Method for blending coals for cokemaking and method for producing coke

Patent metadata

Field	Value
Publication number	US-9845439-B2
Application number	US-201314387742-A
Country	US
Kind code	B2
Filing date	Mar 25, 2013
Priority date	Mar 27, 2012
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

Provided is a technique by which the compatibility between coals for cokemaking can be quantitatively determined to estimate the coke strength taking into account the compatibility and to select and blend coals based on the coke strength estimated taking into account the compatibility, thereby allowing the production of a coke with the desired strength. A method for blending coals for cokemaking includes predicting the strength of a coke to be produced from a blend of a plurality of coals based on a difference between the surface tensions of the plurality of coals after heat treatment and determining the types and proportions of the coals to be blended.

First claim

The invention claimed is:

1. A method for blending coals for cokemaking, comprising:
determining a percentage of each of a plurality of coals to be blended, based on a difference between surface tensions of semicokes prepared from each of the plurality of coals; and
blending the plurality of coals according to the percentages.

2. The method for blending coals for cokemaking according to claim 1 , further comprising:
selecting an additional coal such that the difference between the surface tension of a semicoke prepared from the additional coal and the average of surface tensions of semicokes prepared from the plurality of coal is 1.5 mN/m or less; and
blending the additional coal with the plurality of coals.

3. The method for blending coals for cokemaking according to claim 1 , wherein the surface tensions of the semicokes prepared from each of the plurality of coals fall within the range of (average−1.5) mN/m to (average+1.5) mN/m, where average is the average surface tension of all of the semicokes taken together.

4. The method for blending coals for cokemaking according to claim 1 , wherein 70% or more by mass of the plurality of coals are coals whose semicokes have surface tensions differing from the average of the surface tensions of semicokes of all of the plurality of coals by 0.8 mN/m or less.

5. The method for blending coals for cokemaking according to claim 1 , wherein a total surface tension difference S determined according to equation (1) is 1.0 mN/m or less:

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where w i and w j are the percentages of an i-th coal and a j-th coal in the blend, respectively, Δγ ij is the absolute difference between the surface tensions of the semicokes prepared from the i-th coal and the j-th coal, and n is the number of coals in the plurality of coals.

6. A method for producing a coke, comprising carbonizing the coals blended by the method for blending coals for cokemaking according to claim 1 to produce a coke.

7. A method for producing a coke, comprising carbonizing the coals blended by the method for blending coals for cokemaking according to claim 2 to produce a coke.

8. A method for producing a coke, comprising carbonizing the coals blended by the method for blending coals for cokemaking according to claim 3 to produce a coke.

9. A method for producing a coke, comprising carbonizing the coals blended by the method for blending coals for cokemaking according to claim 4 to produce a coke.

10. A method for producing a coke, comprising carbonizing the coals blended by the method for blending coals for cokemaking according to claim 5 to produce a coke.

Assignees

• Jfe Steel Corp

Inventors

• Shimoyama Izumi
• Anyashiki Takashi
• Fukada Kiyoshi
• Fujimoto Hidekazu
• Yamamoto Tetsuya
• Sumi Hiroyuki

Classifications

• G01N33/222

  Solid fuels, e.g. coal · CPC title

• C10L9/10

  by using additives · CPC title

• C10L5/04 Primary

  Raw material {of mineral origin} to be used; Pretreatment thereof {(pretreatment of fuels of non-mineral origin C10L5/40)} · CPC title

• C10L2300/20

  Mixture of two components · CPC title

• C10B57/04 Primary

  using charges of special composition · CPC title