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US 4,227,921 AGranted
Method of controlling a blast furnace operation
AssigneeSumitomo Kinzoku Kogyo Kabushiki Kaisha
InventorsYoshiyuki Matoba, Koichi Otsuka
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Abstract
This invention relates to a method of controlling blast furnace operation by manipulating the following variables: oil injection rate, blast moisture, blast oxygen rate, blast rate blast temperature and ore/coke ratio.
Claims7
A method of controlling blast furnace operation by changing the value of the following manipulating variables:
- oil injection rate, blast moisture, blast oxygen rate, blast rate, blast temperature and ore/coke ratio, the method comprising:
- (A) assuming a process model on the basis of the following conditions:
- (1) the working volume in the furnace is vertically subdivided into a plurality of horizontal zone,
- (2) in each zone, predetermined reactions proceed uniformly, and
- (3) said horizontal zones include a zone at the lower side in which carbon solution reaction (R4) and pig iron production reaction (R5) proceed;
- C+CO.sub.2 .fwdarw.2CO (R4)
- FeO+CO.fwdarw.Fe+CO.sub.2 (R 5)
- (B) conducting measurements and analyses to obtain the following process data:
- the charge data, top gas data, blast data and tap data.
- (C) predicting the future temperature Ti of the i-th zone by the steps of:
- (1) calculating the reaction rates R4 and R5 at present from said process data,
- (2) predetermining the step response characteristic of the reaction rates R4 and R5 when changing the values of the maniplating variables,
- (3) calculating the future reaction rates R4 and R5 from the present reaction rates R4 and R5 and said step response characteristics,
- (4) calculating the other future reaction rates Rm from the future reaction rates R4 and R5 and the manipulating variables,
- (5) calculating the future temperature Ti of the i-th zone from the future reaction rates Rm and the manipulating variables, on the basis of the material and heat balance equations applied to the model,
- (D) changing the value of at least one of the manipulating variables to control the temperature of i-th zone according to the following equation:
- ##EQU18## where U*:
- value of manipulating variable after change
- U.degree.:
- value of manipulating variable at present time
- G.sub.u.sup.j :
- coefficient
- Ti*:
- target temperature of i-th zone
- Ti.sup.j :
- predicted temperature of i-th zone at future time j.
23 more elements
A method of controlling blast furnace operation by changing the value of the following manipulating variables:
- oil injection rate, blast moisture, blast oxygen rate, blast rate, blast temperature and ore/coke ratio, the method comprising:
- (A) assuming a process model on the basis of the following condition:
- (1) the working volume on the furnace is vertically subdivided into a plurality of horizontal zones,
- (2) in each zone, predetermined reactions proceed uniformly, and
- (3) said horizontal zones include a zone at the lower side in which carbon solution reaction (R4) and pig iron production reaction (R5) proceed;
- C+CO.sub.2 .fwdarw.2CO (R4)
- FeO+CO.fwdarw.Fe+CO.sub.2 (R 5)
- (B) conducting measurements and analyses to obtain the following process data;
- the charge data, top gas data, blast data and tap data,
- (C) calculating the temperature TSn of the solid in the lowest zone by the steps of:
- (1) calculating the reaction rates Rm from the process data, and
- (2) calculating the temperature TSn from the process data and the reaction rates Rm on the basis of the material and heat balance equations applied to the model,
- (D) predicting the future temperature TSn of the solid in the lowest zone by the steps of;
- (1) predetermining the step response characteristics of the reaction rates R4 and R5 when changing the values of the manipulating variables,
- (2) calculating the future reaction rates R4 and R5 from the present reaction rates R4 and R5 and said step response characteristics,
- (3) calculating the future reaction rates Rm of the reaction (Rm) in the zones from the future reaction rates R4 and R5 and the manipulating variables,
- (4) calculating the future temperature TSn from the future reaction rates Rm, the process data and on the basis of the material and heat balance equations applied to the model,
- (E) predecting the future pig iron temperature T.sub.pig by the following equation:
- T.sub.pig.sup.j =TS.sub.n.sup.j -.delta.T.sub.pig.sup.-1
- .delta.T.sub.pig.sup.-1 =TSn.sup.-1 -T.sub.pig.sup.-1
- wherein
- T.sub.pig.sup.j :
- predicted temperature of pig iron tapped at future time j,
- TS.sub.n.sup.j :
- predicted temperature of the solid in the lowest zone at future time j,
- T.sub.pig.sup.-1 :
- actual pig iron temperature of the latest tap
- TSn.sup.-1 :
- calculated temperature of the solid in the lowest zone at the time of the latest tap
- (F) changing the value of at least one of the manipulating varialbes to control the temperature of pig iron according to the following equation;
- ##EQU19## where U*:
- value of manipulating variable after the change
- U.degree.:
- value of manipulating variable at present time
- G.sub.u.sup.j :
- coefficient
- T.sub.pig *:
- target temperature of pig iron
35 more elements
A method of controlling a blast furnace operation by changing the value of the following manipulating variables;
- oil injection rate, blast moisture, blast oxygen rate, blast rate, blast temperature and ore/coke ratio, the method comprising:
- (A) assuming a process model on the basis of the following conditions:
- (1) the working volume in the furnace is vertically subdivided into a plurality of horizontal zones,
- (2) In each zone, predetermined reactions proceed uniformly, and
- (3) said horizontal zones include a zone at the lower side in which carbon solution reaction (R4) and pig iron production reaction (R5) proceed;
- C+CO.sub.2 .fwdarw.2CO (R4)
- FeO+CO.fwdarw.Fe+CO.sub.2 (R 5)
- (B) conducting measurements and analyses to obtain the following process data:
- the charge data, top gas data, blast data and tap data.
- (C) calculating the temperature TSn of the solid in the lowest zone by the steps of;
- (1) calculating the reaction rates Rm from the process data, and
- (2) calculating the temperature TSn from the process data and the reaction rates Rm on the basis of the material and heat balance equations applied to the model,
- (D) predicting the future temperature TSn of the solid in the lowest zone by the steps of:
- (1) predetermining the step response characteristics of the reaction rates R4 and R5 when changing the values of the manipulating variables,
- (2) calculating the future reaction rates R4 and R5 from the present reaction rates R4 and R5 and said step response characteristics
- (3) calculating the future reaction rates Rm of the reaction (Rm) in the zones from the future reaction rates R4 and R5 and the manipulating variables,
- (4) calculating the future temperature TSn from the future reaction rates Rm, and the manipulating variables, on the basis of the material and heat balance equations applied to the model.
- (E) predicting the silicon content of the pig iron tapped in future by the following equations:
- Si.sup.j =C.sub.1 TS.sub.5.sup.j +C.sub.2 -.delta.Si.sup.-1
- .delta.Si.sup.-1 =C.sub.1 TS.sub.5.sup.-1 +C.sub.2 -Si.sup.-1
- wherein
- Si.sup.j :
- predicted silicon content of the pig iron tapped at tuture time j
- TSn.sup.j :
- predicted temperature of the solid in the lowest zone at future time j
- Si.sup.-1 :
- actual silicon content of the pig iron of the latest tap1
- TSn.sup.-1 :
- calculated temperature of the solid in the lowest zone at the time of the latest tap
- C.sub.1, C.sub.2 :
- constant
- (F) changing the value of at least one of the manipulating variables to control the silicon content of pig iron according to the following equation:
- ##EQU20## wherein U*:
- value of the manipulating variable after the change
- U.degree.:
- value of the manipulating variable at present time
- G.sub.u.sup.j :
- coefficient
- Si*:
- target silicon content of pig iron
37 more elements
Dependencies are inferred from the claim text.