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Petroleum coke is one of the waste products generated in the oil refining industry that can be used as fuel in energetics. However, the low volatile matter content and graphite-like structure of petroleum coke are the reasons for its high ignition temperature and combustion complexity. In this research, petroleum coke combustion and oxidation kinetics in the presence of metal catalysts were investigated. To evaluate the effect of the catalyst on the ignition temperature and the apparent activation energy, a new approach of a “fixed fluidized bed” was proposed. In this mode, petroleum coke particles spaced from each other by inert quartz powder kind of “freeze” in the porous layer. This regime allows us to determine the ignition temperature of petroleum coke particles in the static mode by differential thermography and calculate the activation energy by gas analysis. Organic and inorganic salts of copper, iron, and cerium are used as catalysts for petroleum coke combustion. A series of experiments were carried out in the porous media thermo-effect cell (PMTEC) and on a thermogravimetric (TG) analyzer. The kinetics of the combustion processes was calculated by Kissinger–Akahira–Sunose and Ozawa–Flynn–Wall methods. The results obtained in the “fixed bed” mode showed that the ignition temperature and the average apparent activation energy significantly decreased in the presence of CuCl2 and FeCl3. The results obtained by the new approach were compared with the results of the thermogravimetric analysis.

Messoyakhskoye field, operated by Gazprom Neft, is currently experiencing gas channeling from gas cap in production wells because of strong heterogeneity. Foam for a long has been considered as a good candidate for gas blocking, (Svorstol I. et al., 1996), (Hanssen, J. E., & Dalland, M. 1994), (Aarra, M. G. et al., 1996). However, foam injection for gas blocking in injection well is different from that in production well, where it is necessary to selectively and long-term impact on gas-saturated highly permeable areas without affecting the phase permeability of oil in the reservoir. This paper provides detailed laboratory studies that show how to determine suitable foam systems for gas blocking in production well. For gas blocking in production well, a long half-life time is required to sustain stable foam because a continuous shear of surfactant solution/gas can't be achieved like in injection well. Therefore, reinforced foam by polymer is chosen. Four polymer stabilizers and five foam agents were evaluated using bulk test to determine foaming ability, foam stability, and effect of oil by comparing foam rate and half-life time to determine the suitable foam system. Furthermore, filtration experiments were conducted at reservoir conditions to determine the optimal injection mode by evaluating apparent viscosity, breakthrough pressure gradient, resistance factor, and residual resistance factor. Polymer can significantly improve half-life time (increase foam stability), and the higher the polymer concentration, the longer the half-life time. But simultaneously, a high polymer concentration will increase the initial viscosity of solution, which not only decreases the foam rate, but also increases difficulties in injection. Therefore, an optimal polymer concentration of about 0.15-0.2 wt% is determined considering all these influences. Filtration experiments showed that the apparent viscosity in core first increased and then deceased with foam quality (the ratio of gas volume to foam volume (gas + liquid). The optimal injection mode is co-injection of surfactant/polymer solution and gas to in-situ generate foam at the optimal foam quality of about 0.65. Filtration experiments on the different permeability cores showed that gas-blocking ability of polymer reinforced foam is better in high-permeability cores, which is beneficial for blocking high permeability zone. It should be also noted that under a certain ratio of oil to foam solution (about lower than 1 to 1), the presence of oil slowly decreased foam rate with increasing oil volume, but significantly increased half -life time, which is favorable for foam treatment in production well. This work highlights the difference between foam injection for gas blocking in production well and injection well, and emphasizes the use of polymer reinforced foam. Moreover, this work shows systematic experimental methods for choosing suitable foam systems for gas blocking in production well considering different factors, which provides a guide regarding what kinds of foaming agents and polymer stabilizers should be used and how to evaluate them for designing a pilot application.

In-situ combustion (ISC) is an effective thermal enhanced oil recovery method. However, it is still not widely implemented in oilfields. One of the factors limiting the wide application of ISC is the challenge in its simulation and prediction. In this work, the oxidation experiments of maltenes and asphaltenes in reservoir rock were performed in the porous media thermo-effect cell (PMTEC) to establish a simplified reaction model based on non-isothermal measurements and to use it in numerical simulation of ISC process. It was found that the oxidation reaction process of oil fractions can be divided into different regions depending on generated self-energy rate and oxygen consumption rates that is up to the temperature. In order to propagate reactions from one mode to another, a specific oxygen consumption per unit mass of oil fractions is required. The average oxygen requirement for crossing LTOad (low temperature oxidation, oxygen addition reactions) boundary into LTC (low temperature combustion) mode was 64 mgO2/g(maltenes) and 10.4 mgO2/g(asphaltenes). To propagate reactions into HTO mode from the LTC mode, it requires about 646 mgO2/g(asphaltenes) for asphaltenes fraction. Moreover, this characterization seems to be a key tool when designing air injection in field pilots. Additionally, it was revealed that asphaltenes are more exothermic and require lower oxygen uptake per unit of temperature increment in comparison to maltenes. Furthermore, the mass conversion data obtained from non-isothermal measurements of oil fractions allow for the estimation of the stoichiometry coefficients of two low temperature oxidation reactions, i.e. oxidation and cocking processes, which can be included into a numerical simulation model to replicate combustion tube (CT) results. The numerical simulation model reveals that the simplified reaction model from a 6-step into a 3-step reaction scheme can reproduce ignition process, temperature profiles, combustion velocity, and fluid production, which thus makes it suitable for the upscaled modelling of ISC.

This article describes the assessment of effectiveness of gel and foaming agents for gas shut-off treatments in horizontal wells. The research is carried out through the implementation of a complex of special laboratory studies and analysis of the results using numerical modeling methods. A list of necessary laboratory experiments to minimize risks when carrying out work to limit gas inflow has been formulated, and approaches to carrying it out have been described. The program includes: free volume studies, filtration on linear and parallel core models. The results confirm the importance of studying not only the agent's physical characteristics at the reservoir conditions, but their interaction with reservoir fluids. The influence of different agents on the mobility of gas and oil was assessed as a result of linear core flooding experiments. In addition, the filtration tests on parallel cores were carried out aimed to determining the saturation selectivity. The series of numerical calculations was performed for the subsequent determination of the technological and economic effects of the treatment with gas blockers.

Using copper stearate as catalysts, catalytic in-situ combustion (ISC) of heavy oil was studied by porous medium thermo-effect cell (PMTEC) and combustion tube experiments. Significant acceleration of combustion was observed in porous media in PMTEC when copper stearate was added. Copper stearate promoted fuel deposition and its combustion and made them occur easier in low temperature, thus shifting both low-temperature oxidation (LTO) and high-temperature oxidation (HTO) into lower temperatures, and even totally merge HTO into LTO in some conditions. We found that the promotion on fuel deposition by catalysts might be related to the change of H/C ratio in fuel. The improvement in the performance of ISC by copper stearate in combustion tube experiments mainly manifests in lower ignition temperature, lower H/C ratio, increased air/fuel ratio, higher oil recovery, and higher level of in-situ oil upgrading, which makes copper stearate a good candidate for catalyzing ISC in field application.

The combustion characteristics of two Xinjiang heavy oils were studied by the self-designed porous medium thermo-effect cell (PMTEC) that can monitor the temperature alterations caused by oxidation/combustion reactions occurring within a porous medium under dynamic air flow. The results indicated that the heavy oils encountered obvious low-temperature combustion (LTC) in the temperature range of about 280–360 °C, accompanied by a maximum temperature increase to roughly 600 °C and significant release of CO and CO2. Then, PMTEC was adopted to evaluate the effects of air injection rate and water saturation on crude oil combustion. The increase of the air injection rate was conducive to triggering the LTC reactions and enhancing the intensity of LTC. The highest air injection rate (1 L/min in this work) led to the occurrence of fairly intense LTC reactions, during which large amounts of oxygen and oil sample were consumed. The increase of water saturation produced a minor influence on the occurrence of LTC, but obviously weakened the intensity of LTC. In addition, the influence of four metallic salts on the combustion behavior of heavy oil was examined using PMTEC. Cobalt naphthenate exhibited the good catalytic effect for promoting the occurrence of LTC. The mixed catalyst (cobalt naphthenate + manganese naphthenate) was found to have a better catalytic performance than any used single metallic salt. This mixed catalyst has a good potential for application in in-situ combustion of the Xinjiang heavy oil.

This article presents the results of experimental modeling of heat and mass transfer processes in oil-containing media caused by natural thermal convection. In this research we designed the laboratory setup and obtained experimental data for single- and two-component liquids medium with different permeability. It was shown that the dynamic of the media heating and the value of the oil recovery coefficient obtained experimentally and numerically by using the CMG STARS program coincides well. It was found that the processes of heat and mass transfer occur most intensively when the temperature of the medium near the heater reaches the value equals to the boiling point of water. The heating of the zone around the heater occurs faster, if a medium has a lower permeability. The oil recovery coefficient reached 55% with an initial water saturation coefficient of 0.52 and other conditions which corresponded to Ashalchinskoye oil field, Republic of Tatarstan, Russian Federation. This result is in a good agreement with the numerical result calculated by the CMG STARS program.

While an ionization during laminar or turbulent combustion has been studied quite well, the ionization processes in pulsating combustion of gases not so well known. In this paper, pulsating combustion of propane-butane mixture with air and gas ionization in the vortex chamber is considered.

In this paper, the combustion of petroleum coke is investigated. It is established that fluctuations of gas in the Rijke tube excited when petroleum coke burns with propane-air mixture. It is shown that over time the mixture supply can be significantly reduced due to the intensification of coke combustion by oscillations.

The article describes the laboratory setup designed to study the combustion of multicomponent fuels, in particular methane-hydrogen fuel, with air. The setup simulates a boiler with a heat exchanger. The results of experimental simulation of the initial combustion regime optimization of propane-butane fuel according to the existing algorithm are developed.

Objectives: The article describes the method of defect location determination in the pipelines according to the analysis of their vibrio-acoustic signals. Methods: In particular, the timely detection of transported product leaks will prevent accidents and reduce environmental damage. The graphic programming environment Lab VIEW was used to implement the algorithm of leak search and identification as a working tool. Results: The description and the operation method are provided for the software developed by the authors to record and process the acoustic signals. Conclusion: The aim of the research is to develop methods of transported product leak search according to the analysis of acoustic signals. This work was supported by RFBR grant №.16-38-00261.

It is known that petroleum coke, a product of deep processing of oil, can be used as fuel in power boilers. The method of petroleum coke burning in a fluidized bed is the most optimal to complete its combustion. To improve the combustion characteristics of this fuel, we studied the influence of catalysts on the petroleum coke burning in the simulation mode of a stationary fluidized bed. The laboratory setup is described. The results of the experiments are given.

Pipelines of heat networks are an important element of heat supply to cities and industrial facilities. To increase the reliability of the operation of pipelines of heating networks, reducing the number of their accidents and increasing the economic parameters of transportation of heat energy, it is required to constantly increase the volumes and quality of complex diagnostics. The instruments currently used for the diagnosis of pipelines have many shortcomings. Among them, low reliability of detection of defects and subjectivity of decision-making, as well as lack of funds for diagnostics of pre-insulated pipelines (in polyurethane foam insulation). To simplify, accelerate and improve the reliability of monitoring the technical condition of pipelines, the authors set the goal of diagnosing the object of research using acoustic methods, using neural network technologies to process acoustic signals. The article describes experimental studies of pipelines of heating networks in polyurethane foam insulation with various sizes of defects and an analysis of the acoustic signals obtained at the same time is made. The frequency of natural oscillations of the pipeline is chosen as the determining parameter of the acoustic signal. To process and analyze the frequencies obtained as a result of the experiments, a neural network of back propagation of the error was constructed.The results of the classification of the neural network of back propagation of the error trained by the neural network showed its good ability to analyze unknown samples and a high degree of reliability of their recognition.

Using associated gas and waste oil refineries in thermal power plants, a complex problem due to the variability in fuel composition. This article explores the burning of hydrocarbon fuel in the case of an abrupt change in its specific combustion heat. Results of the analysis allowed developing a technique of stabilizing the rate of heat release, ensuring complete combustion of the fuel and its minimum flow.

When the length of the resonance tube is much less and order of the acoustic wavelength is studied. Experimental set-up with a multiport burner is considered. The "energy balance" method is used to calculate the frequency and amplitude of the gas oscillations. The results of measurements and calculations show that increasing the length of the resonance tube causes the excitation oscillation with a first lower frequency. Further, there are no oscillations. When the length of the resonance tube becomes the order of the wavelength, the second resonant frequency is excited. The calculation results are in good agreement with the experimental data.

It is known that associated petroleum gas and refinery waste can be used as fuel in thermal power plants. However, random changes in the composition of such fuels cause instability of the combustion process. This article explores the burning of hydrocarbon fuel in the case of long continuous change of its specific heat of combustion. The results of analysis were used to develop a technique of optimizing the combustion process, ensuring complete combustion of the fuel and its minimum flow.

This article explores the combustion of gaseous fuel in the case of an abrupt change of the specific heat of combustion. Analyzes the changes in the rate of heat when the fuel and air flows are constant. Defines the conditions for which retained the initial rate of heat release and optimal fuel-air ratio.