Gas Formation Processes Research Articles

PERIODIC FOAMING DURING SELECTIVE ISOLATION OF HIGHLY PERMEABLE CHANNELS OF POROUS MEDIUM

Selective isolation of watered interlayers by forming barriers formed by highly viscous gels or insoluble precipitates does not always lead to the desired results. Field experience confirms that at some distance from the formed barrier, the filtration flow restores its configuration and the water injected into the formation again moves through highly permeable channels. An increase in the efficiency of flow deflection can be achieved by creating not a single barrier, but a whole sequence of alternating deep-penetrating insulating barriers, separated from each other by a certain distance in highly permeable pores. The paper presents the results of studies of quasi-periodic foaming in order to control mobility under conditions of selective isolation of water in pore channels of high permeability. Foaming occurs due to the in-bulk reaction between concentrated aqueous solutions of gas-generating and gas-generating solutions. Flow pattern of injected aqueous solutions of foaming reagents along current tubes is investigated. The task is to determine the space-time distribution of reagents in given zones of the porous medium. The problem of establishing the correlation between the spatial distribution of the gas formation zone and the dynamics of the gas formation process over time on the one hand, as well as the concentration of reactants, the diffusion rate (mutual diffusion), the gas generation rate and the probability of nucleation on the other hand was solved. The degree of flow blockage in highly permeable zones of the formation depends on the rate of in-situ foam generation and the simulation consists in the fact that it is similar to the law of filtration with a limiting gradient. The paper discusses the process of quasi-periodic gas formation during the movement of mixing solutions in porous media. In stationary filtration in a homogeneous porous medium, the process is described by the proposed system of equations. A system of equations is proposed that describes the movement of a liquid taking into account adsorption of reagents, diffusion and dynamics of the foaming reaction. The results obtained can serve as the basis for developing a method for controlling the water cut of porous media during waterflooding of oil formations. This, in turn, leads to the leveling of the displacement front and an increase in the completeness of coverage.

Analysis of the sintering process of the sintering charge in a high layer. Report 2. Reduction and oxidation processes, moisture behavior and gas dynamics of the sintering process

Piece of information 1 of this article briefly examines the history of the development of modeling the sintering process. To study it, a modern three-dimensional mathematical model was used. Its adaptation was made for the operating conditions of sinter plant No. 5 of PJSC “MMK”, on whose sinter machines the mix is sintered in a bed 700 mm high. Studies have been carried out on the formation and development of fuel combustion and limestone dissociation zones. In the information under consideration, the reduction and oxidation processes of moving the temperature fields of the material with the melt, the combustion zone, processes of gas formation along the height of the bed are presented together. It has been established that a small-height Fe2O3 reduction zone is formed under the fuel combustion zone, and that the conditions for the formation of an oxidation zone under the fuel combustion zone, discussed in the literature, are extremely unfavorable. An analysis of the processes of drying and waterlogging of the mix in a high bed was carried out. A lesser negative impact of moisture condensation in a high bed has been established compared to a low or medium height bed. The gas-dynamic operation of the bed under the ignition hearth with throttling conditions of the first vacuum chambers of the sinter machine is considered. A decrease in the rate of gas filtration at the outlet of the bed was established in comparison with the input rate after the drying and fuel combustion zones exited the bed.

РЕЗУЛЬТАТЫ ЭКСПЕРИМЕНТАЛЬНЫХ ИССЛЕДОВАНИЙ БИОРЕАКТОРА ДЛЯ ОБРАБОТКИ ПОБОЧНЫХ ПРОДУКТОВ ЖИВОТНОВОДСТВА

Reusing livestock by-products can increase the profitability of an agricultural enterprise and improve the environmental situation around it. One of the ways to process organic waste is anaerobic digestion to produce biogas. An analysis of common designs of biogas plant mixing systems showed that their common disadvantages are: increased risk of depressurization due to the presence of moving parts in the bioreactor and their seals; significant time costs to comply with the technology; with a sectional bioreactor, several pumps are used. An automated hydraulic mixing system has been developed for an experimental sample of a biogas plant, including: a recirculation pump, suction and discharge pipelines, time relays, solenoid valves for water supply, pressure gauges, valves. The influence of technological parameters of the hydraulic mixing system on the intensity of the gas formation process was studied. A regression equation was obtained to determine the influence of the duration and frequency of mixing on the efficiency of the process of processing livestock by-products. It has been established that in the selected interval the process of gas formation, according to the results of this multifactorial experiment, is directly proportional to the frequency of mixing of the processed substrate. Periodic stirring of the fermented mass for 10 minutes every 4 hours is proposed to maintain stable and efficient operation of the biogas plant. These technological parameters make it possible to more effectively prevent the formation of floating crust and sediment, areas of different temperatures and pH inside the digester, and also contribute to the uniform distribution of the bacterial population in the volume of the bioreactor.

Effects of Pretreatment with a Ball Mill on Methane Yield of Horse Manure

Lignocellulosic biomass is an abundant organic material, which can be utilised in biogas plants for sustainable production of biogas. Since these substrates usually have high lignin contents and consist of rather elongated particles, a special pretreatment is required for an economical and process-stable utilisation in the biogas plant. The mechanical pretreatment of horse manure was carried out with the prototype of a ball mill at different speeds. The aim of ball milling is to comminute the substrate and disintegrate the lignocellulosic bond. Mechanical pretreatment in the ball mill resulted in a significant increase in specific methane yield of more than 37% in anaerobic batch digestion (up to 243 LCH4 kgVS−1) of horse manure. The kinetics of the methane gas formation process was analysed by a modified Gompertz model fitting and showed a higher methane production potential and maximum daily methane production rate as well as a lower duration of the lag phase after pretreatment at 6 rpm. This was further confirmed by sieve analyses, which showed a significant reduction of particle size compared to the untreated variant. Thus, the use of the ball mill increases the specific methane yield and improves the fermentation of lignocellulosic substrates such as horse manure.Graphical

Peculiarities of CH4 and CO2 Distribution in Sediments of the Arctic Seas

The distribution of the concentrations of CH4 and CO2 and other gases in the sediments of the Kara, Laptev and East Siberian seas was studied. A correlation was found between CH4 and CO2 in most sediment cores. The correlation coefficient R for the sediments of the Kara Sea ranges from 0.58 to 0.97 and does not depend on the gas distribution with depth. Methanogenesis in marine sediments is presumably associated with sulfate reduction, and hydrogenotrophic methanogenesis leads to an increase in CH4 concentration against the background of high CO2 concentration. The high concentration of dimethyl sulfide in the sediments indicates the simultaneous formation of CH4 and CO2 through methylotrophic methanogenesis with the participation of CH3SCH3. In the upper layers of the sediment, opposite trends in the CH4 and CO2 distribution can be observed. The fact that the correlation coefficients between CH4 and CO2 gases in the sediments of the Laptev Sea acquire both negative and positive values is probably related to the fact that gas formation processes in the upper layers of the sediment captured by short columns differ from those of deep layers.

Effect of Hot Metal Gas Forming Process on Formability and Microstructure of 6063 Aluminum Alloy Double Wave Tube.

The hot metal gas forming process can significantly improve the formability of a tube and is suitable for the manufacturing of parts with complex shapes. In this paper, a double wave tube component is studied. The effects of different temperatures (400 °C, 425 °C, 450 °C and 475 °C) and different pressures (1 MPa, 1.5 MPa, 2 MPa, 2.5 MPa and 3 MPa) on the formability of 6063 aluminum alloy tubes were studied. The influence of hot metal gas forming process parameters on the microstructure was analyzed. The optimal hot metal gas forming process parameters of 6063 aluminum alloy tubes were explored. The results show that the expansion rate increases with the increase in pressure. The pressure affects the deformation of the tube, which in turn has an effect on the dynamic softening of the material. The expansion rate of parts also increases with the increase in forming temperature. The increased deformation temperature is beneficial to the dynamic recrystallization of 6063, resulting in softening of the material and enhanced deformation uniformity between grains, so that the formability of the material is improved. The optimum hot metal gas forming process parameters of 6063 aluminum alloy tubes are the temperature of 475 °C and the pressure of 2.5 MPa; the maximum expansion ratio is 41.6%.

Indicators of bread sticks based on wheat, rye flour and powders of large-fruited and smallfruited varieties of tomatoes

The article presents the results of determining the quality indicators of composite mixtures, semi-finished products and bread sticks based on wheat flour of the first grade, sifted rye flour in ratios of 70 and 30 parts; 80 and 20 parts and powderes of large-fruited and small-fruited varieties of tomatoes at a dosage of 1–9 % by weight of the flour mixture. An increase in the titratable acidity of composite mixtures, dough and baked products was noted with an increase in the amount of tomato powders while the wettability of products remained virtually unchanged. A suspension of powderes of large-fruited and small-fruited tomatoes activated the processes of gas formation, which made it possible to improve the dough process. No significant differences were found between the quality indicators of samples of mixtures and bread sticks when using powder from large-fruited or small-fruited tomatoes, as well as at different ratios of wheat and rye flour, but with the same dosages of enrichment. It is proposed to use the powder of large-fruited varieties of tomatoes in the amount of 7% for the activation of yeast in the production of functional bread sticks.

Study on Pyrolysis Hydrocarbon Generation Kinetics and Shale Gas Formation Process of Marine Continental Transitional Rocks in Shanxi Formation, Ordos Basin

The marine continental transitional facies shale of Shan23 sub member of Shanxi Formation in Ordos Basin was selected, and the hydrocarbon generation kinetics of Shan 23 sub member marine continental transitional facies shale was studied through open system thermal simulation experiment. The experimental results show that the pre exponential factor of Shan 23 shale is 12.92*1015/s, and the activation energy is mainly concentrated in 52~82kcal/mole. On this basis, combined with petromod basin simulation software, the burial history, thermal evolution history and hydrocarbon generation history of Shanxi Formation shale are established, and the formation process of shale gas is clarified. Finally, using the genetic method, combined with the original TOC restored by Petromod basin simulation software and the hydrocarbon generation obtained from the open system thermal simulation experiment, the resources of the study area are calculated when the hydrocarbon expulsion efficiency is 50%. The calculation results show that the shale gas resource in the study area is 12.41*1012m3, which shows a good exploration potential of sea land transitional facies shale in the study area.

Bulk and intramolecular carbon isotopic compositions of hydrocarbon gases from laboratory pyrolysis of oil shale of the Green River Formation: Implications for isotope structures of kerogens

Evaluation of intramolecular isotope distributions within organic compounds can provide important insights into gas formation processes and structural properties of gas-generating precursors, such as kerogen, bitumen, and oil, in natural reservoirs. Until recently, little has been known about the intramolecular isotope distributions within kerogens. In this study, we conducted systematic pyrolysis experiments of gas generation from a lacustrine oil shale of the Eocene Green River Formation under hydrous and anhydrous conditions (equivalent maturity or Easy %Ro: 0.76 to 3.27 at 310 to 480 °C for 3 to 50 days), measuring gas yields and compositions, as well as bulk and position-specific (PS) carbon isotope compositions. Gas generation processes were investigated in combination with kinetic Monte Carlo (kMC) simulations on a model Type I kerogen based on the chemical structures of oil shale of the Green River Formation. The comparison of our experimental results with kMC modelling indicates a series of β-scission, radical isomerization, and recombination reactions better represent the bulk isotope compositions of propane in the pyrolysis of the oil shale of the Green River Formation, but the ΔCc-t (= δ13Ccen – δ13Cter) values of propane at Easy %Ro > 1.5 can be better simulated by a simple combination of propyl groups with H radicals. Combining our previous works on marine shale of the Woodford Formation and Springfield Coal Member of the Carbondale Formation, PS carbon isotopes of propane indicate that in the lacustrine shales of the Green River Formation and the marine Woodford Shale, propane is sourced from CC bond cleavage, while CO bond cracking generates propane from coal at the initial kerogen cracking stage. At high maturity, the differences of late-stage propane production among the source rocks lead to the different bulk and PS C kinetic isotope effects of propane. Our findings suggest that the δ13C at the terminal position of propane precursors is likely up to 3.6‰ higher than at the central position in the Green River kerogen, while they are similar in the marine shale of Woodford Formation. In addition, the δ13C at the central position of propyl groups attached to heteroatom compounds is relatively more positive in the Springfield Coal Member of the Carbondale Formation than in Green River kerogen. A comparison of intramolecular C isotopes of propyl groups in the kerogens with their bulk δ13C, based on the PS δ13C of early-generated propane, contributes to our understanding of heterogeneities of isotopic structures of sedimentary organic matter.

Glass-Crystalline Materials of a Cellular Structure, Formed by Vibration Foaming Technology

A method for producing cellular materials on a glass-crystalline matrix has been developed. The formation of a porous structure is ensured by the process of gas formation, combined with a vibration effect on the raw mass. The possibility of gaining the plastic strength of the raw mass, sufficient for fixing the cellular structure of the raw material without adding binders, has been established. The main component of the raw material mixture is a finely ground filler, obtained after grinding glass-crystalline frit of a specially selected composition. For its formation pre-compacted raw masses, containing natural silica and glass-forming additives, are heated. There was investigated the joint influence of the compositions formulation and the roasting parameters on the properties indicators of the glass composite.

THE EFFECT OF MULTIAXIAL DEFORMATION ON THE DYNAMICS OF BIODEGRADATION AND CELL COLONIZATION OF ALLOY WE43

Introduction. The development of materials for bioresorbable implants is an urgent issue in medicine and materials science. Magnesium alloys are promising materials for this purpose. In particular, alloy WE43 (Mg-Y-Nd-Zr) has proven itself well in this field. However, the use of magnesium alloys is limited by a high degradation rate, which is often accompanied with nonuniform corrosion, which negatively affects the load bearing capacity of the product. In addition, the increased degradation rate usually seriously worsens the biocompatibility of magnesium alloys. Therefore, the study of the corrosion resistance of magnesium alloys, as well astheir biocompatibility, is an urgent task.Purpose of the study was to investigate the effect of multiaxial deformation (MAD), aimed at increasing the mechanical characteristics of the alloy WE43, on its biodegradation kinetics, as well as on cell colonization.Materials and methods. The alloy WE43 in two states – homogenized (WE43 hom) and strengthened by MAD (WE43 MAD) was investigated in this work. The kinetics of biodegradation was investigated on an xCELLigence RTCA Systems analyzer. A method for estimating the volume of hydrogen was used to study the process of gas formation, which was recorded using an automated digital microscope LionheartTM FX. The corrosive medium was a solution based on Dulbecco’s Modified Eagle’s Medium. A culture of mesenchymal multipotent stromal cells was used to study the colonization of the alloy surface by cells.Results. MAD of the alloy WE43 leads to a decrease in the biodegradation rate and the intensity of gas formation. The period of stabilization of biodegradation for the alloy after the MAD is 16 hours versus 3 hours for the alloy after homogenization. In this case, the volume of released hydrogen was 65.0 ± 4.4 mm3H2/mm3 alloy and 211.0 ± ± 21.1 mm3H2/mm3 alloy for the alloy after MAD and homogenization, respectively. MAD improves the biocompatibility of the alloy WE43, stimulating the colonization of mesenchymal multipotent stromal cells.Conclusion. MAD reduces biodegradation and improves the biocompatibility of the alloy WE43, which makes it a promising medical material, including for the purposes of oncoorthopedics

Investigation of Gas Formation Processes in Cotton Fabrics Impregnated with Binary Compositions of Ethyl Silicate - Flame Retardant System

The use of complex fire-retardant coatings based on ethyl silicate gel - diammonium hydrogen phosphate reduces the process of smoke formation during thermal exposure to treated tissue samples, which is promising for improving the fire safety of textile materials. The compositions are easy to obtain, they do not require specific processing conditions, do not contain toxic substances. This allows us to offer developed compositions for fire protection of textile materials used in facilities with a large number of people.

(IMCS Second Place Best Poster Award) In-Situ Analysis of Volatile Organic Compounds in Biogas Fermentation Processes Using a Metal Oxide Gas Sensor Array

(IMCS Second Place Best Poster Award) In-Situ Analysis of Volatile Organic Compounds in Biogas Fermentation Processes Using a Metal Oxide Gas Sensor Array

Heat-resistant structural composite material based on modified titanium hydride

The paper presents the results of studies of technological parameters of production, physical, mechanical, thermophysical properties and processes of gas formation during thermal heating of a composite material based on a modified fraction of titanium hydride and a Portland cement binder. The introduction of a plasticizing additive into the composite makes it possible to improve the technological and strength characteristics of the protection material. It has been shown that the decrease in the physical and mechanical characteristics of the material does not exceed 10 - 20%, which indicates its thermal stability in terms of the main performance indicators. The introduction of a boron additive does not significantly affect the physical and mechanical properties of the composite. It was found that the main gas evolution occurs during the drying of composites and practically ends after its completion. Reheating the cooled block to the initial heating temperature (300-350 °C) practically does not cause gas or water evolution, if during the cooling period the material had no contact with water.

In-Situ Analysis of Volatile Organic Compounds in Biogas Fermentation Processes Using a Metal Oxide Gas Sensor Array

1. Introduction and Motivation Considering the global climate change, the efficient use of clean and renewable sources of energy is one of the key research areas. In this context, the biological production of methane and other combustible biogas produced by anaerobic fermentation of organic wastes is gaining growing importance. These fermentation processes attract more and more interest mainly due to the possibility to use different types of residues like food waste, dairy wastes and many other organic wastes as feeding substrates. However, efficient biomass conversion to biogas is only possible if the process parameters taking direct influence on the fermentation process are continuously and reliably monitored. This allows efficient process control. One of such key process parameters are the volatile fatty acids (acetic, propionic, butanoic) formed during the biomass conversion process. The reliable monitoring of such organic acids and other volatile organic compounds (VOCs) gives valuable information and their analysis even at low concentrations (<2000 ppm) allows to model the actual microbial state and to adapt the feeding to keep their concentration and their inhibiting influence on the fermentation process low.Conventionally, the analysis of the organic acid composition in anaerobic fermentation processes is done by sophisticated methods like gas chromatography [1], infrared spectroscopy [2], and high pressure liquid chromatography (HPLC) [3]. However, the major disadvantages of these methods are their complicated and time consuming sample pre-treatment routines and high costs.In this paper, an automated measuring system developed by combining a silicon rubber membrane based carrier gas probe (Fig. 1) with a thermo-cyclically operated metal oxide gas sensor array [4] is introduced. This automated system might enable in-situ monitoring of different VOCs developing during the bio-fermentation processes in time periods of about one hour.1. Method of VOC monitoring Metal oxide gas sensors (MOGs) are well established as gas sensing devices for monitoring of VOCs and oxidizable gases like CO, H2 and CH4. Thus, before measurement of dissolved VOCs, CH4 and other to cross-sensitivity contributing gas components present in the biogas fermentation sample must be driven out. In a first step, a small amount of the fermentation liquid (about one liter) is extracted from the main reactor and its pH is shifted to an alkaline value by dosage of potassium hydroxide. This allows transformation of the dissolved organic acids to the dissociated state and enables purging out CH4, H2 and all other non-acidic, physically dissolved gas components contributing to the sensor signal, by a high flow of N2. Then, pH is shifted to a value near or even lower than the pKa value of the organic acids by dosage of phosphorous acid. Now the dissolved organic acids are in the undissociated molecular state and equilibrate with the gas state (Henry´s law). This enables the uptake of molecular dissolved organic acids from the liquid state into the constant flow of synthetic air (carrier gas: 5ml/min) by permeation through the gas permeable silicon rubber membrane of the gas carrier probe. By the help of the carrier gas the organic acids are transported to the metal oxide gas sensor array (Fig 1a) for analysis.1. Results and Discussion Several SnO2/additive gas sensing composites have been prepared and the most interesting candidates with respect to their remarkably high sensitivity and most characteristic conductance vs. time profile (CTP) shapes when operated in thermocyclic mode [4,5] will be reported. When the carrier gas probe is immersed in acetic acid/deionized water admixtures some metal oxides show characteristic CTP-shapes (Fig. 1b) representing the individual surface reaction processes with acetic acid. In addition, some first experiments with real fermentation liquids resulted in some unexpected gas developments with pH and time well indicated by characteristic CTP-changes, which will highlight the presentation.1. Conclusions and outlook By some extended in-situ monitoring experiments of acetic acid in deionized water as a model substance using a gas carrier probe combined with a 4-fold metal oxide sensor array, several metal oxide materials could be identified as good candidates for monitoring of organic acids in biogas fermentation processes.Monitoring experiments in real fermentation samples and analysis of the CTPs yielded gas formation changing with pH and time. These gas formation processes have to be referenced by simultaneous Gas Chromatograph-Mass Spectrometry (GC-MS) analysis and the results will be reported as well in context with the MOG sensitivity data.1. Acknowledgement This work is part of the EBIPREP collaboration project (www.ebiprep.eu/). It is financed by the EU International Programme INTERREG V Oberrhein 2017-2020.

PENGARUH KECEPATAN ALIRAN UDARA DENGAN PENGATURAN DIMMER PADA TEKANAN UDARA MASUK PADA PROSES GASIFIKASI SEKAM PADI TERHADAP PEMBENTUKAN FLAMABLE GAS

The biomass gasification process is a way to obtain combustible syn-gas through combustion of biomass in a closed reactor with the help of air from a compressed blower. Without the help of air gas formation process is not possible, the combustion in the furnace must have air that can start a fire. The tool for supplying air is a pressure blower. The purpose of this study was to obtain a stoichiometric air and biomass mixture in the rice husk gasification process. With the stoichiometric air fuel ratio (AFR) in the rice husk gasification process, it will produce a perfect flammable syn-gas.The method used in this research is to change the rice husk solid through the gasification process. The gas released in the gasification process will be varied at the blower speed with or without using a dimmer. From the test results, it can be seen in the syn-gas output from the reactor. on dimmer 1 the inlet airspeed is 3.5 m / s, on dimmer 2 the airspeed is 4.0 m / s. In dimmer 3 the air velocity is 4.5 m / s and in dimmer 4 the air velocity produced is 5.0 m / s From the results of testing the air velocity of each variation that enters the reactor only air velocity 4.5 m / s and 5.0 m / s or in dimmers 3 and 4 which can produce flammable syn-gas.

Механизм формирования карбидокремниевого покрытия диффузионным методом в кремниевой засыпке на углерод-углеродных композиционных материалах

The pack cementation process, used for obtaining coatings, is described, as a rule, in terms of solid-phase diffusion, which leads to saturation of the near-surface layer of the workpiece with a certain element. This method allows the deposition of a silicon carbide coating on carbon-carbon composite materials, that increases its resistance to the action of high-temperature oxidizing environments. An analysis of the kinetic features of the formation of silicon carbide on a carbon material indicated the difference between this method and the classical diffusion saturation. It turned out that it is necessary to consider additional processes of gas formation that occurs in the powder filling. A mechanism has been proposed, according to which it is possible to transfer silicon through the gaseous reagent SiO, generated in the backfill with the help of oxide additives, like aluminum oxide, which were previously considered inert.

Mineral Oil versus Vegetable Oil as Electroinsulating Fluids in Contact with Coating LacquersA thermochemical stability study

The thermochemical stability of a MOL (mineral oil) electroinsulating mineral oil was studied by the gas chromatography technique, compared with a Voil (vegetable oil) electroinsulating fluid based on natural esters (oil), exposed to a longer (1000 hours) thermal treatment (110 � 5 �C) in contact with the core transformer plate (silicon steel sheet) both blank and covered by immersion with three different types of lacquers (L-G epoxide, L-528 alkyl epoxy-melamine copolymer and L-S polyurethane). Experimentally it was noted that during the thermal treatment applied and in contact with the silicon steel sheet, the investigated oils have produced mainly C2H4, CH4 and H2. The total amount of flammable gases formed in Voil (vegetable oil) is about 7.5 time lower than in MOL. It has also been found that the lacquer coating of the silicon steel sheet does not change the mechanism of gas formation processes in the investigated oils, as well as the fact that the oxygen content of the investigated oils decreases monotonously during the thermal treatment applied due to either the formation of CO2 and CO and the oxidation processes of investigated lacquers.

Deformation Capacity of a Ternary Magnesium Alloy in a Gas-Forming Process at Elevated Temperatures

An experimental ternary magnesium alloy, Mg-2Zn-2Ce, has been investigated. The attention was focused on the possibility of using this alloy for an unconventional sheet-forming process based on a flexible medium (gas-forming) for applications where weight-saving and complex shapes are required. Free inflation tests were performed at temperatures ranging from 350°C to 450°C, employing either a constant forming gas pressure or pressure jumps during the same test in order to evaluate the strain rate sensitivity, m, of the material. Interrupted free inflation tests at known dome heights were also conducted to investigate both the strain and the microstructural evolution. In addition, the texture behavior of the alloy was studied after hot rolling, revealing a weak deformation texture. Even though the material was in the as-cast condition, the alloy showed a good deformation capacity and contribution due to grain boundary sliding, indicating a potential for superplastic deformation.

Hydro-Liquefaction of Tile-Like Barzas Coals in the Presence of Some Transition Metal Additives

Using a laboratory micro-autoclave (of ~ 20 cm3 volume), the effects of transition metal additives (MoO3, Fe2O3 and commercial AlCoMo catalyst) on the thermal transformations of tile-like Barzas coals (sapromixites) in a hydrogen medium at T ~ 475°C and P ~ 6.0-7.5 MPa have been studied. It has been shown that catalytic additives under investigation somewhat suppress gas formation processes, facilitating the increase in H/C atomic ratios and in the amount of alkyl-containing structures in resin-like solid products of Barzas coal hydro-liquefaction. Maximal yields of “coal liquids” (maltenes + asphaltenes) (~ 35 wt.%, daf basis) were obtained during the heat treatment of sapromixites in the presence of bb1 wt.% MoO3.