosphoric-organic compounds, and proton conductance, this premier reference source is an essential resource for chemists, engineers, students, and educators of higher education, researchers, and academicians.

Exergy analysis of an open-mode adsorptive heat storage unit has been performed when a composite ‘silica gel – crystalline hydrate’ used as an adsorbent. The crucial factors affecting the exergy efficiency factor are stated to be temperature and initial humidity of airflow supplied to the inlet of adsorbent layer, temperature of external air and methods of air flow humidification. Procedure of calculation of the operating characteristics of an open-mode adsorptive heat storage device was further developed. The suggested procedure involves determination of adsorption, specific adsorption heat and final airflow temperature, useful heat, heat inputs for operating heat storage device and its efficiency factor, then exergy recovered, exergy supplied and exergy efficiency are calculated. Exergy efficiency depends on characteristics of flow of humid air fanned into the adsorbent layer such as temperature and initial absolute humidity which strongly affect the adsorption and final airflow temperatures. Increase of initial temperature of the humid air leads to decreasing of the exergy efficiency. Maximal values of exergy efficiency are determined at the absolute humidity and temperatures of initial airflow within the ranges of 0.03 – 0.04 kg/m3 and 20 – 30ºC, respectively. These characteristics are corresponded to the maximal airflow temperatures after passing through the adsorbent layer which meet to the Sanitary Regulations. Dependence of exergy efficiency vs. external air temperature and initial airflow temperature is shown. The exergy efficiencies of the open-mode adsorptive heat storage unit with steam and ultrasonic humidification were compared. Ultrasonic humidification is shown to allow increasing the exergy efficiency by 7 % against steam humidification. The obtained results can be used when energy-efficient heat and ventilation systems for residential premises developed.

A systemic study of the possibility of regulating the deformation-strength, adhesion and dynamic mechanical properties of epoxy-polysulphide composites based on the products of the preliminary thioetherification reaction (PRTE) by varying the concentration of polysulphide rubber, as well as changing the amount of the hardener and using a mineral filler has been carried out. An increase in the content of rubber in the product of the preliminary thioetherification reaction was found to promote an increase in the characteristics of cohesive and adhesive strength, deformation at break and the work of destruction of the material. An increase in the complex of properties is assumed to result from the formation of higher molecular weight products with an increase in the rubber content in the composition subjected to PRTE. The formation of such products is confirmed by the data of dynamic mechanical spectrometry. It has been shown that by changing the amount of the introduced hardener, i.e., by changing the ratio of amine and epoxy groups, it is possible to effectively regulate the deformation and strength characteristics of epoxy-polysulphide mixtures. With an increase in the content of the hardener, the tensile strength, deformation at break and the work of destruction of the material increase very significantly. It was found that the introduction of a filler into an epoxy system containing a large amount of rubber promotes an increase in cohesive strength with a relatively small decrease in adhesion strength and deformation at break.

Thermal conditions of adsorptive heat storage device operating in open-mode were considered when discharged. The main operating parameters affecting the final temperature of airflow which supplied to ventilated premises are determined on the example of heat storage device based on composite ‘silica gel – sodium sulphate’. The main factors which determine a final airflow temperature are confirmed to be initial values of temperature, absolute humidity and speed of airflow which fanned to the adsorbent layer. Algorithm of calculating the operational parameters of adsorptive heat storage device has been further developed. Proposed algorithm involves calculation of diffusion coefficient, mass transfer coefficient, final absolute humidity of airflow, volume of air which passed through adsorbent layer, adsorption, specific adsorption heat and final airflow temperature, then useful heat, heat inputs for operating heat storage device and its efficiency factor are estimated. The adequacy of the proposed algorithm has been confirmed according with experimental data for operating of open mode adsorptive heat storage device. Curves final temperature of inflowing air vs. time of discharge of heat storage device are stated to depend on characteristics of airflow which fanned to the adsorbent layer such as temperature, speed and initial absolute humidity. When these parameters increased, time to achieve plateau, i.e. maximal values of final inflowing air temperature decrease. The dependence of initial values of temperature, absolute humidity, speed of humid airflow and final airflow temperature is shown. Maximal temperatures of at most 65 – 80 ºC are stated at the initial temperatures and absolute humidity of initial airflow within the ranges of 20 – 30 ºC and 0.03 – 0.04 kg/m3, respectively. The results of the present study can be used for the development of energy-efficient systems and devices for air-conditioning in habitual inner space and warehouses.

The performance of the adsorptive heat-moisture regenerators based on the composite materials ‘silica gel - sodium acetate’ and ‘silica gel – sodium sulphate’ have been studied. The mathematical model and algorithm for determining the basic operating parameters of adsorptive regenerator in the housing and communal services sector have been further developed. The proposed algorithm which involves calculating the air volume passed through the adsorbent layer, the final absolute humidity of air near the outlet from the regenerator, the adsorption and the heat of adsorption during inflow and outflow, the final temperature of the external cold air, the air temperature after mixing the cold external air and the internal warm air in the room near the warm end of the regenerator during inflow, the air temperature after mixing of the cold external air and the warm exhaust air from the premise near the cold end of regenerator during outflow, determining the temperature and moisture efficiency factors has been completed by computing the Reynolds criterion of the adsorbent layer, the coefficient of the hydraulic resistance, the pressure loss, the consumed power of ventilator, summarized adsorption and time to achieve maximal adsorption . The adequacy of suggested mathematical model is confirmed by sufficient correlation of experimental data and calculation results with the proposed algorithm. The performance of adsorptive regenerators based on the adsorbents ‘silica gel – CH3COONa’ and ‘silica gel – Na2SO4’ has been simulated in the conditions of the conventional ventilation system of living quarters. The efficiency of adsorptive regenerators has been compared when ‘silica gel – CH3COONa’ and ‘silica gel – Na2SO4’ used. The correlation of design and efficiency of adsorptive regenerators is shown.

The work is focused on the development of an effective algorithm for calculating the operational characteristics of a steamcompressive chilling machine with an adsorptive chilling unit, which involves a cold box, an adsorber, an evaporator and a condenser, water being used as a refrigerant. An algorithm for calculating the operating parameters of the adsorptive chilling unit has been developed, which includes the determination of the cooling capacity of the steam compressor refrigeration unit, the heat load on the condenser, the power consumed by the compressor, the coefficient of performance of the steam compressor refrigeration unit, as well as the calculation of the mass of water, the mass of the adsorbent, the refrigerating capacity, the coefficient of performance of the adsorptive chilling unit and the coefficient of useful energy utilization of a steam compressive chilling machine with an adsorption chilling unit. The chilling capacity and the coefficient of performance of the adsorption chilling unit are estimated under the operating conditions of a typical steam compression chilling machine. The crucial factors affecting the efficiency of the adsorptive chilling unit are analyzed. It has been established that the chilling capacity, the coefficient of performance of the adsorption refrigeration module and the energy efficiency of the installation are determined by the thermal load on the condenser, and, therefore, by the mass of water that is desorbed and evaporated. The coefficient of performance of the adsorption chilling unit and the efficiency of the steam compressor chilling machine with the adsorptive chilling unit are estimated to be 0.878 and 4.64. The criteria for the selection of adsorbents for the adsorption module are analyzed. The temperature of regeneration is determined by the temperatures in the condenser, and the limit adsorption affects the mass of the adsorbent and the size of the adsorber. A comparison of the efficiency of adsorptive chi l l ing uni t based on silicoaluminophosphates and composite adsorbents «silica gel – sodium acetate» is carried out. The prospects of using composites «silica gel – СН3СООNa» are shown. The optimal composition of the composite was established, which corresponds to the minimal size of the adsorber, (80% sodium acetate and 20% silica gel). The prospects of using adsorptive conversion of thermal energy for utilization of low-potential thermal energy during the operation of steam compressive chilling machine are shown. Keywords: adsorptive conversion of heat energy, composite adsorbent, steam compressive chilling unit, adsorption, adsorptive capacity.

The performance of an adsorptive heat-moisture regenerator based on a silica gel–sodium sulphate composite adsorbent was studied. The correlation between the adsorbent composition and structural characteristics of the laboratory-scale device was investigated. An algorithm for the calculation of the efficiency factors of the adsorptive regenerator was further developed. The suggested algorithm calculates the operational parameters, including the temperatures, humidities and volumetric flows of internal and external air, and estimates the regenerator’s performance via temperature and moisture efficiency factors, total adsorption and time needed to achieve maximum adsorption, air pressure loss and fan power input. The validity of the calculation results obtained using the proposed algorithm was confirmed experimentally. Temperature efficiency factor, air pressure loss and fan power consumption are crucial parameters for the estimation of the optimal operating regime of an adsorptive heat-moisture regenerator. The correlation between meteorological conditions and efficiency factors was assessed and applied in a simulation of residential house-scale air conditioning unit operation. Maximal values of temperature efficiency factor were found at internal and external air temperatures of 15 to 20 °C and −5 to 0 °C, respectively. Moisture efficiency factors were observed to reach their maximum at the absolute humidities of external and internal air of 4.0 to 5.0 g/m³ and 2.75 to 3.0 g/m³, respectively. The fan power consumption of the adsorptive heat-moisture regenerator was found to be comparable to or even lower than that of commercial air conditioning units used in comparably voluminous interiors.

Heating flame furnaces are the main type of furnaces used for heating and heat treatment of metal products in metallurgy and mechanical engineering. In the working chamber of a modern heating furnace, there should be neither high-temperature nor stagnation zones. One of the methods used to provide such combustion conditions is the application of distributed (volumetric) combustion. Owing to this method, heating quality is ensured by creating a uniform temperature field and equivalent heat exchange conditions, regardless of the placement of the charge in the working chamber of the furnace. In this work, we numerically study the volumetric combustion and influences of small- and large-scale recirculation ratios of furnace gases, the influence of temperature fluctuation on the regenerator nozzle, and the working parameters at the starting phase and reverse.