2 results listed
Integrated iron and steel industries have many plants
that generate more than one industrial waste, especially in the
iron production unit. Whereas some of these industrial wastes
are used in the iron-making process, some of them are stored in
open areas. Blast Furnace Sludge (BFS) and Tar Decanter
Sludge (TDS) are good examples as a waste material which are
stored in the open areas. These materials cannot be used in iron
and steel production due to some restrictive reasons. Within the
scope of the evaluation of these two wastes at the same time, a
serial of tests was carried out in the Moving Wall Coking Test
Oven at Erdemir and Isdemir Coal and Coke Laboratories. In
these tests, single seam coking coals (low, medium and high
volatile) were milled to be 85% below 3, 15 mm and the BFS was
fixed at 0.5% and the TDS was added in certain percentages. The
results obtained from the coke produced in the Moving Wall
Coking Test Oven were interpreted by considering Coke
Strength after Reaction (CSR), Coke Reactivity Index (CRI),
stability and hardness values.
International Iron & Steel Symposium
UDCS
Kenan Akgün
Tayfun Pamuksuz
Barış Avar
Ferhat Parlak
Can Erarslan
Safi Ahmet Çal
Blast furnaces are vertical melting furnaces and their capacities change according to their
height. They are used in the production of liquid raw iron by melting coke, limestone and iron
ore. High quality raw materials are demanded for the blast furnace operations and from one
of the raw materials, metallurgical coke, is produced in the batteries of coke plants.
Coke production take place by mixing low, medium and high volatile coking coal
in calculated proportions, than feeding this blend into closed system, airtight ovens and
heating the blend to 1250 ° C - 1350 ° C for 18-19 hours. In the coking process, first the
moisture in the coal is separated by vaporization, then the volatiles separates by gasification
after a series of cracking reactions. The final product is metallurgical coke which is rich in
carbon, porous and has a hard structure. The quality of the produced metallurgical coke is
directly affected by the coals used in the blend and the coking conditions.
Because of the increasing production targets and needs, integrated iron and steel plants can
supply metallurgical coke from outside producers. One of the most important input that increases
the cost of liquid raw iron is the amount of coke used in blast furnaces. The most important
parameters that determine the quality of the coke are CRI, CSR, Stability and Hardness.
Considering that the facilities provide coke from suppliers in order to meet their
production targets, the quality of the purchased coke affects the consumption in the
blast furnaces and has a direct negative or positive impact on the costs.
From time to time, it is observed that the analyses result of the four quality parameter
values mentioned above in the loading port and discharge port are not matched, the
discharge port sample’s analysis result are low than loading port. In such cases, the articles in the
contract are valid and buyer can accept the shipment with penalty or reject the raw materials.
In this study, the results of CRI, CSR, Stability and Hardness analysis are modeled from the
ash, volatile matter and ash components of coke and 77,14% - 77,30% - 91,51% - 80,8% R-square
values were obtained respectively. With the model a tool has been developed, which can be
used by the purchasing departments at the proposal evaluation stage.
International Iron & Steel Symposium
UDCS
Can Erarslan
Tayfun PAMUKÇU
Erdem YILDIZ