Development of technology of pulverized coal injection in Ukraine’s blast furnaces in variable liquid and gas dynamic conditions
The aim of the work is to study the features of the use of pulverized coal (PCI) in the conditions of the blast furnace (BF) No. 5 of Metinvest Holding Ltd (Ukraine).
Gespeichert in:
| Datum: | 2018 |
|---|---|
| Hauptverfasser: | , , |
| Format: | Artikel |
| Sprache: | Russian |
| Veröffentlicht: |
Інститут чорної металургії ім. З.І. Некрасова НАН України
2018
|
| Schriftenreihe: | Фундаментальные и прикладные проблемы черной металлургии |
| Schlagworte: | |
| Online Zugang: | http://dspace.nbuv.gov.ua/handle/123456789/160010 |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| Назва журналу: | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| Zitieren: | Development of technology of pulverized coal injection in Ukraine’s blast furnaces in variable liquid and gas dynamic condition / Yu.S. Semenov, Ie.I. Shumelchyk, V.V. Horupakha // Фундаментальные и прикладные проблемы черной металлургии: Сб. научн. тр. — Дніпро.: ІЧМ НАН України, 2018. — Вип. 32. — С. 28-41. — Бібліогр.: 11 назв. — англ. |
Institution
Digital Library of Periodicals of National Academy of Sciences of Ukraine| id |
irk-123456789-160010 |
|---|---|
| record_format |
dspace |
| spelling |
irk-123456789-1600102019-10-21T01:25:37Z Development of technology of pulverized coal injection in Ukraine’s blast furnaces in variable liquid and gas dynamic conditions Semenov, Yu.S. Shumelchyk, Ie.I. Horupakha, V.V. Производство чугуна The aim of the work is to study the features of the use of pulverized coal (PCI) in the conditions of the blast furnace (BF) No. 5 of Metinvest Holding Ltd (Ukraine). Целью работы является изучение особенностей использования пылеугольного топлива (ПУТ) в условиях доменной печи (ДП) № 5 компании "Метинвест Холдинг Лтд" (Украина). Метою роботи є вивчення особливостей використання пиловугільного палива (ПВП) в умовах доменної печі (ДП) № 5 компанії "Метінвест Холдинг Лтд" (Україна). 2018 Article Development of technology of pulverized coal injection in Ukraine’s blast furnaces in variable liquid and gas dynamic condition / Yu.S. Semenov, Ie.I. Shumelchyk, V.V. Horupakha // Фундаментальные и прикладные проблемы черной металлургии: Сб. научн. тр. — Дніпро.: ІЧМ НАН України, 2018. — Вип. 32. — С. 28-41. — Бібліогр.: 11 назв. — англ. 2522-9117 http://dspace.nbuv.gov.ua/handle/123456789/160010 662.6/9:536.7:669.162.21(477) ru Фундаментальные и прикладные проблемы черной металлургии Інститут чорної металургії ім. З.І. Некрасова НАН України |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| language |
Russian |
| topic |
Производство чугуна Производство чугуна |
| spellingShingle |
Производство чугуна Производство чугуна Semenov, Yu.S. Shumelchyk, Ie.I. Horupakha, V.V. Development of technology of pulverized coal injection in Ukraine’s blast furnaces in variable liquid and gas dynamic conditions Фундаментальные и прикладные проблемы черной металлургии |
| description |
The aim of the work is to study the features of the use of pulverized coal (PCI) in the conditions of the blast furnace (BF) No. 5 of Metinvest Holding Ltd (Ukraine). |
| format |
Article |
| author |
Semenov, Yu.S. Shumelchyk, Ie.I. Horupakha, V.V. |
| author_facet |
Semenov, Yu.S. Shumelchyk, Ie.I. Horupakha, V.V. |
| author_sort |
Semenov, Yu.S. |
| title |
Development of technology of pulverized coal injection in Ukraine’s blast furnaces in variable liquid and gas dynamic conditions |
| title_short |
Development of technology of pulverized coal injection in Ukraine’s blast furnaces in variable liquid and gas dynamic conditions |
| title_full |
Development of technology of pulverized coal injection in Ukraine’s blast furnaces in variable liquid and gas dynamic conditions |
| title_fullStr |
Development of technology of pulverized coal injection in Ukraine’s blast furnaces in variable liquid and gas dynamic conditions |
| title_full_unstemmed |
Development of technology of pulverized coal injection in Ukraine’s blast furnaces in variable liquid and gas dynamic conditions |
| title_sort |
development of technology of pulverized coal injection in ukraine’s blast furnaces in variable liquid and gas dynamic conditions |
| publisher |
Інститут чорної металургії ім. З.І. Некрасова НАН України |
| publishDate |
2018 |
| topic_facet |
Производство чугуна |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/160010 |
| citation_txt |
Development of technology of pulverized coal injection in Ukraine’s blast furnaces in variable liquid and gas dynamic condition / Yu.S. Semenov, Ie.I. Shumelchyk, V.V. Horupakha // Фундаментальные и прикладные проблемы черной металлургии: Сб. научн. тр. — Дніпро.: ІЧМ НАН України, 2018. — Вип. 32. — С. 28-41. — Бібліогр.: 11 назв. — англ. |
| series |
Фундаментальные и прикладные проблемы черной металлургии |
| work_keys_str_mv |
AT semenovyus developmentoftechnologyofpulverizedcoalinjectioninukrainesblastfurnacesinvariableliquidandgasdynamicconditions AT shumelchykiei developmentoftechnologyofpulverizedcoalinjectioninukrainesblastfurnacesinvariableliquidandgasdynamicconditions AT horupakhavv developmentoftechnologyofpulverizedcoalinjectioninukrainesblastfurnacesinvariableliquidandgasdynamicconditions |
| first_indexed |
2025-07-14T12:35:14Z |
| last_indexed |
2025-07-14T12:35:14Z |
| _version_ |
1837625785122291712 |
| fulltext |
28
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
UDC 662.6/9:536.7:669.162.21(477)
Yu.S.Semenov (Ph.D), Ie.I.Shumelchyk (Ph.D), V.V.Horupakha
DEVELOPMENT OF TECHNOLOGY OF PULVERIZED COAL INJECTION
IN UKRAINE'S BLAST FURNACES IN VARIABLE LIQUID AND GAS
DYNAMIC CONDITIONS
Z.I. Nekrasov Iron and Steel Institute, National Academy of Sciences of Ukraine
The aim of the work is to study the features of the use of pulverized coal (PCI) in
the conditions of the blast furnace (BF) No. 5 of Metinvest Holding Ltd (Ukraine). The
complex for the preparation and use of pulverized coal includes: a coal unloading and
storage area; coal mixing section; coal sampling unit; plot of coal sorting and
preparation; installation of drying and grinding coal raw materials, installation for the
injection of pulverized coal into the BF. It is shown that the use of rational modes of
loading and forming portions of the charge, the choice of rational slag mode allowed to
increase the annual consumption of pulverized coal on average up to 130 kg / t of pig
iron even in the conditions of variable load of BF and when working on coke of reduced
quality. During the research, an operational monitoring of the condition of the lining of
the BF shaft was carried out using the indications of the thermocouple of the lining and
the body of the refrigerators. The determination of the thermal loads of the cooling
system made it possible to develop measures to adjust the distribution of the charge
components along the radius and circumference of the furnace. The temperature of the
peripheral gas flow along the entire height of the furnace is reduced by an average of
13%, the irregularity of the peripheral temperature is reduced by 11%. The stability of
the cooling system and the smooth operation of the blast furnaces.
Keywords: blast furnace pulverized fuel, charge loading modes, lining
condition, thermal loads
Problem state. Blast furnace ironmaking of Ukraine is moving to the
technology of pulverized coal injection (PCI) in recent years. The development
of this technology occurs, mainly, in a difficult economic, organizational and
charge conditions. The operation of blast furnaces (BF) in Ukraine on
pulverized coal in such conditions requires a special approach to managing the
smelting process, that when equipped with modern means of control and
reasonable using of information obtained by these means, allows. It is allowed
to make effective decisions by technological personnel, both on changing the
parameters of the charging mode, and on correcting the blowing mode. It
should be especially recorded that the effective use of PCI along with the
requirements for the quality of coals, iron ore materials, blast furnace coke and
the design features of air tuyeres – their "height", diameter and angle of
inclination [1-3], is largely determined by the use of rational charging regimes
the realization of which is possible, mainly, by the bell-less charging devices,
which are uncontested in these conditions [4].
In one of the blast-furnace shops of Metinvest Holding Ltd (Ukraine), in
2016, the technology of blowing-in of the PCI was started: at ВF №5 from
01.03.2016 and at BF №3 from 20.04.2016. The main design characteristics
29
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
and the list of the main means of control of ВF №5 and BF №3 are shown in
Table.1.
Table 1. Basic design characteristics and control means of BF №5 and BF №3
Name BF №5 BF №3
Start after reconstruction, date June 29, 2007 October 18, 2011
Useful volume, m3 1513 1719
Shotcrete mine after start-up, date
October 2009, July
2011, November
2013, November 2016
June 2014,
September 2016
Radius of the top, m 3.40 3.60
Charging device Bell-type Bell-less top
Height of the cylindrical part of the
top, m
2,70 2,30
Height of the shaft, m 16,40 16,20
Number of cast iron, pcs. 2 2
Number of air jets, pcs. 20 24
Stationary thermo-probes above the
surface of charge charging, pcs.
4 4
Electromechanical probes, pcs. 2 1
Radar level gauges, pcs. 0 2
Gas outlets, pcs 4 4
Thermocouples of peripheral gas
flow, pcs.
16 16
Thermocouples of the lining of the
shaft, the spray and the shoulders,
pcs.
40+16*) 56
Thermocouples of the body of the
refrigerators of the mine, pcs.
30 –
*) - restored during the last repair with shotcrete the shaft, 16 thermocouples are additionally
duplicated in the heat-stressed zone (above the second cast-iron tap)
Summary of the main results of the study. The complex for the
preparation and injection of PCI into the furnaces of the blast furnaces of the
enterprise includes: a section for unloading and storing raw coal; a section for
mixing coal; installation of coal sampling; plot of screening and finishing of
coals; installation of drying and grinding of coal raw materials, equipped with
two vertical mills (capacity 52.5 t/h); installation of PC injection. The system
for blowing PCI into blast furnaces is equipped with a so-called Oxygen-coal
technology "OXYCOAL", the development of which is planned after the
relative stabilization of the supply of raw materials.
For the production of PCI in 2016, low-caking coals of the Bachatsky coal
mine were used, the composition and properties of which correspond to the
norms accepted in the world practice. Carbon content in the working weight of
these coals is 79.82%, ash content ≥ 8.5%, volatile matter content 22.1%, low
30
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
sulfur content 0.20%. It is worth mentioning two more important indicators
characterizing these coals, such as the Hardgrove grinding index (HGI) and the
free swelling index (FSI). The low-caking coals have an almost maximum level
of grindability, which greatly improves the tonnage of grinding and improves
the operating conditions of grinding media. Increasing the fineness of grinding
increases the degree of burn-in of the PCI particles, reducing energy costs,
which, along with other factors, allows increasing the PCI consumption to 160
kg/ton of cast iron and more. The index of free expansion of a coal particle of
this grade of coal improves the gas dynamics of the bottom of the furnace and
eliminates the coking of PCI in the blowing channel of air tuyeres.
Given the organizational and complex economic characteristics, the quality
of the coke used in the blast furnace shop did not meet the operational
requirements of the blast furnace technology using PCI. In Table. 2 shows the
characteristics of coke during the development of the technology of injection
PCI at BF №5 and BF №3 after the complete removal of natural gas from the
blast before the overhaul with shotcrete the shafts blast furnaces in comparison
with the required indicators of quality of coke when blowing the PCI.
Table 2. Quality of coke used at BF №5 and BF №3 during the development of PCI
technology
Coke quality index → BF↓ W Ash Sulfur М25 М10 > 80 0-25 CSR CRI
In accordance with
operational requirements
0,5 <12% S<0,6%, 87,0 6,0 5,0 3,5 >60%, <30
BF №5
PCI =110 kg/t of cast
iron
3,47 10,96 0,90 88,04 7,33 9,36 3,15 49,2 33,5
BF №3
PCI =110 kg/t of cast
iron
3,60 10,80 0,92 87,87 7,41 8,75 3,12 49,5 33,3
In addition, the quantitative and qualitative composition of iron ore used in
blast furnaces during this period was also unstable. The content of imported
pellets produced by Northern Iron Ore Enrichment Works by basicity
(CaO/SiO2) is 0.05 units. In a mixture with agglomerate changed from 10 to
75%, the amount of agglomerate produced by a local sinter plant with a basicity
of 1.4 units. With a high content of secondary resources necessitated additional
supplies of agglomerate of the production of Southern Mining and Processing
Plant with a basicity of 1.6 units, the total iron content in the burden with
limestone during the development of the PCI was 54.8%.
The transition to the PCI technology with an increase in the productivity of
blast furnaces with a reduced quality of charge materials and a low rate of
renewal of the coke nozzle necessitates flushing on an ongoing basis (so-called
"soft" flushes). In the blast furnace shop, in order to maintain the satisfactory
properties of the primary, intermediate and final slags, manganese-containing
materials, in particular manganese ore, are used in the blast furnace blend
31
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
composition. The manganese oxide of this ore reduces the viscosity of the
intermediate slags and reduces the melting point of the mixture of the iron ore
portion of the charge. In the second stage, when it enters the lower high-
temperature zone, part of manganese is reduced in it with gasification of carbon
in the lower part of the blast furnace, contributing to the acceleration of the
renewal of the coke nozzle and the stabilization of heating of the smelting
products.
Investigations of the influence of manganese in the blend when operating
on a combined blast in the conditions of the given metallurgical enterprise
before the start of the introduction of the PC injection technology showed that
under conditions of blast furnace operation on coke of reduced quality, an
increase in the MnO content in the charge by 1 kg/ton of cast iron reduces the
coke consumption by ~ 2,7–2,9 kg/t due to the organization of "soft" washing
of the furnace from coke of fine fractions and, as a consequence, stabilization
of heating of cast iron, the coefficient of transition of manganese to cast iron
was ~ 0.47 ± 0.03. The use of manganese-containing materials during the
development of the PC injection technology in an amount of ~ 25 kg/ton of cast
iron made it possible to increase the processability of blast furnace smelting
and to expand its management capabilities with unstable raw materials.
The transition to the technology of PC injection in the current conditions of
the blast furnace shop caused the need to adjust the charging regime on blast
furnaces. Under these conditions, when blowing into the hearth of a PCI, such
features of the distribution of the gas stream in the furnace as an insufficiently
developed central gas distribution and an excessively developed peripheral flow
of gases can take place. At the same time, it should be noted that the technology
of PC injection should provide for an increase in the productivity of the
furnace, one of the measures of achieving which is to provide a more developed
gas transmission capacity, in comparison with working without a PCI, the
peripheral zone of the furnace. And in order to achieve a smelting economy, the
degree of development of the central gas flow should provide the possibility of
regulating the dimensions of the axial coke outlet "without the risk of losing the
center". It is also important to note that when using PCI with a large amount of
slag at the output of smelting products (398 kg/ton of cast iron – at BF №5 and
393 kg/ton of cast iron – at BF №3), special modes of forming batch batches to
prevent particles from entering Not completely burned fuel into primary and
intermediate melts, which increases the probability of clogging the furnace with
non-melting masses.
Therefore, when regulating the distribution of the gas flow along the radius
of the furnace when blowing into the hearth of a PCI to achieve optimal
technical and economic parameters of melting, in the conditions of operation
characteristic for a given metallurgical enterprise, by distributing the charge
materials along the top section, it is necessary:
ensure a stable central gas distribution with a narrow axial coke vent;
32
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
to exclude the localization of individual types of iron ore raw materials
along the blast furnace top section;
provide an increased concentration of low-basic raw materials in the area
of localization of PCI particles;
to form the composition of iron-ore materials in the near-wall zone,
providing self-renewal of the skull in the lower part of the blast furnace
shaft;
optimize the gas permeability of the peripheral zone, not allowing
excessive "overcharging" of its iron ore materials, which can lead to "upper
suspensions" and an uneven collection of charge;
to ensure the development of a mutual flow of gases between the periphery
and the center.
Based on the above provisions for managing the distribution of gas flow
using PCI, the authors of this article have developed and proposed for
implementation: a new download program developed using the model system
[5] and the mode of formation of batches BF №3 (Figure 1). The need to
change the charging program was due to the formation of a "gas-tight"
intermediate zone in the furnace (zones of increased ore loads) during the
development of the PCI, which contributed to the development of an excessive
peripheral gas flow, which made it difficult for the gases to transfer from the
periphery to the center. These features of the distribution of the gas flow were
revealed during the analysis of the information of the temperature probe
installed on the furnace [6]. At the beginning of the development of the PCI,
the lining temperatures at the mid-well level and the thermal loads of the
cooling system in this zone also increased significantly.The implementation of
the proposed changes in the charging program and the mode of formation of
portions made it possible to reduce the temperatures of the peripheral gas
stream throughout the entire height of the furnace by 13%, from 432 °C to 377
°C, on an average, and to reduce the peripheral gas flow temperature
unevenness by 11% (Figure 2).
At the BF №3, the thermocouples of the lining of the shaft are established
by the height and circumference of the furnace, to a depth of 100 mm [7].
Thermocouples are installed on six horizons of the mine, as well as in the rasp,
shoulder and in the zone under tuyeres. The thermocouples are arranged around
the circumference of the furnace in the following way: eight thermocouples are
installed at the level of the shoulders, the decomposition and the three lower
horizons of the shaft, six thermocouples on the next two horizons and four
thermocouples on the upper horizon [7, 8].
Analysis of temperature changes in lining (peripheral gas flow) at BF №3
during the development of the PCI injection technology showed the following.
When blowing high flow rates (15–18 t/h), the temperature of the middle of the
shaft at two levels of the thermocouple installation increased from 215 °C to
550 °C, on average.
33
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
R – iron-containing materials, C – coke
Figure 1. Calculation structure of layers of charge materials, distribution of ore loads,
charge components along the radius of the furnace and charging matrices for two
rational modes of BF No. 3 (without PCI and PCI).
The change in the temperature of the thermocouples of the lining of the
first row of the bottom of the mine was characterized by a slight change in the
beginning of 2016, after which, on passing to the PCI, an unstable temperature
change was observed on this horizon. On the second row of the bottom of the
mine, an opposite pattern was observed, characterized by the stabilization of
temperatures and their root-mean-square deviation along the circumference
with the onset of PC injection.
34
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
Figure 2. Change in the temperature of the thermocouples of the lining of the mine, the
decontamination and the shoulders of BF №3 to (a) and after (b) the
implementation of the recommendations for charging
Such a feature of the temperature change in the lower part of the furnace
shaft could indicate a change in the position of the root of the zone of the
viscous-plastic state upon transition from the BF operation mode to the "gas-
free charge" with moistened blasting at the beginning of 2016 for technology
using natural gas and then PCI. At the same time, in conditions of blowing up
of large PCI expenses, all the temperatures of the bottom of the mine at two
levels increased from 215 °C to 390 °C, on average.
At the level of decomposition with increasing flow rate, the temperatures of
the lining thermocouples increased, on average, by 1.8 times (up to 310 °C),
compared to the beginning of 2016. The temperature of the lining
thermocouples at the level of the shoulders changed stably, this indicated the
presence of a stable skull in shoulders, which was then confirmed by visual
inspection of the mine after blowing. In absolute terms, the temperature at the
shoulder level increased slightly – from 125 °C to 175 °C.
35
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
Thus, it was found that at the mid, lower and lower levels in the transition
blowing and fuel modes of operation of the BF №3, including with the
beginning of injection of the PCI, significant changes were observed both in the
absolute values of the temperatures of the lining thermocouples and in their
standard deviations along the circumference furnace. This was a consequence
of both the change in the position of the root of the zone of the viscous-plastic
state and the deterioration of the lining of the mine, considering that at the time
of injection of large PCI costs, the mine shaft campaign was already two years,
which necessitated another shunting. The use in the technology of melting of
rational charging regimes during the injection of PCI made it possible to ensure
the operational stability of the cooling system and the trouble-free operation of
the blast furnace at the BF №3 without the lining of the shaft. After shotcrete
the shaft of BF №3 in September 2016, the distribution of liner temperatures
from the level of the shoulders to the upper horizon of the mine leveled, the
temperatures varied from 100 °C to 200 °C, until January 2017 inclusive.
In addition to the established features of the influence of the PCI on the
temperature changes of the liner over the height of the BF, in 2016, studies
were also made of the possibility of using the thermocouple indications for the
height of the BF shaft in the absence of a lining of the furnace shaft for
evaluating the processes in the peripheral zone of the furnace.
The investigations were carried out for the operating conditions of the
furnace in four periods, common for which was the absence of the lining of the
furnace shaft:
1. Mode of operation on "gas-free charge" with moistened blowing – the
steam consumption averaged 2.4 t/h (01.01–14.03.2016) – period 1.
2. Mode of operation with natural gas (NG) – NG consumption was, on
average, 58.9 m
3
/ton of cast iron (15.03–20.04.2016) – period 2
3. The operating mode with NG (10.8 m
3
/t) and with PCI (91.8 kg/ton of
cast iron) at the initial stage of its development (21.04-03.06.2016) –
period 3.
4. The mode of operation with the PCI (129.6 kg/ton of cast iron)
(29.06–13.09.2016) to stop the BF for shotcrete mine – period 4
In Fig.3a shows the distribution of the temperature of the gas flow in the
peripheral zone along the height of the BF for the four periods under study, in
Fig.3b – temperature distribution for the fourth period, conditionally divided
into three regimes with different consumption of the injected PCI. As can be
seen from Fig.3, the nature of the distribution of the temperature of the gas flow
in the peripheral zone along the height of the BF is largely determined by the
gas-blown mode and the amount of the PCI used.
36
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
Figure 3. Distribution of the temperature of the gas stream in the peripheral zone along
the height of the BF for various gas-blowing and fuel conditions
Thus, when analyzing the temperature of the gas flow of the bottom of the
shaft, the spray and the shoulders, the maximum value of the temperature (the
extremum of the curve) in the first period of work is marked at a level of 12 m
from the technological zero (TZ) – from the top of the protective plates of the
top, or 13 m from the axis of the air lances WF), in the second period - at a
level of 15 m from the TZ (10 m from the WF), in the third – at a level of 18 m
from the TZ (7 m from the WF), in the fourth period there was no clearly
pronounced extremum in the lower part of the furnace, the temperature The gas
37
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
flow monotonically increased from the shoulders to a level of 6 m from the TZ.
Extremes of the temperature curves of the lower zone of the furnace for the first
three periods of operation of the BF can characterize both the position of the
root of the zone of the viscous-plastic state (plastic zone) and the boundary of
the stable component of the garnish formed in the furnace. In favor of the
assumption about the position of the root of the zone of the viscous-plastic state
at the extremum point of the temperature curve, the results of investigations on
a BF with a working volume of 3594 m
3
of the Thyssen plant in Schwelgern
[9–11] testify. Determination of the position and profile of the plastic zone by
the authors of the publication [9, 10] was based on the distribution of pressures,
lining temperatures and gas composition at the wall along the height of the
furnace. On this BF, the lining temperatures of the mine were determined at 16
levels above the axis of the air tuyeres and at 13 levels the static pressure drops
were determined. According to the studies [9, 10], with a poor furnace stroke,
the height of the plastic zone, its upper limit, was 14 m above the level of the
tuyeres, at an average speed - at a distance of 9 m, with a good course – at a
distance of 8 m.
In addition, it should also be noted that in the first study period of the BF
operation, the maximum pellet content in the mixture with agglomerate
(54.8%) was used, which, as is known, has low melting properties and high
content in the charge Promotes the formation of a stretched over the height of
the plastic zone. And taking into account that the first period is characterized by
the maximum distance from the level of the tuyeres to the extremum point of
the temperature curve along the height of the lower part of the shaft, this may
also indicate the position of the upper boundary of the zone of the viscous-
plastic state at the extremum point.
An increase in the flow rate of the pulverized coal injected into the hearth
of the investigated BF (Fig.3b) contributed to an increase in the gas flow
temperatures along the furnace height with a maximum amplitude of the change
at the midpoint of the shaft. The increase in temperature was caused by the
intensification of the peripheral gas flow with increasing flow rate, and the
explanation for the maximum amplitude of temperature changes at the midpoint
of the shaft was the increased distance from the axis of the tuyeres to the
bending of the furnace profile and the rational design of the air tuyere used in
the blast furnace shop.
Thus, as a result of the performed studies, the effect of gas-blast furnace
parameters, including when using natural gas and pulverized fuel in the blast,
was shown to change the shape of the temperature distribution curve of the
peripheral gas stream. The established features of the influence of the features
of the gasdynamic mode of blast furnace smelting on the temperature of the gas
flow will allow to adequately detect and correctly monitor charging parameters
that influence the gas temperature distribution when the furnace load regime
changes.
38
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
In control system of BF №3, the indicator of total thermal loads of the
cooling system is registered, both in the furnace as a whole and in individual
zones. The performed analysis of the change in this indicator in 2016 showed
that at the initial stage of the development of PCI, the average daily values of
this indicator reached 10,000 kW per day. When the PCI costs reached 130–
140 kg/ton of cast iron on separate days, thermal loads increased, reaching its
maximum value for the whole period – 19180 kW. In October 2016, at the
output of BF №3 for the planned indicators for the daily capacity of the furnace
after repair, the total heat losses in terms of its value of 6000–9000 kW reached
the level of the beginning of 2016, when the technology of PCI melting was not
used. It should also be noted that the thermal loads of the middle zone play a
decisive role in the value of the indicator of the total thermal loads of the
cooling system, which is in agreement with the analysis of the lining
temperatures of the mine, from which it follows that the middle of the mine was
the most heat-directed zone along the height of BF №3 during the development
of the PCI. An explanation for this is the increased distance from the axis of the
air tuyeres to the profile bend (bottom of the shoulder) of the BF №3 and the
rational design solutions of the air tuyeres with a protrusion of 0.7 m, which are
characteristic for the blast furnace shop [8].
If the total thermal load of the cooling system is increased severalfold and
the lining temperatures are controlled at the same time, it is possible to judge
the wear of the lining of the shaft, the decontamination or the shoulders, and
plan technological and capital measures to prevent the failure of the cooling
plates of the thermally stressed zone. A significant increase in the value of this
indicator can explain the high consumption of conventional fuel, which will be
compensated for covering thermal losses.
Analysis of the state of the metal receivers of blast furnaces during the
development of the PCI showed the following. Since the start of the injection of
PCI at BF №5, the temperature of the central part of the floor has increased
slightly, but has not exceeded the maximum values observed on the furnace
earlier, which indicates the absence of wear of the liner. The temperature range
of the lining testified to a stable rational layer of the skull in the area. Thermal
loads in the most heat-stressed sector of the area, under the cast iron tapholes
remained at the level before injection of the PCI (~ 2000 W/m
2
). After the start
of PCI injection at BF №5, the temperature of the lining of the peripheral part
of the hearth and the floor at the levels from the third to the eighth level of the
thermocouple installation remained at the same level. Consequently, the
residual thickness of the lining did not change, the wear of the lining averaged
no more than 20%. After the start of the injection of PCI, a number of control
measurements of thermal loads on the cooling system of the furnace and floor
were carried out. The conducted measurements of the thermal loads on the
metal receiver refrigerators did not exceed the maximum values recorded
earlier in the furnace campaign since 2007. Due to the lack of automated
39
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
control and the noted tendency of growth of thermal loads on the refrigerators
of the furnace cooling system, it is recommended to conduct regular control
measurements of the thermal loads on the refrigerators of the cast iron chutes,
the lower and upper horns at the BF №5
Lining of the metal detector BF №3 is made of various refractory materials
from GrafTech International (USA) and NDK (Japan). The working surface of
the metal receiver is protected by a ceramic glass made by Saint Gobain
International (France). Since the beginning of the injection of the PCI into the
BF №3, the thermal load on the central part of the area has remained at the
same level, on the average, of the order of ~ 1500 W/m2. The wear of the lining
of the central part of the floor was absent, the surface of the floor was covered
by a layer of a skull. The main part of the thermal load on the peripheral
cooling refrigerators during the five years of operation of the BF №3 was stable
and did not exceed 20,000 W (in the bundle on the upper and lower floor
cooler) and 30,000 W (in combination with the upper and lower furnace
coolers). After the start of PCI, the temperature of the lining and the thermal
load on the refrigerators, including the refrigerators of the cast iron zone,
remained at the same level. The thickness of the lining of the peripheral part of
the horn and wood outside the iron casting sector remained projected and
covered with a layer of skull. In the sector of cast iron chambers, the
permissible wear of the ceramic layer is fixed – no more than 25%, caused by
the erosive effect of metal and slag flows.
CONCLUSION
The development of the PCI technology in the blast furnace shop Metinvest
Holding Ltd (Ukraine) in variable charge conditions and with work on reduced
quality coke with the use of rational charging regimes, forming portions and
selecting a rational slag regime, allowed to increase the consumption of PCI in
2016, on average, up to 130 kg/ton of cast iron. The operational control of the
state of the lining of the mine shaft of blast furnaces, carried out according to
the indications of the lining thermocouples, thermocouples of the body of
refrigerators and thermal loads of the cooling system, made it possible to carry
out both garbage-forming measures in time and to adjust the distribution of the
components of charge materials along the radius and circumference of the
furnace. The implementation of the proposed changes in the charging program
and the mode of formation of portions made it possible to reduce the
temperatures of the peripheral gas flow throughout the furnace altitude by an
average of 13% and reduce the circumferential temperature unevenness by
11%. The use in the technology of rational charging regimes during injection of
PCI allowed to ensure the operational stability of the cooling system and the
trouble-free operation of blast furnaces. The initial stage of PC injection in the
blast-furnace shop of Metinvest Holding Ltd (Ukraine) did not affect the heat
loads of the blast-furnace metal receivers. The performed analysis of the state
of the rock and borehole BF №3 showed the effectiveness of the design
40
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
solution for the use of a ceramic glass, the wear of which for five years of
operation of the furnace was 25% in the zones of the cast iron sectors.
1. A.L. Podkorytov, A.M. Kuznetsov, E.N. Dymchenko and etc. Technology for
preparing coke for blast furnace smelting and its efficiency // Metallurgist, July
2009, Volume 53, Issue 7–8, pp. 460–468.
2. A.L. Podkorytov, A.M. Kuznetsov, A.V. Zubenko and etc. Introduction of
Pulverized-Coal Injection at Yenakiieve Iron and Steel Works // Steel in
Translation, 2017. – Vol. 47, No. 5, pp. 313–319.
3. A.M. Kuznetsov, V.P. Padalka, A.V. Zubenko Ways of Improvement of Blast
Furnace Heat Techniques // Stal', 2007. – № 11. – pp. 6–7.
4. V.I. Bol'shakov Use of blast furnace technology in Ukraine with pulverized coal
injection // Digest of scientific works of the ISI NASU "Fundamental and applied
problems of ferrous metallurgy", 2011. – Volume. 23. – pp. 30–36.
5. Yu.S. Semenov, E.I. Shumelchik, V.I. Vishnyakov and etc. Model system for
selecting and correcting charging programs for blast furnaces equipped with a bell-
less charging apparatus // Metallurgist, January 2013, Volume 56, Issue 9-10,
pp. 652-657.
6. Yu.S. Semenov, E.I. Shumelchik, V.V. Horupakha and etc. Using Thermal Probes to
Regulate the Batch Distribution in a Blast Furnace with Pulverized-Coal Injection //
Steel in Translation, 2017. – Vol. 47, No. 6, pp. 389–393.
7. Yu.S. Semenov, N.M. Mozharenko, V.V. Gorupakha and etc. Effect of the Fuel, Raw
Materials, and Process Conditions on the Behavior of Temperature Change in a
Blast-Furnace Lining // Metallurgist, July 2015, Volume 59, Issue 3–4, pp. 290–
299.
8. Yu.S. Semenov, E.I. Shumel’chik, V.V. Gorupakha and etc. Monitoring Blast
Furnace Lining Condition During Five Years of Operation // Metallurgist, July
2017, Volume 61, Issue 3–4, pp. 291–297.
9. Yu.S. Semenov Temperature Distribution of the Gas Flux in Blast Furnaces – Steel
in Translation, 2017. – Vol. 47, No. 7, pp. 473–477.
10. E. Shyurman, G.V. Gudenau, K.-KH. Peters Investigation of a plastic zone at a blast
furnace in a plant in Schwelgern // – Chernyye metally, 1982. – № 6–7. – pp. 9–14.
11. E. Shyurman, G.V. Gudenau, K.-KH. Peters Dynamic change in the shape and
position of the plastic zone in the blast furnace // – Chernyye metally, 1982. –
№ 15/16. – pp. 17–20.
Ю.С.Семенов, Е.И.Шумельчик, В.В.Горупаха
Разработка технологии распыления пылеугольного угля в доменных
печах Украины в переменных жидких и газодинамических условиях
Целью работы является изучение особенностей использования пылеугольного
топлива (ПУТ) в условиях доменной печи (ДП) № 5 компании "Метинвест
Холдинг Лтд" (Украина). Комплекс для приготовления и использования
пылеугольного топлива включает в себя: участок разгрузки и хранения угля;
секцию для смешивания угля; установку отбора проб угля; участок сортировки и
подготовки углей; установку сушки и измельчения угольного сырья, установку
http://elibrary.ru/contents.asp?issueid=440110&selid=9600348
41
«Фундаментальные и прикладные проблемы черной металлургии»,
Сборник научных трудов ИЧМ. – 2018. - Вып.32
для инъекции ПУТ в ДП. Показано, что использование рациональных режимов
загрузки и формования порций шихты, выбор рационального шлакового режима
позволило увеличить годовое потребление ПУТ в среднем до 130 кг/т чугуна
даже в условиях переменной загрузки ДП и при работе на коксе пониженного
качества. Во время исследований проводился оперативный контроль состояния
футеровки шахты доменной печи с использованием показаний термопар
футеровки и корпуса холодильников. Определение тепловых нагрузок системы
охлаждения, позволило разработать мероприятия по корректировке распределения
компонентов шихты по радиусу и окружности печи. Температура периферийного
газового потока по всей высоте печи снижена в среднем на 13%, неравномерность
окружной температуры уменьшена на 11%. Обеспечена стабильность работы
системы охлаждения и бесперебойная работа доменных печей.
Ключевые слова: доменная печь пылеугольное топливо, режимы
загрузки шихты, состояние футеровки, тепловые нагрузки
Ю.С.Семенов, Є.І.Шумельчик, В.В.Горупаха
Розробка технології розпилення пиловугільного вугілля в доменних
печах України в змінних рідких і газодинамічних умовах
Метою роботи є вивчення особливостей використання пиловугільного палива
(ПВП) в умовах доменної печі (ДП) № 5 компанії "Метінвест Холдинг Лтд"
(Україна). Комплекс для приготування і використання пиловугільного палива
включає в себе: ділянку розвантаження і зберігання вугілля; секцію для
змішування вугілля; установку відбору проб вугілля; ділянку сортування і
підготовки вугілля; установку сушки та подрібнення вугільної сировини,
установку для ін'єкції ПВП в ДП. Показано, що використання раціональних
режимів завантаження і формування порцій шихти, вибір раціонального
шлакового режиму дозволило збільшити річне споживання ПВП в середньому до
130 кг / т чавуну навіть в умовах змінного завантаження ДП і при роботі на коксі
зниженої якості. Під час досліджень проводився оперативний контроль стану
футеровки шахти ДП з використанням показань термопар футерування і корпусу
холодильників. Визначення теплових навантажень системи охолодження
дозволило розробити заходи щодо коригування розподілу компонентів шихти по
радіусу і окружності печі. Температуру периферійного газового потоку по всій
висоті печі знижено в середньому на 13%, нерівномірність окружної температури
зменшено на 11%. Забезпечено стабільність роботи системи охолодження і
безперебійну роботу доменних печей.
Ключові слова: доменна піч пиловугільне паливо, режими завантаження
шихти, стан футеровки, теплові навантаження
The article was submitted to the editorial board of the collection on November 1,
2018; internal and external reviewing took place (Minutes of the meeting of the
editorial board of collection No. 1 of December 26, 2018)
Статья поступила в редакцию сборника 01.11.2018 года,
прошла внутреннее и внешнее рецензирование (Протокол заседания
редакционной коллегии сборника №1 от 26 декабря 2018 года)
Рецензенты: д.т.н., проф. А.К.Тараканов, к.т.н. А.С.Нестеров
|