Proximate volatile matter content

Analyses of Anthracites Used. For most of the experimental work an anthracite from the St. Nicholas breaker was used. Its proximate analysis (dry basis) was as follows C, 84.3% V.M., 4.5% ash, 11.2%. Anthracites from other breakers used in this program had the following volatile matter contents... 

Proximate analysis, determination of moisture content of the general analysis sample of coke Proximate analysis, determination of volatile matter content Proximate analysis, determination of ash content Determination of gross calorific value Ultimate analysis of coal and coke, determination of carbon and hydrogen content, high temperature combustion method Liebig method... 

The proximate analysis of coal was developed as a convenient and effective means for determining the distribution of products obtained by heating coal under a set of standard conditions. This particular group of tests has been used widely as the basis for coal characterization in connection with coal utilization. The proximate analysis (ASTM, 20111) of coal may also be considered as the determination of the general properties of coal and is, in reality, the determination of moisture content, volatile matter content, ash yield, and (by difference) fixed carbon yield in contrast to the ultimate analysis of coal which provides the elemental composition (Figure 8.5). 

For example, all of the carbon in coal is determined by ultimate analysis and it is not an indication (or determination) of the carbon-forming propensity (i.e., the coke-producing ability) of the coal as is the case with the test for the volatile matter content of coal. Thus, just as there has been the need to develop standard methods for the proximate analysis of coal, there has also been the necessity to develop standard methods for the ultimate analysis of coal. 

As in the case of coal, all determinations included in proximate analysis (moisture, ash, and volatile matter contents) are the subject of national and international standards (ISO 579 for the determination of total moisture content ISO 687 and ASTM D3173 for the determination of moisture in the analysis sample ISO 1171 and ASTM D3174 for the determination of ash ISO 562 and ASTM D3175 for the determination of volatile matter content). Table 6 summarizes typical coke chemical properties for some operating blast furnaces in Europe. 

The composition of coal is conveyed by representing its proximate and ultimate analysis. The former implies determination of contents of moisture, volatile matter, fixed carbon, and ash, while the latter implies total carbon, hydrogen, oxygen, nitrogen, sulfur and ash. Here, an account will be provided of the constituents of coal, moisture, volatile matter, ash, fixed carbon, and some miscellaneous components. 

Proximate and ultimate analyses results (Tables VII and VIII, respectively) show that fixed and total carbon content of the lithotypes decrease in the order vitrain, durain, and fusain. The reverse of this trend is found for percent ash content, vitrain having the least and the durains and fusains having the most. Durain was found to have the highest percentage of volatile matter vitrains have the highest percentage of sulfur. 

Proximate analysis Determination of the approximate overall composition (i.e., moisture, volatile matter, ash, and fixed carbon content)... 

The standard test method for proximate analysis (ASTM D-3172) covers the methods of analysis associated with the proximate analysis of coal and coke and is, in fact, a combination of the determination of each of three of the properties and calculation of a fourth. Moisture, volatile matter, and ash are all determined by subjecting the coal to prescribed temperature levels for prescribed time intervals. The losses of weight are, by stipulation, due to loss of moisture and, at the higher temperature, loss of volatile matter. The residue remaining after ignition at the final temperature is called ash. Fixed carbon is the difference of these three values summed and subtracted from 100. In low-volatile materials such as coke and anthracite coal, the fixed-carbon value equates approximately to the elemental carbon content of the sample. 

Correlate premaceral contents with corresponding proximate (fixed carbon, moisture, ash, volatile matter), ultimate (C, H, 0, N, S) and heating value (3TU) analyses. 

Taking into account the proximate analysis of the input material (water content W, volatile matter VM and ashes content A ), it is possible to estimate the fixed carbon Cf ... 

The material was a crushed using a forage harvester-crusher machine, and was then reduction by using a hammer mill. The following analytical tests were made for poplar characterization proximate analysis (Fixed carbon, volatile matter, ash content), ultimate analysis (C, H, N, S, O2, Cl), and heating value. 

Proximate analysis is often sufficient for meeting coking plant needs and consists of moisture, volatile matter, ash, fixed carbon, and (generally) sulfur. The sulfur content is provided as a part of the proximate analysis and is equivalent to the elemental sulfur determined in the ultimate analysis. 

Proximate analysis, which includes the moisture content, ash content, volatile matter, fixed carbon, and heating value (BTU/LB) of the waste... 

The proximate analysis of these samples was performed by using standard methods to measure the percentage of moisture (SABS 924, ISO 589), ash content (ISO II7I), and volatile matter (ISO 562). The difference between these three percentages and the mass of the original sample (100%) is referred to as the fixed carbon. The ash composition determination, in terms of its oxides, was conducted according to the ASTM D3682 standard. 

The elemental analysis of coal, i.e., its C, H, O, N, S, and ash residue, may be important to a chemist who wishes to use coal as a chemical or source of carbon, but to an engineer who wants to bum the coal in a heat- or power-generating plant or a coking oven, other parameters are more important— most notably its heat of combustion, moisture level, volatile matter, carbon and sulfur content, as well as the ash. This is called the proximate analysis and it is determined as follows ... 

The general position taken by researchers in the field is that the kinetics will mirror the parent coal—with some initial reaction suppression being caused by the water and ash content of the CWS [27]. At the same time reactivity measures can be calculated from the data presented previously in Tables 3.6 and 3.7. Such reactivity measures include volatile matter/fixed carbon (VM/FC) ratios from the proximate analysis, and atomic hydrogen/carbon (H/C) ratios and atomic oxygen/carbon (O/C) ratios from the ultimate analysis. Further, pollution measures can be calculated including kg S/GJ, kg SO2/GJ, kg N/GJ, and kg ash/GJ. 

The thermogravimetric analysis (TGA) can be also used as a standardless alternative to determine the proximate analysis within approximately 80 min. In TGA, a small coal sample (20 mg) is heated under a flow of nitrogen with 80K/min until 160 °C is reached and held on this temperature until all moisture is removed. An increase of the temperature to 950 °C removes the volatiles and after stabilization of the curve, air is finally introduced to convert the remaining fixed carbon. Relating to the original mass of the sample, the moisture, volatile matter, fixed carbon, and ash content are determined within the error limits of the standard method. 

The solid residue left after deducting the moisture—the volatile matter and the ash—is termed the fixed carbon. (It is to be noted that fixed carbon does not denote the total carbon content of the coal because some carbon is necessarily present in the volatile matter.) Thus the components of the proximate analysis have to add up to 100%. 

Proximate analysis - a relatively low-cost analysis in which moisture content, volatile combustible matter, fixed carbon, and ash are determined. The fuel value of the sludge is calculated as the weighted average of the fuel values of its individual components. 

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