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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.

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.

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.