Incorporation of biomass-derived materials in coal blends for cokemaking is one of the strategies that could reduce the levels of greenhouse gas emissions produced by the steelmaking process. Bio-coke refers to the resultant coke prepared with the addition of charcoal to a coal blend. In this work, characteristics of bio-coke gasification by reacting with CO2 were examined using Thermal Gravimetric Analysis. Bio-coke samples with different levels of charcoal addition to a coal blend were prepared in the CanmetENERGY pilot-scale coke oven. These samples were heated in CO2 for identification of the minimum gasification temperature. Sample gasification rates at 1000 °C were also measured. It was observed that mineral content plays an important role in the gasification characteristics of the bio-cokes. Those with low mineral content behave very similarly to the reference coke. Higher mineral content bio-coke reacts with CO2 at a lower temperature. It was found that the gasification characteristics of the bio-cokes are well described by the alkalinity index.

Processes involving biomass oxidation are considered to be CO2 neutral since the replenishing of the biomass by normal growth will remove CO2 from the atmosphere. Thus the use of charcoal in the production of metallurgical coke, to be used as a reducing agent in the formation of iron, would be a strategy for the reduction of CO2 in the overall ironmaking process. This paper describes experimental attempts to produce industrial grade coke from coking coal blends to which are added amounts of charcoal up to 10%. Coking experiments were carried out partly in a 30 lb coke oven and partly in a sole heated oven. The influence of blend composition, heating rates and charcoal particle size was investigated. Cokes made using fine charcoal addition (-60 mesh) were considerably weaker than cokes made from the base blend. This is interpreted to be the effect of the ash constituents in the charcoal which, among other things, contains much higher calcium than the coals used. However, carefully sized fractions of coarse charcoal (-3/8 + 1/4 in) produced much higher quality coke, possibly the result of a different dispersion of the charcoal mineral components. Crown Copyright (C) 2008 Published by Elsevier B.V. All rights reserved.

A Victorian lignite, designated Loy Yang low ash, run of mine (LYLA (R)) has been dewatered using mechanical thermal expression (MTE) at 150–200°C and 6–25MPa and by hydrothermal dewatering (HTD) at 200–300°C and the products compared. Total acidity values for all samples as measured by a pyrolysis thermogravimetric Fourier transform infrared (TG–FTIR) method were similar to those measured by barium ion exchange. Stronger (carboxylic) acid values determined by pyrolysis TG–FTIR tended to be lower than ion exchange values, except for the 300°C HTD sample, for which both methods gave similar values although these were much lower than at all of the other treatment temperatures. Equilibrium moisture contents (EMC) for the MTE products and the 200°C HTD product were similar to those of the original lignite at relative vapour pressure (RVP) ⩽52%, but lower at RVP 92%. EMC values for 300°C HTD products were all lower than for the original lignite, indicating that processing temperature was the most important factor in determining these properties. CO2 adsorption surface area was also mainly a function of processing temperature, decreasing with increasing temperature. However, the pore volume as determined by mercury porosimetry was influenced by whether dewatering was effected by MTE or HTD, the mechanical pressure applied in the MTE process resulting in a lower porosity.

This paper attempts to relate oxygen- containing gases H2O, CO2, and CO evolved during pyrolysis of the Argonne premium coals to oxygen- containing functional groups as a function of rank. Our approach to functional group analysis of oxygen- containing species in coal has been to use a pyrolysis technique, thermogravimetric Fourier transform infrared spectroscopy ( TG- FTIR), involving thermogravimetric analysis with the measurement of the gaseous decomposition products via IR detection. Under suitable heating conditions, TG- FTIR pyrolysis of a coal sample in a stream of inert gas has been shown to expel quantitatively all of the organic oxygen in the form of H2O, CO2, and CO, and consequently, this technique can be effectively applied for determining the total oxygen content. Focusing on the Argonne premium coals, which cover a wide range in rank between lignite ( Ro = 0.25) and low- volatile bituminous ( Ro = 1.68), TG- FTIR provided complex pyrolysis profiles of oxygen- containing gases, which yield information on the sources of the different peaks observed in coal as a function of rank from a chemical- structure standpoint. Deconvolution of the complex profiles was performed to assign peaks to the different sources of oxygen- containing gases. Model polymers containing various oxygen functional groups in aliphatic and/ or aromatic molecular environments were also pyrolyzed by TG- FTIR in an attempt to assign peaks in the gas evolution profiles of the Argonne premium coals. Although complex evolution profiles were observed for the three oxygen- containing gas species H2O, CO2, and CO in the Argonne premium coals, the strength of the TG- FTIR technique in revealing both similarities and differences in profiles depending upon the coal rank was evident. The findings in this investigation are compared to data published on oxygen functional group analysis for the Argonne premium coals made with various analytical techniques.

During rapid pyrolysis of coal, TG-FTIR (thermogravimetry - Fourier transform infrared) technique can be effectively used to simultaneously detect and measure the three main O-containing gases, namely H2O, CO and CO2. Their sum corresponds to the quantitative amount of oxygen in the coal and is, in general, inherently more accurate than the 'by-difference' values.In this paper, we first attempt to relate the 'by-difference' values for %O reported for the Argonne premium coal samples (lignite to bituminous rank) (Argonne Users Handbook) to those determined from a TG-FTIR examination of the pyrolysis gases evolved. Another objective of the work is to relate the pyrolysis gases (H2O, CO and CO2) evolved to oxygen-containing functional groups found in coals as well as the evolution of these functional groups as a function of rank. Correlations are also developed between the TG-FTIR oxygen values and other parameters determined for the Argonne Premium Coals. In particular, comparisons of our results using TG-FTIR with analyses carried out by other workers on functional group analysis of acidic groups are considered. (c) 2005 Elsevier B.V. All rights reserved.

Thermogravimetric-Fourier transform infrared (TG-FTIR) studies, using a ramp rate of 30°C/min, have been used to determine the total acidity and carboxylic acid contents for a range of lignites from the Latrobe Valley coal fields, Vic., Australia, some of which were also studied in water- and acid-washed form. The results are compared with values determined by barium ion-exchange. Total acidities from barium ion-exchange showed good agreement with those determined from the total amount of CO+CO2 evolved. The carboxylic acid content determined from the amount of CO2 evolved in pyrolysis showed a good correlation with the concentration of stronger acid functional groups determined by barium ion-exchange, but was lower. The effect of ion-exchange with Na, Mg, Ca and Al on CO, CO2, pyrolysis H2O and hydrocarbon gas production, as well as on the relative yields of these different gases, was similar to that observed by earlier workers for pyrolysis over much longer run times.

Motor vehicle (MV) emissions and ambient particle concentrations under a variety of situations were studied in Toronto and Vancouver, Canada. Petroleum biomarkers (i.e., hopanes and steranes) were used to determine the fraction of fine particle organic carbon (OC) attributed to primary particles in MV exhaust. Source profiles obtained from a tunnel and from direct tailpipe emissions were applied to ambient measurements at locations ranging from rush hour traffic to a regional background site. The greatest amount of MV OC, 4.0μgCm−3 out of 9.1μgCm−3 or 43%, was observed 75m south of a commuter highway during a period that included morning rush hour. Monthly estimates of MV-OC were determined for a downtown Toronto monitoring site for 2 years. Total OC concentrations were greater in the summer, due to secondary OC, but the amount of MV-OC did not exhibit a strong seasonal pattern. However, on a per cent basis, MV contributions from primary OC emissions were greatest in the winter (15–20%) and smallest in the summer (10–15%) with a two-year average of 14% of the OC or about 5% of the PM2.5.

The natural oxidation/weathering of coal continues to be a subject of interest both scientifically and industrially, in part due to the complexity of the molecular processes at hand as well as to the commercial implications involved. It is widely recognized that coking can be adversely affected by weathering whereas, combustion processes appear to be enhanced as result of oxidation.Combustion techniques are commonly used in the analysis of coal, and organic compounds in general, for the determination of elemental hydrogen, carbon and nitrogen. For oxygen, the method in common practice involves the determination by difference from directly determined values for moisture, ash, sulphur, hydrogen, carbon and nitrogen. This has led us to consider the use of thermogravimetry coupled to gas analysis by infrared spectroscopy (TG-FTIR) to measure organic oxygen in coal directly. Although this technique, developed by Solomon and coworkers, has been extensively used by our group and others, it appears not to have been considered for this particular purpose.Recently, we have shown that TG-FTIR is capable of measuring all the organic oxygen in both fresh and oxidized coal by simultaneous measurement of the three main oxygen-containing gases H2O, CO and CO2 evolved during rapid pyrolysis. This gives us a way of measuring quantitatively the oxygen introduced into the coal matrix during oxidation and at least a partial capability of establishing oxygen speciation.We have found, using TG-FTIR, that the early stages of coal oxidation results in the appearance of O-containing functional groups not present in the original coal. The nature of these functional groups is directly related to the oxidation reaction mechanism. These results will be presented and discussed in detail. Crown Copyright (C) 2004 Published by Elsevier Ltd. All rights reserved.

Thermogravimetry with Fourier Transform Infrared Analysis (TG-FTIR) has been used to measure the organic oxygen content in a suite of coals of differing rank and compare these with the values determined by difference according to ASTM D3176-89. Two coking coals, one Cretaceous and one Carboniferous, were oxidized at 50 °C to simulate natural weathering and analyzed for their oxygen content by both techniques. Results indicate that the pyrolysis technique is reliable and rapid and is free of the large possible errors inherent in the determination of organic oxygen content by difference.

In this work, we have subjected two bituminous coals of similar rank and dissimilar geological origin to natural oxidation and analyzed the resulting samples using TG-FTIR. The results clearly reveal a first oxidation step lasting 2-4 weeks followed by a slower reaction that continues indefinitely. Data on the evolution of CO, CO2 and H2O indicate that the oxidation mechanisms are different - the first step resulting in the evolution of CO and CO2 with the second step involving the evolution of H2O.TG-FTIR was found to be a sensitive technique for detecting low levels of natural oxidation when more conventional methods are insufficient.

The CANMET Energy Technology Centre (CETC), in cooperation with the Department of Energy of the Province of Alberta and the Canadian Carbonization Research Association (CCRA), has completed a program on the evaluation of Canadian and foreign coals for blast furnace injection. The program consisted of two parts: (1) theoretical assessment of cooling and coke replacement characteristics of coals using CETC`s computer model and (2) experimental determination of the combustibility of coals of different ranks and particle size as well as the influence of oxygen enrichment on burnout. The experimental part was conducted in a pilot-scale injection unit designed and built at CANMET that simulates blast furnace blowpipe-tuyere conditions. This paper describes the facility and methodology of work. It also discusses results. The prime objectives of this study were to provide essential information on coal combustion in the blast furnace and establish proper criteria for evaluating and selecting coals for blast furnace injection.

CANMET Energy Technology Centre (CETC) has been involved in a research program to evaluate the suitability of various coals for blast furnace injection. The primary objectives of this program are to provide essential information on coal combustion in the blast furnace and to establish proper criteria for evaluating and selecting coals for blast furnace injection. The program comprises three parts. Parts one and two have been completed. To date, the program has encompassed both a theoretical assessment of cooling and coke replacement characteristics of coals using CETC`s computer model and an experimental determination of the combustibility of coals of different ranks and particle sizes as well as the influence of oxygen enrichment on burnout. The experimental part was conducted in CETC`s pilot-scale injection unit that simulates blast furnace blowpipe-tuyere conditions. Part three now being developed will incorporate results of experimental trials into a blast furnace raceway model in order to predict total combustibility of coals at different blast furnace operating conditions. This paper describes CETC`s facility and methodology of work, and presents and discusses results.

Neutral and acidic fractions of cold lake bitumen asphaltene were separated on a KOH treated silica column. It was observed that the neutral fraction can be separated by using CHCl3 as solvent (eluent) while the acidic fraction can be separated by a CHCl3 + HCOOH mixture. While the distribution of VO2+ ion was approximately the same in the different fractions, the concentration of the radicals may be significantly more in the acidic fraction. The acidic fraction separated has the largest impact on decreasing the interfacial tension (IFT) between asphaltene (in toluene) and 25mM NaOH solution. It was also observed that adsorbed KOH on silica reacted with CHCl3 when the CHCl3 + HCOOH mixture was passed through the column.

A novel loose-pack dilatation (LPD) method for coal dilatatometry is described and validated. It uses slightly modified Ruhr or Audibert-Arnu apparatus. The test sample consists of a weighed amount of coal which is directly transferred into the retort tube. Requirements of ISO methods associated with using pulverized coal to prepare pencil are eliminated, so the LPD method is easier and more versatile, allowing coals and blends to be tested which are closer in particle size and composition to those used in industrial processes. Softening temperatures are determined by the penetration of a pin into the coal under a 375 g piston assembly. Expansion of the LPD test sample under this load is closer to conditions in coke ovens. It is possible to determine expansion, and assign a full melting range, to some coals which exhibit only contraction when tested by the Ruhr method.