Carbon Dioxide Consumption Research Articles

INTENSIFICATION OF SUPERCRITICAL EXTRACTION OF TRITERPENE SAPONINS FROM ARALIA MANDSHURICA AND PANAX GINSENG

This work is devoted to experimental research of the extraction of triterpene saponins from Aralia mandshurica and Panax ginseng using the supercritical extraction process. Triterpene saponins of Aralia mandshurica and Panax ginseng are polar compounds. Therefore, the supercritical extraction process was carried out in a supercritical carbon dioxide using a co-solvent – an aqueous solution of ethanol. A technique for carrying out the supercritical extraction process is described and a schematic diagram of a supercritical extraction apparatus proprietary design with an extractor volume of 22 ml is presented. The kinetic curves of the yield of extract are presented. This work is considering methods of intensification of the supercritical extraction process: optimization of operational conditions, superposition of fields. Optimization of operational conditions was carried out in the temperature range of 40 to 50 °С and pressures range of 120 to 200 bar. The phenomenon of retrogradation was noted when the temperature of the supercritical extraction process from Panax ginseng changed. The influence of the method of supplying supercritical carbon dioxide (constant supply throughout the process and pulse supply) was studied. The pulsed supply made it possible to significantly reduce the consumption of carbon dioxide – by 59.5% relative to the experiment with a constant consumption of carbon dioxide. The study of the effect of ultrasonic exposure (the method of superimposing fields) on the intensity of the supercritical extraction process was carried out. The usage of ultrasound led to an increase in the yield of extract. The largest amount of extract from Aralia mandshurica and Panax ginseng was obtained at 50 °С and 200 bar with the usage of ultrasonic exposure and at a constant supply of carbon dioxide (500 g/h) throughout the process. For citation: Khudeev I.I., Lebedeva E.S., Artemiev A.I., Kazeev I.V., Menshutina N.V. Intensification of supercritical extraction of triterpene saponins from Aralia mandshurica and Panax ginseng. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2023. V. 66. N 3. P. 108-118. DOI: 10.6060/ivkkt.20236603.6737.

Evaluation of carbon dioxide emission reduction in an energy cycle based on biomass gasification and molten carbonate fuel cell: exergoeconomic and environmental analyses

Abstract A competitive advantage for the molten carbonate fuel cell (MCFC)-driven energy processes is their fuel versatility. On the other hand, since MCFC consumes carbon dioxide, it can reduce the amount of carbon dioxide emissions compared with other fuel cells. Accordingly, the current paper develops and evaluates the thermodynamic, exergoeconomic and environmental analyses of a new hybrid energy process (HEP) based on a reformer MCFC stack and a biomass gasification process. A homogeneous ignition engine (HIE) and a heat recovery system are two other main units embedded in the developed HEP. In the developed cycle, MCFC and HIE produce electric energy, for which the required fuel is supplied through the obtained syngas from the biomass gasification process and the anode off-gas, respectively. The heat recovery system also leads to the establishment of the thermal balance of the energy cycle by recovering the thermal energies of the MCFC and HIE. The aim of the present work is to develop the multi-aspect evaluation of the proposed energy system toward a fruitful implementation feasibility analysis. The outcomes indicated that the rates of electrical and thermal powers obtained from the planned HEP were equal to nearly 1112 and 367 kW, respectively. Further, the calculated efficiencies for electric, gross power and total energy terms were equal to 51.5%, 55.7% and 69.9%, respectively. The developed HEP had 48% less carbon dioxide emissions compared with a petroleum-fired power plant, 15.8% less compared with a natural gas-fired plant and approximately 63% lower compared with a coal-fired power plant.

Impact of Digital Marketing Practices on Energy Consumption, Climate Change, and Sustainability

The term “sustainability” is now omnipresent in all sectors of the economy, particularly today in the business sector. Consumers are pressuring businesses to improve their day‐to‐day operating processes by becoming more environmentally friendly and minimizing their negative impacts on society and the environment. Prior to the COVID‐19 pandemic, online shoppers worldwide began rejecting goods and services from companies that violate social norms as well as personal values. The longer‐term remote work status of a large percentage of the global population following the pandemic has served to fuel the sustainability movement throughout the world, as consumers have transitioned from offline to online businesses. As a result, online businesses have begun promoting their products vigorously through digital marketing and advertising. This transition is realizing significant environmental and sustainability benefits through the reduction of energy consumption and levels of carbon dioxide (CO2) emissions generated. Against this backdrop, this article attempts to explain the impact of digital marketing on climate change and sustainability, including the estimation of possible environmental damages resulting from digital marketing, why digital marketing companies need to have a sustainable business strategy, and future efforts needed to ensure a sustainable environment.

Efficacy of Medicinal Woods/trees Vis-a-Vis Environmental Pollution

Woods/trees a lovely, non-demanding, and most kind entity on our earth. All living beings on this planet depend on the wood/trees in some prospective. As they fight against not only against the diseases but tackles environmental pollution which is brought on by increased industrialization, excessive use of chemicals and plastics. Wood/trees play a crucial role in maintaining a healthy atmosphere and stabilize our climate. By limiting the passage of dangerous pollutants and dust particles, wood/trees also enhance the quality of the air. Few medicinal wood/trees, by virtue of their brilliant purifying abilities and therapeutic advantages, beyond treating diseases plays a significant role in the management of environmental pollution. Woods/trees by consuming carbon dioxide by the process of photosynthesis in potentially diminish environmental pollution by locking up the carbon which is caused by the burning of fossil fuels. Ancient System of Medicine, Ayurveda also has suggested to plant trees like Emblica officinalis Gaertn., Cedrus deodara Roxb. etc. and herbs like Ocimum sanctum Linn. to encounter environmental pollution. The present study will discuss strategic methodology of selected woods/trees in context to traditional synonyms mentioned and their mode of action to tackle environmental pollution.

​An Engineering Approach to Estimating Carbon Dioxide Consumption and Recovery Potential in the Brewery​

​An Engineering Approach to Estimating Carbon Dioxide Consumption and Recovery Potential in the Brewery​

Exhaust emissions reduction and fuel consumption from the LNG energy system depending on the ship operating modes

In today’s environment of increasing pressure to reduce fuel consumption and emissions of carbon dioxide (CO2) and nitrogen oxides (NOx), the LNG (Liquefied Natural Gas) transportation industry is growing in size and influence. In this context, further efforts are needed to improve the energy efficiency of LNG marine energy power plant. The LNG vessels and their equipment considered in this study have different power consumption requirements depending on the vessel’s mode of operation (loading/unloading, maneuvering, anchoring, at sea, etc.). For each ship mode, where the power plant requirements are the same, the specific fuel consumption (SFOC) and exhaust emissions, NOx and CO2, are compared with a different number of engines in the network to find the optimal number of engines in the network, considering both the safety aspect and the port requirements. An analysis was performed showing the efficiency of the on-board power management system (PMS) in terms of manual load sharing between engines. A comprehensive analysis of the data and its comparison led to the conclusion that the manual distribution of power among the engines is the slightly better solution. The obtained results show that further analysis of the number of engines for a given load with minimum fuel consumption and CO2 and NOx emissions is required.

Life cycle assessment of MycoWorks’ Reishi™: the first low-carbon and biodegradable alternative leather

BackgroundOver the past few years, several alternative leather technologies have emerged and promise advantages over incumbent leathers with respect to sustainability despite most containing enough plastic to prevent safe and effective biodegradation. Of the alternative leathers in production or advanced development, few fit the dual criteria of low-carbon and near-zero plastic. Reishi™ is a leather alternative, grown using MycoWorks’ Fine Mycelium™ technology, with less than 1% polymer content and satisfies the same performance, quality, and hand feel as animal leather. We present here the first Life Cycle Assessment (LCA) of Reishi™, detailing its “cradle-to-gate” carbon footprint and broader environmental profile. The pilot- and full-scale production of 1 m2 of post-processed, finished, and packaged Reishi™ both before and after production improvement implementations is modeled, and the environmental footprint impact assessment method is performed.ResultsIt was found that Reishi’s™ carbon footprint is as low as 2.76 kg CO2-eq per m2, or 8% of the value of the bovine leather benchmark modeled. Furthermore, it was found that Reishi™ has a lower impact compared to bovine leather modeled across a number of impact categories, including eutrophication, ecotoxicity, human health effects, and others. Reishi’s™ impact “hotspots” were determined, with the largest opportunity for further reduction being improved energy efficiency in the growth of mycelium, in particular, the process’s sterilization of raw material inputs via autoclave tools. It is also shown that MycoWorks’ passive process for growing mycelium has a carbon footprint two orders of magnitude lower than incumbent mycelium growth processes that actively consume carbon dioxide gas, which MycoWorks’ process does not require.ConclusionsReishi™ is shown to be a promising sustainable material through its unique combination of natural quality, low-carbon footprint as determined by this LCA, and biodegradability due to its lack of plastic or crosslinked content. Its manufacturing process is low impact even when produced at a scale of tens of thousands of square meters per year—a miniscule fraction of the billions of square meters of bovine leather already sold per year. With further use of this leather alternative, additional efficiency gains are likely to be realized.

Elementary evolution in coal under natural conditions: Coals affected by igneous intrusions

The elementary evolution of coals affected by igneous intrusions differs from the track of coals that have undergone normal coalification. This evolution pathway is related to the natural geological conditions. To study the evolution of coals affected by igneous intrusions, a sizeable amount of data from our group and from previous works were collected and comprehensively analyzed. Based on the analyses, the H/C vs O/C evolutionary diagrams of coals affected by igneous intrusions was plotted, and three evolution pathways (Tracks I, II, and III) were found. Track I is a curve similar to the evolutionary track of coals that experienced normal coalification, as would be seen in the van Krevelen diagram. Track II is a straight line starting from H/C of about 0.8. Compared with Tracks I and II, the O/C atomic ratio is anomalously high in Track III. Track I is formed by a combination of comparatively slow dehydrogenation and fast deoxygenation; Track II is formed by a combination of comparatively faster dehydrogenation and slower deoxygenation; and Track III is formed by a process resulting in increased oxygen content, and regardless of dehydrogenation. Carbonate minerals played an important role in the anomalously high O/C atomic ratio in Track III. However, carbonate minerals were affected by temperature, and a high temperature can form pyrolytic carbon in coals affected by intrusions and reduce carbonate minerals content by consuming carbon dioxide. Coals with anomalously high O/C values are not coals that were in direct contact with intrusions but are found at a certain distance from the intrusions.

Modern Technologies for Converting Microalgae Biomass into Various Kinds of Biofuel

Searching for alternative sources of biomass as a raw material for bioenergy is currently an urgent fundamental and applied scientific problem. Microalgae, due to the peculiarities of their physiology, high productivity, and the potential to consume carbon dioxide from the atmosphere, are one of the examples of such sources. The article presents the results of long-term research conducted at the Moscow State University’s Laboratory of Renewable Energy Sources on developing a technology for large-scale cultivation of microalgae, methods for increasing their productivity in terms of biomass and target products (lipids and carbohydrates), and obtaining various types of biofuels from biomass (biodiesel, bio-oil, synthesis gas, methane, etc.). The possibility of associated wastewater treatment, CO2 utilization, and obtaining of valuable by-products in the industrial cultivation of microalgae is shown.

Biocementation promoted by bacteria in concrete recovery and soil stabilization

The use of intelligent and adaptable materials has been gaining ground in the construction industry, due to the ecological market demand and the awareness of investing in sustainable techniques, with low energy consumption and anthropogenic emission of carbon dioxide. The development of materials and construction methods, with energy efficiency, adaptable to environmental conditions and non-polluting has become a requirement for the progress of the sector and the future of cities. Thus, the objective of this bibliographic review is to provide an overview of the application of biocementing promoted by bacteria in the recovery of structures and soil stabilization. This technique uses minerals resulting from bacterial metabolic activities, which occur at room temperature, such as microbiologically induced calcium carbonate precipitation (MICP), to produce cementitious materials with structural functionalities, durability and without harming the environment. Several applications of this process have been proposed in civil engineering, such as the bioconcrete in the remediation of fissures, in the restoration of stones cultural heritage and in the improvement of the physical-mechanical properties of the soil, changing its resistance and permeability. Understanding how this biotechnology can change current construction strategies and solutions, integrating nature-based systems into construction projects, will be discussed in this study.

Investigation of the process of low-temperature canning of turkey meat in an environment of carbon dioxide

In recent years for refrigerated processing of poultry, development and introduction of different apparatuses operating on the principle of the direct contract with carbon dioxide have been conducted. The disadvantages of the used contact apparatuses operating using carbon dioxide are: relatively low output, increased consumption of CO2, its insufficiently effective application. In the paper the construction and the principle of the apparatus operation for refrigerated processing of dead turkeys, the construction of which allows compensating these disadvantages, were presented. For the purpose of realisation of the developed apparatus in the industry, the specialists of Kemerovo State University at the Department of “Heating Venting Air Conditioning” developed an acting model of the apparatus and studied the modes of its operation. In the course of the apparatus operation, the time of refrigerating processing of turkey was determined; consumption of carbon dioxide with different masses of poultry and modes of the apparatus operation was defined. The proposed apparatus for refrigerated processing of poultry with carbon dioxide possesses improved productivity, provides a decrease in the consumption of carbon dioxide combined with its more effective application.

Energy expenditure in COVID-19 mechanically ventilated patients: A comparison of three methods of energy estimation.

BackgroundIndirect calorimetry (IC) is the gold standard for measuring resting energy expenditure. Energy expenditure (EE) estimated by ventilator‐derived carbon dioxide consumption (EEVCO2) has also been proposed. In the absence of IC, predictive weight‐based equations have been recommended to estimate daily energy requirements. This study aims to compare simple predictive weight‐based equations with those estimated by EEVCO2 and IC in mechanically ventilated patients of COVID‐19.MethodsRetrospective study of a cohort of critically ill adult patients with COVID‐19 requiring mechanical ventilation and artificial nutrition to compare energy estimations by three methods through the calculation of bias and precision agreement, reliability, and accuracy rates.ResultsIn 58 mechanically ventilated patients, a total of 117 paired measurements were obtained. The mean estimated energy derived from weight‐based calculations was 2576 ± 469 kcal/24 h, as compared with 1507 ± 499 kcal/24 h when EE was estimated by IC, resulting in a significant bias of 1069 kcal/day (95% CI [−2158 to 18.7 kcal]; P < 0.001). Similarly, estimated mean EEVCO2 was 1388 ± 467 kcal/24 h when compared with estimation of EE from IC. A significant bias of only 118 kcal/day (95% CI [−187 to 422 kcal]; P < 0.001), compared by the Bland‐Altman plot, was noted.ConclusionThe energy estimated with EEVCO2 correlated better with IC values than energy derived from weight‐based calculations. Our data suggest that the use of simple predictive equations may potentially lead to overfeeding in mechanically ventilated patients with COVID‐19.

Progress in the Use of Biosourced Phenolic Molecules for Electrode Manufacturing

In the era of renewable technologies and clean processes, carbon science must adapt to this new model of a green society. Carbon materials are often obtained from petroleum precursors through polluting processes that do not meet the requirements of sustainable and green chemistry. Biomass is considered the only renewable source for the production of carbon materials, as the carbon in biomass comes from the consumption of carbon dioxide from the atmosphere, resulting in zero net carbon dioxide emissions. In addition to being a green source of carbon materials, biomass has many advantages such as being a readily available, large and cheap feedstock, as well as the ability to create unique carbon-derived structures with well-developed porosity and heteroatom doping. All these positive aspects position biomass-derived carbon materials as attractive alternatives in multiple applications, from energy storage to electrocatalysis, via adsorption and biosensors, among others. This review focuses on the application of phenolic resins to the production of electrodes for energy storage and the slow but inexorable movement from petroleum-derived phenolic compounds to biosourced molecules (i.e., lignins, tannins, etc.) as precursors for these carbon materials. Important perspectives and challenges for the design of these biosourced electrodes are discussed.

Ultra-efficient synthesis of bamboo-shape porphyrin framework for photocatalytic CO2 reduction and consecutive C-S/C-N bonds formation

The consumption of carbon dioxide (CO2) for direct solar fuel productions and synthesis of fine solar chemicals are gaining leading significance due to the shortage of fossil-fuel and global warming worldwide. Therefore, herein, we report the synthesis and development of solar light harvesting bamboo-shape magnesium tetraphenyl porphyrin based framework (Mg-TPPBF) photocatalyst. The development of Mg-TPPBF photocatalyst-biocatalyst bonded system as a solar light harvesting photocatalyst functions in a extremely efficient manner, increasing to high regeneration of NADH (73.9%), followed by its utilization in exclusive amount of formic acid (HCOOH) production (197.2 μmol) from CO2. The Mg-TPPBF photocatalyst also enables in consecutive C-S/C-N bonds formation with high yield (~96–99%) and selectivity (~97–99%) under solar light with excellent reusability. The current research work highlights the enlargement and application of Mg-TPPBF photocatalyst for direct solar fuel production from CO2 and fine solar chemical synthesis.

Does eutrophication enhance greenhouse gas emissions in urbanized tropical estuaries?

Estuaries are considered as important sources of the global emission of greenhouse gases (GHGs). Urbanized estuaries often experience eutrophication under strong anthropogenic activities. Eutrophication can enhance phytoplankton abundance, leading to carbon dioxide (CO2) consumption in the water column. Only a few studies have evaluated the relationship between GHGs and eutrophication in estuaries. In this study, we assessed the concentrations and fluxes of CO2, methane (CH4) and nitrous oxide (N2O) in combination with a suite of biogeochemical variables in four sampling campaigns over two years in a highly urbanized tropical estuary in Southeast Asia (the Saigon River Estuary, Vietnam). The impact of eutrophication on GHGs was evaluated through several statistical methods and interpreted by biological processes. The average concentrations of CO2, CH4 and N2O at the Saigon River in 2019–2020 were 3174 ± 1725 μgC-CO2 L−1, 5.9 ± 16.8 μgC-CH4 L−1 and 3.0 ± 4.8 μgN-N2O L−1, respectively. Their concentrations were 13–18 times, 52–332 times, and 9–37 times higher than the global mean concentrations of GHGs, respectively. While CO2 concentration had no clear seasonal pattern, N2O and CH4 concentrations significantly differed between the dry and the rainy seasons. The increase in eutrophication status along the dense urban area was linearly correlated with the increase in GHGs concentrations. The presence of both nitrification and denitrification resulted in elevated N2O concentrations in this urban area of the estuary. The high concentration of CO2 was contributed by the high concentration of organic carbon and mineralization process. GHGs fluxes at the Saigon River Estuary were comparable to other urbanized estuaries regardless of climatic condition. Control of eutrophication in urbanized estuaries through the implantation of efficient wastewater treatment facilities will be an effective solution in mitigating the global warming potential caused by estuarine emissions.

Functional measures as potential indicators of down-the-drain chemical stress in freshwater ecological risk assessment.

Conventional ecological risk assessment (ERA) predominately evaluates the impact of individual chemical stressors on a limited range of taxa, which are assumed to act as proxies to predict impacts on freshwater ecosystem function. However, it is recognized that this approach has limited ecological relevance. We reviewed the published literature to identify measures that are potential functional indicators of down‐the‐drain chemical stress, as an approach to building more ecological relevance into ERA. We found wide variation in the use of the term “ecosystem function,” and concluded it is important to distinguish between measures of processes and measures of the capacity for processes (i.e., species' functional traits). Here, we present a classification of potential functional indicators and suggest that including indicators more directly connected with processes will improve the detection of impacts on ecosystem functioning. The rate of leaf litter breakdown, oxygen production, carbon dioxide consumption, and biomass production have great potential to be used as functional indicators. However, the limited supporting evidence means that further study is needed before these measures can be fully implemented and interpreted within an ERA and regulatory context. Sensitivity to chemical stress is likely to vary among functional indicators depending on the stressor and ecosystem context. Therefore, we recommend that ERA incorporates a variety of indicators relevant to each aspect of the function of interest, such as a direct measure of a process (e.g., rate of leaf litter breakdown) and a capacity for a process (e.g., functional composition of macroinvertebrates), alongside structural indicators (e.g., taxonomic diversity of macroinvertebrates). Overall, we believe that the consideration of functional indicators can add value to ERA by providing greater ecological relevance, particularly in relation to indirect effects, functional compensation (Box 1), interactions of multiple stressors, and the importance of ecosystem context. Environ Assess Manag 2022;18:1135–1147. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Chemical denudation in a small mountainous coastal river in the tropics: Insights from Kali River, Southwestern India

A study was conducted for the first time to understand the geochemical processes controlling the chemistry of the Kali River in tropical southwestern India and to determine its chemical denudation and net carbon dioxide consumption. The samples were collected from the source to the mouth of the river (15 stations) during monsoon (July 2018), post-monsoon (December 2018), and pre-monsoon (May 2019) seasons. The catchment experiences intense chemical weathering on account of heavy rainfall accompanied by runoff during the summer monsoon. Seasonal variations in silicate weathering processes are significantly controlled by runoff, and their rates are proportional to the discharge. The annual chemical denudation rate (CDR) calculated exclusively from the upstream catchment that are dominated by silicate rocks estimated to be 48.2 tons/km2/yr with a silicate weathering rate (SWR) of 41.3 tons/km2/yr and carbonate weathering rate (CWR) of 6.9 tons/km2/yr. The CDR is two times higher than the global mean average rate. The mean CO2 consumption rate (CCR) for silicate weathering is 2.9 × 105 mol. km−2 y−1, which is three-fold higher than the global average. Silicate rock weathering intensity (Re) values indicate the formation of the gibbsite. The Re does not show variations from upstream to downstream, implying the rapid transport of weathered material from the river catchment area. Intense rain, runoff, and temperature are the dominant climatic factors that accelerate weathering in the study area. This underscores the significance of small mountainous coastal rivers as drivers of intense chemical weathering in humid tropical environments, which removes the atmospheric CO2. This study adds to the existing database on chemical weathering and associated fluxes in granitic catchments across the globe.

MoBiMS: A modular miniature mass analyzer for the real-time monitoring of gases and volatile compounds in biological systems

Living organisms constantly interact with their environment, including through the exchange of gases. Respiration and the release and uptake of volatile organic compounds (VOCs) create dynamic microenvironments in biological systems. Studying the kinetics of volatiles in biological systems requires expensive instruments, and data analysis is challenging. Therefore, we aimed to design a minimal analytical device for measuring the composition of gaseous mixtures in real-time. We built the ‘Modular Biological Mass Spectrometer’ (MoBiMS) from 3D-printed parts and custom sensors to fit a wide array of experimental set-ups. We tested the chemical detection range and temporal resolution of the MoBiMS employing pure compounds and complex biological samples. Compounds with a higher than 0.4 mmHg vapor pressure and a molecular weight up to 154 g/mol were reliably sensed within seconds. The generated electron impact (EI) spectra were directly comparable with standard databases like the NIST EI library. Under a direct analysis approach, the MoBiMS identified the characteristic odor of banana (Musa sp.), that is, isoamyl acetate; tracked the dynamics of CO2 release while the Alka-Seltzer® reaction occurred; and showed the kinetics of the transient production and consumption of carbon dioxide during photosynthesis. MoBiMS also discriminated between volatile compounds ions coming from tobacco (Nicotiana benthamiana) leaves and the surrounding air through untargeted analysis. The small footprint of the MoBiMS and its low energy consumption (242 W) facilitate in situ analyses, moreover an additional gas supply is not necessary with EI ionization. The MoBiMS is easy to assemble, and its construction and operation are very cost-efficient compared to commercial devices. The analytical performance of the MoBiMS is suitable for real-time studies of biological systems, environmental monitoring, and medical diagnostics.

SIMULATION OF A TECHNOLOGICAL SCHEME IN OBTAINING HEAT-INSULATING MATERIALS ON THE BASIS OF AIROGELS

The analysis of technologies for obtaining inorganic aerogels based on silicon dioxide as heat-insulating materials has been carried out. The description of the process of supercritical drying for obtaining highly efficient heat-insulating materials based on inorganic aerogels is given, the main technological parameters are given. The technological scheme of the main stage of obtaining aerogels is presented and described - the process of supercritical drying of an industrial plant located in LLC Niagara, Shchelkovo, in the development of which the authors took part (there is a patent). For this production, a mathematical model has been developed using the CHEMCAD software package, which makes it possible to build material and heat balances of both individual devices and the technological scheme as a whole. The technological scheme of the drying process in the environment of supercritical carbon dioxide includes the following devices: high-pressure autoclaves (70 l), compressor, separator, heat exchanger, refrigerant pump, and condenser. The article presents the basic equations for calculating the operation parameters of the above equipment (power, enthalpy, pressure, etc.), as well as the equations used in calculating economic costs (for raw materials, electricity, etc.). Calculations were carried out according to the equations of the model built in the CHEMCAD environment and the influence of various parameters on the energy and resource saving of the process was studied. The effect of isopropyl alcohol on the consumption of carbon dioxide was calculated. A dependence of the temperature after throttling the flow of supercritical carbon dioxide on the content of the solvent isopropyl alcohol in it is constructed, illustrating the possibility of reducing the amount of heat supplied at the initial stages of the drying process. Based on the data obtained, an analysis of the energy and economic costs of the supercritical drying process was carried out. On the basis of a mathematical model, an energy- and resource-efficient method of technological design of the supercritical drying process is determined. A decrease in the energy and economic costs of the technological scheme using heat after compression has been established.

ОСОБЕННОСТИ МЕХАНИЗИРОВАННОЙ НАПЛАВКИ В СРЕДЕ УГЛЕКИСЛОГО ГАЗА

This article discusses the issues of mechanized surfacing in a carbon dioxide environment. A method for calculating the parameters for mechanized surfacing in a carbon dioxide environment is presented: tables are presented for selecting parameters and formulas for calculating, namely: average values of allowances for turning shafts, average values of allowances for grinding shafts, selection of the electrode wire diameter, limits for changing the parameters of the surfacing mode, welding current strength and corresponding arc voltage, electrode reach, carbon dioxide consumption, internal diameter of the wire feed spiral depending on the diameter of the electrode wire.