Monoxide CO Research Articles

Ignition of Coal Microparticles by Laser Pulses of The Second Harmonic of a Ndodymium Laser in the Q-Switched Regime

The ignition of pelletized samples of hard coals of the long-flame gas (DG), gas (G), fat (L), coke (K) grades with particle sizes ≤63 μm by laser pulses (λ = 532 nm, τi = 10 ns) was studied. When the critical radiation energy density Hcr(1), specific for each grade of coal, is exceeded, an optical breakdown occurs and a dense plasma with a continuous emission spectrum is formed. As the plasma expands and rarefies, the spectra show the emission of carbon ions CII, excited nitrogen atoms N, excited carbon molecules C2, and carbon monoxide CO. The plasma glow intensity peaks at the end of the laser pulse, and the glow relaxation time is ~1 μs. The plasma glow amplitude increases nonlinearly with increasing laser pulse energy density. At radiation energy density H ≥ Hcr(2), specific for each grade of coal, thermochemical reactions are initiated in the volume of microparticles and coal particles are ignited in a submillisecond time interval.

Molecular cloud matching in CO and dust in M33

This study is aimed to contribute to a more comprehensive understanding of the molecular hydrogen distribution in the galaxy M33 by introducing novel methods for generating high angular resolution (18.2″, equivalent to 75 pc for a distance of 847 kpc) column density maps of molecular hydrogen (NH2). M33 is a local group galaxy that has been observed with Herschel in the far-infrared (FIR) wavelength range from 70 to 500 μm. Previous studies have presented total hydrogen column density maps (NH), using these FIR data (partly combined with mid-IR maps), employing various methods. We first performed a spectral energy distribution (SED) fit to the 160, 250, 350, and 500 μm continuum data obtain NH, using a technique similar to one previously reported in the literature. We also use a second method which involves translating only the 250 μm map into a NH map at the same angular resolution of 18.2″. An NH2 map via each method is then obtained by subtracting the H I component. Distinguishing our study from previous ones, we adopt a more versatile approach by considering a variable emissivity index, β, and dust absorption coefficient, κ0. This choice enables us to construct a κ0 map, thereby enhancing the depth and accuracy of our investigation of the hydrogen column density. We address the inherent biases and challenges within both methods (which give similar results) and compare them with existing maps available in the literature. Moreover, we calculate a map of the carbon monoxide CO(1 − 0)-to-molecular hydrogen (H2) conversion factor (XCO factor), which shows a strong dispersion around an average value of 1.8 × 1020 cm−2/(K km s−1) throughout the disk. We obtain column density probability distribution functions (N-PDFs) from the NH, NH2, and NH I maps and discuss their shape, consisting of several log-normal and power-law tail components.

Modeling air pollution around major dumpsites in Lagos State using geospatial methods with solutions

Air pollution is gradually becoming a major health concern globally and Nigeria is especially susceptible to air pollution Available data indicates that vehicular traffics, industries, wildfire and biomass burning are significant sources of air pollutants such as Particulate Matter PM, Carbon Monoxide CO, Nitrogen Dioxide NO2, Sulphur Dioxide SO2 and Volatile Organic Compounds VOCs in the air in Lagos State. The aim of this study is to perform geospatial modelling of air pollution around Olusosun and Solous dumpsites in Lagos State. The study analyses, assesses, and predicts air pollution emission in these dumpsites and examines their possible health impact on residents. Using both ground and satellite-based data, different GIS techniques were used to model this pollution concentration. These methods include Kriging, Regression, and Landfill Gas Emissions Model (LANDGEM) which helps to analyse, model and predict the air pollutant levels around these dumpsite. The average pollution level of Particulate Matter with a diameter that is 2.5 micrometers (PM2.5) in Olusosun was 94.29 μg/m3 while those in Solous was 94.12 μg/m3 over a 24 h period. This is way above the Air Quality Guideline recommended by the WHO which is 15 μg/m3 over a 24 h period. This is similar to the high pollution level of NO2 which was 237.64 μg/m3 in Olusosun and 255.84 μg/m3 in Solous as against the WHO Air Quality Guideline of 25 μg/m3 over a 24 h period. SO2 level is also varyingly high in Olusosun and Solous. The reading of 109.27 μg/m3 in Olusosun is considerably high as compared to the reading of 43.82 μg/m3 in Solous. However, both readings are relatively higher than the Air Quality Guideline recommended by the WHO which was 40 μg/m3. The CO air quality level of 0.55 mg/m3 in Olusosun and 0.52 mg/m3 in Solous is within the accepted level of the Air Quality Guideline recommended by the WHO. This shows that CO is not a pollution threat in the major dumpsites in Lagos. This is similar to the readings of PM5 and PM10 which are within the WHO Air Quality Guidelines over a 24 h period. The Moderate Resolution Imaging Spectroradiometer (MODIS) data shows a trend of increasing concentration of PM2.5 over the 5 study months due to an increase in the quantity of waste disposal, which shows that high waste disposal is directly proportional to high level of PM2.5. It is recommended that living farther (more than 15 km) away from the dumpsites can reduce the high risk of air pollution and its related diseases for residents. Also, there is need for proper incineration and maintenance of waste to reduce the level of air and other pollutants in and around the dumpsites.

Comprehensive Assessment of Air, Soil, and Water Pollution for Environmental Health in Al-Hai City, Iraq

Sustainability has evolved into a broad phrase that includes practically every aspect of life on the Earth, from local to global, and over different periods. Sustainable biological systems include healthy, long-lived forests and wetlands. This paper aimed to study and measure pollution indicators in the Al-Hai city center's air, soil, and water in Wasit province, located at Coordinates (32.1742 N° and 46.0433 E°). The data for Al-Hai city's ambient air pollutants (CO, NO, NO2, H2S, SO2, and CO2) that considered air pollution was recorded for the date (12-13/12/2021). The Maximum values for the concentration of carbon monoxide CO and sulfur dioxide SO2 were 1.019 ppm and 0.0321 ppm, respectively. The water and sediment samples were collected in December 2021, and all samples were analyzed in the laboratory. Heavy elements (Cd, Pb, As, and Hg) were measured in soil and water. The samples were collected and taken from two stations in the Gharraf River of Al-Hai city in Wasit province to investigate the potential for environmental damage caused by these components in this region. This study will be conducted at two stations (North and South of Al-Hai city center) beginning in December 2021. In the south station, all heavy elements showed exponential growth in water and sediment samples, but concentrations in the north station were low. The highest value recorded in this study was for the pb concentration in the soil samples taken from the main street, which was 31.9 ppm.

Computational and Experimental Research on the Influence of Supplied Gas Fuel Mixture on High-Temperature Fuel Cell Performance Characteristics

Currently, the process of creating industrial installations is associated with digital technologies and must involve the stage of developing digital models. It is also necessary to combine installations with different properties, functions, and operational principles into a single system. Some tasks require the use of predictive modeling and the creation of “digital twins”. The main processes during the fuel cell modeling involve electrochemical transformations as well as the movement of heat and mass flows, including monitoring and control processes. Numerical methods are utilized in addressing various challenges related to fuel cells, such as electrochemical modeling, collector design, performance evaluation, electrode microstructure impact, thermal stress analysis, and the innovation of structural components and materials. A digital model of the membrane-electrode unit for a solid oxide fuel cell (SOFC) is presented in the article, incorporating factors like fluid dynamics, mass transfer, and electrochemical and thermal effects within the cell structure. The mathematical model encompasses equations for momentum, mass, mode, heat and charge transfer, and electrochemical and reforming reactions. Experimental data validates the model, with a computational mesh of 55 million cells ensuring numerical stability and simulation capability. Detailed insights on chemical flow distribution, temperature, current density, and more are unveiled. Through a numerical model, the influence of various fuel types on SOFC efficiency was explored, highlighting the promising performance of petrochemical production waste as a high-efficiency, low-reagent consumption fuel with a superior fuel utilization factor. The recommended voltage range is 0.6–0.7 V, with operating temperatures of 900–1300 K to reduce temperature stresses on the cell when using synthesis gas from petrochemical waste. The molar ratio of supplied air to fuel is 6.74 when operating on synthesis gas. With these parameters, the utilization rate of methane is 0.36, carbon monoxide CO is 0.4, and hydrogen is 0.43, respectively. The molar ratio of water to synthesis gas is 2.0. These results provide an opportunity to achieve electrical efficiency of the fuel cell of 49.8% and a thermal power of 54.6 W when using synthesis gas as fuel. It was demonstrated that a high-temperature fuel cell can provide consumers with heat and electricity using fuel from waste from petrochemical production.

Real-time air quality monitoring based on locally developed unmanned aerial vehicle and low-cost smart electronic device

This article deals with the development of real-time air quality monitoring based on Unmanned Aerial Vehicles (UAVs) and low-cost Internet of Things (IoT) devices. This investigation aims to design and develop an UAV-based platform that can monitor a large number of air pollutants in real-time with high spatial and temporal resolution. The proposed environmental monitoring system consists of five main elements, namely the UAV, sensors, data storage module, programmable card, and IoT communication module. Estimated pollutants such as particulate matter (PM2.5) and toxic gases (carbon monoxide CO, nitrogen dioxide NO2, and carbon dioxide CO2) are detected by low-cost sensors. The ZigBee wireless protocol is used for communication between the PC and UAV. This work is carried out to assess the air quality in urban areas, given the heavy road traffic and the emissions of some companies. The data analyzed were collected from December 2, 2022 to January 3, 2023, in two major cities of Cameroon, Douala and Kribi. The periodic average values of the detected pollutants are 222 ± 22 μg/m3 and 85.7 ± 8.6 μg/m3 for PM2.5, 560.8 ± 1.0 ppm and 555.6 ± 1.0 ppm for CO2, 4.2 ± 0.2 ppm and 0.7 ± 0.1 ppm for NO2, and 27.6 ± 2.8 ppm and 4.5 ± 0.5 ppm for CO in Douala and Kribi respectively. This made it possible to have an air quality index (AQI) of 444.2 for Douala City and 171.3 for Kribi City. These high values indicate poor air quality during the measurement period.

ALMA survey of a massive node of the Cosmic Web at z ∼ 3

Submillimeter surveys toward overdense regions in the early Universe are essential for uncovering the obscured star formation and the cold gas content of assembling galaxies within massive dark matter halos. In this work, we present deep ALMA mosaic observations covering an area of ∼2′×2′ around MUSE Quasar Nebula 01 (MQN01), one of the largest and brightest Ly-α emitting nebulae discovered thus far; it surrounds a radio-quiet quasar at z ≃ 3.25. Our observations target the 1.2 and the 3 mm dust continuum as well as the carbon monoxide CO(4–3) transition in galaxies in the vicinity of the quasar. We identify a robust sample of 11 CO-line-emitting galaxies (including a closely separated quasar companion) that lie within ±4000 km s−1 of the quasar systemic redshift. A fraction of these objects were missed in previous deep rest-frame optical/UV surveys, which highlights the critical role of (sub)millimeter imaging. We also detect a total of 11 sources revealed in the dust continuum at 1.2 mm; six of them have either high-fidelity spectroscopic redshift information from rest-frame UV metal absorptions or the CO(4–3) line that places them in the same narrow redshift range. A comparison of the CO luminosity function and 1.2 mm number count density with those of the general fields points to a galaxy overdensity of δ > 10. We find evidence of a systematic flattening at the bright end of the CO luminosity function with respect to the trend measured in blank fields. Our findings reveal that galaxies in dense regions at z ∼ 3 are more massive and significantly richer in molecular gas than galaxies in fields, which enables a faster and accelerated assembly. This is the first in a series of studies aimed at characterizing one of the densest regions of the Universe found so far at z > 3.

Measuring the concentrations of some gaseous air pollutants and dust particles in the western city of Hamzah in Iraq

This research concentrates on studying and analyzing the spatial and temporal variation of the concentrations of air pollutants in the Hamzah-western city during the four seasons of the year 2022 by studying the concentrations of gaseous pollutants in the air, such as NO2, SO2, CO, CO2, and O3, as well as measuring the concentrations of dust particles suspended in the air, such as PM2.5 and PM10. The number of sampling sites reached six, distributed into five different sectors (industrial, residential, transport, agricultural, and a mixed sector combining industry and transportation) in order to show the discrepancies in the concentrations of pollutants and explain their causes. The results of in situ measurements and laboratory analyses showed that there is a spatial and temporal variation in the concentrations of air pollutants. The highest concentrations of carbon monoxide CO, carbon dioxide CO2, and sulfur dioxide SO2 were recorded in sector 1 and during the summer season at concentrations of 38.5, 337, and 2.9 ppm, respectively. While the highest concentrations of nitrogen dioxide (NO2) were recorded in sector (2) with a concentration of 0.65 ppm, and all those concentrations were outside the permissible limits, the lowest concentrations were recorded for gases in sector (6), which covered all the study semesters. As for the concentrations of suspended dust particles in their sizes (PM2.5 and PM10), the highest concentrations were recorded in Sector (2), during all seasons of the study, and at 383.81 and 389.38 ppm concentrations, respectively. While the lowest concentrations of suspended particles of both sizes were recorded in Sector 6, a value of 119.65 ppm was recorded for PM2.5 minutes and 115.65 ppm for PM10 minutes. Thus, all their values during the study period were greater than the permissible limits.

Spatio-temporal analysis of deaths from carbon monoxide poisoning in Iran between 2011 and 2018: An ecological study.

Mortality caused by carbon monoxide every year threatens the lives of Iranian people, whose spatial and temporal distribution is not known for formulating prevention policies and interventions. This study was conducted to determine the trend of mortality rate changes due to carbon monoxide CO poisoning by Spatio-temporal analysis in Iran from 2011 to 2018. An ecological study was conducted based on data from the reports at the National Center for Statistics of Iran for 8 years from 21 March 2011 to 21 March 2018. The number of deaths due to CO poisoning and the annual mortality rates of CO poisoning per 100,000 populations were calculated. To determine the geographical and temporal distribution of death caused by carbon monoxide, spatiotemporal statistical analysis was used. A total of 6078 deaths were reported due to CO poisoning 4497 deaths were male (74%) and 1596 were female (26%) from 2011 to 2018. Both sexes'mortality rate due to CO poisoning was 1.26 from 2011 to 0.91 in 2018. According to the results, the overall male-to-female ratio was 2.8. The mortality rate due to CO Poisoning had a decreasing trend. However, this trend did not have a linear trend (p = 0.37). The highest mortality due to CO poisoning was seen in the northern and western provinces of Iran. Our results showed that the mortality rate due to CO poisoning had a decreasing trend during the understudied period. Also, most of the deaths due to CO poisoning occurred in the northern and western provinces of Iran. So, designing prevention programs as well as increasing people's awareness in these regions is recommended.

Identification of places with deteriorated air quality in city of Žilina in relation to road transport

The aim of the research is to identify places with deteriorated air quality in the selected city. After an analytical analysis of the data, it is possible to propose steps that can be used to actively contribute to the reduction of air pollution, especially due to road traffic. Places where deteriorated air quality was identified were identified on the basis of practical measurements. Given that the measurement route was designed in a built-up area of the city with a large number of pedestrians, the research was primarily focused on the identification of particulate matters (PM) and the concentration of carbon monoxide CO. The measurements were performed repeatedly on a pre-defined route. The measurements were carried out repeatedly during the morning rush hour when traffic was congested on the roads. Based on the processing and evaluation of the measurements, the sections where increased values of individual emissions were recorded were determined. In this way, it is possible to precisely identify places where air quality deteriorates. The research conclusions provide support for planning the optimization of air quality management policies towards the creation of sustainable cities. The research results present the possibilities of identifying problematic sections from the point of view of emissions production. Critical places with regard to the production of emissions can be connected to places where a permanently increased movement of vehicles is observed.

Biogas as an additive to compressed natural gas for vehicle engines

The article considers the possibility of using biogas for vehicle engines, as an additive to compressed natural gas, and gives the results of experimental studies of environmental indicators and fuel efficiency of a vehicle equipped with a gasoline engine and converted to work on a mixture of biogas and compressed natural gas. Currently, there are many vehicles in operation that operate without feedback on the content of oxygen in the exhaust gases, they run on gasoline and gas motor fuels, in view of this, the results of these studies are very relevant. It has been proven that the use of biogas as motor fuel for vehicle engines reduces the energy dependence on petroleum fuels and reduces emissions of harmful substances in the exhaust gases of the vehicle engine, and the use of biogas as an additive to compressed natural gas will provide an opportunity not to spend additional resources for its purification. The use of biogas as a motor fuel confirms the possibility of its use in traditional constructions of vehicle engine power systems. With simple, reliable and proven production technologies, biogas can become a cost-effective and efficient type of fuel obtained from renewable sources. In this way, it is possible to satisfy these needs by using alternative types of fuels, one of these types of fuels is biogas, which is obtained in the process of anaerobic decomposition of organic waste. Biogas consists of methane CH4, carbon dioxide CO2, small amounts of carbon monoxide CO, hydrogen H2, nitrogen N2, oxygen O2, water vapor H2O and hydrogen sulfide H2S. The possibility of using a mixture of fuels, namely biogas as an additive to compressed natural gas, is substantiated. A comparative analysis of the fuel-economical and environmental performance of the vehicle engine in the modes of the European urban driving cycle was performed while the engine was running on compressed natural gas, a mixture of biogas and compressed natural gas, and liquid petroleum fuel gasoline brand A-92

Reducing the Harmful Exhaust Emissions from the Diesel Engine of the Tractor CASE JX75T by using the EFWP Filter at Different Engine Speeds

In this investigation, the influence of using the EFWP filter on the tractor exhaust emissions was determined. A Water and paper filter is a filter designed to operate as a filter for the exhaust for the reduction of the harmful gas (CO, CO2, NOx, and HC) emission from the engine of the tractor. Emissions experiments were carried out on CASE JX75T tractor at different engine speeds are 750, 1000, 1250, 1500, 1750, 2000, and 2250 rpm. All engine speed of the tractor underwent experimentation before the installation of the EFWP filter and after installation it. The noises and Bsfec also were measured when the two cases. Each engine speed was tested for approximately 20 minutes in two cases. The results showed a significant (P≤0.05) decreasing in carbon monoxide CO (51.40%), carbon dioxide CO2 (25%), nitrogen oxides NOx (43.43%) and hydrocarbons HC (60.98%) emissions and also, the noises reduced by 25.38% and there was no significant increase in the BSFC (5.34% only) after the EFWP filter was put in the tractor exhaust. The results also showed that increasing the engine speed from 750 to 2250 rpm led to significant increases in CO2, NOx, and HC emissions, while decreased the CO emission. Also, the increased by a percentage of 155.88 and 159.38 % in the case using the EFWP filter and without using it (the ordinary case) respectively. Using the EFWP filter reduced the noises not overridden internationally permitted standards (65 dB).

Effects of Nozzle Diameter and Holes Number on the Performance and Emissions of a Gasoline Direct Injection Engine

The goal of the current study is to estimate how a gasoline direct injection (GDI) engine's performance and emissions are affected by the fuel injector nozzle diameter and hole number of its injectors. A thermodynamic mathematical modelling has been created utilizing a software program written in the MATLAB language to simulate the two-zone combustion process of a four-stroke direct injection engine running on gasoline at (Rotation Engine Speed 3000 revolution per minute (rpm), 40 MPa injection pressure, compression ratio 9.5, and spark timing 145°). The first law of thermodynamics, equation of energy, mass conserving, equation of state, and mass fraction burned were all used in the creation of the software program. The study was carried out at five different nozzle diameters (0.250, 0.350, 0.450, 0.550, and 0.650 mm) and nozzle hole numbers (4,6,8,10,12). The results show that the GDI engine's performance and emissions are significantly influenced by variations in nozzle hole diameter and number. It was shown that engine power, heat transfer, cylinder pressure, and temperature increased with increasing nozzle hole diameter and number of nozzle holes and the maximum value was seen with nozzle hole diameter 0.650 mm and (12) holes. The lowest value for the nozzle hole diameter and number of holes was found to be 0.250 mm and 4 nozzle holes, which resulted in the lowest emissions of carbon monoxide CO and nitrogen monoxide NO. The study was also conducted for different operating conditions (Rotation Engine speed of 1000, 2000, 3000, 4000, 5000 rpm ,35 MPa injection pressure , compression ratio of 11.5 , and spark timing of 140° ) and the same nozzle diameters and nozzle holes number mentioned previously to estimate the maximum values for temperature, pressure, power , heat transfer and emissions . The results of the second part of the study showed that the highest of maximum values of temperature, pressure, and emissions were at of 1000 rpm, a nozzle diameter of 0.650 mm, and (12) holes. The highest values for maximum power at 4000 rpm, a nozzle diameter of 0.650 mm and (12) holes, while the highest maximum values for heat transfer are at 5000 rpm, a diameter of 0.65mm and (12) holes.

МОНИТОРИНГ ДОРОЖНОЙ БЕЗОПАСНОСТИ В ЧРЕЗВЫЧАЙНЫХ УСЛОВИЯХ РАСПРОСТРАНЕНИЯ СМОГА ТОРФЯНОГО ПОЖАРА

The physical phenomenon of smog formation from burning peat bogs and its persistent air pollution on the highway is investigated. It is shown that particulate smog particles of small sizes PM10 and PM2.5 are capable, as on condensation nuclei, of creating optically dense aerosol fogs and, thereby, reducing the visibility range on the roadway to 50 meters or less, significantly increasing the risk of traffic accidents. It is proved that, together with carbon monoxide CO, smog saturates the air with pollutants to dangerous concentrations that can significantly weaken the reflex reactions of drivers to changing traffic conditions. In combination, this leads to an emergency situation, accompanied by a transport collapse, requiring the involvement of forces and means of emergency response.

Universal “Plug and Play” Real-Time Entire Automotive Exhaust Effluents, Industry Vents and Flue Gas Emissions Liquefiers: The Game Changer Approach-Phase Two Category

Universal “Plug and Play” Real-Time Entire Automotive Exhaust Effluents, Industry Vents and Flue Gas Emissions Liquefiers: The Game Changer Approach-Phase Two Category

MODERN TECHNOLOGIES FOR INCREASING THE ENERGY AND ENVIRONMENTAL EFFICIENCY OF ENERGY PRODUCTION

The problems of energy efficiency of energy production along with improving the environmental safety of enterprises are becoming increasingly relevant. One of the ways to solve these problems is the implemention of effective technologies, which include microflare incineration technology (MIT-technology) of gaseous fuels. The use of MIT- technology, in addition to a significant reduction in harmful emissions into the atmosphere, can simultaneously increase the energy efficiency of thermal power plants.
 A significant positive effect can also be achieved by using contact energy exchange plants. A striking example of such a gas-steam plant “Aquarius” the operation of which exceeds the efficiency of gas turbine plants by 10-12% with a simultaneous significant decrease in the concentration of toxic nitrogen oxides NOx and carbon monoxide CO in flue gases.

The Effect of Flue Gas Recirculation on CO, PM and NOx Emissions in Pellet Stove Combustion

Pellet stoves are popular appliances because they are an affordable technology and because the fuel is easy to store and to use. The increasing concern for environmental issues, however, requires a continuous effort to reduce pollutant levels in the atmosphere. This experimental work focuses on flue gas recirculation (FGR) as a possible way to improve combustion and decrease the emissions of carbon monoxide CO, particulate matter PM, and nitrogen oxides NOx in order to fulfill European and Italian emission requirements, for NOx in particular. A pellet stove has been tested in several experimental sessions with and without FGR. Pollutant emissions have been measured and analyzed in terms of statistical summaries and instantaneous trends. With FGR, the average CO and PM emissions were found to be 80% and 45% lower than the corresponding emissions without FGR. Results for PM are significant since FGR reduces emissions well below the most restrictive limits enforced in Italy. The analysis of instantaneous emissions in relation to excess air indicated that FGR can considerably reduce emissions, especially at the extremities of the oxygen O2 content range. Optimal ranges of excess air, in terms of O2 in flue gas, were identified for both the tested configurations, in which CO and PM emissions are minimized. The optimal range is 8–9% without FGR, and it decreases to 5–7% with FGR. Finally, a reduction in NOx emissions by about 11% has been observed in the configuration with FGR. Although this reduction seems modest as compared to CO and PM, it is important in that it lowers the emission level to the most severe limit in Italian regulations and indicates an improved FGR system as the solution for further reduction.

Напрямки удосконалення технологій конверсії вугілля в синтетичні рідкі палива

Modern technologies for producing synthetic liquid fuels from coal include pyrolysis, hydrogenation, gasification, followed by synthesis of the final products by the Fischer-Tropsch process or via methanol. In pyrolysis, liquid fuels are obtained as by-products and their yield is usually no more than a few percent. A negative feature of hydrogenation is the formation of a significant amount (up to 40 %) of small, unreactive residue, the efficient use of which poses a significant scientific and technical challenge. The gas produced by coal gasification always contains more carbon monoxide CO than hydrogen, which is due to the need to ensure the heat balance of the process. At the same time, to be used in chemical syntheses, the hydrogen content in the gas should be several times higher than CO. To ensure the required Н2:СО ratio, part of the carbon contained in the feed coal is oxidised to carbon dioxide in an exothermic process. This improves the ratio in the resulting synthesis gas, but leads to irrational consumption of some carbon, reduces gas yield and ultimately increases the consumption factor of raw materials for the final product and worsens the technical and economic performance of the production. Therefore, obtaining additional hydrogen to improve the composition of synthesis gas is relevant. Until recently, however, the main way to produce hydrogen in industry was through the conversion of natural gas methane, which is unacceptable in today’s environment. The production of hydrogen from coke oven gas, where its content is about 60 % (by volume), by short-cycle adsorption is also unpromising, due to the several-fold decrease in coke production in Ukraine and, consequently, the almost complete absence of free coke oven gas resources. Therefore, it is important to introduce other industrial methods of hydrogen production. Keywords coal, synthetic liquid fuels, gasification, Fischer-Tropsch synthesis, hydrogen. Corresponding author: V.V. Shulga, e-mail: ko@ukhin.org.ua

ВИЗНАЧЕННЯ ЗОВНІШНІХ ШВИДКІСНИХ ХАРАКТЕРИСТИК СИЛОВОГО ОБЛАДНАННЯ ДОРОЖНІХ МАШИН

The paper deals with the issue of determining the fuel efficiency and toxicity of exhaust gases of power equipment of road machines operating in traction modes, namely, plow and plow-brush snowplows based on a pneumatic wheeled tractor. The object of research is fuel efficiency and toxicity of exhaust gases of power equipment. The purpose of the study is to experimentally determine the external speed characteristics of a 4Ч11,0 / 12,5 diesel engine (D-240, D-241, D-242, D-243 families), namely: maximum power Ne, maximum torque Mк; hourly consumption of fuel Gпал and air Gпов, specific effective fuel consumption ge; concentrations of harmful substances in the exhaust gases: carbon monoxide CO, hydrocarbon compounds CmHn, nitrogen oxides NOx and opacity N of the exhaust gases. The paper presents the results of experimental studies to determine the energy performance (maximum power Ne and maximum torque Mк) of a diesel engine (4Ч11,0/12,5 (D-242)) of power equipment; fuel efficiency indicators (hourly fuel consumption Gпал and specific effective fuel consumption ge); hourly air consumption Gпов; concentrations of harmful substances in the exhaust gases: carbon monoxide CO, hydrocarbon compounds CmHn, nitrogen oxides NOx and opacity N of the exhaust gases. Which are obtained with the position of the fuel supply control, which corresponds to the maximum fuel supply from the diesel crankshaft speed. The above indicators were determined at standard diesel fuel supply settings. Based on the obtained external speed characteristics Ne, Mк, Gпал, ge, Gпов, CO, CmHn, NOx and N, mathematical (polynomial) dependencies were determined, which are described from the speed of the diesel crankshaft, and their adequacy was checked. The studies carried out made it possible to determine the main direction of increasing fuel efficiency and reducing emissions of harmful substances of a diesel engine.

REALIZATION OF CONTINIOUSLY ROTATING DETONATION FOR SYNGAS-AIR MIXTURES

Numerical simulation of continuously rotating detonations (CRD) of stoichiometric two-fuel mixture with air has been carried out for the cylindrical annular detonation chamber (DC) of the rocket-type engine. Thesyngas (1 - α)óO + αH2, a binary mixture of hydrogen H2 and carbon monoxide CO, is taken as a fuel. The global flow structure in the DC and the detailed structure of the transverse detonation wave (TDW) front in thecontinuously rotating regime have been studied. Integral characteristics of the detonation process - the distribution of average values of static and total pressure along the length of the DC - and the value of specific impulse on the DC exit have been obtained. The regions of existence of stable CRD regime in coordinates “stagnation pressure pm - stagnation temperature Tm” in the injection manifold (receiver) have been determined. The minimal values of the DC length and radius for CRD for some regions at the pm-Tm plane have been found.