Natural Gas Methane Research Articles

Pressure broadening in Raman spectra of CH4–N2, CH4–CO2, and CH4–C2H6 gas mixtures

Different molecular environments change the spectrum of a given gas sample involved in a mixture compared to the spectrum of a pure gas. It is necessary to account for this effect to improve the accuracy of the analysis of the natural gas composition by Raman spectroscopy. First, the change in the main components of natural gas (methane, nitrogen, carbon dioxide, and ethane) must be considered. This work is devoted to the mutual influence of CH4–N2, CH4–CO2, and CH4–C2H6 on their characteristic Raman bands in the range of 300–2500 cm−1. The half-width and asymmetry of the Q branches of N2, CO2, and C2H6 as a function of methane concentration were obtained in the range of 1–50 bar. The averaged broadening coefficients of the rotational-vibrational lines of the ν2 band of CH4 perturbed by N2, CO2, and C2H6 are measured. A high-sensitivity spectrometer with a resolution of 0.5 cm−1 based on spontaneous Raman scattering was used to obtain reliable results. The algorithm and all the necessary parameters for simulating the effect of various molecular environments on the Raman bands of the main components of natural gas are presented.

On new requirements for the environmental indicators of agricultural tractors in the Customs Union

BACKGROUND: Decisions of the Council of the Eurasian Economic Commission No. 127 of October 29, 2021. and No. 89 dated 04/15/2022. amendments have been made to the Technical Regulations of the Customs Union On the safety of agricultural and forestry tractors and trailers for them (TR CU 031/2012).
 AIMS: Analysis of modern requirements for the environmental indicators of agricultural tractors in the Customs Union.
 METHOD: Analytical.
 RESULTS: By the decision of the Council of the Eurasian Economic Commission (October 29, 2021.) amendments have been made to the Technical Regulations of the Customs Union 031/2012, which cover the issues as follows: clarification of the requirements for the emission of harmful substances with exhaust gases from diesel engines, installed on mentioned tractors; introduction (for the first time) of requirements for emissions of harmful substances to dual-fuel engines (i.e. on the gas-diesel process); clarification of similar requirements for spark-ignition engines, operating on gaseous fuel. Environmental requirements for diesel engines correspond to the European level of Stage IIA level for the period up to 09/01/2022 and to the Stage IIIA after the specified period. The requirements for dual-fuel and gas engines are in accordance with those, specified in the technical documentation, until 09/01/2022 and in accordance with those, specified in TR CU 031/2012, after this date.
 CONCLUSIONS: Clarification in the Technical Regulations 031/2012 of the regulatory requirements for the emission level of agricultural tractors eliminates the ambiguity in understanding of these requirements.
 The replacement of conventional fuel with gaseous fuel theoretically provides a reduction in the emission of harmful substances from the exhaust gases of engines.
 The replacement of diesel fuel with natural gas (methane) allows, theoretically, to reduce the emission of carbon dioxide, considered as one of the gases, contributing to the greenhouse effect, by 15%.
 In order to ensure the development of the russian economy in the context of sanctions, it is advisa-ble to cancel the coming into force the Stage IIIA level environmental standards for agricultural tractors from 09/01/2022, which is given in the TR CU 031/2012.
 These changes concern relate, firstly, to the clarification of the requirements for the emission of harmful substances with exhaust gases from diesel engines installed on these tractors, and secondly, the introduction (for the first time) of the requirements for emissions of harmful substances to dual-fuel engines (i.e. on the gas-diesel process), and thirdly, clarification of similar requirements for spark ignition engines running on gas fuel. Fuel gas refers to compressed natural gas and liquefied petroleum gas. Environmental requirements for diesel engines for the period up to 09/01/2023. correspond to the European level of Stage II, and after the specified period to the level of Stage IIIA. For dual-fuel and gas engines. requirements for emissions of harmful substances: until 09/01/2023 - in accordance with those specified in the technical documentation, and after the specified period in accordance with those specified in TR CU 031/2012.

A linker conformation induced metal-organic framework with high stability and efficient upgrading of natural gas.

Natural gas plays an important role in daily life and the petrochemical industry, but there are often large amounts of impurities which prevent the full use of methane in natural gas. Developing excellent adsorbents to purify CH4 from multi-component mixtures is crucial, but also faces great challenges. Here, by utilizing a ligand conformation preorganization strategy, we employ a flexible nonplanar hexacarboxylate ligand with C2 symmetry to successfully construct a robust microporous metal-organic framework {[Cu3(bmipia)(H2O)3]·(DMF)(CH3CN)2}n (GNU-1, bmipia = 5-[N,N-bis(5-methylisophthalic acid)amion] isophthalate) with an unprecedented topology. More importantly, the obtained GNU-1 not only exhibits good stability in acid-base and water environments, but also shows potential utility as an adsorbent for efficient separation and purification of natural gas under ambient conditions. The adsorption isotherms of GNU-1a (activated GNU-1) exhibit strong binding affinities for C2H6 and C3H8, a remarkable uptakes of C3H8 (6.64 mmol g-1) and C2H6 (4.6 mmol g-1) and an excellent selectivity of 330.1 and 17.5 for C3H8/CH4 and C2H6/CH4 mixtures, respectively, at 298 K and 1 bar. The breakthrough experiments demonstrate that the ternary CH4/C2H6/C3H8 mixtures are completely separated using a fixed-bed separator packed with GNU-1a at ambient temperature and also show great potential for recovering the C2H6 and C3H8 contents from natural gas. Finally, Grand Canonical Monte Carlo simulations are adopted to ascertain potential gas adsorption mechanisms. This work proves the feasibility of optimizing the structure and pore size of MOF materials by regulating the conformation of ligands for application in the field of light hydrocarbon adsorption/separation.

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

Development and investigation of the technological process of plasma carbothermal reduction of slag from secondary metallurgy of aluminum

Based on a critical analysis of the current state and prospects of development of the problem of pyrometallurgical recovery/extraction of aluminum from aluminum-bearing industrial waste, the need to replace traditional, electrocarbonothermic processes and melting process units with innovative, plasma carbothermal processes and furnace-reactors, with the possibility of reverse feeding and recovery of gasified during melting metal and metal oxide components is substantiated. On the basis of this analysis a new technological scheme of smelting with a new design of plasma-arc furnace-reactor, which provides a solution to the problem using a special hollow double-shell graphite cathode connected to the system of circulating supply of gases separated from the reaction zone, was developed and presented. The proposed technological scheme also differs in the use of such highly active liquid and gaseous reagents as carbon-containing reducing agents as calcium carbide (CaC2) and methane (CH4). The main features of chemism of reducing processes are described. It is shown that by replacing traditional coke with anodized calcium carbide and natural gas (methane) the recovery rate of aluminum oxide (Al 29-34%) and silica (SiO2) and hematite (Fe2O3) present with it increases to 80-99%. Specific power consumption is reduced by 35-40%, the 90-95% reduction in the loss of target elements, the 80% reduction in the emission of greenhouse carbon dioxide, which is replaced by a very valuable recyclable synthesis gas - CO-H2. By additionally feeding separate portions of quartzite and steel-rolling scale in the furnace-reactor, a complex alloy-ligature of Fe-Si-Al-Ca system is melted, with the ratio of components: 1:[1.3-2]:[1.3-1.2]:[0.9-1.25]. With the introduction into industrial practice of the plasma carbothermal process of aluminum reduction from secondary aluminum dumping slags accumulated in the world (4 million tons/year), it will be possible to return up to 1-1.5 million tons/year of aluminum to the production processing cycle.

THE INFLUENCE OF HYDROGEN CONCENTRATION IN NATURAL GAS ON HEAT FLOWS IN A THERMAL AGGREGATE

Natural gas is currently a hotly debated topic both from an environmental point of view due to the production of CO2 and from an economic point of view. The article is focused on the analysis of selected energy factors when burning natural gas with a gradual increase in the hydrogen content in the fuel mixture. In the article, the authors focused on modelling combustion and the influence of hydrogen concentration on heat flows from flue gas in a thermal aggregate. The aim of the authors is to point out changes combustion in the thermal aggregate using document analysis and calculations. By gradually increasing hydrogen in natural gas, it is possible to prove the effect on heat flows during the exchange of heat from the flue gas to the heated material. According to the results, it can be concluded that increasing the content of methane in natural gas changes the nature of the combustion of the mixture. The combustion temperature increases, heat flow density, on the other hand, the volume of flue gas converted to 1 m3 of fuel decreases. An important factor that positively decreases in this is the CO2 emission factor.

Stability of submarine slopes during replacement of methane in natural gas hydrates with carbon dioxide

Replacement of methane (CH4) in natural gas hydrates (NGHs) with carbon dioxide (CO2) can sequestrate CO2 in the seabed while developing the natural gas, so it is an environmental-friendly energy production and carbon sequestration mode. A dynamic evolution model for the mechanical parameters of a NGH reservoir during CH4–CO2 replacement was established. Then, the finite element method was adopted to build a temperature-seepage-stress-saturation multi-field coupling model for CH4–CO2 replacement in the NGH reservoir to study the evolution of physical parameters of strata and the slope stability in the replacement process. Results demonstrate that mechanical parameters including the peak strength, elastic modulus, and cohesion of NGH and CO2 hydrate (CDH) bearing sediment samples are all positively correlated with the saturation. The generation of CDHs leads to a decrease in permeability of the reservoir during CH4–CO2 replacement, and the CO2 injection rate gradually slows down with the prolonging injection time of CO2. During CH4–CO2 replacement, the slope is more prone to failure with the increasing submarine slope angle, decomposition range of NGHs, reservoir thickness, and initial saturation; with the enlargement of the generation range of CDHs and the thickness of overlaying strata, the slope is more stable.

Combustion characterization of hybrid methane-hydrogen gas in domestic swirl stoves

Combustion of hybrid natural gas (methane) and hydrogen mixture in domestic swirl stoves has been characterized using hot-state experiments and numerical analysis. The detailed combustion mechanism of methane and hydrogen (GRI-Mech 3.0) has been simplified to obtain reduced number of chemical reactions involved (82 % reduction). The novel simplified combustion mechanism developed has been used to obtain combustion characteristics of hybrid methane-hydrogen mixture. The difference between the calculations from the detailed and the simplified mechanisms has been found to be <1 %. A numerical model, based on the simplified combustion model, is developed, rigorously tested and validated against hot-state tests. The results depict that the maximum difference in combustion zone’s average temperature is <13 %. The investigations have then been extended to hybrid methane-hydrogen mixtures with varying volume fraction of hydrogen. The results show that for a mixture containing 15 % hydrogen, the release of CO due to combustion reduces by 25 %, while the combustion zone’s average temperature reduces by 6.7 %. The numerical results and hot-state tests both confirm that the temperature remains stable when hybrid methane-hydrogen mixture is used in domestic swirl gas stoves, demonstrating its effectiveness in cooking processes.

ANALYSIS OF FORMATION THE GREENHOUSE EFFLUENTS TO ATMOSPHERE AND NITROGEN OXIDES PRODUCTION BY COMBUSTION THE METHANE-HYDROGEN MIXTURES

Within the framework of decarbonization of environment, the processes of the greenhouse gases formation in atmosphere by combustion the gas fuels (generally) and the natural gas substitution (particularly) the conditions of reducing the CO2 emission by methane-hydrogen mixtures burning are considered. The data on nitrogen oxides’ effluents are generalized in the work as well.&#x0D; An important role of non-isothermal state and of radiation selectivity of three-atomic gases CO2 and H2O for the resulting heat exchange and by evaluation the corresponding heat fluxes has been stated. The data are discussed basing upon the calculations’ results of the radiative heat transfer within the layer of combustion products (CP) of natural gas for the case of non-isothermal emitting layer at partial pressures pH2O : pCO2 = 2 : 1.&#x0D; The conclusion has been accepted on limitations regarding the opportunities to reduce the CO2 emission for the case of premixed methane-hydrogen mixtures burning while fuel combustion with an air-oxidant is proceeded. The evaluation under consideration has been proven taking into account only the cases of minor shares of [H2] ≤ 20–30 % (vol.) in fuel used by proper conditions for the domestic gas devices. The expected reduction of [CO2] mass emission fraction under combustion is reduced only by 10 % compared with the natural gas (methane) burning.&#x0D; It has been found for the first time that in case of the fuels, not containing the nitrogen, the equilibrium concentrations of two main nitrogen oxides NO and NO2 have practically the same (invariable) NOx values (by each of oxides), independently on fuel composition: methane and higher hydrocarbons, methane-hydrogen gas mixtures at any fixed given temperature (T = idem) and definite air-oxidant’s excess factor (λ = idem).&#x0D; This supposition has been numerically grounded and analyzed for the conditions of combustion the mentioned gas fuels under both the cases: of dry or wet air-oxidant. Bibl. 26, Fig. 4, Tab. 3.

Satellite quantification of oil and natural gas methane emissions in the US and Canada including contributions from individual basins

Abstract. We use satellite methane observations from the Tropospheric Monitoring Instrument (TROPOMI), for May 2018 to February 2020, to quantify methane emissions from individual oil and natural gas (O/G) basins in the US and Canada using a high-resolution (∼25 km) atmospheric inverse analysis. Our satellite-derived emission estimates show good consistency with in situ field measurements (R=0.96) in 14 O/G basins distributed across the US and Canada. Aggregating our results to the national scale, we obtain O/G-related methane emission estimates of 12.6±2.1 Tg a−1 for the US and 2.2±0.6 Tg a−1 for Canada, 80 % and 40 %, respectively, higher than the national inventories reported to the United Nations. About 70 % of the discrepancy in the US Environmental Protection Agency (EPA) inventory can be attributed to five O/G basins, the Permian, Haynesville, Anadarko, Eagle Ford, and Barnett basins, which in total account for 40 % of US emissions. We show more generally that our TROPOMI inversion framework can quantify methane emissions exceeding 0.2–0.5 Tg a−1 from individual O/G basins, thus providing an effective tool for monitoring methane emissions from large O/G basins globally.

Carbon isotopic composition of methane and its origin in natural gas from the Petišovci-Dolina oil and gas field (Pannonian Basin System, NE Slovenia) – a preliminary study

The carbon isotopic composition of methane (δ13CCH4) in natural gas from the Petišovci-Dolina oil and gas field (NE Slovenia) was measured for the first time in August and September 2021. The gas samples from different depths were taken from three wells: Dolina-deep (Pg-6) from the depth interval 3102–3104 m, Petišovci-deep (Pg-5) from the depth interval 2772–2795 m, and Petišovci-shallow (D-5) from the depth interval 1212–1250 m. According to the available composition dataset of gas, available from the Petrol Geo d.o.o. documentation, the “deep” gases sampled from the Pg-6 and Pg-5 wells consist of 85 % methane (C1), 11 % hydrocarbons heavier than methane (C2–C6) and 4 % CO2. The “shallow” gas from well D-5 contains more than 89 % methane, up to 11 % C2–C6 gases, while the CO2 content is negligible. The “deep« gas from the Pg-6 and Pg-5 wells has δ13CCH4 -36.7 ‰ and -36.6 ‰, respectively, while the “shallow” gas from the D-5 well has the δ13CCH4 of -38.6 ‰. The methane from the “shallow” gas is slightly enriched in the lighter 12C isotope. δ13CCH4 in the range from -38.6 to -36.6 ‰ clearly indicates the thermogenic origin of methane formed during the catagenesis phase of gas formation.

About the possibility of using natural gas as a fuel on agricultural tractors

AIMS: Evaluation of the effectiveness of converting diesel engines used in agricultural self-propelled vehicles to fully or partially natural gas (methane) fueled engines.&#x0D; METHOD: Is analytical.&#x0D; RESULTS: In agriculture up to 25% of operating expenses are fuel costs. However, the only number of the concomitant objective and subjective factors allow us to estimate expedience and efficiency of converting diesel engines used in agricultural self-propelled vehicles for full or partial supply of natural gas (methane). On the one hand, the price of an equivalent amount (in terms of work performance) of natural gas is more than 2 times lower than the price of diesel fuel. At the same time, natural gas is the most environmentally friendly hydrocar-bon fuel. But, on the other hand, the underdeveloped refueling infrastructure is obvious, and the environmental friendliness of natural gas itself is not a guarantee of the environmental friendliness of the engine itself. Also, the safety of gas equipment operation under high pressure is an important matter.&#x0D; CONCLUSIONS: Firstly, the use of natural gas instead of diesel fuel requires taking into account the difference in the physicochemical characteristics of these fuels, which determines both the requirements for the organization of the working process and the advantages and disadvantages of such replacement. Secondly, the combustion process of natural gas, compared to diesel fuel, is characterized by in-creased formation of water leading to more intensive watering of lubricating oil, although it re-duces carbon dioxide emission into the atmosphere. Safety of natural gas equipment operation plays an important role, and first of all, it is concern of cylinders that are filled at pressure of 20.025.0 MPa.

(Invited) Electrochemical Pumping for Hydrogen Storage and Distribution in the Natural Gas Pipeline

Over the next decade, the production and use of hydrogen in various sectors of the global economy is anticipated to grow significantly. It is an already important feedstock in the production of ammonia and desulfurization of fuels in addition to being used in metals refining and as a coolant in thermal electric power plants. More recently, hydrogen is being considered for long-term seasonal energy storage for energy derived from renewables like solar and wind. To alleviate the severe costs of building out completely new infrastructure, the U.S. natural gas pipeline represents an enticing proposition for hydrogen storage and a potential distribution network from centralized production facilities. Embrittlement concerns of the pipeline with hydrogen limit the hydrogen partial pressure/concentration of hydrogen to be stored. Because many end use applications often require high purity hydrogen, it is necessary to separate/de-blend hydrogen from natural gas and compress it at the point-of-use. This talk presents high-temperature polymer electrolyte membrane (HT-PEM) electrochemical hydrogen pumps for separating hydrogen from gas mixtures. Hydrogen purification to +99% from syngas (25mol% hydrogen and 40mol% carbon monoxide (CO)) at 1 A cm-2 and cell voltage of 0.4 V with an electrochemical hydrogen pump was demonstrated. About 90% of hydrogen used in the United States today derives from steam-reformed natural gas that contains large concentrations of CO – which is a potent platinum electrocatalyst poison at temperatures below 100 °C. The hydrogen purification from syngas was possible with an electrochemical hydrogen pump operated at 220 °C and by using: i.) an ion pair HT-PEM that exploits electrostatic interactions to prevent phosphoric acid leaching at elevated temperatures from the membrane matrix and in the presence of water and ii.) a phosphonic acid ionomer electrode binder. The membrane electrode assembly (MEA) with the said materials and platinum on carbon (Pt/C) electrocatalyst was also effective for purifying hydrogen from other types of reformed hydrocarbons with different CO and hydrogen concentrations. Unexpectedly, operating the HT-PEM hydrogen pump at 220 °C minimized CO impact on cell polarization. At this temperature, cell polarization was governed by the hydrogen concentration in the gas feed. These observations motivate future work to develop new electrodes and electrode binders that can extract, purify, and compress hydrogen with feed streams that have low hydrogen content and contain other constituents in natural gas (methane, ethane, t-butyl mercaptan, etc).

The expansion of natural gas infrastructure puts energy transitions at risk

Whether additional natural gas infrastructure is needed or would be detrimental to achieving climate protection goals is currently highly controversial. Here we combine five perspectives to argue why expansion of the natural gas infrastructure hinders a renewable energy future and is no bridge technology. We highlight that natural gas is a fossil fuel with a significantly underestimated climate impact that hinders decarbonization through carbon lock-in and stranded assets. We propose five ways to avoid common shortcomings for countries that are developing strategies for greenhouse gas reduction: manage methane emissions of the entire natural gas value chain, revise assumptions of scenario analyses with new research insights on greenhouse gas emissions related to natural gas, replace the ‘bridge’ narrative with unambiguous decarbonization criteria, avoid additional natural gas lock-ins and methane leakage, and take climate-related risks in energy infrastructure planning seriously. Often presented as a bridge technology to a future zero-carbon energy system, natural gas infrastructure expansion remains hotly debated. Here Kemfert et al. discuss recent research to argue how such expansion hinders climate targets and energy transitions and suggest how research can support better planning.

Comparative analysis of the concentration of CO2, CO, CH, and O2 in the exhaust gases of BelAZ dump trucks that use liquefied natural gas as a motor fuel

The paper aims to compare the CO2, CO, CH, and O2 concentrations in the exhaust gases of Cummins KTA 50 diesel engines of BelAZ 75131 mining dump trucks equipped with an onboard cryogenic fuel system and running on diesel and gas-diesel fuel at coal mines of Kuzbass (Russia). The research novelty lies in determining ecological efficiency when using liquefied natural gas (methane) as a motor fuel for heavy-duty mining dump trucks. In the near future, the use of this type of motor fuel will minimize the anthropogenic impact on the environment by reducing harmful emissions and provoking the environmental safety of the region where a large amount of mining equipment is used in coal mining enterprises. The demand for mining dump trucks, their operating conditions, and the world experience in converting mining equipment to liquefied natural gas (methane) were briefly analyzed. The use of alternative fuel sources for heavy-duty mining trucks is a promising way to reduce harmful emissions into the atmosphere. This paper presents a research technique. The data on the study of the CO2, CO, and CH groups and O2 concentrations in the exhaust gases of Cummins KTA 50 diesel engines of BelAZ 75131 mining dump trucks hauling rock mass are presented. The obtained data on the CO2, CO, and CH groups and O2 concentrations during diesel and gas-diesel operation of empty and laden BelAZ 75131 mining dump trucks when going uphill and downhill were substantiated. The results of calculating the average weighted emissions of the CO2, CO, and CH groups in the exhaust gases of Cummins KTA 50 diesel engines were presented.

Energy, economic and environmental assessment of photocatalytic methane production: a comparative case study between Japan and Malaysia

Photocatalytic methane (CH4) production wherein CO2 is reduced to CH4 by utilizing solar radiation energy is gaining research and industrial focus because of its environmental-friendly notion. It offers twofold advantages: reduction in CO2 emission and production of artificial natural gas (methane) at the same time. In this paper, comparative energy, economic and environmental assessment of such photocatalytic methane production has been carried out between Japan and Malaysian conditions. Assumptions on the photocatalytic methane production plant and estimation of energy production, CO2 emission reduction, and economic indicators are made based on previous research and existing technologies. Energy analysis shows that Malaysia has a higher potential for energy production and CO2 emission reduction than Japan. Economic analysis reveals that the feasible reaction efficiencies of the plant in Japan and Malaysia are 8%. The slightly higher conversion efficiency in Malaysia is due to the energy price and CO2 tax. For the implementation of the photocatalytic methane production plant, the high energy price and CO2 tax will work as a driving force.

Микропористый углеродный материал с высокой объемной емкостью аккумулирования метана

A compacted microporous carbon material (CMC-032) was obtained, which has a number of unique properties: a high specific surface area according to BET (SBET = 2384 m2/g), a large volume of micropores (~ 0.95 cm3/g), and a very high ability to retain methane 336 m3/v3. Sorbent CMC-032 is obtained by activating polymer raw materials with potassium hydroxide and compaction by hot pressing using polyvinyl alcohol as a binder. In the most demanded range of methane accumulation pressures of 3,5 – 10,0 MPa, the amount of accumulated methane in the system with CMC-032 reaches 270 m3/m3. The amount of methane stored in the system with and without CMC-032 adsorbent at 100 bar differs by about 3 times. The physicochemical properties of the obtained CMC-032 adsorbent were studied using methods including adsorption-desorption of N2 at 77 K, X-ray diffraction analysis, FTIR spectroscopy, Raman spectroscopy, and transmission electron microscopy. Based on the adsorption characteristics, it was found that CMC-032 is a promising material for storing natural gas methane. It is assumed that the high adsorption capacity is due to the high micropore volume and packing density.

Використання модельного газу в дослідженнях газового двигуна електростанції

Annotation – The analysis of scientific publications over the past ten years in the direction of creating gas ICEs in Ukraine, operating on natural gas, biogas or similar low-calorie fuels. The objectives of the work summarize the results of studies on the use of model gas in a gas internal combustion engine operating on a power plant drive. Developed recommendations on biogas additives to natural gas depending on the power plant load, and to develop a fuel control algorithm. The article provides recommendations on setting up the power system and automatic regulation of a gas engine running on a mixture of natural gas (methane) and biogas. To solve the tasks, a gas-electric installation with a rated power of 30 kW was tested. Initially, the installation was equipped with an 8-cylinder gasoline engine with spark ignition and an electric generator. The base ICE was converted to purely gas with a compression ratio of 8.5. In the physical modeling of biogas to natural gas additives in the model gas, the volume fraction of carbon dioxide increased to 30 % with a decrease in the load. By calculation, determined a similar ratio of compressed natural gas and biogas additives. For the calculation, it assumed that natural gas contains 90 ... 95 % methane, and biogas 60 % methane and 40 % carbon dioxide. The possibility of using biogas with 60 % methane as an additive to natural gas in piston ICEs with spark ignition has been confirmed. It was found that with a decrease in load, the biogas fraction increase and replace up to 85 % of natural gas. When working on biogas additives, the values of the concentrations of hydrocarbons and residual oxygen in the exhaust gases were determined to control the setting of the gas equipment of the internal combustion engine. Under operating conditions, three test modes selected for the power plant: idle, 50 % load, rated mode. The research results can serve as the basis for creating a control algorithm for the supply of biogas additives to natural gas, depending on load changes.

Natural gas methane number and its influence on the gas engine working process efficiency

The natural gas usage as a vehicle fuel in the mining industry is one of the priority tasks of the state. The article pays special attention to the component composition of natural gas from the point of view of its thermal efficiency during combustion in the combustion chamber of a power plant on a heavy-duty vehicle in difficult quarry conditions. For this, domestic and foreign methods for determining the main indicator characterizing the knock resistance of fuel in the combustion process – the methane number – are considered. Improvement of technical and economic indicators will be carried out by changing the composition of the gas mixture based on methane to fit the design features of the gas power plant, the methane number will be the determining indicator. A theoretical analysis of the influence of the methane number on such engine parameters as the compression ratio and the maximum speed of the flame front propagation in the second phase of combustion in the engine cylinder, expressed through the angle of rotation of the crankshaft, is presented. Based on the results of theoretical and experimental studies, the dependences of the influence of the methane number on the efficiency of the working process of the engine and its external speed characteristic were obtained.

Membranes open up new sources of helium

Back in the day, when you drilled a well and gas came out, you’d set a match to it. If the plume caught fire, you started natural gas recovery. If not, you sealed it back up and moved on. But even when a gas reservoir doesn’t have enough hydrocarbons for drillers to make a profitable energy play, sometimes there’s helium in them there hills. Liter for liter, helium is worth at least 40 times as much as natural gas. Most helium on the market today comes from wells that were drilled primarily for natural gas—methane in particular. The US Geological Survey recently estimated that the US has 8.7 billion m 3 of helium that could be recovered profitably as a side product of natural gas extraction. Despite that rosy number, the reality is that the global helium market has dealt with three major shortages since 2006 as well as many