Carbon Burning Research Articles

Thermal activation and mechanical properties of high alumina coal gangue as auxiliary cementitious admixture

In order to use high alumina coal gangue as auxiliary cementitious admixture via a simple and convenient thermal activation technique, the thermal transformation, mineral phase transformation and structure changes of coal gangue at calcining temperatures of 500–1000 °C were analyzed using x-ray diffraction (XRD), differential thermal Analysis (DTA), thermogravimetry (TG), infrared analysis (IR) and scanning electron microscope (SEM). The mechanical properties of cement mortar with 30% coal gangue auxiliary cementitious admixture were also measured to determine the optimal calcining temperature. As calcining temperature was increased, the coal gangue experienced the following transformations: carbon combustion, dehydroxylation, metakaolin transformation and mullite transformation. The cement mortar with coal gangue auxiliary cementitious admixture calcined at 700 °C presented the highest 28-d flexural and compressive strength, increasing by 8.27% and 11.85% respectively as compared with the benchmark cement mortar. The maximum dosage of coal gangue auxiliary cementitious admixture in cement mortar was further identified to be less than 30% by mechanical properties testing. The activity of high alumina coal gangues at different calcining temperatures was explained from the view points of hydration degree and products. The present investigation can provide a useful reference to utilize high alumina coal gangue as auxiliary cementitious admixture by means of a simple thermal activation at 700 °C.

JWST MIRI/Medium Resolution Spectrograph (MRS) Observations and Spectral Models of the Underluminous Type Ia Supernova 2022xkq

We present a JWST mid-infrared (MIR) spectrum of the underluminous Type Ia Supernova (SN Ia) 2022xkq, obtained with the medium-resolution spectrometer on the Mid-Infrared Instrument (MIRI) ∼130 days post-explosion. We identify the first MIR lines beyond 14 μm in SN Ia observations. We find features unique to underluminous SNe Ia, including the following: isolated emission of stable Ni, strong blends of [Ti ii], and large ratios of singly ionized to doubly ionized species in both [Ar] and [Co]. Comparisons to normal-luminosity SNe Ia spectra at similar phases show a tentative trend between the width of the [Co iii] 11.888 μm feature and the SN light-curve shape. Using non-LTE-multi-dimensional radiation hydro simulations and the observed electron capture elements, we constrain the mass of the exploding WD. The best-fitting model shows that SN 2022xkq is consistent with an off-center delayed-detonation explosion of a near-Chandrasekhar mass WD ( MWD ≈1.37 M ⊙) of high central density (ρ c ≥ 2.0 × 109 g cm−3) seen equator-on, which produced M(56Ni) =0.324 M ⊙ and M(58Ni) ≥0.06 M ⊙. The observed line widths are consistent with the overall abundance distribution; and the narrow stable Ni lines indicate little to no mixing in the central regions, favoring central ignition of subsonic carbon burning followed by an off-center deflagration-to-detonation transition beginning at a single point. Additional observations may further constrain the physics revealing the presence of additional species including Cr and Mn. Our work demonstrates the power of using the full coverage of MIRI in combination with detailed modeling to elucidate the physics of SNe Ia at a level not previously possible.

Cluster effects on low-energy carbon burning

Carbon burning is crucial for the fate of massive stars and element creation in the Universe. Its understanding at stellar energies is a great theoretical challenge, as carbon fusion is a multidimensional quantum tunneling process affected by resonances whose origin is not fully understood yet. Simplified quantum dynamical coupled-channels calculations are presented, suggesting that clustering in the intermediate nuclear molecule is a source of fusion resonances.

Thermal Activation of High-Alumina Coal Gangue Auxiliary Cementitious Admixture: Thermal Transformation, Calcining Product Formation and Mechanical Properties.

In this paper, a new preparation technology is developed to make high-alumina coal gangue (HACG) auxiliary cementitious admixture by calcining HACG-Ca(OH)2 (CH) mixture. HACG powders mixed with 20 wt.% CH were calcined within a temperature range of 600-900 °C, and the thermal transformation and mineral phase formation were analyzed. The hydration reaction between activated HACG-CH mixture and cement was also investigated. The results showed that HACG experienced a conventional transformation from kaolinite to metakaolin at 600 °C and finally to mullite at 900 °C, whereas CH underwent an unexpected transformation process from CH to CaO, then to CaCO3, and finally to CaO again. These substances' states were associated with the dehydroxylation of CH, the chemical reaction between CaO and CO2 generating from the combustion of carbon in HACG, and the decomposition of CaCO3, respectively. It is the formation of a large amount of CaO above 800 °C that favors the formation of hydratable products containing Al2O3 in the calcining process and C-A-H gel in the hydration process. The mechanical properties of HACG-cement mortar specimens were measured, from which the optimal calcination temperature of 850 °C was determined. As compared with pure cement mortar specimens, the maximum 28-d flexural and compressive strengths of HACG-cement mortar specimens increased by 5.4% and 38.2%, respectively.

Reactivity and catalytic effect of coals during combustion: Thermogravimetric analysis

Catalytic coal combustion is a promising technology to realize efficient utilization of coal, however, the catalysis in the coal combustion process is unclear. This paper focused on the effects of two type catalysts (metal oxides and metal compounds) on the combustion reactivity of lignite, bituminous coal and anthracite using thermogravimetric analyzer, and discussed the catalytic mechanisms combining with catalytic thermal decomposition and catalytic char combustion. All catalysts decreased the ignition temperature and burnout temperature of coals to the extent of 0.25–81.25 °C, 24.75–73.25 °C, and increased the exothermic values. The catalytic effect was influenced by coal rank and had the greatest promoting effect on anthracite. Besides, the pyrolysis conversion rates of coals were increased by catalysts, resulting in ignition advance and made the subsequent reaction easier. The results of catalytic char combustion showed that both catalysts significantly reduced the ignition temperature of char, the Na2CO3 had the best catalytic effect on fixed carbon combustion, while CaO mainly affected the release of volatile matter. Finally, the catalytic mechanism in coal combustion was discussed. This article aims to provide theoretical reference for the practical comprehensive application of coal catalytic combustion.

Simulation of waste tire gasification in bubbling fluidized bed by Aspen: Contribution ratio analysis

Waste tire gasification in a bubbling fluidized bed is a promising thermochemical conversion technology that not only utilize waste tire but also produce energy. To reveal the gasification performance of waste tire in a bubbling fluidized bed, two Aspen models were developed to simulate the effect of gasification agent types (such as air, steam, carbon dioxide and their mixtures), considering chemical reactions that reached thermodynamic equilibrium (CRTM) or were controlled by kinetics (CRK). The simulated gas compositions (H2, CO, CO2 and CH4) and lower heating value (LHV) were compared with experimental data under various operating conditions. The results showed that CRK model exhibited much better performance than the CRTM model. These two models were further utilized to analyze the effect of gasification agent type on gas composition and LHV. The contribution ratios of different chemical reactions were detailed analyzed, such as hydrogen combustion, carbon monoxide combustion, methane combustion, carbon combustion, steam gasification, water gas shift reaction and carbon dioxide gasification. The established Aspen model for waste tire gasification in a bubbling fluidized bed could be served as a guideline for selecting operation conditions to achieve high hydrogen composition, carbon conversion, and gas yield.

Fossil and Nonfossil Sources of Winter Organic Aerosols in the Regional Background Atmosphere of China.

Carbonaceous aerosols (CA) from anthropogenic emissions have been significantly reduced in urban China in recent years. However, the relative contributions of fossil and nonfossil sources to CA in rural and background regions of China remain unclear. In this study, the sources of different carbonaceous fractions in fine aerosols (PM2.5) from five background sites of the China Meteorological Administration Atmosphere Watch Network during the winter of 2019 and 2020 were quantified using radiocarbon (14C) and organic markers. The results showed that nonfossil sources contributed 44-69% to total carbon at these five background sites. Fossil fuel combustion was the predominant source of elemental carbon at all sites (73 ± 12%). Nonfossil sources dominated organic carbon (OC) in these background regions (61 ± 13%), with biomass burning or biogenic-derived secondary organic carbon (SOC) as the most important contributors. However, the relative fossil fuel source to OC in China (39 ± 13%) still exceeds those at other regional/background sites in Asia, Europe, and the USA. SOC dominated the fossil fuel-derived OC, highlighting the impact of regional transport from anthropogenic sources on background aerosol levels. It is therefore imperative to develop and implement aerosol reduction policies and technologies tailored to both the anthropogenic and biogenic emissions to mitigate the environmental and health risks of aerosol pollution across China.

Synthetic methane for closing the carbon loop: Comparative study of three carbon sources for remote carbon-neutral fuel synthetization

Achieving carbon neutrality is probably one of the most important challenges of the 21st century for our societies. Part of the solution to this challenge is to leverage renewable energies. However, these energy sources are often located far away from places that need the energy, and their availability is intermittent, which makes them challenging to work with. In this paper, we build upon the concept of Remote Renewable Energy Hubs (RREHs), which are hubs located at remote places with abundant renewable energy sources whose purpose is to produce carbon-neutral synthetic fuels. More precisely, we model and study the Energy Supply Chain (ESC) that would be required to provide a constant source of carbon-neutral synthetic methane, also called e-NG (electric Natural Gas) or e-methane (electric methane), in Belgium from an RREH located in Morocco. To be carbon neutral, a synthetic fuel has to be produced from existing carbon dioxide (CO2) that needs to be captured using either Direct Air Capture (DAC) or Post Combustion Carbon Capture (PCCC). In this work, we detail the impact of three different carbon sourcing configurations on the price of the e-methane delivered in Belgium. Our results show that sourcing CO2 through a combination of DAC and PCCC is more cost-effective, resulting in a cost of 146 €/MWh for e-methane delivered in Belgium, as opposed to relying solely on DAC, which leads to a cost of 158 €/MWh. Moreover, these scenarios are compared to a scenario where CO2 is captured in Morocco from a CO2 emitting asset that allow to deliver e-methane for a cost of 136 €/MWh.

Fire‐Induced Carbon Loss and Tree Mortality in Siberian Larch Forests

AbstractClimate change is intensifying the fire regime across Siberia, with the potential to alter carbon combustion and post‐fire carbon re‐accumulation trajectories. Few field‐based estimates of fire severity (e.g., carbon combustion and tree mortality) exist in Siberian larch forests (Larix spp.), which limits our ability to project how an intensified fire regime will affect regional and global climate feedbacks. Here, we present field‐based estimates of fire‐induced tree mortality and carbon loss in eastern Siberian larch forests. Our results suggest that fires in this region result in high tree mortality (means of 83% and 76% at Arctic and subarctic sites, respectively). In both absolute and relative terms, aboveground carbon loss following fire is higher in Siberian larch forests than in North America, but belowground carbon loss is considerably lower. This suggests fundamental differences in wildfire behavior and carbon dynamics between dominant vegetation types across the boreal biome.

An optimized heating source for heat-not-burn tobacco products through synergistic combustion of tobacco stalk and graphite carbon with K2CO3 catalyst.

Waste tobacco stalk is blended with graphite carbon to form a composite carbon source, which is a promising external heating system for heat-not-burn tobaccos. In the current work, the effects of tobacco stalk amounts and the catalyst K2CO3 on the co-combustion characteristics (i.e., the ignition temperature, burnout temperature, etc.) of graphite carbon were investigated. As a result, the ignition temperatures of the blend were determined by the tobacco straw, while the burnout temperature of the samples was reduced by approximately 60 °C due to the addition of a tobacco stalk. After the addition of K2CO3, the ignition temperatures of the mixture were further decreased by 2-7 °C since the ignition temperature of the tobacco stalk was difficult to further reduce after K2CO3 addition. Meanwhile, the burnout temperature can be reduced by 76-106 °C because the presence of K2CO3 can significantly improve the combustion of graphite carbon. In addition, the kinetic analysis revealed that during the release of volatile matter, the oxidation process accords with the first-order kinetic model, while in the combustion process of mixed carbon source, the combustion process can be described by the third-order kinetic model.

Post-treatment strategies for pyrophoric KOH-activated carbon nanofibres.

The effect of two atmospheric post-treatment conditions directly after the KOH activation of polyacrylonitrile-based nanofibres is studied in this work. As post-treatment different N2 : O2 flow conditions, namely high O2-flow and low O2-flow, are applied and their impact on occurring reactions and carbon nanofibres' properties is studied by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Raman spectroscopy, elemental analysis and CO2 and Ar gas adsorption. At high O2-flow conditions a pyrophoric effect was observed on the KOH-activated carbon nanofibers. Based on the obtained results from the TGA and DSC the pyrophoric effect is attributed to the oxidation reactions of metallic potassium formed during the KOH activation process and a consequent carbon combustion reaction. Suppression of this pyrophoric effect is achieved using the low O2-flow conditions due to a lower heat formation of the potassium oxidation and the absence of carbon combustion. Compared to the high O2-flow samples no partial destruction of the carbon nanofibers is observed in the SEM images. The determination of the adsorption isotherms, the surface area, the pore size distribution and the isosteric enthalpies of adsorption show the superior properties under low O2-flow conditions. The present micropore volume is increased from 0.424 cm3 g-1 at high O2-flow to 0.806 cm3 g-1 for low O2-flow samples, resulting in an increase of CO2 adsorption capacity of 38% up to 6.6 mmol g-1 at 1 bar. This significant improvement clearly points out the importance of considering highly exothermic potassium oxidation reactions and possible post-treatment strategies when applying KOH activation to electrospun carbon nanofiber materials.

Climate change must be factored into savanna carbon- management projects to avoid maladaptation: the case of worsening air pollution in western Top End of the Northern Territory, Australia

Savanna fires are a major source of greenhouse gas (GHG) and particulate pollution globally. Since mid-2006, an Australian Government carbon offset program has incentivised Northern Territory land managers to undertake early dry-season savanna burning with the aim of reducing late dry-season wildfires and associated GHG emissions. The focus of this study is addressing concern that savanna burning carbon abatement projects are causing worsening air pollution in the city of Darwin. Reconstructed concentrations of daily particulate matter of <2.5 μm (PM2.5) since the 1960s showed since 2000s a worsening in PM2.5 in the early dry season (May, June, July), some improvement in the late dry season (August, September, October) with little overall difference for the whole dry season. Remote-sensing PM2.5 estimates in Darwin were correlated with region-wide PM2.5 estimates during the early dry season. Remote-sensing analysis of area burned and intensity of fires since 2002 showed that savanna carbon projects have shifted burning to the early dry season and caused increases in fire intensity compared with non-project areas. Increased fire intensity appears to follow sharply declining fuel moisture, as well as management effects on carbon project areas, which have possibly undermined the efficacy of savanna burning projects in reducing GHG emissions. More thorough evaluation of underlying assumption of savanna burning carbon abatement in Australia and elsewhere in the world is required to avoid maladaptation, such as over-crediting, smoke pollution, and other environmental harms.

Fluidization-melting characteristics of fly ash from municipal solid waste incineration

Fly ash (FA) from municipal solid waste incineration contains hazardous substances such as dioxins, furans, and heavy metals. Melting FA has proved to be an effective method for reducing volume and mass, while also rendering the waste harmless. However, during the melting process, the addition of a fluxing agent with calorific value is currently necessary to increase melting capacity and reduce energy consumption, which presents a challenge. To tackle this issue, a fluidization-melting technology for a fuel/FA mixture is proposed, wherein a fuel source is employed in the melting process, producing ash that can serve as a fluxing agent. To test this approach, rice husk (RH) was utilized as fuel in a small-scale fluidization-melting test. The objective of this study was to examine the operation parameters of the platform and the characteristics of the resulting product, and to evaluate the harm reduction effect of the slag and its potential for resource utilization. The operating temperature was set at 690 °C in the thermal modification unit and at 1450 °C in the melting furnace, resulting in stable operation and continuous liquid slag discharge. The leaching toxicity of heavy metals in the obtained slag was lower than the standard limit, achieving harmless disposal of FA. However, the resource utilization potential of the obtained slag is limited due to its failure to meet the criteria of vitrified substance and environmental quality requirements. These limitations could be addressed by promoting the combustion of carbon in the melting furnace and accelerating the cooling rate of the slag in the quenching unit.

Experimental and modeling study of the combustion of ethyl methyl carbonate, a battery electrolyte

Ethyl methyl carbonate (EMC) is one of the main constituents of the electrolyte in lithium-ion batteries (LIBs). To understand better fire events involving LIBs and try to prevent them, the combustion of EMC was studied experimentally, and the results were analyzed using modern detailed kinetics models. Shock tubes were used to collect ignition delay times (IDTs) and CO time histories, while laminar flame speeds were measured in a closed vessel. All experiments were carried out near atmospheric pressure. The shock tube experiments were performed for three equivalence ratios (0.5, 1.0, and 2.0) with the IDTs measured with “fuel-air” mixtures and the CO spectroscopic laser measurements in mixtures highly diluted in 99.25% He/Ar. Comparisons with results obtained for other linear carbonates typically found in LIBs, such as dimethyl carbonate and diethyl carbonate, are also presented. Numerical predictions from recent detailed chemical kinetics mechanisms (Takahashi et al., 2022, Grégoire et al., 2023) did not capture well the combustion behavior of EMC in some of our conditions. Sensitivity analyses suggest that EMC decomposition reactions and subsequent combustion chemistry of the formed intermediates, i.e. methanol and ethylene, still need improvement.

Hydrothermal carbonisation of polyvinyl chloride in ethanol-water/water system for solid fuels: Dechlorination, characteristics analysis of hydrochar, and reaction path

Polyvinyl chloride (PVC) waste plastic is a typical solid waste. In this paper, the dechlorination and carbonization behavior of PVC in ethanol-water/water system under different process parameters (temperature, residence time, solid-liquid ratio) was studied, and hydrothermal carbon was characterized by SEM, elemental analysis, TG-DTG, XPS, Py-GC/MS. The results show that temperature is the key to the hydrothermal dechlorination of PVC, and the dechlorination efficiency of PVC is the highest by parameter optimization (220°C-90 min-10% S/D-80% E/D), which can reach 96.33 %. With the removal of Cl, the surface of the PVC matrix changed from full and smooth flocculent to honeycomb with uniform pore size distribution. Thermogravimetric analysis shows that the combustion of hydrochar can be divided into three stages: HCl precipitation and volatile combustion, semi-coke and coke combustion, and fixed carbon combustion. The combustion parameters and kinetic parameters of hydrochar were measured, and it was found that the hydrothermal carbonization of PVC at higher temperatures and ethanol-water ratio could improve the combustion performance of hydrochar. The highest calorific value can reach 36.68 MJ/mol. Py-GC/MS analyzed the distribution of the pyrolysis products, and alkylbenzene and aliphatic were the main products of pyrolysis. The structural analysis of hydrochar showed that C–C and CC accounted for the largest proportion, accompanied by a small amount of C–O and CO and trace C–Cl. The possible reaction mechanism of the hydrothermal carbonization of PVC was analyzed based on the distribution of functional groups and compound composition. This work provides an effective and sustainable method for the recycling of refractory chlorinated plastics.

Analysis of PM2.5 inorganic and organic constituents to resolve contributing sources in Seoul, South Korea and Beijing, China and their possible associations with cytokine IL-8

China and South Korea are the most polluted countries in East Asia due to significant urbanization and extensive industrial activities. As neighboring countries, collaborative management plans to maximize public health in both countries can be helpful in reducing transboundary air pollution. To support such planning, PM2.5 inorganic and organic species were determined in simultaneously collected PM2.5 integrated filters. The resulting data were used as inputs to positive matrix factorization, which identified nine sources at the ambient air monitoring sites in both sites. Secondary nitrate, secondary sulfate/oil combustion, soil, mobile, incinerator, biomass burning, and secondary organic carbon (SOC) were found to be sources at both sampling sites. Industry I and II were only identified in Seoul, whereas combustion and road dust sources were only identified in Beijing. A subset of samples was selected for exposure assessment. The expression levels of IL-8 were significantly higher in Beijing (167.7 pg/mL) than in Seoul (72.7 pg/mL). The associations between the PM2.5 chemical constituents and its contributing sources with PM2.5-induced inflammatory cytokine (interleukin-8, IL-8) levels in human bronchial epithelial cells were investigated. For Seoul, the soil followed by the secondary nitrate and the biomass burning showed increase with IL-8 production. However, for the Beijing, the secondary nitrate exhibited the highest association with IL-8 production and SOC and biomass burning showed modest increase with IL-8. As one of the highest contributing sources in both cities, secondary nitrate showed an association with IL-8 production. The soil source having the strongest association with IL-8 production was found only for Seoul, whereas SOC showed a modest association only for Beijing. This study can provide the scientific basis for identifying the sources to be prioritized for control to provide effective mitigation of particulate air pollution in each city and thereby improve public health.

Selective Adsorption of Gadolinium by Nitrogen-Doped Carboxymethylated Cellulose Nanocrystalline Carbon Aerogels Functionalized in the Ammonia-Urea System.

In this paper, an ammonia-urea system was developed to induce the shedding of carboxymethylcellulose carbon aerogels to form defects, and the specific surface area of the aerogels was significantly increased after carbonization, and the three-dimensional disordered pore structure of cellulose was preserved. The material showed the selective adsorption of gadolinium ions using the carboxylate active sites provided by carboxymethylation and the microporous or mesoporous structures formed after carbon burning. The successful synthesis of the material was demonstrated by relevant characterization, and the results of static adsorption experiments showed that the material was more consistent with the quasi second-order kinetic model at pH = 5.0. The maximum adsorption capacity was 99.65 mg g-1. The material showed a high adsorption capacity for gadolinium ions in the presence of competing ions and maintained 84.07% of the adsorption performance after five adsorption cycles. The simple use of urea ensured that the cellulose maintained its pore structure, and the specific surface area was greatly increased after carbonization, which provided a feasible direction for the industrial adsorption and recycling of rare-earth elements for reuse.

Study on the combustion characteristics and kinetics of water hyacinth co-combustion with anthracite

Water hyacinth(WH) is a promising resource produced as a by-product of treating pollution in watersheds, but little study has been done on its high-value applications. In this work, the combustion characteristics of WH, anthracite (AN), and their blends under different ratios, and heating rates were investigated by the thermogravimetric (TG) analyzer. The Kissen-Akahira-Sunose (KAS) and Flynn-WallOzawa (FWO) methods are used to calculate the dynamics, and the interaction between the mixed materials is discussed. The results show that the combustion characteristics of WH are better than those of AN because of its higher volatile components. With the increase of WH, the comprehensive combustion index increased from 0.15(pure AN) to 2.22(WH: AN=5:5). With the increase in heating rate, there is no significant difference in residual. The difference in thermogravimetric curves of mixed fuel in the volatile combustion stage and fixed carbon combustion stage shows that there is an interaction between WH and AN in the process of co-combustion, indicating that the mixed fuel is suitable for co-combustion. This study provides a theoretical basis for improving the efficiency of clean energy and reducing the consumption of fossil energy.

Design and energy, exergy, and exergoeconomic analyses of a novel biomass-based green hydrogen and power generation system integrated with carbon capture and power-to-gas

The conversion of thermal energy into electrical power through combustion in combined cycle power plants is a prevalent method of energy conversion. Sustainable energy management requires effective energy storage, and power-to-gas (P2G) technology is a recent solution to this problem. In this research work, a novel biomass-based power plant is proposed, this specific type of biomass is composed of industrial wood chips and wheat straw chopped wood with a 3.48:1 mass ratio and 19 wt% moisture. Detailed energy, exergy, and exergoeconomic analyses are performed for each component, considering various ambient and system conditions. This power plant is also equipped with a carbon capture and storage system, by which combustion's carbon dioxide is separated, and a power-to-gas energy storage system, by which hydrogen and oxygen gases are produced, allowing it to produce synthetic natural gas by the methanation process with various industrial applications and reduce carbon emissions. The energy and exergy analyses show that the overall energy efficiency and exergetic efficiency of the plant are 56.49 % and 35.48 %, respectively, which are highly acceptable and feasible. The combustion chamber is the primary location of exergy destruction, accounting for 52 % of the total exergy destruction in the cycles, followed by the methanation unit (15 %) and the turbine (12 %). Furthermore, the effect of modified ambient and manual operational parameters on the overall performance of the plant is analyzed, increasing the gas turbine inlet temperature improves the plant's energy efficiency to 57 %; but leads to a negative impact on its exergy efficiency (32 %), which manufacturing barriers make it difficult to increase beyond 1600 °C. Building the plant in a warmer geographic location barely impacts the energy efficiency; however, it may cause a decline as high as 1 % in the exergy efficiency.

Thermogravimetric Assessment and Differential Thermal Analysis of Blended Fuels of Coal, Biomass and Oil Sludge

The coupled combustion of biomass and organic solid wastes including oil sludge has attracted much attention. Although the optimal mixing ratio of different coal types and biomass has been extensively studied, little attention has been paid to oil sludge that has undergone co-combustion. In this study, the combustion characteristics of blended fuel for coal, biomass and oil sludge under different mixing ratios are studied via a thermogravimetric test and differential thermal analysis. Kinetic analysis of tri-fuel is performed using the Flynn–Wall–Ozawa (FWO) and Dolye methods. The results show that the bituminous coal combustion process mainly involves the combustion of fixed carbon (236.0–382.0 °C). Wood pellet combustion (383.0–610.0 °C) has two processes involving the combustion of compound carbon and fixed carbon. Blending wood pellets effectively enhances combustion efficiency. Wood pellets from Korla (KOL) have the most obvious effect on reducing the ignition temperature. The blending combustion of bituminous coal (SC), wood pellets from Hutubi (HTB) and oil sludge (OS) have significant synergistic effects. As the OS mixing ratio increases from 10% to 20% with 45% HTB, Ti and Th decrease from 354.9 and 514.3 °C to 269.8 and 452.7 °C, respectively. In addition, f(α) is [−ln(1 − α)]2 for tri-fuel in most mixing ratios when α < 0.5, while f(α) becomes [−ln(1 − α)]3 at α > 0.5. At a high-HTB-level mixing ratio, increasing the OS content causes a decrease in activation energy to 35.87 kJ mol−1. The moderate blending of oil sludge improves the pre-finger factor and the combustion performance.