Volatile matter composition

Figure 4. Relationship between volatile matter composition and temperature for a 150 X 200 mesh fraction of St. Nicholas anthracite...

Briquettes bum similarly to bituminous coal, although some tend to disintegrate on combustion. Alow (<6-7%) ash content increases the possibility of disintegration. Normal combustion depletes the combined oxygen and volatile matter in the coal quiddy, effectively changing its composition and combustion behavior, making control of combustion difficult. 

Moisture is lost and the chemical composition changes during coalification. Oxygen and hydrogen decrease and carbon increases. These compositional changes are accompanied by decreases in volatile matter and increases in calorific value. The volatile matter and calorific content are the main criteria used for commercial classification in the United States and for the International Classification. 

Properties Involving Utilization. Coal rank is the most important single property for appHcation of coal. Rank sets limits on many properties such as volatile matter, calorific value, and swelling and coking characteristics. Other properties of significance include grindabHity, ash content and composition, and sulfur content. 

Fig. 9. Composition of volatile matter as a function of rank (bright coals) at (a) 500°C and (b) 900°C. The wt % of C is on a dry ash-free basis of unheated...

Solids (Total Solids) the non-volatile matter in a coating composition, i.e. the ingredients of a coating composition which, after drying, are left behind and constitute the dry film. 

Specification. JAN-P-408 (1946) contains the following general requirements for Pentolite Volatile matter 0.5% max Composition 50 2% TNT Total acetone insol 0.04% max Inorganic acetone insol 0.02% max Acidity or Aikalinity 0.005% max Grit non PETN granulation thru No 30 sieve, 95% min thru No 200 sieve 30% max and Stability not more than 5ml of gas in 100° heat test... 

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. 

Coal Char Coal char is, generically, the nonagglomerated, non-fusible residue from the thermal treatment of coal however, it is more specifically the solid residue from low- or medium-temperature carbonization processes. Char is used as a fuel or a carbon source. Chars have compositions intermediate between those of coal and coke the volatile matter, sulfur content, and heating values of the chars are lower, and the ash content is higher, than those of the original coal. 

Many of the compositional parameters utilized as independent variables in the work cited above represented derived coal properties rather than fundamental chemical features. Further, variables traditionally used are often highly correlated with each other (for example volatile matter and hydrogen). As pointed out by Neavel (34) / this limits the utility of such parameters in correlational models. Instrumental techniques such as pyrolysis/mass spectrometry (35.36 C-n.m.r, FTIR, and... 

J. Gillies, 41, 6724 (1947) A primary ignition composition for igniting purposes, yielding little or no volatile matter among the products, of its combustion, consists of a mixture of CaSi2 and MN02 with or without CuO BritP 575506 (1946)... 

The coal-dust used for the tests is obtained by milling either coal from the Make-yevskii seam of the Tchaikino-South mine, which contains 29-35% volatile matter, less than 9% ash and less than 2% moisture, or another coal of the same composition. 

Calcination of the Ores.—The carbonated ores of this country arc generally prepared for the blast furnace by a process of calcination which burns away all volatile matters, and concentrates the metal. For this purpose the Ores are accumulated in large ]leaps, generally in an open field, and mixed with carbonaceous matters, each as small coal. Some of the black benda have sufficient coal in their composition to effect their calcination. After a heap of several hundred tons is oolleoted, a fire is kindled at the windward end, which gradually passes on through the whole mass and burns for several days, producing a very high heat, often sufficient to reduce and fuse some of the metal, which, however, is not desirable. 

In this paper the kinetics of volatile matter release from anthracites have been studied in some detail. Rates of volatile matter release from different particle sizes of anthracite as a function of heating rate and temperature have been measured. The change in composition of the volatile matter with volatilization temperature has been studied. 

Figure 6 shows the composition of the volatile matter released from a 150 X 200 mesh fraction of Woodward anthracite vs. temperature. The percentage of N2 analyzed is also shown. Some significant differences between Figures 6 and 4 are noted. For the Woodward anthracite, much larger percentages of CO and CO2 are found in the product gas released below 700°C. 

L. L. Newman Dr. Mackowsky has already asked you if you related your studies on the kinetics of volatile matter release from Pennsylvania anthracites to the petrographic constituents of the coal. Can you not say in effect that the coals from the various collieries differ from each other quite significantly with respect to their petrographic composition and that identification of a coal by source may identify it petrographically to some extent How do the results of these studies relate decrepitation actually experienced in industrial operations ... 

The composition of the various blends and the data resulting from the pyrolysis of the blends appear in Table II. Sulfur volatilization by fragmentation is not directly related to the volatile matter of the blend as was true with model compounds. For the same model compound (Ciba Orange R) in the various blends this factor is considered constant and has been neglected. 

Composition C, therefore, was replaced in the US by Composition C-2 which was a white plastic consisting of RDX 78.7% explosive plasticizer 21.3%. The expl plasticizer was composed of DNT 12.0%, TNT 5%, MNT 2.7%, NC (pyroxylin) 0.3% solvent 1.0%. Composition C-2 was plastic from -30° to 50°, but became less plastic at higher temp storage because of evapn of the volatile matter. Expl props of Comp C-2 are given in Ref 19, pp 53-4... 

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

The composition of the volatile matter evolved from coal is, of course, substantially different for the different ranks of coal, and the proportion of incombustible gases increases as the coal rank decreases. Furthermore, in macerals isolated from any one particular coal, the volatile matter content decreases in a specific order thus, exinite produces more volatile matter than vitrinite, which, in turn, yields more volatile matter than inertinite. 

---