Petroleum Coke Combustion Research Articles

Process optimization, exergy analysis, and GHG emissions of ammonia production systems by gasification of high-sulfur petroleum coke with CO2 capture

High-sulfur petroleum coke is commonly used as a fuel because of its high carbon content and calorific value. Direct combustion of high-sulfur petroleum coke has the problem of emitting a lot of CO2 and sulfide. Gasification is an environmentally friendly way to utilize high-sulfur petroleum coke. Therefore, this study first established hydrogen production systems with CO2 capture through high-sulfur petroleum coke gasification. The hydrogen is then reacted with nitrogen from air separation unit for producing ammonia, which is easy to transport and store. After optimizing and analyzing the key parameters of the established models, exergy and life cycle GHG emissions analysis are carried out to evaluate the technical performance and environmental impact. In the system with an 85 % gasification conversion rate of petroleum coke, the ammonia production capacity, exergy efficiency, and GHG emissions are 2300 kmol/h, 45.39 %, and 1468 kg CO2-eq/t NH3. When the conversion rate is elevated by ten percentage points, the ammonia production and exergy efficiency are increased to 2664 kmol/h and 51.95 %, while the GHG emissions are only reduced by 85 kg CO2-eq/t NH3 since most of the CO2 produced by the system is captured. Improving the petroleum coke conversion rate can significantly increase the exergy efficiency of ammonia production system, but has little impact on reducing GHG emissions during the process.

Comparative study on the molecular evolution of changqing petroleum coke during air and pure oxygen combustion: A ReaxFF method analysis

Based on reactive force field (ReaxFF) simulation, the molecular evolution mechanism of air combustion simulation and pure oxygen combustion simulation of Changqing petroleum coke was studied. On the basis of the original petroleum coke molecular model, N2 and O2 molecules were added to construct the air combustion simulation model and the pure oxygen combustion simulation model respectively. The number of molecules, main products, and typical hydrocarbon gases in the two simulation results were analyzed by setting up the LAMMPS in. file. Finally, the molecular changes of pyrrole and pyridine were described. The results show that the main reaction interval of pure oxygen combustion is earlier than that of air combustion. In the main reaction temperature range, the reaction rate of pure oxygen combustion is higher than that of simulated air combustion. At 170 ps, the two simulations reaction speed is the fastest time point; Pyridine is more stable than pyrrole. The research on the distinction and comparison of two kinds of simulation has certain guiding significance for the clean utilization of petroleum coke combustion process in industry.

Towards a Mechanistic Understanding of the Slagging Propensities of Petroleum Coke: Lessons Learned from Its Co-Combustion with Natural Gas in Oxygen-Enriched Atmospheres

A Computational Fluid Dynamic study was carried out to match the measured outer ash deposition rates associated with the combustion of petroleum coke (PC)–natural gas in AIR and O2/CO2 (70/30 vol%, OXY70). The fly ash PSD associated with high-fixed-carbon, non-porous fuel was estimated using a shrinking sphere burnout model and employed in conjunction with particle kinetic energy (PKE), particle viscosity (µP), and a critical Weber-number-based capture criterion. Deposition rate predictions were sensitive to the fly ash composition employed for estimating µP due to the significant enrichment of Fe in the deposits. Predictions were insensitive to the specific µP model formulation employed or whether the V2O5 in the ash was assumed to play the role of a glass former or a glass modifier. OXY70 scenario impaction rates were significantly lower than the measured deposition rates when the fly ash PSD associated with the AIR scenario was employed in the calculations. This necessitated an ad hoc modification of the OXY70 fly ash PSD to a coarser range to match the measurements and attributing it to agglomeration resulting from longer residence times and higher temperatures. This shift in PSD was in line with AIR and OXY70 fly ash PSD measurements reported previously.

Environmental assessment of asphalt mixtures modified with polymer coated rubber from scrap tires

Polymer coated rubber (PCR) is an engineered crumb rubber developed to address the drawbacks of regular crumb rubber in asphalt mixtures, such as the absorption of asphalt binder and premature cracking. Assessing the use of PCR using life cycle assessment (LCA) is important to evaluate whether its use lowers the environmental impact of asphalt mixtures. In LCA, the choice of allocation procedure significantly impacts the results. The cut-off method is often used in LCA studies of products containing recycled materials. The objectives of this work were to evaluate: i) if asphalt mixtures modified with PCR had lower environmental impact than mixtures modified with synthetic polymers, ii) if using more PCR decreased the environmental impact of the asphalt mixtures, iii) if the results changed by using different allocations methods, and finally, iv) if the environmental impact of asphalt mixtures changed when considering the long-term mechanical performance of the blends. In this work, the global warming potential (GWP), fossil depletion, and cumulative energy demand of one ton of asphalt mixture were calculated using the cut-off method, economic allocation, and system expansion. For the system expansion, the recovery energy in cement kilns from scrap tires was compared to burning petroleum coke or natural gas. The LCA of asphalt mixtures modified with two amounts of PCR (0.5% and 1% by weight of total mixture) compared to the synthetic polymer styrene-butadiene-styrene (SBS) was performed by including results of the experimental investigation (asphalt mixture design and mechanical testing conducted in the asphalt laboratory at Michigan State University). Results were different based on the allocation method considered. Overall, the GWP of PCR 0.5% and PCR 1% mixtures was lower than the SBS mixture, except in one case. The GWP of PCR 1% was 2% higher than the SBS mix when petroleum coke was used in the system expansion. Adding more PCR did not necessarily increase the environmental benefits. PCR 1% had a higher GWP than PCR 0.5% (2.6%, 2.7%, and 6.3% by using cut-off, economic allocation, and system expansion, respectively), except for the system expansion using natural gas as a replacement, which was 3.7% lower than the PCR 0.5%. However, the system expansion with natural gas had the lowest GWP compared to the other methods. On the contrary, the system expansion considering petroleum coke had the highest CO2eq emissions among all the methods used. The GWP of PCR 0.5% and PCR 1% was similar by using cut-off and economic allocation. As the cement industry transition to low-carbon energy, the carbon footprint associated with using scrap tires in pavements will decrease when using system expansion, while it will remain the same with the cut-off method. Considering the mechanical performance of the mixtures, the GWP for the pavement with 0.5% PCR was 8.04% lower over its service life than the synthetic polymer blend.

Technical and life cycle performance comparison between petroleum coke chemical looping combustion and oxy-combustion combining with advanced steam cycles for power generation processes

Inferior petroleum coke is attractive to be used in power generation industry since it has the advantage of high calorific value. To address the environmental problem of petroleum coke combustion for power generation, this paper establishes a process model of petroleum coke chemical looping combustion (CLC) and compares its performance with that of a petroleum coke oxy-combustion (OCB). The results show that CO2 capture rate of the CLC and OCB both reach about 100%. Under the petroleum coke conversion rate of 70%, the net electrical efficiencies of the petroleum coke CLC and OCB are 28.61% and 24.68%. The life cycle energy consumption and GHG emission of the CLC and OCB are 12.08/12.76 GJ/MWh and 338.03/397.91 kg CO2 eq/MWh, respectively. Compared with the sub-critical steam cycle in the above base case, the net electrical efficiencies of the CLC integrated with supercritical and ultra-supercritical cycles are increased by 0.93 and 1.53 percentages points, while their life cycle energy consumption and GHG emission are decreased by 0.31/0.49 GJ/MWh and 5.85/10.34 kg CO2 eq/MWh. When the conversion rate increases from 70% to 95%, the net electrical efficiencies of the CLC process are increased to 39.71/40.97/41.84%, and their life cycle results are decreased to 9.32/9.09/8.95 GJ/MWh and 300.85/296.20/292.07 kg CO2 eq/MWh. Therefore, improving conversion rate of the CLC and its coupling with advanced steam cycles for power generation are important for clean and efficient utilization of inferior petroleum coke.

Assessment of combustion characteristics of high ash Indian coal, petroleum coke and their blends for cement industry using TGA

This work investigates the combustion analysis of coal, petroleum coke and their blends. Coal and petroleum coke were characterized by proximate analysis, ultimate analysis, gross calorific value determination and ash analysis. Combustion performance of parent fuels and their blends were evaluated by thermogravimetric analysis followed by the analysis of different characteristics parameters, namely ignition temperature, peak temperature, burnout temperature and combustion efficiency. Results signify that petroleum coke has poor combustion characteristics compared to coal. After the rise in petroleum coke from 10 to 50 mass %, ignition temperature reduced from 413 to 385 °C, while insignificant variations occurred in peak temperature and burnout temperature. Such observations show natural reduction in ignition characteristics without significant modification in coal's burning profile. Combustion efficiency at 450 °C reduced from 46.18% to 34.77% as petroleum coke increased from 10 to 50 mass %, signifying decline in the combustion properties of coal. Kinetic analysis shows that petroleum coke has the maximum activation energy (182.11 kJ/mol) than coal (84.84 kJ/mol). Analysis of changes in enthalpy, Gibbs free energy and entropy inferred that individual combustion of both coal and petroleum coke is difficult, while blends have improved combustion characteristics than petroleum coke.

Combustion and gasification properties of petroleum coke and its pyrolytic semi-coke

In order to make full use of petroleum coke, isothermal pyrolysis experiments were conducted first, and then combustion characteristics at different oxygen concentrations and gasification properties of petroleum coke and its semi-coke were investigated. Results shown that when the pyrolysis temperature increased from 550 °C to 750 °C, the gas production increased from 31.6 mL/g to 192.8 mL/g. According to XRD results, the graphitization degree of semi-coke first decreased and then increased, and it was the lowest at 650 °C. Fitting results indicated that Avrami-Erofeev equation has the best linear correlation with combustion process. When the oxygen concentration increases from 21% to 80%, the combustion performance of PC, SC-550, and SC-750 increases gradually, and the SC-600, SC-650 and SC-700 reach the maximum at an oxygen concentration of 60%. Affected by the reduction of volatile matter and the change of graphitization degree, samples are divided into two types during the gasification process: the gasification rate changes obviously and relatively keeping stable. The gasification rate of semi-coke was higher than that of petroleum coke and negatively correlated with the degree of graphitization. Combustion with increased oxygen concentration and gasification with pre-pyrolysis are beneficial to the thermal conversion utilization of petroleum coke.

Sulfur Evolution and Capture Behavior by a Solid Waste of Red Mud during Chemical Looping Combustion of Petroleum Coke

The sulfur evolution behavior during the chemical looping combustion (CLC) process of petroleum coke was investigated in a fluidized bed reactor with a low-cost solid waste of red mud as the oxygen carrier. Effects of temperature, oxygen carrier, and potassium catalyst addition on sulfur release were investigated, and H2S oxidization kinetics with the red mud and the effect of elements in the red mud on sulfur conversion were evaluated in detail. The red mud oxygen carrier had a promoting effect on H2S generation and thus enhanced sulfur conversion. The addition of potassium remarkably accelerated carbon conversion due to its catalytic effect. Meanwhile, it promoted H2 generation and then enhanced the generation of H2S. The addition of potassium into the process could weaken the release of gaseous sulfur but had no obvious negative influence on the reactivity of the red mud oxygen carrier. The experiment H2S interaction with the red mud suggested that the conversion of H2S to SO2 decreased with increasing temperature. The red mud has a low ability to oxidize H2S to SO2 but a high reactivity to capture sulfur-containing gases. Solid sulfur-containing products such as CaSO4 and Fe3S4 as well as K2S2 in the case of K addition into the process were detected.

Effect of CaO/Fe2O3 on ash fusibility during petroleum coke gasification and combustion

Ash fusibility is closely related to ash melting, sintering and slagging, which is commonly used to guide the utilization of petroleum coke in boiler and gasifier. Calcium (Ca) and iron (Fe) show significant influence on the ash fusibility of petroleum coke. To quantify the influence of CaO/Fe2O3 mass ratio on petroleum coke ash fusibility, ash fusion temperatures (AFTs) analysis, X-ray diffraction (XRD), and FactSage were applied to investigate the characteristics of petroleum coke ash fusibility with various CaO/Fe2O3 mass ratios. The results showed that AFTs were closely associated with the CaO/Fe2O3 ratio and showed different performances in different atmospheres. In the reducing atmosphere, with the increasing of CaO/Fe2O3 ratio, the AFTs presented in turn a rapid decrease (from 0 to 2) and a smooth region (from 2 to ∞). The rapid decrease of AFTs was mainly attributed to the disappearance of high-melting point coulsonite (FeV2O4) and the formation of low temperature eutectics anorthite (CaAl2Si2O8) and gehlenite (Ca2Al2SiO2). The formation of high-melting point calcium orthosilicate (Ca2SiO4) inhibited the formation of CaAl2Si2O8/Ca2Al2SiO2 to keep the AFTs at a stable level. In the oxidizing atmosphere, with the increasing of CaO/Fe2O3 ratio, the AFTs presented in turn a rapid decrease (from 0 to 1), a smooth region (from 1 to 5), and a fast decrease once again (from 5 to ∞), respectively. The decline of AFTs was attributed to the substitution of NiFe2O4 by fusible minerals (Ca2V2O7/CaAl2Si2O8). The synergy effect of the refractory SiO2 and fusible minerals prevented the further decline of the AFTs.

Analyzing Relationships of Conductivity and Alkalinity Using Historical Datasets from Streams in Northern Alberta, Canada

Many measurements, tools, and approaches are used to identify and track the influence of human activities on the physicochemical status of streams. Commonly, chemical concentrations are utilized, but in some areas, such as downstream of coal mines, capacity indices such as specific conductivity have also been used to estimate exposure and risk. However, straightforward tools such as conductivity may not identify human influences in areas with saline groundwater inputs, diffuse exposure pathways, and few discharges of industrial wastewater. Researchers have further suggested in conductivity relative to alkalinity may also reveal human influences, but little has been done to evaluate the utility and necessity of this approach. Using data from 16 example sites in the Peace, Athabasca, and Slave Rivers in northern Alberta (but focusing on tributaries in Canada’s oil sands region) available from multiple regional, provincial, and national monitoring programs, we calculated residual conductivity and determined if it could identify the potential influence of human activity on streams in northern Alberta. To account for unequal sampling intervals within the compiled datasets, but also to include multiple covariates, we calculated residual conductivity using the Generalized Estimating Equation (GEE). The Pearson residuals of the GEEs were then plotted over time along with three smoothers (two locally weighted regressions and one General Additive Model) and a linear model to estimate temporal patterns remaining relative to known changes in human activity in the region or adjacent to the study locations. Although there are some inconsistencies in the results and large gaps in the data at some sites, many increases in residual conductivity correspond with known events in northern Alberta, including the potential influence of site preparation at oil sands mines, reductions in particulate emissions, mining, spills, petroleum coke combustion at one oil sands plant, and hydroelectric development in the Peace basin. Some differences in raw conductivity measurements over time were also indicated. Overall, these analyses suggest residual conductivity may identify broad influences of human activity and be a suitable tool for augmenting broad surveillance monitoring of water bodies alongside current approaches. However, some anomalous increases without apparent explanations were also observed suggesting changes in residual conductivity may also be well-suited for prompting additional and more detailed studies or analyses of existing data.

Effects of Mustard Husk, Wheat Straw, and Flaxseed Residue Blending on Combustion Behavior of High Ash Coal and Petroleum Coke Blends

Abstract This present work reports the combustion studies of coal, petroleum coke (PC) and biomass blends to assess the effects of the mustard husk (MH), wheat straw (WS), and flaxseed residue (FR) blending toward improvement of coal combustion characteristics. Ignition temperature (TS), maximum temperature (TP), burnout temperature (TC), activation energy (AE), and thermodynamic parameters (ΔH, ΔG, and ΔS) were analyzed to evaluate the impact of biomass and PC blending on coal combustion. Experimental results indicate that coal and PC have inferior combustion characteristics compared to MH, WS, and FR. With the increase in WS content in blends from 10 to 30%, TS reduced from 371 to 258 °C and TP decreased from 487 to 481 °C, inferring substantial enhancements in combustion properties. Kinetic analysis inferred that blended fuel combustion could be explained mostly using reaction models, followed by diffusion-controlled and contracting sphere models. Overall, with the increase in FR mass in blends from 10 to 30%, AE decreased from 108.97 kJ/mol to 70.15 kJ/mol signifying ease of combustion. Analysis of synergistic effects infers that higher biomass addition improves coal and PC blends’ combustion behavior through catalytic effects of alkali mineral matters present in biomass. Calculation of thermodynamic parameters signified that combustion of coal and PC is challenging than biomasses; however, blending of biomass makes the combustion process easier.

Improvement of Coal and Petroleum Coke Combustion in a Fluidized Bed by Using Ilmenite Ore as Bed Material

Improvement of Coal and Petroleum Coke Combustion in a Fluidized Bed by Using Ilmenite Ore as Bed Material

Effect of Cao/Fe2o3 on Ash Fusibility During Petroleum Coke Gasification and Combustion

Effect of Cao/Fe2o3 on Ash Fusibility During Petroleum Coke Gasification and Combustion

Energy consumption and CO2 emissions of petroleum coke-to-methanol with/without carbon capture using process modeling and life cycle analysis

Petroleum coke is an important by-product of oil refineries. It is characterized by high carbon content and calorific value with increasing sulfur content due to the use of the inferior crude oil. The application of petroleum coke combustion will inevitably produce a large amount of greenhouse gas emissions. Gasification technology can efficiently convert it to syngas and then for methanol production. However, the petroleum coke-to-methanol also faces serious CO2 emissions when adjusting syngas composition. Therefore, this study establishes the model of the petroleum coke-to-methanol with/without carbon capture and compares their energy consumption and CO2 emissions from the production and life cycle aspect. The CO2 emissions of the petroleum coke conversion rates of 75%, 85%, and 95% without carbon capture are 2439 kg/t, 2269 kg/t, 2146 kg/t with exergy efficiencies of 38.35%, 45.31%, and 52.23%. With the help of the carbon capture devices, their CO2 emissions are reduced to 316 kg/t, 297 kg/t, and 285 kg/t with decreasing exergy efficiencies by about 1%. From the aspect of life cycle, the greenhouse gas emissions of the petroleum coke-to-methanol are 3602, 3299, and 3077 kg CO2 eq/t, which are reduced by about 54.58–55.79% with involving carbon capture.

Thermodynamic Design of Organic Rankine Cycle (ORC) Based on Petroleum Coke Combustion

Thermodynamic analysis of Organic Rankine Cycle (ORC) was performed in this work. The Petroleum Coke burner provided the required heat flux for the Butane Boiler. The simulation of pet-coke combustion was carried out by using Fire Dynamics Simulator software (FDS) version 5.0. Validation of the FDS calculation results was carried out by comparing the temperature of the gaseous mixture and CO2 mole fractions to the literature. It was discovered that they are similar to those reported in the literature. An Artificial Intelligence (AI) time forecasting analysis was performed on this work. The AI algorithm was applied to the temperature and soot sensor readings. Two Python libraries were applied in order to forecast the time behaviour of the thermocouple readings: Statistical model—ARIMA (Auto-Regressive Integrated Moving Average) and KERAS—deep learning library. ARIMA is a class of model that captures a suite of different standard temporal structures in time series data. Keras is a python library applied for deep learning and runs on top of Tensor-Flow. It has been developed in order to perform deep learning models as fast and easily as possible for research and development. The model accuracy and model loss plot shows comparable performance (train and test). Butane has been employed as a working fluid in the ORC. Butane is considered one of the best pure fluids in terms of exergy efficiency. It has low specific radiative forcing (RF) compared to Ethane and Propane. Moreover, it has zero ozone depletion potential and low Global Warming Potential. It is considered flammable, highly stable and non-corrosive. The thermodynamic properties of Butane needed to evaluate the heat rate and the power were calculated by applying the ASIMPTOTE online thermodynamic calculator. It was shown that the calculated net power of the ORC cycle is similar to the net power reported in the literature (relative error of 4.8%). The proposed ORC energetic system obeys the first and second laws of thermodynamics. The thermal efficiency of the cycle is 20.4%.

Catalytic combustion behaviors of petroleum coke with hematite catalyst in a micro fluidized bed thermogravimetric analysis

Both conventional TGA and fluidized bed have some inherent limitations in the accurate measurement of gas–solid reaction. To characterize the gas–solid process under the fluidization state, a micro fluidized bed thermogravimetric analysis (MFB-TGA) was developed based on the real-time measurement with precision of 0.1 mg mass, 0.1°C temperature, and 0.01 kPa pressure. In this study, we preliminarily applied the MFB-TGA in evaluating catalytic combustion of petroleum coke with respect to deducing Fe2O3 catalytic mechanism, lattice oxygen migration pathway, and apparent combustion kinetics. The measurement stability of MFB-TGA was impacted by various factors, such as inhomogeneous temperature distribution and slight gas disturbance. Even char combustion heat could destabilize the weight signal by inducing vigorous particle collisions. The lightweight design and several structural optimizations were implemented to improve the MFB-TGA performance with the result of realizing smooth weight loss curves with 0.1 mg errors during the entire experiment. The experimental analysis revealed that the catalytic mechanism of hematite was identified as CO homogeneous catalysis. Hematite accelerated the char combustion rate by intensifying the driving force of bulk oxygen diffusion to the carbon surface. It served as an oxygen carrier, transferring lattice oxygen to oxidize carbon monoxide surrounding char particles. The apparent intrinsic kinetics of 33.73 kJ/mol was determined by the isothermal differential approach, which was lower than the published results measured in regular TGA. The zero-order model exhibited an excellent linear correlation in describing combustion behaviors based on a function fitting process. The MFB-TGA had the potential for extensive application by providing a reliable and straightforward method in characterizing gas–solid reactions under a fluidization state.

Petroleum Coke Combustion in Fixed Fluidized Bed Mode in the Presence of Metal Catalysts.

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.

Techno-Economic Analysis of Pressurized Oxy-Fuel Combustion of Petroleum Coke

Petroleum coke (petcoke) is a by-product of heavy petroleum refining, with heating values comparable to that of coal. It is readily available in oil-producing countries such as the United States of America (USA) and the Kingdom of Saudi Arabia (KSA) at minimum costs and can be used as an inexpensive fossil fuel for power generation. Oxy-petcoke combustion is an attractive CO2 capture option as it avoids the use of additional absorption units and chemicals, and results in a CO2 + H2O flue gas stream that is compressed and dehydrated in a CO2 capture and purification unit (CO2CPU). The additional cost of the CO2CPU can be reduced through high pressure combustion. Hence, this paper reports a techno-economic analysis of an oxy-petcoke plant with CO2 capture simulated at pressures between 1 and 15 bars in Aspen PlusTM based on USA and KSA scenarios. Operating at high pressures leads to reduced equipment sizes and numbers of units, specifically compressors in CO2CPU, resulting in increased efficiencies and decreased costs. An optimum pressure of ~10 bars was found to maximize the plant efficiency (~29.7%) and minimize the levelized cost of electricity (LCOE), cost of CO2 avoided and cost of CO2 captured for both the USA and KSA scenarios. The LCOE was found to be moderately sensitive to changes in the capital cost (~0.7% per %) and increases in cost of petcoke (~0.5% per USD/tonne) and insensitive to the costs of labour, utilities and waste treatment.

Effect of limestone addition on no emission during petroleum coke combustion in CFBB

Combustion in a circulating fluidzed bed boiler (CFBB) for power generation is the most effective pathway for petroleum coke utilization, and during which, limestone is usually employed to capture SO2 to meet the emission demand. However, it also was found accidentally that limestone can play a very active role to reduce NO emission. To investigate the effect mechanism of limestone addition on NO reduction, laboratory and industrial experiments were performed in a lab-scale circulating fluidzed bed (CFB) reactor and industrial CFBB, respectively. The results showed that the reduction of NO with limestone addition was caused by the catalysis of CaSO4 on the reduction reaction of NO by CO into N2 in the dilute phase of the CFBB. Then, the catalysis of CaSO4 on the reduction reaction of NO and CO was further experimentally studied in a horizontal tube furnace. CaSO4 was found to be a strong catalyst on the reaction with a reduction rate of NO up to 99%.

Pulsating burning of petroleum coke in the Rijke tube

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.