Natural Gas Content Research Articles

Energy efficiency improvements and CO2 emission reduction by CNG use in medium- and heavy-duty spark-ignition engines

This research studies the mechanism of improving energy efficiency and reducing CO2 emissions from medium- and heavy-duty spark-ignition engines by replacing gasoline fuels with natural gas. Detailed experimental analyses are conducted on a multi-cylinder research engine using 91RON, 98RON gasoline, and natural gas fuels. Under 7 key operating conditions, energy efficiency breakdown is performed for each fuel to quantify the individual impact of the fuel's carbon content, pumping work, knock tendency, and fuel enrichment. Complete engine mapping is thereafter carried out with all three fuels, and CO2 emissions are compared over the emission certification test cycle. As demonstrated by the test results, the lower carbon content of natural gas is the major contributor to CO2 emission reduction. At idle and part load conditions, engine operation on natural gas shows reduced pumping loss, improved idle stability, and thus increased fuel efficiency. At high load conditions, the greater resistance to knock allows natural gas to operate at optimal combustion phasing. At the peak power condition, the earlier combustion phasing helps to lower exhaust temperatures, thereby avoiding fuel enrichment. With proper calibration, natural gas outperforms its gasoline counterparts to produce 4% better peak power performance and emits 22.5% lower CO2 emissions.

Experimental investigation of hydrogen enriched natural gas diffusion reactions using preheated air in a hot coflow burner

The present paper analyzes experimentally the morphology of a set of non-premixed diffusion reactions of hydrogen enriched natural gas (NG). For the analysis the H2 content was varied from 0 to 100 vol.-% and the mixture issues in a co-flow at variable preheating temperatures, from ambient conditions of 25 °C and up to 400 °C. For the various NG-H2 blends the thermal power input was held constant at 0.8 kW. For processing the images, a bitmap filter was used to isolate visible flame height, visible width variations, and soot free length fraction (SFLF). The results show that visible flame height always decreases when increasing H2 content in NG at any preheating temperature. The effects of air preheating summarize as follows: for NG enriched up to 75 vol.-% H2, the visible flame height reduces when increasing the air preheating temperature from 25 °C to 200 °C, then at 300 °C the visible flame height increases when rising the air temperature up to 400 °C. For the 100% H2 non-premixed flame the visible height presents a linear trend to increase as air temperature rises. Roper's theory for non-premixed flames in circular ports correlates reaction length to air preheating temperature and fuel composition variations, however those trends neglect buoyancy and diffusion phenomena, which results in significant error on predicting the effects of hydrogen addition to NG on the reaction length. A modified correlation is proposed to predict accurately the effects of air preheating and H2 fraction on visible flame height. Finally, a multidimensional scaling analysis shows that hydrogen addition up to 50 vol.-% does not modifies the visible flame morphology significantly when compared to pure NG.

Nanostructures of coal beds in the Sherubaynurinsky section of the Karaganda basin

Purpose. To determine the thickness of thin films of coal matter in the Sherubaynurinsky area of the Karaganda basin and their effect on the physical properties of these films. Methodology. In order to calculate the thickness of the surface layer of the coal substance using our proposed formula, one needs to know the molar mass and density. We will use the well-known work where it is shown that such a characteristic as the molecular weight of coal reflects rather well the degree of metamorphism, and is also decisive for the study on the composition and structure of coal raw materials. Findings. The role of the thickness of the surface layer of coal in the course of most physical processes is shown. A thin layer of coal matter differs significantly from metals and other compounds. But it is close to the structure of higher fullerenes. One fundamental parameter, the atomic volume of the surface layer, determines all the properties of the nanostructure of this layer. Originality. For the first time, the thickness of the surface layer of the coal substance has been determined, which is two orders of magnitude greater than the thickness of pure metals. The thickness of the surface layer of higher fullerenes C96 (135 nm) is close to that for OC coal (146 nm). The average statistical structural unit of coal corresponds to higher fullerenes with the number of carbon atoms in the cluster >100, which is a unique feature of coal matter. The thickness of the surface layer of coal in the Sherubaynurinsky area of the Karaganda basin with a size of ~150200 nm was obtained. This structure is a nanostructure. In this layer, the physicochemical properties of nanomaterials occur: a change in the crystalline (supramolecular) structure of coal; a change in its electronic structure and its electrical conductivity; change in the conditions of the stress state of coal; change in the conditions of methane diffusion in coal seams and many other phenomena. Practical value. The natural gas content C0 depends linearly on the reciprocal of d(I). For coal seam k, where d(I) = 180.8 nm, it was obtained 0 = 19 m3/t. After the release of coal and gas, the average value of C0 = 216 m3/t at a seam depth of 430 m, and in the Sherubaynurinsky area C0 = 14 m3/t at an average thickness of the surface layer d(I) = 170 nm. Hence, after the explosion d(I)v = 35 nm, i.e. the layer thickness decreases by almost 5 times, leading to the formation of coal dust. We have considered only a part of the nanostructure issues: porosity and gas content, explosiveness and moisture content of coal seams, and have shown that all physical phenomena in a thin layer of coal have a dimensional dependence and determine structures unexplored until now, and phenomena studies on which are necessary for the practice of mining.

Radiological Hazard Related with Natural Radioactivity in Natural Gas Transportation—A Case Study from Poland

Activity concentration of 210Pb in black powder and gamma radiation dose rate related to natural gas transportation were discussed. As part of the research, the content of radiolead (210Pb) in black powder, spent filter containers, radon (222Rn) activity concentration in natural gas and gamma radiation dose were measured around selected points of natural gas transportation infrastructure in Poland. The content of some heavy metals was also analyzed. The average concentrations of 222Rn and 210Pb ranged from 30 to 1400 Bq/m3 and from around 450 to 16,000 Bq/kg, respectively. The external exposure to gamma radiation was low; the gamma radiation dose rate was at the level of background radiation or slightly exceeded it. The research demonstrated that the content of 210Pb in black powder is strongly related to radon concentration in natural gas, the volumetric flow rate of the transported natural gas and solid fraction content. Some black powder samples should be classified based on 210Pb content as low-radioactive waste.

Estimating water content of natural gas mixtures considering heavy hydrocarbons contribution using artificial neural networks

The accurate estimation of the water content of natural gas is the basis for proper equipment design in natural gas processing and transmission facilities. Methods for estimating the water content of natural gas have been reported based on pressure and temperature data, and the concentration of acid gases. This work aims to develop a predictive model based on artificial neural networks (ANN) to estimate the water content of natural gas, considering the contribution of heavier hydrocarbons than methane, commonly present in the rich gases, gas condensates, or liquefied petroleum gases. The novelty of the proposed model is the incorporation of natural gas richness (GPM) as an input parameter for calculating the water content of natural gas, in addition to temperature, pressure, and acid gas equivalent content. Experimental data from the literature is used in the ANN training and validation, with the help of the BigML machine learning platform to perform a multi-layer-feedforward neural network. The ANN performance showed the ability to accurately predict the water content for different gas mixtures (rich, lean, sweet, and sour gases). Comparisons with available models in the literature are performed, showing that the ANN model provides accurate estimations (AAD: < 10%).

Identification of Complex Fluid Properties in Condensate Gas Reservoirs Based on Gas–Oil Ratio Parameters Calculated by Optimization Mathematical Model

In the production development stages of volatile oil reservoirs and condensate gas reservoirs, especially in the early stages of production, the phenomenon of high gas–oil ratio often occurs. As a result, the prediction results of oil and gas are greatly deviated from the actual situation, which seriously affects the implementation of potential excavation and increases production operation for condensate gas reservoirs. Therefore, the accurate identification of condensate gas and volatile oil is the key to improve the development efficiency in condensate reservoirs. However, due to the similar geophysical logging response characteristics for condensate gas, volatile oil, and light oil reservoirs, the qualitative identification effect only based on conventional logging is not ideal. Therefore, we propose a method to calculate the gas–oil ratio by introducing gas logging information and use the gas–oil ratio quantitative calculation results to identify condensate gas and volatile oil layers. First, we establish a physical model of the formation components of the condensate gas reservoir. Based on this physical model, we establish the response equations of various logging tools and evaluate the correlation between the gas logging information and the production gas–oil ratio to establish the response equation of gas logging. Then, we comprehensively use the well logging and gas logging response equations to establish an optimization mathematical model, solve the optimization objective function, obtain the relative content of natural gas and movable oil in the formation to calculate the gas–oil ratio parameters, and finally use this calculation result of the gas–oil ratio to quantitatively identify the fluid type. The application results show that the gas–oil ratio quantitative calculation method that we proposed can calculate the gas–oil ratio parameter accurately, and the calculation results are consistent with the formation testing data, which provides technical support for the identification of complex fluid properties in condensate gas reservoirs.

CURRENT USES AND FUTURE CHALLENGES FOR ZEOLITE IN THE INDONESIAN OIL AND GAS PROCESSING INDUSTRY

Oil and gas industry uses zeolite as an adsorbent to reduce moisture content of natural gas in LNG Plant, and as catalyst to convert the heavy petroleum fractions feeds into light clean fuels in refinery.Low quality crude oil, low residual fuel demand, and an increased demands and spesifications for light products (gasoline, kerosene, and diesel oil) and petrochemical products, future challenges for utilization zeolite as cracking catalyst in refinery are encouraging.

Feasibility and viability of procuring biohydrogen from microalgae: An emerging and sustainable energy resource technology

Abstract As the world’s population is increasing at an unprecedented rate, causing a severe impact on the limited and depleting petroleum reserves by their overexploitation and consumption. It is estimated that due to increasing socioeconomic and infrastructural advancements, we have already consumed about 50% of the petroleum reserves. Furthermore, the excessive usage of fossil fuels is believed to be a potential cause of global warming and a threat to environmental sustainability. This led the researchers to explore and study renewable and carbon-neutral sources of energy, which can be optimized as per the requirement and should be economically viable. Microalgae stand out momentous and materialized as feedstock to get all that we need at a single platform. Microalgae are the primary producers that utilize Carbone dioxide CO2 and light for their growth. They can be grown in freshwater, saline water, and even in wastewaters due to their disparate biochemical metabolism. This urged microalgae to be exploited for obtaining various renewable energy-based fuels, as it has the following significant features: potential for CO2 fixation; high biomass growth rate; its capacity to store carbon in lipids and carbohydrates to produce biofuels (bioethanol, biodiesel, biohydrogen, and biomethane). Recently, Hydrogen have gained interest as one of the most environmental friendly fuel. Hydrogen has numerous merits as compared with others fuel. The range of energy content is 120–142 MJ/Kg and it has high content (142 MJ/kg) as comparing with energy content of gasoline (47 MJ/kg), methane (56 MJ/kg), and natural gas (54 MJ/kg) while, the energy density is 8.5–10.1MJ/L. Furthermore, the yield is 92–485 mL/gVS and cetane number 50-53. This mini review provides an insight about the processes of biophotolysis, and fermentation utilized in the production of biohydrogen utilizing microalgae. It will incorporate the recent developments and innovations in biohydrogen production using microalgae. It will also give an overview of the challenges encountered in the production routes and the future perspectives.

Pore structure evolution of lacustrine organic-rich shale from the second member of the Kongdian formation in the Cangdong Sag, Bohai Bay Basin, China

Pyrolysis experiments were conducted on lacustrine organic-rich shale from Cangdong Sag in Bohai Bay Basin, China, to investigate the impact of hydrocarbon generation on shale pore structure evolution. Thermal evolution is found to control the transformation of organic matter, hydrocarbon products characteristics, and pore structure changes. Furthermore, pore volume and specific surface area increase with increasing maturity. In low-mature stage, the retained oil content begins to increase, pore volumes show slight changes, and primary pores are occluded by the generated crude oil of high molecular weight and density. In the oil-window stage, the retained oil content rapidly increases and reaches maximum, and pore volumes gradually increase with increasing thermal maturity. At high mature stage, the retained oil content begins to decrease, and the pore volume increases considerably owing to the expulsion of liquid hydrocarbon. In over mature stage, natural gas content significantly increases and kerogen transforms to asphalt. Numerous organic pores are formed and the pore size gradually increases, resulting from the connection of organic pores caused the increasing thermal stress. This study lays a foundation for understanding variation of hydrocarbon products during the thermal evolution of lacustrine shales and its relationship with the evolution of shale reservoirs.

Genetic Types, Distribution Patterns and Enrichment Mechanisms of Helium in China’s Petroliferous Basins

Helium is a strategic resource with many scientific, technical and industrial applications. However, despite its importance and scarcity, there is a lack of understanding on its origin, migration and accumulation processes. In view of this, the distribution patterns and enrichment mechanisms of helium are studied based on systematic analysis of the genetic types of helium in petroliferous basins in China. The helium in the petroliferous basins in China is mainly radiogenic, which involves the decay of U and Th. As expected, we found that, in one gas field, the helium content in natural gas increases with the age of reservoir rock, and in the same layer of the same structure within one reservoir, the helium content in natural gas in high altitude part of the structure is higher than that in the lower part. Enrichment of helium is closely related to old deep groundwater. The helium produced by radioactive decay in old strata is dissolved in water and transported and enriched through water migration. Due to large uplift of the structure during the Himalayan period, the helium dissolved in water was exsolved and accumulated with natural gas in the trap above the water. And thus, the helium-rich natural gas reservoirs formed. So, the helium contents in natural gas fields increase gradually along the flow direction of groundwater. The area with large range of uplift often shows higher helium content. This study not only provides a basis for the study of helium enrichment research, but also provides a new idea for industrial helium resource exploration.

Analysis of the static mixer effect on natural gas mixing process in a pipeline

Energy measurement is the most important measurement method in international natural gas trade, and the calorific value of gas is one of the core parameters of energy measurement. In practice, the calorific value of natural gas is usually calculated by analyzing the combustible components and percentage content of natural gas. Therefore, obtaining the natural gas sample with uniform quality is an important factor to accurately calculate the calorific value of natural gas. In this paper, the effects of four kinds of static mixers on the mixing process of natural gas in the pipeline will be studied from the perspective of improving the mixing uniformity of natural gas with different gas components in the pipeline. In addition, for each static mixer, the influences of its main geometric factors on the function of the mixer are discussed. The main conclusions are as follows:The spiral vane mixer have the best mixing effect on natural gas. One geometric factor affecting the working effect of the “S” tube mixer is the bending radius. The smaller the bending radius is, the better the mixing result of downstream gas is. Two geometric factors affecting the working effect of the reducer mixer are the inner diameter and total length of the reducer. When the inner diameter of the throat is the same, longer is the entire length of the reducer and worsens the mixing effect downstream. When the whole length of the reducer is the same, the larger the inner diameter of the throat, the worse the mixing effect. Two geometric factors affecting the working effect of the orifice plate mixer are the inner diameter and the number of orifices—the smaller the inner diameter and the fewer orifices, the better the mixing effect. Two geometric factors affecting the working effect of the spiral vane mixer are the axial length and rotation angle of the vane. When the axial length of the spiral vane is the same, the mixing effect increases with the increase of the vane rotation angle. On the other hand, when the vane rotation angle is the same, the mixing effect worsens with the increased axial length of the vane. The research results of this paper have a certain guiding significance for the accurate determination of the calorific value of the mixed natural gas in the gas station with multiple gas sources.

Supercritical CO2 utilization in a CO2 zero emission novel system for bio-synthetic natural gas, power and freshwater productions

Supercritical CO2 utilization is of interest because its supercritical conditions are easily accessible. Supercritical CO2 was utilized in this study in a Brayton cycle driven by a biomass gasification for power production and preheating a humidification-dehumidification desalination system. Biomass gasification triggered a methanation reactor for production of a bio-synthetic natural gas which is a synthetic natural gas obtained from a biomass resource. This technology has a promising performance because it approximately does not have carbon dioxide emission and producing bio-synthetic natural gas from a biomass gasification using a methanation reactor is a carbon dioxide negative technology. Response surface methodology has been utilized for comprehensive investigation and multi-objective optimization of the novel tri-generation system considering power production, freshwater flow rate, and methane content in bio-synthetic natural gas as criteria and selecting biomass feed rate, steam to biomass ratio and pressure ratio of supercritical carbon dioxide Brayton cycle as variable parameters. What stands out in results of analysis of variance is the dominance of biomass feed rate in shares on outputs. Biomass feed rate of 1.2 mol/s, steam to biomass ratio of 1.5 and pressure ratio of 3.5 resulted in the optimum response variables of power production of 172.6 kW, freshwater flow rate of 778.8 kg/hr, and methane content of 50.8% in bio-synthetic natural gas.

Microscopic Mechanism of Variations in Physical Parameters of Natural Gas Containing CO2 at Ultrahigh Temperature and High Pressure.

Owing to limitations imposed by the experimental requirements, it is difficult to carry out pressure–volume–temperature experiments on CO2-containing natural gas in high-temperature and ultrahigh-pressure gas reservoirs. Relevant research is also insufficient, which has led to a lack of clarity in current understanding of the microscopic mechanism of variations in the deviation factor of high-CO2 natural gas under high-temperature and ultrahigh-pressure conditions. This has greatly limited the development of natural gas reservoirs containing CO2. To reveal the microscopic mechanism of variations in the deviation factor of natural gas containing CO2 as a function of pressure under high-temperature and high-pressure conditions, by physical simulation experiments, the deviation factors of samples of sour natural gas with known CO2 contents from the Ledong gas reservoir were determined. Then, according to the idealized parameters of the physical experiment, a molecular model of natural gas containing CO2 was established using molecular simulation methods. Changes in molecular density, molecular volume, nonbonding interaction energy, potential energy, and kinetic energy during variations in the deviation factor of a CO2-containing natural gas system as a function of pressure under high-temperature and ultrahigh-pressure conditions were quantitatively studied. Using molecular simulation techniques, it was found that the changes in total energy, kinetic energy, and potential energy between molecules are the internal factors that cause variations in the deviation factor of natural gas systems containing CO2 under ultrahigh-temperature and high-pressure conditions. The results show that the increase of carbon dioxide content in natural gas will cause the total energy of natural gas molecules to decrease when the pressure is constant. This means that the higher the CO2 content in natural gas, the easier it will be compressed. This study should lay the foundation for investigating the mechanisms of the occurrence of CO2-containing natural gas, as well as facilitating the exploitation of CO2-containing natural gas.

Natural gas content of the “Five-meter” coal seam of the Neryungrinskoye field

The article examines, analyzes and consolidates the results of research (direct and indirect research methods) of the gas content of the “Five-meter” seam of the Neryungrinsky coal deposit, which is slated for underground mining. The article also presents the criteria that determine the representativeness of the tested samples by the direct method, which allow the introduction of indirect methods for studying the gas content of the “Pyatimetrovy” formation of the Neryungri field without losing the reliability of the results. As a result of the analysis of the factual material and the geological situation at the field, as well as taking into account the data on the current state of open pit mining at the field, the following were identified: the main factors influencing the degree and nature of the gas content of the Pyatimetrovy layer of the Neryungrinskoye field; composition of gases, the inflow of which is expected to enter the mine atmosphere during mining operations to extract coal from the “Five-meter” seam by the underground method. The main results of the research presented in the article are: the identification of two main gas zones of the “Five-meter” formation with the construction of a gas zoning diagram along the depth of the formation; determination of the presence of gas traps at the field with low production rate of free gas, which are determined by the presence of permafrost in the field; establishing the influence of open pit mining at the deposit on the activation of the natural degassing process of the coal seam and its host rocks at the present stage. The quantitative indicators of the methane content of the coal seam in the field have been established, it has been noted that natural gases in the host rocks are identical to those in the reservoir.

Experimental and simulation studies on the phase behaviour for gas hydrates in a CO2 rich gas dominant multiphase pipeline system

AbstractIn this work, an experimental and modelling study is performed to identify the phase behaviour of gas hydrates formation for a high CO2 content natural gas system and multiphase gas dominant system. Further, CSMGem, PVTSim, and Aspen HYSYS software packages are used to verify the prediction capabilities for gas hydrates formation conditions. Initially, thermodynamic equilibrium conditions are obtained using CSMGem, PVTSim, and Aspen HYSYS. Then, these results are validated and compared to the experimental work to verify the accuracy in predicting hydrate formation conditions. An experimental study is performed in the pressure range of 2–7 MPa for a pure system and multiphase system with the gas composition of carbon dioxide (70%) + methane (26%) + ethane (2%) + propane (1%) + butane (1%). The results show that the PVTSim software package shows the best accuracy with 99.9% for the pure system and 99.88% for the multiphase system.

Heat Transfer Characteristics of a Water Heater Operating on Natural Gas and Cofiring Pulverized Rumen Contents

Heat Transfer Characteristics of a Water Heater Operating on Natural Gas and Cofiring Pulverized Rumen Contents

Development Status of Drainage Gas Recovery Technology in High Sulfur Gas Wells

Due to the particularity of its stratigraphic structure, Sichuan Basin is rich in natural gas resources. With the production of gas wells, effusion is bound to occur in the wellbore. Once water invasion occurs, it will lead to the decline of natural gas production and even shutdown of the wells. Therefore, timely drainage of water in the wellbore is the key to restoring gas well production. Because of the high sulfur content of natural gas in Sichuan Basin, the conventional gas well drainage measures are difficult to apply, and some special drainage measures need to be taken. This paper mainly reviews the development and present situation of drainage technology for gas wells with high sulfur content, and introduces four main types of high sulfur gas well drainage gas recovery technologies: plunger gas lift, tubing perforation, electrical submersible pump drainage gas recovery technology, and foam drainage gas recovery, and compares their applicability, advantages and disadvantages.

Ultra-clean condensing gas furnace enabled with acidic gas reduction

Natural gas furnaces are the most common space heating equipment in the U.S. residential and commercial building markets. However, current residential natural gas condensing furnaces generate substantial acidic condensate as well as significant emissions of sulfur oxides (SOx), nitrogen oxides (NOx), carbon monoxide (CO), hydrocarbons (HC), and methane (CH4) contributing to environmental degradation of air, water, and soil. This paper describes a novel solution to reduce the environmental impact of natural gas condensing furnaces based on the technology of monolithic acidic gas reduction (AGR) catalyst for SOx trapping, NOx redox to nitrogen, and oxidation of formic acid, CO, HC, and CH4. This technology offers a new condensing natural gas furnace with both ultra-clean flue gas and neutral condensate. A prototype of the condensing gas furnace with the AGR component is demonstrated to have condensate with pH = 7, NOx emissions of 1–2 ng/J, and an annual fuel utilization efficiency (AFUE) of 96%. The AGR component and the AGR-enabled furnace were tested for long-term reliability and durability, as well as for SOx storage and regeneration activity. In addition, this paper provides new data on measurements of the specific acidic gas content in natural gas condensing furnaces.

Kinetic study of the effect of sub-atmospheric conditions on the laminar burning velocity of high C2H6 content natural gas mixtures

The laminar burning velocity (S L) was measured at sub-atmospheric pressure (0.84 atm) and an environmental temperature of 295 ± 2 K for two high C2H6 content fuel mixtures, 75% CH4 – 25% C2H6 (mixture M1), and 50% CH4 – 50% C2H6 (mixture M2), as well as the pure constituent fuels. The equivalence ratios for the experiments ranged between 0.8 and 1.4. Numerical calculations predicting S L were performed using 3 detailed reaction mechanisms, finding GRI-Mech 3.0 to achieve the best agreement at the pressure conditions evaluated. The pre-exponential factor of reaction H + O2 = O + OH (R38) was modified in order to improve the numerical results at sub-atmospheric conditions. Kinetic analysis by means of the defined reaction factor () was carried out to identify the mechanism for S L changes at sub-atmospheric conditions. According to the experimental results, S L increased by 15.9% and 26.3% for mixtures M1 and M2, respectively, at 0.84 atm as compared to 1.0 atm. The reaction pathways elaborated employing F R indicate that the increase in S L at sub-atmospheric conditions is caused by increased CH3 radical production by reaction C2H5 + H = 2CH3 (R159), which increases the formation of H radical through reactions O + CH3 = H + CH2O (R10) and O + CH3 = H + H2 + CO (R284). The recombination reactions associated with the production of CH4 and C2H6 also contribute to S L increases at sub-atmospheric conditions.

The Determination of the Methane Content of Coal Seams Based on Drill Cutting and Core Samples from Coal Mine Roadway

The determination of methane content of coal seams is conducted in hard coal mines in order to assess the state of methane hazard but also to evaluate gas resources in the deposit. In the world’s mining industry, natural gas content in coal determination is usually based on direct methods. It remains the basic method in Poland as well. An important element in the determination procedure is the gas loss that occurs while collecting a sample for testing in underground conditions. In the method developed by the authors, which is a Polish standard, based on taking a sample in the form of drill cuttings, this loss was established at a level of 12%. Among researchers dealing with the methane content of coal, there are doubts related to the procedures adopted for coal sampling and the time which passes from taking a sample to enclosing it in a sealed container. Therefore, the studies were designed to evaluate the degree of degassing of the sample taken in the form of drill cuttings according to the standard procedure and in the form of the drill core from a coal mine roadway. The results show that the determinations made for the core coincide with the determinations made for the drill cutting samples, with the loss of gas taken into account.