Volatile substances and methods to determine their exit.
The volatiles were called vapor and gaseous products formed during heating fuel
without air. Exit volatiles largely depends on the conditions under which the
determination is carried out.
Of great importance is the temperature, heating rate, the amount of fuel pieces,
constructive design process of thermal decomposition of the fuel examined, etc. So
volatile yield should be determined strictly defined conditions. Exit volatile V for
different fuels varies widely (from 6 to 50% or higher).
The method determining the release of volatile substances in the coal enrichment
and waste is heated batch of fuel in porcelain crucibles at 850 ± 25 ° C for 7 min.
followed by the establishment in weight loss. Coal sample of 1 g of known humidity
(WA) weighed to within ± 0,01 g in a porcelain crucible height 40 and 30 mm in
diameter.
Before putting in the oven, pot close lid, which does not prevent the release of
volatile crucible because it is free. The output of volatile products from the furnace
provided the holes or slots in the cover. To measure temperature using a thermocouple,
which hot end should be at a distance of 10-20 mm from the top of the furnace. [8]
After heating for 7 minutes. pot, cover, take out of oven and cool initially within
less than 5 minutes. in the air, then in a desiccator to room temperature. The cooled
crucible containing therein the solid residue weighing (weighing all performed with
accuracy 0,0002 g). Out of volatile material in the sample of fuel is determined by the
formula,%
V
a
=
G
1
∗100
G
−W
a
(6)
(In carbon dioxide content of carbonates in the sample is less than 2%)
where G - the weight of fuel, g;
G1 - crucible loss in weight of a sample of fuel g
WA - moisture content in the studied sample,%.
In conventional mass combustible fuel:
V
P
=V
a
=
100
100−W
a
−A
a
(7)
where Aa mentioned study sample.
In the work the study sample isolated from recycled coal ash waste in terms of
reuse.
Table 3 shows the technical characteristics of samples of recycled coal. An
ultimate calculation results of the parallel tests.
When determining the ash content (essentially burning test) was observed "
the
fired " Some particles (like small firecrackers), and then remained in the boat should
be. Ash color - brown with occasional bright light inclusions. We can assume that a
sample of the mineral, which is half are mainly iron oxides and Al, Si, Ca and others.
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