Title:
高炉操業方法
Document Type and Number:
Japanese Patent JP5263430
Kind Code:
B2
Abstract:
A method for operating a blast furnace that makes it possible to further increase combustion temperature and reduce a unit consumption of reducing agent is provided. When two or more lances for injecting reducing agents from a tuyere are used, and LNG is used as a flammable reducing agent and pulverized coal is used as a solid reducing agent, a position of an end of the lance for injecting LNG is situated closer to a near side in a injecting direction by more than 0 to 50 mm than a position of an end of the lance for injecting pulverized coal. By this, the LNG effectively raises the temperature of the pulverized coal. The LNG contacts oxygen and undergoes combustion earlier, so that explosive diffusion occurs and the temperature of the pulverized coal is drastically increased. This makes it possible to drastically increase the combustion temperature and, thus, to reduce the unit consumption of reducing agent. In addition, when a double wall lance is used as a lance for injecting pulverized coal, the pulverized coal is injected from the inner tube and oxygen is injected from the outer tube, so that it is possible to provide oxygen necessary to the combustion of the pulverized coal and to further increase combustibility. The outlet flow velocity at the lance is 20 to 120 m/sec to prevent deformation of the lance.
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Inventors:
Akinori Murao
Fujiwara Taiki
Shiro Watanabe
Fujiwara Taiki
Shiro Watanabe
Application Number:
JP2012151797A
Publication Date:
August 14, 2013
Filing Date:
July 05, 2012
Export Citation:
Assignee:
jfe Steel Corporation
International Classes:
C21B5/00; C21B7/00
Domestic Patent References:
| JP2006241586A | ||||
| JP10226806A | ||||
| JP6128614A |
Attorney, Agent or Firm:
Tetsuya Mori
Megumi Konishi
Hide Tanaka Tetsu
Ichi Hirose
Toru Miyasaka
Megumi Konishi
Hide Tanaka Tetsu
Ichi Hirose
Toru Miyasaka