Coal Blends Research Articles

Numerical Simulation Study of Hydrogen Blending Combustion in Swirl Pulverized Coal Burner

Hydrogen blending of pulverized coal in boilers is a promising technology. However, there are few studies on hydrogen blending in coal-fired boilers. In order to reduce CO2 emissions from coal-fired boilers, this study investigates the co-combustion of pulverized coal and hydrogen in a swirl pulverized coal burner by numerical simulation. Itis shown that the burnout rate of fuel is 5.08% higher than that of non-hydrogen blended coal when the percentage of hydrogen blended is 5%. The water vapor generated by hydrogen blending not only leads to the formation of a low-temperature zone near the burner outlet; it also results in a prolonged burnout time of moist pulverized coal and a high-temperature zone near the furnace outlet. The greater the amount of hydrogen for blending, the higher the water produced. When 1–3% hydrogen is blended, the water vapor in the furnace reacts with the carbon to produce a large amount of CO. When the amount of hydrogen added to the furnace is more than 3%, the water content in the furnace rises, resulting in a lower temperature at the burner outlet and a decrease in the amount of CO produced. When 1–3% hydrogen is blended, the CO2 emission rises. The CO2 emission decreased by 1.49% for 5% hydrogen blending compared to non-hydrogen blending and by 3.22% compared to 1% hydrogen blending.

INVESTIGATING RELATIONSHIPS BETWEEN INTRINSIC PROPERTIES, PREPARATION PARAMETERS OF COAL AND COKE QUALITY: A SYSTEMATIC LITERATURE REVIEW

The purpose of this study is to review some of the key research concepts related to metallurgical coke. As the research landscape for coke metallurgy is evolving, researchers are increasingly interested in the effects of the intrinsic properties of coal, coal preparation parameters, and the technological conditions of coke production on the quality of metallurgical coke. As part of this review, a specific protocol, content analysis and thematic coding of cases of the “Preferred Reporting Items for Systematic Review and Meta-Analyses” method were used to investigate the simultaneous effect of these two parameters on the quality of coke in selected journal articles. A review of 118 articles was conducted, including their abstract, introduction, methodology, and results. According to the results of this study, coal blends and coal particle sizes have a direct effect on the three sections of coke mechanical properties, coke texture, and coke reactive properties. Reviewing various articles has shown that the presence of fatty coals in smaller size distribution, combined with largersized weak coals, leads to the formation of a stronger structure in the produced coke. However, this does not guarantee an improvement in the coke reactivity parameters. On the other hand, increasing the blending ratio of coking coals in the final mixture for producing normal-sized coke (dimensions smaller than 3 millimetres) improves the coke reactivity parameters. Studies investigating coke structure have demonstrated that a cohesive mosaic structure in high-quality cokes results from well-distributed maceral blends of coking coals with optimal size distribution among other coals.

Techno-economic assessment for metallurgical coals: a ‘value-in-use’ approach

The optimization of coke cost is the most significant cost-controlling factor for hot metal production. Therefore, worldwide cokemakers always have extra pressure from management to produce superior quality coke with inferior raw materials and optimal costs. Coke quality is crucial in blast furnace operation regarding cost and productivity. The quality of coke is significantly influenced by the quality of different categories, viz., prime hard coking coal, hard coking coal, soft coking coal and semi-soft coking coal of individual coals used in the coal blend. The impacts of these coals directly influence coke properties because all coals have an inherent characteristic with different coking potentials in terms of value-in-use (VIU). Also, the technological and techno-commercial change of the metallurgical coal market of today differs from past decades. Likewise, the future metallurgical coal market will vary from today’s market. Therefore, a process for assessing/evaluating the coking potential of metallurgical coal shall be used for appropriate value-in-use to produce quality coke with the optimum cost. The composite coking potential methodology served the value-in-use purpose and was successfully implemented. The paper describes the significance of the value-in-use of metallurgical coal to evaluate the most economically favourable technique for producing the desired coke quality.

Вплив добавок на показники якості коксу

DOI: 10.31081/1681-309X-2024-0-2-3-14 Specialty 161. U.D.C. 662.7:552.57 INFLUENCE OF ADDITIVES ON COKE QUALITY PARAMETERS © D.V. Miroshnychenko, Doctor of Technical Sciences, O.I. Zelenskii, Ph.D. in Technical Sciences (National Technical University "Kharkiv Polytechnic Institute", 2, Kyrpychova str., Kharkiv, 61002, Ukraine), O.L. Borysenko, Ph.D. in Technical Sciences, V.V. Koval, Ph.D. in Technical Sciences (State Enterprise “Ukrainian State Research Institute for Carbochemistry (UKHIN)”, 7 Vesnina str., Kharkiv, 61023, Ukraine), E.L. Solovyov (NTU “KhPI”), S.V. Pyshyev, Doctor of Technical Sciences (Lviv Polytechnic National University, 12, S. Bandera Str., Lviv, 79013, Ukraine) The article is devoted to the study of the possibility of identifying the influence of various additives on the quality of laboratory coke, including the electrical resistance of its structure. Inorganic powders of silicon and silicon carbide (carborundum), as well as an organic additive of petroleum coke, were used as charge modifiers. It is shown that the use of inorganic powder additives will be especially relevant for coal charges with poor coking properties. The obtained results show that the introduction of non-sintering inorganic additives in the amount of 0.125 to 0.5 % by weight allows regulating the processes in the plastic state in order to increase the strength of coke. In particular, the addition of SiC leads to a significant increase in the hot strength index (CSR) and a decrease in the reactivity index (CRI). The improvement of these coke parameters using SiC additives was confirmed by the analysis of other physical and chemical properties of coke. The specific effect of such a modification on coke quality depends on the grade composition of the coal charge. The data presented in the article indicate an increase in the degree of orderliness of the coke structure and the appearance of a larger number of nanostructures when petroleum coke additive is introduced into coal blends in the amount of 5 % by weight. Such modification of the charge also leads to an increase in the yield of gross coke by 1.2-1.3 %; an increase in the total sulphur content in coke by 0.15-0.23 %; a decrease in the ash content of coke by 0.2-0.3 %; deterioration of mechanical strength (P25 – оby 0.1-0.6 %; I10 - by 0.1-0.2 %) and coke strength after reaction (CSR – by 0.6-1.0 %), coke reactivity (CRI – by 0.2-0.3 %), as well as structural strength (SS – by 0.3-0.4 %), abrasive hardness (AH – by 0.7-1.0 mg) and resistivity (ρ – by 0.002-0.007 Ohm×cm). Due to the positive impact of Svyato-Varvarinskaya coal on the quality of blast furnace coke, the quality of coke produced with a higher share of this coal in the charge is improving. On the other hand, when using a coal charge characterised by the lowest content of the aforementioned coal, the quality of the coke produced is rapidly decreasing. Keywords: coal charge, blast furnace coke, quality, modification, additives, petroleum coke, silicon carbide. Corresponding author O.L. Borysenko, e-mail: zd@ukhin.org.ua

Розробка оптимальних складів вугільних шихт для трамбування. Повідомлення 2. Дослідження вугільних шихт з оцінкою якості одержаного коксу

The article describes the results of the study of the developed coal blends (charges) in the form of calculations and laboratory analyses. Their tamping ability was also studied to determine the shearing force and density of the coal cake at different levels of moisture and grinding. The values of the bursting pressure of the developed coal blends were determined. It is shown that all of them are characterised by safe values of this indicator for coking. It is determined that the greatest influence on the value of the bursting pressure of the charge is exerted by the content of class <0.5 mm. The points of extremum (optimum) of the bursting pressure function obtained by differentiating the second-degree regression equation, in which the first-order derivative is zero, are given. The optimum range of coal charge moisture content, at which the tamping characteristics reach their maximum values, has been determined. It is shown that with a decrease in the yield of volatile substances, the value of tamping shifts to the upper limit, and vice versa. It was found that the charge with the highest amount of finely dispersed additives has the best tamping ability. Laboratory coking of the developed coal blends was carried out to evaluate the quality characteristics of the resulting cokes, the analysis of which allowed us to select the optimal compositions of coal blends. The cokes obtained from the blends characterised by the highest values of the tamping index were the best in terms of mechanical strength. It has been established that in terms of reactivity (CRI) and coke residue strength after reaction (CSR), all variants of the obtained coke have quite satisfactory values, given the unfavourable ratios of basic and acidic oxides in the chemical composition of ash. The paper presents and substantiates the calculation of the optimal height of coking chambers. Based on the obtained values of the strength of tamped briquettes σzz from the studied compositions, the height of the coking chambers should be 5.5 m. At the same time, the tamping ratio (cake height to its width) should be no more than 13. Keywords: tamping, coal cake, shear resistance, strength of the tamped cake, coke quality, height of the coking chamber. Corresponding author Miroshnichenko D.V, e-mail: dvmir79@gmail.com

Co-combustion characteristics and kinetics of sludge/coal blends in 21%–50% oxygen-enriched O2/CO2 atmospheres

This research investigated the thermogravimetric analysis (TGA) and combustion kinetics of sewage sludge and Australian sub-bituminous coal and their blends with different mixing ratios (sludge/coal = 100/0, 80/20, 50/50, 20/80, 0/100 by weight) under air atmosphere (O2/N2 = 21/79 by volume), oxy-fuel combustion (O2/CO2 = 21/79, 25/75, 35/65, and 50/50 by volume), and pyrolysis (pure N2 atmospheres). The gaseous products that evolved from the TGA experiments were also analyzed using a Fourier transform infrared (FTIR) spectrometer under pyrolysis conditions. Results showed that the mixed fuel with higher coal blending ratio had higher ignition temperature, lower burnout temperature and larger combustion characteristic index. Furthermore, TGA–FTIR experiments of the 20 % sludge + 80 % coal blended fuel under nitrogen atmospheres showed more gasification components in pure coal than in sludge. The combustion kinetics analytical results via the Flynn–Wall–Ozawa method indicated that the larger the conversion degree, the smaller the obtained activation energy value. Under the oxy-fuel combustion conditions, when the oxygen concentration increased from 21 % to 50 % for the 20 % sludge + 80 % coal blended fuel, the ignition and burnout temperatures decreased, and the combustion characteristic index increased nearly three times. Oxygen enrichment can clearly improve combustion characteristics and flammability.

Coal blending optimization in thermal power plants based on multi-strategy fusion multi-objective particle swarm optimization

ABSTRACT Rising coal price and increasingly stringent emission policy highlight the importance of balancing economic benefit and sustainable development of coal-fired power plants. In order to make the power plant operate economically and safely, and reduce the emission of pollutants as much as possible, this paper proposed a coal blending optimization framework for coal-fired power plants. This framework constructs a set of mathematical model based on the minimization objective function, including the economy, safety and environmental protection of coal. And a multi-strategy fusion multi-objective particle swarm optimization (MSF-MOPSO) method is proposed to optimize the coal blending model. The feasibility, effectiveness and superiority of the method are theoretically verified by convergence analysis and several sets of simulation experiments. And the practical application of this framework shows that under the coal blending strategy based on different weight combinations, the algorithm proposed in this paper can produce high-quality Pareto spatial distribution. Comparing with other state-of-the-art coal blending algorithms, this method can reduce the coal purchase cost by 4.42% and S O 2 emission by 5.11% at least under the same condition. It has significant environmental protection and economic benefit.

Research on the adsorption mechanism of As by Fe-bearing minerals in coal during high-temperature combustion

As can be retained by Fe components in coal during high-temperature combustion, which is beneficial for reducing As emissions. In this study, high-temperature As adsorption experiments were carried out in a fixed-bed experimental system with As model compound and minerals. The adsorption amount of As was much higher when Fe2O3, SiO2, and Al2O3 acted together than when they acted alone. As was mainly distributed in the Fe-Si-Al minerals generated by the reaction of the three oxides, for which the Fe2O3:SiO2:Al2O3 mass ratio of 1:1:1 was the most favorable, and the maximum adsorption amount of As was 18.2 mg·g−1. Density functional theory calculations were carried out for the adsorption of As2O3 by Fe2O3, SiO2, Al2O3, and Fe2Al4Si5O18. Fe2Al4Si5O18 had the highest adsorption energy for As2O3, indicating the most stable adsorption. As2O3 was adsorbed on the Fe and Si sites. The adsorption ability of the Fe site was strengthened in Fe2Al4Si5O18 relative to that in Fe2O3. The formation of Fe-O-Si and Fe-O-Al in the mineral promoted electron transfer from the adsorbent to As2O3 molecule, thereby strengthening adsorption. These results can guide the optimization of coal blending methods and the modification of adsorbents to control As emissions in coal-fired systems.

Machine learning prediction of pyrolytic sulfur migration based on coal compositions

Understanding the sulfur migration during pyrolysis of coals especially high-sulfur coals is important. However, structural complexity and diversity of coals make it face huge challenge. In this study, a predictive model for morphological sulfur migration was developed using machine learning based on proximate analysis, ultimate analysis, sulfur forms of raw coal, ash composition, and blending ratio of coal. Three algorithms, i.e., Random Forest, XGBoost, and LightGBM were introduced and compared. The results show that six features are sufficient to accurately predict the products (R2 > 0.9, RMSE < 3.01%). LightGBM model has the advantages of better accuracy, generalization, efficiency, and performance, and Hyperopt has a higher upper limit than Grid-search. H content has a significant effect on S content in chars (St,dchar) and increasing H content from 5.0–5.3 wt% facilitates desulfurization. In addition, CaO, K2O and Fe2O3 also have remarkable effects on St,dchar. Higher H and volatile contents have a greater effect on thiophene removal in char. This work can provide a new approach to explore the sulfur migration in coal blending for coking.

Effect of vane angle on turbulence-chemistry interactions, temperature, flow field, burnout, and NOx emissions in swirling flames fueled by semicoke mixtures.

To enhance the combustion efficiency and reduce NOx emissions in large-scale semicoke and bituminous coal blends, an extensive numerical study was conducted. The focus of this study was to optimize the quaternary air vane angle (αv) through detailed analysis of the temperature and flow fields, turbulence-chemistry interactions, char burnout, and NOx formation in a carefully scaled 1:5 dual-swirl burner. The results showed that with increasing αv, the high-temperature flame region was narrowed and the peak temperature was reduced along with the broadened inner recirculation zone and the shrunken external recirculation zone due to better pulverized fuel-oxidant blending and reinforced convective heat transfer. The peak turbulent Damköhler number Dat evidently increased from 197.5 to 496 with increasing αv, which implied a strengthened homogeneous combustion. Additionally, the corresponding mixing time scales increased while the chemical kinetics time scales decreased, which denoted that an intense diffusing flame was generated with a strong turbulent intensity. The peak heterogeneous Damköhler number Das-O2 showed a reduction from 2.54 to 2.27, while the peak values of Das-CO2 and Das-H2O decreased from 0.1 to 0.077 and from 0.02 to 0.015, respectively. The char-O2 reaction was controlled by diffusion/kinetics; both char-CO2 and char-H2O reactions were determined by kinetics, and all gas‒solid reactions showed a kinetically controlled regime. With increasing αv, the enlarged inner recirculation region increased the residence time, and a higher dilution level lessened the peak temperature, which led to reductions in fuel-NOx and the thermal-NOx. The αv range of 30-45° (or swirl number Sn = 0.55-0.95) was suggested by taking the high burnout and low-NOx formation into account.

Modeling of arsenic migration and emission characteristics in coal-fired power plants

After coal combustion, the minerals present in fly ash can adsorb arsenic (As) during flue gas cooling and reduce As emissions. However, a quantitative description of this adsorption behavior is lacking. Herein, the As adsorption characteristics of minerals (Al/Ca/Fe/K/Mg/Na/Si) were investigated, and a model was developed to predict As content in fly ash. Lab-scale experiments and density functional theory calculations were performed to obtain mineral As adsorption potential. Then, the model was established using lab-scale experimental data for 11 individual coals. The model was validated using lab-scale data from ten blended coals and demonstrated acceptable performance, with prediction errors of 2.83–11.45 %. The model was applied to a 350 MW coal-fired power plant (CFPP) with five blended coals, and As concentration in the flue gas was predicted from a mass balance perspective. The experimental and predicted As contents in fly ash were 11.92–16.15 and 9.61–12.55 μg/g, respectively, with a prediction error of 17.39–22.29 %, and those in flue gas were 11.52–16.58 and 5.37–34.04 μg/Nm3. Finally, As distribution in the CFPP was explored: 0.74–1.51 % in bottom ash, 74.05–82.70 % in electrostatic precipitator ash, 0.53–1.19 % in wet flue gas desulfurization liquid, and 0.13–0.73 % in flue gas at the stack inlet.

Ash fusion behavior modification mechanisms of high-calcium coal by coal blending and its ash viscosity predication

In this paper, the ash fusion temperature (AFT) modification of high calcium Huolinhe lignite (HLH) with the addition of high aluminum Datong coal (DTC) and their corresponding mechanisms were investigated by an AFT tester, X-ray diffractometer, Raman spectrometer, and FactSage software. The AFTs of HLH mixtures increased gradually with the increasing DTC mass ratio due to their corresponding decrease in the total basic oxide content of CaO, MgO, Fe2O3, Na2O, and K2O. The formations and content increases of high melting-point minerals (anorthite, cordierite, and mullite), the gradual decrease in the ratios of no bridging-oxide bond/bridging-oxide bond (NBO/BO), and an increase in the R (R = (Q3 + Q2)/(Q1 + Q0)) value resulted in the increases in the AFT and ash viscosity. Considering the variations in the characteristics of AFT and ash viscosity, the 40.0–50.0 % DTC mass ratio might be suitable for HLH entrained-flow bed (EFB) gasification. The combination of AFT measurement and ash viscosity predication using FactSage provided a simple method to determine whether ash characteristics of coal were suitable for EFB gasification.

Thermochemical Characterization and Kinetics of Biomass, Municipal Plastic Waste, and Coal Blends and Their Potential for Energy Generation via Gasification

Thermochemical Characterization and Kinetics of Biomass, Municipal Plastic Waste, and Coal Blends and Their Potential for Energy Generation via Gasification

Synergistic reduction of SO2 emissions while co-firing biomass with coal in pilot-scale (1.5 MWth) and full-scale (471 MWe) combustors

The objective of this study was to understand the synergistic effect of sulfur dioxide (SO2) emission reduction during the combustion of biomass-coal blends in comparison to pure coal by recording the gaseous SO2 concentrations, analyzing the composition of combustion ash by energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD), and simulating and verifying the fate of sulfur by a thermodynamic equilibrium software (FactSage). In Set A experiments, five combinations of coal and steam-exploded biomass (100/0, 75/25, 50/50, 25/75, 0/100 in percentages by mass) were co-fired in a 1.5 MWth pilot-scale combustor. In Set B, pure coal (100/0) and an 85/15 percent mass blend of coal and torrefied biomass were co-fired in a 471 MWe utility boiler. Woody biomass contains lower amounts of sulfur compared to coal and the linear lowering of SO2 emissions as a result of co-firing is called the dilution effect. For Set A tests, FactSage predicted, and ash analysis confirmed that calcium was primarily responsible for the synergistic emission reduction (beyond dilution effect) in all the blends, except in pure biomass, where potassium was responsible. During pure coal combustion, 41.1% of the sulfur in the system was absorbed in the ash, compared to 97.0% during pure biomass testing. In Set B tests, the 85/15 coal-biomass blend, showed a 28.1% reduction in SO2 emissions along with a 22.1% reduction in the lime slurry utilization at flue gas desulfurization (FGD) towers compared to pure coal, which is equivalent to saving 7.4 L of lime slurry per MWe-hour. The results suggest that blending woody biomass with coal can help coal-fired utility boilers meet environmental emission standards and reduce desulfurization costs. These results are important since the current literature is deficient in research conducted at suspension-fired full-scale boilers to reduce SO2 emissions by co-firing coal and biomass blends.

Exploring copyrolysis characteristics and thermokinetics of peach stone and bituminous coal blends

AbstractCopyrolysis, being an active area of research due to its synergistic impact in utilizing diverse fuel resources, including waste materials, like, peach stone (PS), has been the focal point for this study. PS, produced in vast quantities annually and typically intended for landscaping or insulation purposes, is being studied in combination with low‐grade bituminous coal for energy utilization focusing on thermokinetics and synergistic aspects. Coal‐peach stone (C‐PS) blends were formulated at different ratios and subjected to comprehensive characterization techniques, including ultimate analysis (CHN‐S), gross calorific value (GCV), Fourier transform infrared spectroscopy, and thermogravimetric analyzer (TGA). The ultimate analysis revealed an enhancement in carbon and hydrogen content from 45.38% to 68.08% and from 3.89% to 6.96%, respectively. Additionally, a reduction in sulfur and nitrogen content from 0.54% to 0.11% and from 1.16% to 0.42%, respectively, was observed with an increase in the ratio of PS in the C‐PS blends. The GCV of C‐PS blends ranged from 20.75 to 26.01 MJ kg−1. The pyrolysis conditions simulated in TGA are pivotal for evaluating thermokinetics and synergistic effects. The 60C:40PS blend shows a positive synergy index (SI) value of 0.0203% concerning total mass loss (MLT) indicating a favorable condition for bio‐oil generation. Coats–Redfern model‐fitting method reveals that the activation energy (Ea) of C‐PS blends increases in Section II with the addition of PS, and conversely, it decreases in Section III. The Ea for 100PS and 100C was 106.76 and 45.85 kJ mol−1 through (D3) and (F1), respectively, which was improved through the optimal blend 60C:40PS with an Ea of 94.56 and 27.58 kJ mol−1 through (D3) and (F2), respectively. The values obtained from linear regression prove that the kinetic models are effective while the thermodynamic analysis indicates that the pyrolytic behavior of C‐PS blends is characterized as endothermic, nonspontaneous, and capable of achieving thermodynamic equilibrium more rapidly.

Muti-objective optimization on energy consumption, CO2 emission and production cost for iron and steel industry

Due to high material density, high energy consumption density and CO2 emission density, it is not only difficult but significant to clarify the relationship between energy consumption, the CO2 emission and the production cost in different conditions. However, the previous researches rarely refer how to balance the energy consumption, the CO2 emission and the production cost after the fluctuation of material, energy and carbon price as well as what will happen to them if production structure changes. Therefore, based on the conservation law of mass and energy, to study iron and steel manufacturing process (ISMP), this paper, taking carbon price into consideration, establishes a muti-optimization model of energy consumption, CO2 emission and cost. After optimization with different objectives, the production cost per tonne of crude steel is reduced by 192.03 CNY (7.71%), the CO2 emission per tonne of crude steel is reduced by 224.22 kg (13.37%), and the energy consumption per tonne of steel is reduced by 51.20 kgce (9.10%). Moreover, based on the optimization results under different objectives, it is ironmaking process (coal ratio and ore ratio) and steelmaking process (amount of scrap steel) that has more impact on three above as well as ore blending and coal blending have a great influence on production cost but little effect on energy consumption and CO2 emission.

Air distribution and coal blending optimization to reduce slagging on coal-fired boiler water wall based on POD reduced order modeling for CFD

Slagging is a common phenomenon interfering with the safe and efficient operation of coal-fired boilers. Due to the lack of monitoring methods for species and temperature distribution near the water wall, which is critical for slagging formation, it is a tricky problem to detect and reduce the slagging in real time. A method for slagging distribution prediction and anti-slagging optimization of a 330 MW tangentially coal-fired boiler is developed in this paper. Proper orthogonal decomposition (POD) reduced order modeling and support vector machine (SVM) are used to predict the distribution of temperature and O2 near the water wall by taking 15 variables as input parameters (load, coal types, primary air rate, secondary air rate, excess air coefficient, and secondary air velocities). Next, fuzzy comprehensive evaluation (FCE) is employed to quantify the slagging occurrence and distribution on the water wall. Furthermore, the real time slagging prediction is realized with the combination of POD, SVM, and FCE. Finally, the conventional genetic algorithm (CGA) and simulated annealing genetic algorithm (SAGA) are adopted to optimize the air distribution schemes and coal blending schemes to reduce the slagging ratio, and their performances are compared. The results indicate that the predictions of temperature and O2 with POD show a good agreement with CFD simulations. In the optimization process, whether air distribution is optimized alone or both coal blending and air distribution are optimized simultaneously, the performance of SAGA is better than that of CGA. After optimizing the air distribution with SAGA, the slagging ratio of a typical operating condition with a load of 330 MW is reduced from 14.21% to 7.16%. The slagging ratio is further reduced to 5.36% after optimizing air distribution and coal blending schemes simultaneously. The proposed slagging prediction and optimization for anti-slagging opens a new perspective to alleviate slagging of water walls effectively.

Comparative study between coal tar pitch and lower polycyclic aromatic hydrocarbon (PAH) alternative binders for use in taphole clays

The use of alternative low polycyclic aromatic hydrocarbon (PAH) binders in taphole clays is essential due to health and environmental concerns associated with PAHs. Binders that could potentially substitute for highly-temperature coal tar pitch (CTPht) or coal tar (CTht) in taphole clays were investigated. These include coal tar pitch blend, low PAH coal tar pitch, petroleum-based binders and wood-based tars from various sources. The binders were characterized according to chemical composition, with an emphasis on the identification of 16-EPA-PAH (well-known carcinogens), as well as rheology and volatilization behaviour. The alternative binders were ranked according to the analytical results, with the coal tar reference binder, CTht, serving as the benchmark. Beechwood tar (Tar-BW) and crude waxy oil (CWO) showed the most favourable results for replacing CTht in taphole clay. Both have higher viscosities than CTht, lower BE-values (indicating lower toxicity), and higher degrees of mass loss over a wider temperature range.

Effective Utilization Method for Surface Tension Based Coal Blending Technique -Effect of Coal Fluidity-

Effective Utilization Method for Surface Tension Based Coal Blending Technique -Effect of Coal Fluidity-

Production of High-Strength Coke by Pressurization Carbonization of Modified-Biomass Blended Coal

Production of High-Strength Coke by Pressurization Carbonization of Modified-Biomass Blended Coal