GB/T 212-2008 English PDF (GB/T212-2008)

Delivery: 3 seconds. Download true-PDF + Invoice.
Get QUOTATION in 1-minute: Click GB/T 212-2008
Historical versions: GB/T 212-2008
Preview True-PDF (Reload/Scroll if blank)

GB/T 212-2008: Proximate analysis of coal
GB/T 212-2008
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 73.040
D 21
GB/T 211-2008
Replacing GB/T 212-2001, GB/T 15334-1994, GB/T 18856.7-2002
Proximate analysis of coal
(ISO 11722:1999 Solid mineral fuels - Hard coal - Determination of moisture in
the general analysis test sample by drying in nitrogen, ISO 1171:1997 Solid
mineral fuels - Determination of ash, ISO 562:1998 Hard coal and coke -
Determination of volatile matter, NEQ)
ISSUED ON: JULY 29, 2008
IMPLEMENTED ON: APRIL 01, 2009
Issued by: General Administration of Quality Supervision, Inspection and
Quarantine;
Standardization Administration of PRC.
Table of Contents
Foreword ... 3 
1 Scope ... 5 
2 Normative references ... 5 
3 Determination of moisture ... 5 
4 Determination of ash ... 8 
5 Determination of volatiles ... 12 
6 Calculation of fixed carbon ... 16 
7 Conversion of air-dried base volatile matter into dry ash-free base volatile
matter and dried mineral-free base volatile matter ... 16 
8 Industrial analysis of coal water mixture ... 18 
Appendix A (Normative) Determination of moisture in coal - Microwave drying
method ... 21 
Appendix B (Normative) Fast ash tester ... 24 
Proximate analysis of coal
1 Scope
This standard specifies the methods for determining the moisture, ash, volatile
content of coal and coal water mixture as well as the method for calculating the
fixed carbon.
This standard applies to lignite, bituminous coal, anthracite, coal water mixture.
2 Normative references
The provisions in following documents become the provisions of this Standard
through reference in this Standard. For the dated references, the subsequent
amendments (excluding corrections) or revisions do not apply to this Standard;
however, parties who reach an agreement based on this Standard are
encouraged to study if the latest versions of these documents are applicable.
For undated references, the latest edition of the referenced document applies.
GB/T 218 Determination of carbonate carbon dioxide content in coal (GB/T
218-1996, eqv ISO 925:1980)
GB/T 7560 Determination of mineral matter in coal (GB/T 7560-2001, eqv
ISO 602:1983)
GB/T 18510 Guideline for the validation of alternative methods of analysis
for coal and coke
GB/T 18856.1 Test methods for quality of coal water mixture - Part 1:
Sampling for coal water mixture
3 Determination of moisture
This chapter specifies three methods for determining the moisture content of
coal. Among them, method A is applicable to all coal types; method B is only
applicable to bituminous coal and anthracite; microwave drying method (see
Appendix A) is suitable for rapid determination of moisture content of lignite and
bituminous coal.
In the case of arbitration analysis, it is necessary to use the method A to
determine the moisture content of the coal sample for general analysis test
when using the moisture of coal sample for general analysis test for calibration
3.1.4 Test procedure
3.1.4.1 In a pre-dried and weighed weighing bottle, weigh (1 ± 0.1) g of coal
sample for general analysis test which has a particle size of less than 0.2 mm,
accurate to 0.0002 g; spread it flatly in the weighing bottle.
3.1.4.2 Open the lid of the weighing bottle and put it into a drying box (3.1.3.1)
that has been pre-filled with dry nitrogen and heated to (105 ~ 110) °C.
Anthracite is dried for 1.5 hours, whilst lignite and anthracite are dried for 2
hours. At 10 min before putting the weighing bottle in the drying box, start
leading in nitrogen, at a flow rate of 15 times per hour.
3.1.4.3 Take out the weighing bottle from the drying box; immediately cover it;
put it in a desiccator and cool it to room temperature (about 20 min); weigh it.
3.1.4.4 Perform inspecting drying for 30 min each time, until the mass of the
continuously dried coal sample is not reduced by more than 0.0010 g or the
mass is increased. In the latter case, the previous mass is used as the basis for
calculation. When the moisture is less than 2.00%, no inspection drying is
necessary.
3.2 Method B (air drying method)
3.2.1 Method summary
Weigh a certain amount of coal sample for general analysis test; place them in
blast drying oven at (105 ~ 110) °C; dry them in an air stream to a constant
mass. The mass fraction of water is calculated from the mass loss of the coal
sample.
3.2.2 Instrumentation
3.2.2.1 Blast drying oven: It is equipped with an automatic temperature control
device, which can keep the temperature in the range of (105 ~ 110) °C.
3.2.2.2 Glass weighing bottle: Same as 3.1.3.2.
3.2.2.3 Dryer: Same as 3.1.3.3.
3.2.2.4 Analytical balance: Same as 3.1.3.6.
3.2.3 Test procedure
3.2.3.1 In a pre-dried and weighed weighing bottle, weigh (1 ± 0.1) g of the coal
sample for general analysis test which has a particle size of less than 0.2 mm,
accurate to 0.0002 g; flatly spread it in the weighing bottle.
3.2.3.2 Open the lid of the weighing bottle and put it in a drying box (3.2.2.1)
0.2 mm, accurate to 0.002 g; evenly spread it in an ash dish, so that the mass
per square centimeter does not exceed 0.08 g.
4.2.1.3.4 Put the ash dish containing coal samples on the conveyor of the fast
ash tester, then the ash dish is automatically sent into the furnace.
4.2.1.3.5 When the ash dish is sent out of the furnace, remove it; place it on a
heat-resistant porcelain plate or asbestos plate; cool it in air for about 5 min.
Transfer it in a desiccator to cool it to room temperature (about 20 min). Weigh
it.
4.2.2 Method B
4.2.2.1 Method summary
The ash dish containing the coal sample is gradually sent from the outside of
the furnace into a muffle furnace which was preheated to (815 ± 10) °C and
ashed and burned to a constant mass. The mass fraction of the residue to the
mass of the coal sample is taken as the ash content of the coal sample.
4.2.2.2 Instruments and equipment: Same as 4.1.2.
4.2.2.3 Test procedure
4.2.2.3.1 In an ash dish pre-burned to a constant mass, weigh (1 ± 0.1) g of
coal sample for general analysis test with a particle size of less than 0.2 mm,
accurate to 0.0002 g. Uniformly and flatly spread it in an ash dish so that the
mass per square centimeter does not exceed 0.15 g. Dispense the ash dishes
containing coal samples on heat-resistant porcelain plates or asbestos plates
in advance.
4.2.2.3.2 Heat the muffle furnace to 850 °C; open the furnace door; slowly push
the heat-resistant porcelain plate or asbestos plate with the ash dish into the
muffle furnace; first place the coal sample in the first row of gray dish to ash.
When the coal sample no longer emits smoke after (5 ~ 10) minutes, push the
remaining rows of ash dishes sequentially into the hot part of the furnace at a
speed of not more than 2 cm per minute (if the coal sample catches fire, the
test shall be abolished).
4.2.2.3.3 Close the furnace door and leave a gap of about 15 mm in the furnace
door; burn it at (815 ± 15) °C for 40 minutes.
4.2.2.3.4 Take out the ash dish from the furnace; cool it in the air for about 5
minutes; move it into a desiccator to cool to room temperature (about 20
minutes); weigh it.
4.2.2.3.5 Perform inspective burning at (815 ± 10) °C for 20 min each time, until
the mass of the continuously dried coal sample is not changed by more than
required that the furnace temperature be restored to (900 ± 10) °C within 3 min,
then maintained at (900 ± 10) °C...