Case Study

Calorific Value Determination in the Analysis of Coal and Coke

Sample Preparation
Crush & Grind the sample to size ≤ 0.2(GB) / 0.212(ISO) / 0.25mm (ASTM)  Air dried Moisture and total Moisture should be tested by oven and St,ad also should be tested by Sulfur analyzer

Instrument

5E-C5500 Automatic Calorimeter5E-C5508 Automatic Calorimeter

Instrument Settings
Pressure: 3 MPa
Nominal Sample Weight: (1±0.1) g
Analysis Time: 10~16min

Special Modifications to Unit
None

Method Approval

GB/T 213 ASTM D5865 AS1038.5 BIS 1350 ISO 1928

Procedure

1. Weigh the sample (sample should be press into pellet if easy splash when burning) in the crucible, with a weight around 1g which nearest to 0.1mg.
2. Fasten the ignition wire tautly between the electrodes in the bomb.
3. Add a specified amount of distilled water to bomb. (Water amount: 1mL when ISO and ASTM are applied, 5mL when GB is applied.)
4. Assemble the bomb and charge Oxygen into bomb. (For ISO, charging pressure 3.0 MPa. For GB, charging pressure is from2.8MPa to 3.0MPa. For ASTM, charging pressure is from 2.0MPa to 3.0MPa. )
5. Check the gas leak of the bomb.
6. Condition the instrument as below:
    a) Enter the analysis interface and preheat the instrument in advance for at least three times.  
    b) Do a waste sample after preheat.
    c) Test a benzoic acid sample to check the instrument.  
7.  Put the bomb into instrument, and input the sample weight and additive weight (if need) to the software and then analyze the sample.

Note
Do Calibrating refer to operator’s instruction manual for details.

Typical Results

Sample NameSample Weight(g)Calorific Value Qgr,d(J/g)
Coal1.017324758
1.024324749
1.051124753
1.043624760
Average Value24755