Proximate free moisture

Thus, to classify coal, the calorific value and a proximate analysis (moisture, ash, volatile matter, and fixed carbon by difference) are needed. For lower-rank coals, the equilibrium moisture must also be determined. To calculate these values to a mineral-matter-free basis, the Parr formulas are used (ASTM D-388). 

Each of these is reported in the proximate analysis. Coal analyses can be reported on several bases as-received, moisture-free (or dry), and mineral-matter-free (or ash-free). 

Nearly all the coals examined are relatively high in ash. Only two of the samples from the Terrace Ridge area contain less than 20% ash, on a moisture-free basis. Most of the remaining samples from this area range from impure coal to coaly shale. Most of the mineral matter is finely divided (dehydrated) clay, silica, and pyrrhotite. This is an important point since the proximate and ultimate analyses for material that deviates so widely from what is normally considered coal cannot be considered particularly reliable for comparison pur-... 

Proximate (approximate) analysis is a scheme developed originally in 1865 by Henneberg and Stohmann of the Weende Experiment Station in Germany to analyse the main components. It is often referred to as the Weende System and has been refined over time. The system consists of determinations of water (moisture), ash, crude fat (ether extract), CP and crude fibre (CF). It attempts to separate carbohydrates into two broad classifications CF (indigestible carbohydrate) and N-free extract (NFE, or digestible carbohydrate). NFE is measured by difference rather than by direct analysis. 

All experiments in dilute-phase hydrogasification used a feed of Pittsburgh seam coal having a free-swelling index of 8 and a volatile content of 41% moisture- ash-free basis. Ultimate and proximate analyses... 

Proximate Analysis - A commonly used analysis for reporting fuel properties may be on a dry (moisture free) basis, as "fired", or on an ash and moisture free basis. Fractions usually reported include volatile matter, fixed carbon, moisture, ash, and heating value (higher heating value). 

Proximate analysis The determination by prescribed methods of moisture, volatile matter, fixed carbon (by difference), and ash unless specified, proximate analyses do not include determinations of sulfur or phosphorous or any determinations other than those named proximate analyses are reported by percent and on as-received, moisture-free, and moisture- and ash-free bases. 

FC). The proximate analysis is usually reported as percentages (or fractions) of the four quantities, that is, moisture, ash, volatile matter, and fixed carbon. The ultimate analysis is a chemical analysis that provides the elemental mass fractions of C, H, N, O, and S usually on a dry, ash-free basis. 

Table 2.3 Proximate and ultimate analysis of five Canadian coals (moisture free)...

The conversion factors for the individual bases are given in Table 3.3. Any quantity from a proximate or ultimate analysis (X) can be converted from the given basis by multiplying with the indicated factor to a new desired basis. As an example, Equation (3.3) shows the conversion of the volatile matter determined at air-dried basis VM(ad) to water-and-ash-free basis, taking moisture W(ad) and ash A(ad) into account. 

The cellulosic shell comprises about 20-30% of the weight of the mature peanut. The proximate composition of peanut shells has been reported on a moisture-free basis, as follows protein, 5-7.3% ether extract, 1.2-2.1% crude fiber, 66-80% nitrogen-free extract, 10.6-21.2% ash, 3-4.6%. The presence of reducing sugars, 0.6%, disaccharide sugars, 1.7%, starch, 0.7%, and pentosans, 18%, has also been reported (26-27, 84,92,100,187). 

The nitrogen-free extract comprises nonfibrous soluble carbohydrates (starch, monosaccharides, and disaccharides). In the proximate analysis, the NFE is calculated by difference (NFE = 100 — % moisture — % crude protein — % fat or ether extract — % crude fiber — % ash). 

Typically, petroleum residue is characterized by proximate analysis, which only quantifies the fraction of fuel material (FM), ash and moisture, and elemental (ultimate) analysis (C, H, O, N, S). In the proximate analysis, the fuel fraction is usually divided into two parts fixed carbon (FC) and volatile material (VM). For calculation purposes, both fractions are totalized as ash-free dry fuel matter (expressed in weight%). With the elemental analysis (reported in weight% dry basis for each element), it is possible to obtain the condensed formula of the fuel fraction and thus its molecular weight. 

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