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How to deal with the total moisture coal sample?

After the total moisture sampling, the sample should be prepared and analyzed at once or placed into the sealed clean container without contamination. What is more, the coal sample quality is required to be marked on the container.
How to get the total moisture coal sample alone from the coal flow?

Take the total moisture coal sample from the coal flow according to the time-based or quality-based sampling method. Increments number shall be at least 10 pieces for every 1000t. When the coal is over 1000t, the increments shall be calculated as the following formula:

N=n×(m/1000)1/2

where:
N---Increments quantity that should be sampled;
n---Increments quantity selected according to the coal types and ash determination regulation;
m---True Coal Quality, t.

When the coal is less than 1000t, sample at least 6 pieces coal samples. Increments quality can be adjusted by the nominal top size.
What is the significance of ash fusibility determination?

1. Provide a safety basis for furnace design and gas temperature

2. Predict the coal slagging

3. Select coal for different combustion methods

4. Analyze the ash residue type
What is volatile cinder? What types does it have?

Volatile cinder is the residue in the crucible after volatile determination for coal sample.

It has 8 types:

1. powdery

2. adhesion

3. weakly caking

4. caking without fusion

5. caking with fusion without expansion

6. caking with slight-expansion and fusion

7. caking with medium-expansion and fusion

8. caking with strong-expansion and fusion
What are the methods of ash content determination in coal? Why the result differs with different methods?

Ash content determination includes slow ash method and quick ash method. The testing result data under quick ash method is a bit higher than slow ash method. What is more, with the increasing of Ca and S in coal , the higher value will increase too. That is because the SO₂ can not discharge in time under quick ash method, which shall be absorbed by Calcium Oxide.
After long term storage, what will happen to the coal quality?

1. Calorific value decreases

2. Volatile matter changes

3. Ash productivity increases

4. Element changes

5. Anti-crushing strength decreases

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How to deal with the total moisture coal sample?

How to get the total moisture coal sample alone from the coal flow?

What is the significance of ash fusibility determination?

What is volatile cinder? What types does it have?

What are the methods of ash content determination in coal? Why the result differs with different methods?

After long term storage, what will happen to the coal quality?