characteristics of coking coal and use of agricultural waste for power generation
Coking Coal
A Coking coal is that coal which when heated in absence of air leaves a solid coherent residue possessing metallic grayish luster & which possesses all the physical & chemical properties in the coke when manufactured commercially. Coking coal are those coals which after heating in absence of air leaves a residual coke. This coke when satisfies all the physical & chemical characteristics such as CSR, CRI, Shutter Index, Micum 10 & 40 & Porosity, are accepted by the steel plants. The coal which produces such coke is termed as coking coal. Various properties of coals which gives rise to the manufacture of coke
Coking coal is divided into 3 sub-categories:
1.Primary Coking Coal (Low ash , low Volatile, High Coking property)
2.Medium Coking Coal (low ash, medium volatile, low caking index) and
3.Blendable/ Semi/Weak Coking Coal (low ash, high volatile, very low caking index).
Grades of Coking Coal
Steel Grade –I Not exceeding 15%
Steel Grade -II Exceeding 15% but not exceeding 18%
Washery Grade -I Exceeding 18% but not exceeding 21%
Washery Grade -II Exceeding 21% but not exceeding 24%
Washery Grade -III Exceeding 24% but not exceeding 28%
Washery Grade -IV Exceeding 28% but not exceeding 35%
Properties of coking coal
A) Chemical properties:
· Carbon: The elements carbon expressed on dry mineral matter free (DMMF)
· Hydrogen: The hydrogen DMMF basis should vary between 3.7 to 4.5%.
· Sulpher: In the suplher both organic & inorganic should not exceed 0.75% on DMMF basis.
· Phosphorous: The Phosphorous present in the coking coal should not exceed 0.15 – 0.25%.
· Other elements: Such as Nitrogen, Iron & Other rarer elements must be present in traces. B) Mineral Matter:
The mineral matter in the coking coal normally should not exceed 20% under any circumstances since the mineral matter constitute a portion of inert matter hence its quality should not exceeds 20%. There are 2 kinds of MM in the coal. (i) Inherent
A Coking coal is that coal which when heated in absence of air leaves a solid coherent residue possessing metallic grayish luster & which possesses all the physical & chemical properties in the coke when manufactured commercially. Coking coal are those coals which after heating in absence of air leaves a residual coke. This coke when satisfies all the physical & chemical characteristics such as CSR, CRI, Shutter Index, Micum 10 & 40 & Porosity, are accepted by the steel plants. The coal which produces such coke is termed as coking coal. Various properties of coals which gives rise to the manufacture of coke
Coking coal is divided into 3 sub-categories:
1.Primary Coking Coal (Low ash , low Volatile, High Coking property)
2.Medium Coking Coal (low ash, medium volatile, low caking index) and
3.Blendable/ Semi/Weak Coking Coal (low ash, high volatile, very low caking index).
Grades of Coking Coal
Steel Grade –I Not exceeding 15%
Steel Grade -II Exceeding 15% but not exceeding 18%
Washery Grade -I Exceeding 18% but not exceeding 21%
Washery Grade -II Exceeding 21% but not exceeding 24%
Washery Grade -III Exceeding 24% but not exceeding 28%
Washery Grade -IV Exceeding 28% but not exceeding 35%
Properties of coking coal
A) Chemical properties:
· Carbon: The elements carbon expressed on dry mineral matter free (DMMF)
· Hydrogen: The hydrogen DMMF basis should vary between 3.7 to 4.5%.
· Sulpher: In the suplher both organic & inorganic should not exceed 0.75% on DMMF basis.
· Phosphorous: The Phosphorous present in the coking coal should not exceed 0.15 – 0.25%.
· Other elements: Such as Nitrogen, Iron & Other rarer elements must be present in traces. B) Mineral Matter:
The mineral matter in the coking coal normally should not exceed 20% under any circumstances since the mineral matter constitute a portion of inert matter hence its quality should not exceeds 20%. There are 2 kinds of MM in the coal. (i) Inherent