Specialized metallurgical processes – compositions for use therei – Processes – Process control responsive to sensed condition
Reexamination Certificate
2000-02-04
2001-08-14
Andrews, Melvyn (Department: 1742)
Specialized metallurgical processes, compositions for use therei
Processes
Process control responsive to sensed condition
C075S385000, C075S453000
Reexamination Certificate
active
06273931
ABSTRACT:
The invention relates to a method for controlling a smelting reduction process, in particular a cyclone converter furnace process for producing pig iron.
A smelting reduction process of the cyclone converter furnace process type is known for example from EP-A 0 690 136.
The object of the invention is to create a method for controlling a smelting reduction process.
With the invention this is achieved by:
measuring the carbon fraction C in the off-gas in the form of CO and CO
2
;
measuring the hydrogen fraction H
2
in the off-gas in the form of H
2
and H
2
O;
determining the C/H
2
ratio of the carbon fraction C and the hydrogen fraction H
2
in the off-gas;
comparing the C/H
2
ratio thus determined in the off-gas against the C/H
2
ratio prevailing for the coal being supplied, and
adjusting the coal supply based on the difference found in the C/H
2
ratios in the off-gas and the coal being supplied such that the fraction of char formed from the coal in the slag layers kept stable, the said fraction being not much less than 20%.
The advantage of this is that the char consumption of the smelting reduction process can be monitored on-line and that the coal supply of the smelting reduction process can be controlled automatically.
Preferably the C/H
2
ratio of the coal supplied is corrected for the carbon lossed by the conveyance by the off-gas, for the carbon dissolved in the pig iron, for carbon and/or hydrogen introduced together with additives, and for hydrogen introduced by water injection into the off-gas system before the sampling point. This achieves even better control of the process.
Preferably the coal supply is adjusted while lance height, ore and oxygen supply remain the same. The advantage of this is that the process runs stably.
REFERENCES:
patent: 5800592 (1998-09-01), den Hartog et al.
patent: 0384395 (1990-08-01), None
patent: 0690136 (1996-01-01), None
patent: 6506507 (1965-11-01), None
Patent Abstracts of Japan, vol. 014, No. 043, Jan. 26, 1990 for JP 01275711, published Nov. 6, 1989.
Patent Abstracts of Japan, vol. 013, No. 595, Dec. 27, 1989 for JP 01252715, published Oct. 9, 1989.
Andrews Melvyn
Corus Staal BV
Steven Davis Miller & Mosher LLP
LandOfFree
Method for controlling a smelting reduction process does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for controlling a smelting reduction process, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for controlling a smelting reduction process will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2483073