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LABORATORY WORKS ACCORDING TO THE SYLABBUS OF THE
SUBJECT “MATERIAL SCIENCE”
Laboratory work -1
Topic: Study of cast iron production technology.
The purpose of the work:
to get acquainted with the structure of the blast furnace
and study the technology of production of
cast iron in it
Necessary tools.
1. Blast furnace , 2. Iron ore, 3. Manganese ore, 4. Limestone,
5. Coke ore
Theoretical information.
A blast furnace is a mine furnace that operates continuously for 5-10 years and
has an average volume of 2000-3000m
3
. But in the following years, even larger
blast furnaces are being built.
For example: since 1974, a blast furnace with a useful volume of 5000 m
3
has
been operating at the Krivoy Rog metallurgical combine. In 1986,
the fifth blast
furnace named " Severyanka" was put into operation at the Chereovetsk
metallurgical plant . This blast furnace is one of the largest furnaces in the world,
with a useful volume of 5580 m
3
, a height of more than 100 meters, a diameter of
19 meters, equipped with modern automatic mechanisms. It produces 10,000-12,000
tons per day, 4-4.5 million tons of cast iron per year.
Figure 1.1 shows the general view of the blast furnace. The wall of the blast
furnace is made of fire-resistant fireclay bricks, the inner surface is plastered with
fire-resistant clay, and the surface is welded and fastened with a 20-40 mm steel
sheet.
in order to increase the durability of the refractory bricks of the furnace (in ¾
of the height of the furnace), cooling pipes are installed
inside the wall and cold
water circulates in them.
When the blast furnace is working, the gases released go to the gas cleaning
system through the pipes installed in the blast furnace.
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Ore and coke particles are collected at the bottom of the cylinder as it slows
down as it passes through the large cylinder, but these gases are followed by ore and
coke dust . Therefore, in
order to clean it more cleanly, the gas is separated in
cylinders called scrubbers and moistened with a water spray. For better cleaning, the
gas is passed through a high-voltage electric field created between two electrodes.
In this case, electrically charged solid particles are thrown to one of the electrodes
under the influence of an electric field. The gas thus purified is used as fuel. In the
gas cleaning stage, blast furnace gases are sent through special pipes to air heaters.
The largest part of the
furnace with a truncated cone, which expands downwards, is
called a shaft 4. Such a construction helps the frost to fall down as it melts.
This part, in turn, is connected to the lower cylindrical part 5, which is called
rasar.
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