THE FUTURE WAYS OF STEELMAKING

The mining and metallurgical complex is a principal sector of the Ukraine’s economy. After the common economic zone of the former USSR collapsed, mining and metalmaking have actually turned into the backbone of the national economy for Ukraine.



THE FUTURE WAYS OF STEELMAKING

Vasily KHARAKHULAKH, Victor LESOVOI, Georgy MATUKHNO, Metallurgprom association; Vladimir POLYAKOV, the Institute for Ferrous Metallurgy under the Ukraine’s National Academy of Sciences; Boris BOYCHENKO, the National Metallurgical Academy of Ukraine

The mining and metallurgical complex is a principal sector of the Ukraine’s economy. After the common economic zone of the former USSR collapsed, mining and metalmaking have actually turned into the backbone of the national economy for Ukraine. Though back in 1990 outputs of machinery and equipment were more than 2.5 times ahead of mined and metal products, nowadays everything is vise versa. In 1993 mining and metalmaking accounted for 20% of Ukraine’s manufacturing output with this share gradually increasing further on and currently reaching 27 to 30%. All the prerequisites are in place to treat metallurgy, i.e. the sector manufacturing the bulk of commercial products in the complex, as a principal basic industry capable of gradually and inevitably driving into a recovery the whole mining and metalmaking complex, as well as metal-consuming sectors of the Ukrainian economy.

Specialists estimate that steel will remain the basic structural material both in the 21st century and in the long, long run. As long as this is acknowledged, it becomes extremely important to analyze the present and the future situation in Ukraine’s steelmaking.

Ukraine produced about 50 million tonnes (t) of steel in 1990, with open-hearth steel accounting for 54% of the total, basic oxygen steel making up 43%, and electric-arc steel contributing some more 3%. Back then, utilization of productive capacities was extremely high, e.g. some 98% for basis oxygen furnaces (BOF) compared to 68% in the USA, 64% in Japan, and 89% in the Federal Republic of Germany. Though the country was trailing behind in terms of continuous casting (e.g. 8.3% of the total steel was continuous-cast in Ukraine, 67.2% in the USA, 93.7% in Japan, and 91.4% in the FRG), the overall technical and manufacturing performance of Ukrainian steelmaking almost always rivaled the leading countries of the world, while the scope and the quality of research and development was sometimes even ahead of foreign R&D, though the rate of phasing the new developments in production processes was definitely behind the foreigners.

As Ukraine started economic adjustments trying to progress to market economy, especially since 1994, the situation in metallurgy and steelmaking changed for the worth, e.g. outputs slumped; supplies of raw materials, fuel, and power deteriorated; manufacturers started paying less attention to proper maintenance of machinery and equipment; while volume, scope, and application of research and development plunged.

Nonetheless, despite the deep and unhealthy recession, metallurgists have managed to keep up the main steelmaking capacities at 40 million t per year. The year 1999 saw output of 27 million t of steel with about equal portions of steel produced in BOFs and electric arc furnaces (EAF). Some 5 million t of steel were continuous cast. 19 BOFs are employed in Ukraine at this point of time. Though metallurgical mills of Ukraine own 59 open-hearths and tandem furnaces, only 42 of them can function, of which 28 to 34 furnaces were actually employed in steelmaking during various periods. As regards utilization of capacities, some 68.0% of the available open-hearth furnaces and 69.5% of BOFs are utilized in Ukraine.

As Donetsk Metallurgical Works wraps up reconstruction of electric arc furnaces, this mill will significantly boost output of electric arc steel, simultaneously slashing specific consumption of electric power. This upgrade came true after successful and efficient execution of a USD-55-million investment project in 1999 that involved public joint-stock company Donetsk Metallurgical Works and MetalsRussia. The big success of this investment project and the continuing cooperation pave the way for similar moves of other Ukrainian companies.

Unfortunately, one can state that the modern Ukrainian steelmaking is trailing behind the developed countries in terms of technologies and cost-efficiency. Nevertheless, Ukraine still ranks in the top ten global steelmakers. As of January 1, 1999, Ukraine ranked the seventh largest steel manufacturer in the world posterior to China with 111.6 million t of steel, Japan with 94.5 million t, the USA with 93.8 million t, Russia with 45.7 million t, Germany with 45.2 million t, and South Korea with 37.8 million t. As a rule, the majority of Ukrainian metallurgical mills use powerful steelmaking machinery frequently taking advantage of the up-to-the-minute technologies, such as out-of-furnace steel treatment, continuous casting, etc. Here is the proof – more than 80 types of Ukrainian-made construction, shipbuilding, and structural rolled steel articles, tubes and pipes, and various metal products have been certified by the renowned international classification societies, namely British and German Lloyd’s, American Shipbuilding Bureau, American Tube Institute, Norske Veritas, German TUF, Dutch TNO, etc. Besides, Ukrainian metal that has been tailor-treated to meet the customers’ standards, such as DIN, ASTM, JIS, etc., is successfully exported to the USA, China, France, Germany, Belgium, South America, Middle East, and Southeast Asia.

The concept for development of the Ukraine’s mining and metallurgical complex mentions the principal flaws of domestic metalmaking that ward it off from rivaling the developed countries. Steady deterioration of productive assets and shortage of current assets are the major menaces. The experience of Donetsk Metallurgical Works proves that the situation can be fundamentally altered only after metallurgical mills manage to replenish current assets and promote domestic and foreign investments in metalmaking. It is worth pointing out that the authorities gave real support to Ukrainian metallurgists with passing of the law on the economic experiment in mining and metalmaking. Improvement of enterprises’ financial health gives grounds to hope that the outlined program for restructuring and technical re-equipment of steelmaking facilities will be duly executed and phased in.

It has already been mentioned that the pattern of steel output, i.e. the ratio of steel made in BOFs, open-hearths, and EAFs, is the key factor determining the future development trends of Ukrainian steelmaking. Yet, it is completely impossible to give a simple and clear forecast in this case. This is proved by the two-year debate of almost all the leading CIS specialists in the Steel magazine. When it comes to global trends, the World Environmental Center insists that the international steelmaking pattern is as shown in table 1.

These figures unambiguously evidence the steadfast tendency towards lower portion of open-hearth steel and call for due assessment of the portion of electric-arc steel in Ukraine for the latter figure sticks to some 3% of the total steel output, which is definitely not enough.

Meanwhile, even the leading developed countries have considerably different steelmaking patterns (see table 2).

Speaking about the steelmaking pattern, one should also keep in mind the crucial ratio of domestic consumption over exports of metal, as well as rational economic justification of metal exports. It is extremely hard to calculate the precise portion of exports in the total metal output in Ukraine at this point of time, though authoritative sources mention the figure of 70 to 80% of the total output. At the same time, Ukrainian exports have only a few destination points. For instance, Asian countries and the CIS consumed 66% of the total metal exports coming from Ukraine in 1998, while Ukrainian exporters have no other way but sell cheap ordinary metal products, notably semi-finished steel and reinforcing bars. Since the market is oversupplied with these products, global prices are below production costs. Precisely this pattern differs Ukrainian metalmaking from global metallurgy and even from Japan, the largest world exporter with net exports coming to 15% (aggregate exports of 22% and aggregate imports of 7%).

This situation mainly originates from protectionism employed by the leading importing countries. About as important is the fact that Ukraine manufactures metal with few or no special properties. Ukrainian mills make a small portion of low-alloy and alloy steel, are in shortage of the required secondary steel treatment facilities, make insufficient volumes of metal with fixed contents of main chemical elements and inclusions, etc. This situation has it obvious causes.

There are no precise figures on deterioration of main steelmaking equipment, though one can be confident that these figures are not much different from the industry’s average depreciation of 56%. Notably, 87% of open-hearth furnaces, 26% of BOFs, and some 80% of the functioning EAFs have already outran their standard life spans. For example, BOF shops of Petrovsky Iron and Steel Works and Krivorozhstal were phased in back in 1956 and 1965 respectively. The situation with open-hearth shops is even worse, namely open-hearth divisions of Donetsk Metallurgical Works were put into operation in 1945-1951, of Azovstal in 1945-1957, of Makeyevka Iron and Steel Works in 1948-1953, and of Kommunar Iron and Steel Works in 1952-1957. That is why swift renewal of main productive assets should be the indispensable top priority on the way to lower material, fuel, power expenditures, and labor inputs, as well as to proper quality of metal products and pollution control.

Ukrainian metallurgical mills consume more raw materials and fuel compared to mills in the leading metalmaking countries owing to a number of objective and subjective reasons, notably lack of the necessary control systems over feeding of raw materials, fuel, power, and charge materials; application of overblown heat; shortage and irregular supplies of metal scrap; inconsistencies among excessive steelmaking capacities and steel outputs; uneven working schedules; poor quality of lime; deficient furnace lining, etc. However, no matter what the source of these reasons is, transition to competitive products should be undoubtedly accompanied with fundamental changes.

The pattern of steel products features low portion of steel with high quality and nice consumer properties. For instance, 15.2% of the total bars produced, 11.5% of skelp, and 15.4% of the total Ukrainian-made wire rod are consumed domestically. Out of the 51% of metal employed to make sheet steel, some 16.4% are applied to make strips, 23.1% to make plates, and only 7.7% to cold-roll sheets. During the 11 months of 1999, billets accounted for some 23.33% of the total metal exports from Ukraine, various sheets and plates made up 17.03%, rebars 10.64%, and wire rods contributed 5.37% to exports, while rolled low-alloy and alloy steels accounted for only some 2.21%.

Table 1. Steelmaking pattern in the world (%)

Percentage of steel made in

Open-hearth furnaces

Basic oxygen furnaces

Electric arc furnaces

1980

24

54

22

1990

16

56

28

1995

7

60

33

2000 (preliminary estimate)

4

58

38

2010 (preliminary estimate)

1

49

50

Table 2. Steel production in the developed countries (%)

Percentage of steel made in

Basic oxygen furnaces

Electric arc furnaces

Germany

76

24

Japan

67

33

USA

61

39

When it comes to ferroalloys, steelworks receive sufficient volumes of Ukrainian-made ferromanganese and ferrosilicon and that is about all. Moreover, despite the abundance of manganese ore deposits and excessive ore-processing capacities in Ukraine, phosphorus contents in supplied ferromanganese have lately skyrocketed due to a number of reasons. Frequently, metallurgical mills have to use ferromanganese with excessive phosphorus contents, thus crippling the opportunities to make high-quality steel.

The existing ironmaking and steelmaking technologies affect the environment within metallurgical shops. Though steelmaking does not cause too much pollution, tighter environmental and pollution control rules, which are inevitable as Ukraine strives to become part of the European community, will heavily hit upon most metallurgical mills pushing some of them on the verge of complete shutdown. Some 21 to 32 kilograms of dust are emitted with waste gases per tonne of steel made in BOFs and 6 to 9 kg of dust are emitted per tonne of EAF steel. The functioning gas-treating units reduce dust contents down to the standard level of 100 milligrams per cubic meter of gas. However, a number of countries, notably Sweden, have lowered dust contents to 10 mg per cubic m for BOF steelmaking and to 2 mg per cubic m for EAFs. Execution of such a tough standard requires huge capital investments coming to 12% of steelmaking costs.

It is worth spotlighting that Ukrainian mills allocate the amount equaling to less than 3 to 4% of production costs on technical re-equipment. This is much less than in the developed metalmaking countries. Metallurgy has obtained only about 8% of the aggregate foreign investments in the Ukrainian economy, which clearly contradicts the importance of this industry in Ukraine.

Prior to the beginning of the 1990s, Ukrainian scientists and steelmaking engineers were rightfully proud of their extensive participation in development and application of technical and technological breakthroughs. In recent years the ill-famous economic hardships have slashed the amount and the scope of new research and development efforts. The pace of new technologies’ application was rather poor even back in the past years and has lately lowered some more. Therefore, new technologies have a negligible influence on the quality and production cost of steel products.

Thus, the most acute general steelmaking problems embrace high consumption of materials and energy; poor technological level and utilization of quite a few steelmaking facilities beyond their normal service life; unacceptable pollution control including pollution of the working-space environment; deficient pattern of steel production; delays in introduction of internationally-accepted advanced technologies, equipment, and control devices. However, despite all the afflictions, ferrous metallurgy and steelmaking as its integral component lead the way in the Ukrainian economy accounting for 25% of manufacturing outputs and yielding up to 40% of export revenues. Therefore, the authors of this article believe that Ukraine will remain something of a big "metallurgical mill" of Europe in the foreseeable future. The Ukraine’s advantages comprise rich mineral inventories, notably iron ores, traditionally superior technical education, excellent invention skills of medium and top metallurgical workers, branched network of special higher education institutions, etc. Besides, small wages and salaries put less pressure on production costs and Ukraine has milder pollution control requirements with respect to both the atmosphere and water resources. Moreover, Ukraine has an advantageous location between Europe and Asia.

The authors of this article believe that upgrade and further development of Ukrainian steelmaking should be conducted on the basis of the following main points, proven with international experience and modern practice of domestic metallurgical mills.

Steelmaking pattern is the first issue to be dealt with. In general, the BOF processes suit the blast-furnace ironmaking well, just like direct reduction of iron ore matches the EAF processes. Both tandems have their pros and cons related to availability and reserves of feedstock, type and consumption of fuel and power, and impact on the environment.

Forecasts made for the 21st century insist that the bulk of global steel will be made in combination of blast-furnace processes with BOF steelmaking, unless, of course, people come up with new revolutionary super-cost-efficient steelmaking technologies.

It seems that advocates of the triumphant progress of electric arc furnaces make an unintentional mistake commenting only the advantages of this process and neglecting the drawbacks. At the same time, there are perhaps no grounds to hope that these drawbacks will be more or less easily surmounted in the future.

Besides to the traditional deficiencies, such as noise and need in considerable resources of cheap electric power, application of EAFs has much weightier disadvantages. The authors of this article view the major faults in failure of the EAF process to remove such detrimental inclusions as copper, tin, bismuth, antimony, arsenic, nickel, chromium, molybdenum, and cobalt introduced with metal scrap. Besides, for a long time to come, Ukrainian EAFs will have to consume furnace charge with large contents of metal scrap (some 1,020 kg per tonne of steel) compared to the BOF process that consumes roughly 230 kg of scrap per tonne of steel. Introduction of continuous casting and other metal-saving measures reduces the share of heavy scrap, though driving up the portion of old scrap that naturally has poorer quality and features the traditionally volatile prices. Therefore, when trying to assess the prospects of EAF steelmaking in Ukraine, one should consider firstly all these factors, as well as the large difference between supply and cost of electric power in Ukraine and in the USA, Western Europe, and Russia. Without considering mini-mills with their dubious justification in Ukraine, one should agree with A. Morozov, one of the most consistent apologists of EAF steelmaking, who believes that electric arc furnaces are mostly applicable in manufacture of long products, such as bars. Moreover, this conclusion is not true for all the types of long products, because doubled nitrogen contents compared to BOF steel further inflict the product mix. Certain leading western analysts also share this point of view mentioning that the BOF process will dominate in foreign integrated mills in the near future, while EAFs will be the backbone of steelmaking in mini-mills.

This drives to a conclusion that BOF steelmaking will be the principal method for Ukraine. According to our calculations, the BOF process will account for 70% of the total steel output in Ukraine in the coming decade. Therefore, development and perfection of this method is of paramount importance.

Open-hearth steelmaking will have to stagger on for a rather lengthy period of time, at least at the metallurgical mills that have no BOF shops, e.g. in Zaporozhstal, Kommunar Iron and Steel Works, Makeyevka Iron and Steel Works, and K. Liebknecht Metallurgical Works. In 1999 these mills produced approximately 7,850,000 t of steel. This figure is unlikely to go down in the near future, unless these companies face a closedown, which seems improbable for a number of reasons, predominantly the social ones.

We think that the notion of upgrading open-hearth shops via replacement of open-hearth furnaces with BOFs (this idea appeared back in the Soviet times) has way too many flaws and is technically impossible. Besides, this upgrade requires about as much outlays as construction of a brand-new Greenfield steel mill. The well-known idea of the Scientific Research Institute for Metallurgy to replace open-hearth furnaces with direct steelmaking facilities has its specific design requirements, which can be implemented only in Ilyich Iron and Steel Works, because this mill has a huge workshop building with adjacent space that can possible give room to continuous casters. Otherwise, i.e. without construction of continuous casters, this reconstruction has no sense.

As long as BOF steelmaking will be the principal method in Ukraine for a certain period of time, there is a crucial need in assessing the state of the available technologies and equipment to track the main ways for progress of this method. Some 5 to 10 year ago the official sources mentioned that technical level of Ukrainian BOF steelmaking generally rivaled the best similar foreign technologies, save for a couple of individual cases. However, at this point of time, this conclusion seems to be wrong and nonproductive.

The point is that Ukrainian BOF shops lack quite a few essential resource-saving and pollution-control elements that are widely applied in foreign metallurgical mills, namely:

application of a wide range of process control devices, e.g. temperature-taking and metal-testing probes that do not require cessation of blasting or vessel’s turndown, steel oxidization sensors, devices to measure chemical composition of slag, devices for indirect control of production process and metal bath, notably ultrasonic equipment, tongue-radiance and vibration measuring devices, etc.;

application of precise weighing tools to take weight of metal charge, alloying agents, and molten steel;

dynamic process control systems;

slag removal when molten steel is poured into ladle, and application of covering blankets;

recycling of emitted waste gases, notably recovery of CO and reclamation of dust back to the BOF;

introduction of various types of combined blowing;

slag-free steelmaking;

wide use of periclase carbide refractory materials, application of gunning in other processes, for instance blowing of slag after molten steel run off in order to boost the lining’s service life to some 8,000-10,000 smelting operations;

carrying of molten iron in stirring ladles.

Ukrainian BOF shops are also inferior to similar foreign machinery as regards out-of-furnace steel treatment equipment, mainly vacuum degassers and ladle furnaces, and as regards cost-efficient secondary steelmaking.

Ukrainian companies continuous-cast not more than 36% of the total BOF steel. In 1999 the portion of continuous-cast steel in the total steel output increased to 18.7% against 8.3% back in 1990, though this growth mainly sprang from the overall reduction in steel output from 50 million t to 27.1 million t. At the moment, the installed continuous casters account for roughly 19.9% of the total steel-casting capacities. At the same time, it was precisely the widespread use of continuous casters that boosted steel outputs in the world (continuous casting contributed 75% to the growth in production), lowered power consumption, and enhanced steel quality.

Speaking about the Ukrainian way of continuous casting, domestic metallurgical mills yield to the scope of this technology’s application and to the technical standard of the process. Ukrainian steelmakers make little or no use of steel protection against secondary oxidation, dry lining for tundishes, automatic casting control, electromagnetic agitation devices, etc.

Fully acknowledging importance and urgency of casting technologies to make thin slabs, 40-60 mm, and 1-5-mm-thick blank sheet steel, it is also worth highlighting the following points. US company Nucor has worked out and applied a thin-slab technology that benefits from such advantages as low initial outlay and little power consumption. This technology will become the core of EAF steelmaking mini-mills. All the other known methods of thin-slab making, including the ones that try to make use of electric arc furnaces, are still being checked and tested, have an extremely vague range of possible use, and almost no industrial application ideas. As regards equipment making 1-5-mm-thick blank sheets, foreign experts believe that this machinery can only be applied in production of corrosion-resistant steels, in pressure shaping of low-tech alloys, and in execution of other petty orders, i.e. beyond large integrated mills.

Only renewal of productive assets, together with upgrade or fundamental improvement of technologies employed, makes it possible to make up the lag in major steelmaking methods, e.g. BOF steelmaking, secondary steel treatment, and continuous casting.

Table 3. Estimated steel outputs in Ukraine

Steel output

Including made in:

Basic oxygen furnaces

Open-hearth furnaces

Electric arc furnaces

‘000,000 tonnes

% of the total

‘000,000 tonnes

% of the total

‘000,000 tonnes

% of the total

‘000,000 tonnes

% of the total

2005

23.5

15.87

67.5

5.06

21.5

2.58

11.0

10.2

43.4

2010

23.5

17.0

72.0

4.0

17.0

2.58

11.0

18.94

80.5

The international experience clearly proves that there are no other alternatives but technical re-equipment, i.e. upgrade, reconstruction, or, what is the most advisable, new capital construction. Only renewal of productive assets, together with upgrade or fundamental improvement of technologies employed, makes it possible to make up the lag in major steelmaking methods, e.g. BOF steelmaking, secondary steel treatment, and continuous casting. The international experience clearly proves that there are no other alternatives but technical re-equipment, i.e. upgrade, reconstruction, or, what is the most advisable, new capital construction.

To improve the situation in metallurgy, the Verkhovna Rada (Supreme Council) gave its approval to the "National program for development of mining and metallurgical complex of Ukraine". The program aims at defining the main directions, ways, and methods of balancing up development of mining and metalmaking in view of the current economic situation in the country and the industry, situations on domestic and foreign markets, satisfaction of domestic demands for iron and steel, launching of the world market with competitive metal products, etc. Table 3 contains production figures stipulated for the short run in this act.

It is scheduled to build one basic oxygen furnace in Dzerzhinsky Iron and Steel Works, one steelmaking furnace in Dneprospetsstal mill, six continuous shape casters in Krivorozhstal, two continuous shape casters apiece in Donetsk Metallurgical works and Yenakievo Iron and Steel Works, and two continuous slab casters in Dzerzhinsky Iron and Steel Works. In addition, it is planned to phase out a number of open-hearth shops after 2005.

To fundamentally enhance the quality of castings and finished rolled steel, the program provides for construction of 9 ladle metallurgy furnaces and 3 vacuum degassers by 2010, as well as for redesign of the vacuum degasser in Dneprospetsstal mill. It is planned to make 2.58 million t of specialty steels and alloys. In order to back quality, profitability, resource efficiency, and competitiveness, it is also stipulated to phase in powerful 120-tonne electric arc furnaces with partial mothballing of small furnaces. The new furnaces will be accompanied with the mentioned ladle furnaces, vacuum degassers, and continuous casters.

Owing to a number of wonderful technical advantages and the lowest possible payback periods, continuous casting should become the number one priority for technical re-equipment of steel-casting facilities. No one seems to actually doubt this point. The outrageously low pace of continuous casters’ introduction at Ukrainian metallurgical mills bears out that local mills lack money rather than underestimate the importance of this process. Meanwhile, the international practice clearly shows that the traditional way of continuous casting saves as much as 150 kg of steel, up to 3 kg of refractory materials, and 65 kg of reference fuel per tonne of rolled steel. The advanced continuous casting technologies, e.g. hot placement of castings into heating furnaces of rolling mill and direct continuous casting and rolling, save 30 to 40% of molten steel and 15 to 20% of power compared to the simple mold casting. Except for a couple of special products, continuous casting usually yields a huge improvement of macrostructure, surface condition, and, finally, enhances physical and mechanical properties of steel products.

If one tries to explain the staggering tempos of continuous casters’ introduction with the traditional skepticism as regards information coming from foreign countries, he is proved wrong by the recent experience of Ilyich Iron and Steel Works that has partially re-equipped the BOF shop with continuous slab casters. This integrated mill reports that application of continuous casters has lowered the aggregate material, power, and fuel costs to 67% of the total production cost of sheet steel compared to 86% of the total back when mold-cast semi-finished steel was rolled.

When upgrading electric arc furnaces, it is worth targeting efforts at application of direct-current EAFs, scrap preheating with outer (non-electric) heat sources, slag frothing, oxidation reduction of molten metal in furnace, controlled electric arc for uniform scrap melting and prevention of hot and cold spots on the lining, and recycling of waste gases.

Specific steps aimed at modernization and enhancement of BOF steelmaking should eliminate the mentioned deficiencies typical to the contemporary Ukrainian metalmaking. At the same time, much efforts should be concentrated at creation of applicable technologies that would boost the portion of metal scrap in furnace charge, i.e. fight against the main disadvantage of BOFs relating to few opportunities to use metal scrap, which costs only 50 to 70% as much as iron. VNIIVtorchermet scientific research institute and other institutions have calculated that replacement of iron with metal scrap in steelmaking saves 108 kWh of electric power per tonne of steel, 95 cubic meters of oxygen, 78 cubic m of compressed air, 79 cubic m of water, 175 cubic m of natural gas, 800 kg of coal, 400 kg of timber, 1.2 kg of explosives per tonne of steel, etc.

Apparently, activities to improve BOF steelmaking should seek highly automatic standardized and reproductive mode of BOF operations and should aim at lowering of the number of production personnel to the absolute minimum. At the same time, save for a few specific cases, basic oxygen furnaces should turn into melting facilities and decarbonizers taking advantage of various modern technologies to manufacture semi-finished steel. These semis should completely meet the main requirements of out-of-furnace steel treatment as regards adjustment of chemical properties and temperature of molten steel and all the other properties related to serviceability and long service life of structures, machinery, and mechanisms.

On the other hand, development and application of new BOF processes should become a significant direction for further progress of BOF steelmaking. A good example is the Ukrainian technology of BOF steelmaking with outer effects, including superposition of electric potential on molten steel or making use of external magnetic fields. This can boost enthalpy of molten steel and make steel more purified from inclusions at extraordinarily low power consumption and investment. Secondly, this technology meets the standardization task, at the same time improving steel preparedness to out-of-furnace treatment and slashing the time of secondary steel treatment. At last but not least, application of outer effects assists pollution control.

Oxygen blowing of bathes in acid-lined furnaces is yet another worthwhile and promising BOF project. Lab tests and trials at Petrovsky Metallurgical Works (the duplex process of "acid-lined BOF – traditionally lined BOF") have revealed that application of acid silica refractory lining lowers consumption of basic magnesia refractory materials, sharply cuts consumption of molten iron, lime, and oxygen, as well as improves gas contents in metal and enhances the scope and the anisotropy of mechanical properties.

The Ukrainian scientists have quite a few other technological ideas that excel foreign technologies, e.g. application of advanced high-frequency measuring devices in steelmaking (produced as a result of conversion in the defense industry); refining, micro-alloying, and modification of molten iron and steel in electric arcs, plasma, etc.

Since quality of metal products is one of the keys to successful competition in market economy, out-of-furnace treatment is a must that should become the second priority objective for steelmakers after continuous casting. The main directions for progress of secondary steel treatment are as follows:

widespread use of multifunctional units for out-of-furnace treatment and stabilization of chemical properties that meet the current and the future tasks and are equipped with power-saving heating systems, efficient control systems, reliable gas cleanup systems, etc.;

making justified use of vacuum degassing in the ladle;

creation and application of combined out-of-furnace processes to thoroughly remove sulfur, phosphorus, nitrogen, and oxygen via vacuum-slag finishing, reduction argon-slag refining, oxidizing strain, etc.

The objectives of continuous casting should embrace promotion of widespread use of this technology including via construction of the necessary facilities in the main steelmaking shops (notably, BOF shops) or nearby, as well as speeding up of the casting rate and enhancement of productivity; equipping of continuous casters with the necessary devices and systems to enhance quality of continuous-cast steel including electromagnetic agitation devices, condition monitoring systems, and process and product testing devices; achievement of the necessary process control automation; precision of modules’ placement relative to the technological axis; enhancement of the main components’ and gears’ durability; lowering of water consumption via air-and-water mold cooling, etc.

Finally, long-term advanced positions in metalmaking and steelmaking urge for a well-doing and flexible research and development infrastructure. The once-strong scientific and technical potential of Ukrainian metalmaking, which was capable of tackling the current and the future tasks of the industry and of individual metallurgical mills, has weakened and keeps on diminishing. Science has run out of demand because metalmakers have found themselves in a harsh financial situation and lack the necessary centralized financial backup from the state budget. Therefore, to modernize and upgrade metalmaking, the authorities have to pursue a policy of retaining the most experienced and skilled professional scientists and research equipment of scientific research institutions, while firing the unnecessary burden of researchers that do nothing. Keeping in mind the known global trend towards smaller allocations on metallurgical science, one should understand that even the slashed foreign investments in metallurgical machinery and technologies greatly surpass the Ukrainian investments in this field.

Commentary

Vladimir TERESHCHENKO, chief executive officer with the Ukrainian Association of Ferrous Metallurgical Enterprises

It is beyond doubt that Ukraine is predestined to well-developed metalmaking and machine building owing to the country’s extensive mineral inventories of iron ore, manganese ore, coking coals, and developed power-generation system.

To promote high-quality metalmaking, it is highly important to manufacture metal using iron ore, thus reducing contents of impurities and inclusions, retaining natural properties of metal, and scoring considerable cost-efficiency. Therefore, steelmaking should develop accordingly to the demands of machine-building companies and construction firms that are the traditional large-scale consumers of steel.

Unfortunately, lack of favorable investment climate in the Ukrainian industry discourages investments in metalmaking. Thus, metallurgical mills, which suffered losses and worked beyond or close to the breakeven points until recently, now have to finance all the reconstruction projects on their own using their scarce profits.

The Association of Ferrous Metallurgical Enterprises views its priority task in assisting metallurgical mills to legally settle these issues, because execution of the national program for development of mining and metalmaking is the key to lower production costs and power consumption, as well as to supplies of high-quality metal to domestic consumers in Ukraine.

the Metal

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