phosphates, sulfates, sulfides and iron, calcium, aluminum, potassium, sodium, and
some other chemical compounds different elements.
Technical analysis of solid fuels with basic data analysis gives the first rough idea
of its structure and technical values. Typically, technical analysis boils down to
determine the moisture content W, A ash, volatile matter V, S and sulfur content
calorific value Q. The data related to a particular class of fuel, working, or air dry
completely. Operational called a fuel that is not subjected drying. These technical
analysis attributed to such fuel indicated Wp, Ap, Vp, etc.
Air-called dry fuel, which is obtained as a result of laboratory tests for drying 70-
75 ° C in the oven and then at room temperature in air. In this case, the fuel moisture
content is determined by its hygroscopic. These technical analysis thus meant WA,
Aa, Vat.d.
Absolutely-called dry fuel, which is obtained as a result of laboratory tests drying
105 ° C to constant weight. Ash content and quantity of volatile designed to completely
dry fuel, denoted respectively Ace, vc.
In some cases, the amount of volatile substances include organic matter into fuel
(combustible portion of fuel) and denoted by Vi [4].
Wet and method of its determination.
This paper should be familiar with the standard methods for determining the
moisture, ash, volatile matter and sulfur in fuels made from pre-prepared medium
samples of solid fuel. All analyzes conducted with two sample.
There are external coal, hygroscopic and chemically bound moisture. Foreign
moisture usually covers grains of coal in the form of a thin film and is released when
fuels are given to air-dry state. Hygroscopic moisture absorbed carbon from the
environment, depending on relative humidity and ambient temperature. Chemically
bound moisture is part of the coal or mineral composition of impurities contained in
it, such as water of crystallization is called internal or constitutional.
Moisture in coal varies very widely and lignite reaches 30-40%. The presence of
moisture reduces the content of nutrients and fuel its calorific value increases the
overhead in transportation, coal preparation difficult, and significantly alters the rate
of coking and hence performance coke ovens. Humidity fuel can be determined
directly or indirectly by.
When moisture by weight by direct fuel sample is dried in a stream of inert gas
(usually nitrogen) at 105-110 ° C, and the color of water vapor absorb magnesium
chloride or sulfuric acid in the gas is passed through two containers (tubes) with
absorber: primary, which absorbed the bulk of the moisture and control, which caught
residues (traces) moisture.
By increasing mass absorber calculated moisture content in fuel by the formula:
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