The article presents the current possibilities for the utilization of blast-furnace and steelmaking slag in the realities of the Polish economy. Particular consideration is given to the legislation applicable to this area and to the physical and chemical requirements imposed on this material. Some aspects of environmental protection are described, and selected indicators are given, which must be met by this material to be used in various fields, such as road construction or cement production. Economical factors that are crucial to perceiving the slag as a standard valuable metallurgical product is also taken into consideration in the analysis.Mogućnost uporabe metalurške troske u uvjetima ekonomije Poljske. 
Članak prikazuje sadašnjemogućnosti uporabe visokopećne i čelične troske u ekonomiji. Posebna pozornost pridaje se zakonodavstvu iztog područja i zahtjevanim fizikalno-kemijskim svojstvima materijala. Opisani su neki oblici zaštite okoliša i izdvojeni pokazatelji koje je neophodno poznavati da bi se navedeni materijal mogao primjenjivati u različitim područjima, kao što su cestogradnja ili proizvodnja cementa. Također su analizirani ekonomski čimbenici presudni za poimanje troske kao vrijednog metalurškog proizvoda

C. Kolmasiak

R. Prusak

Z. Skuza

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Z. SKUZA, C. KOLMASIAK, R. PRUSAKPOSSIBILITIES FOR THE UTILIZATIONOF METALLURGICAL SLAGIN THE CONDITIONS OF THE POLISH ECONOMYReceived – Prispjelo: 2008-01-02Accepted – Prihva}eno: 2008-11-15Review paper – Pregledni radINTRODUCTIONThe changes that have been occurring over the lastperiod of a dozen or so years as a result of ongoing sys-tem transformation and the process of Poland’s integra-tion with the European Communities, have been partic-ularly observable in iron and steel metallurgy. The ad-justment to the market economy rules and the require-ments imposed by the European Union have compelledmany enterprises to implement far-reaching changes oforganizational, technological, ownership, and economicnature, among other things. Those changes, in thesphere of iron and steel metallurgy, have been and arestill being carried out based on restructuringprogrammes being constantly updated by the Govern-ment of the Republic of Poland. In these programmes,the environmental protection issue has been one of thebasic tasks to be carried out so that the impact of themetallurgical industry on the environment be minimizedas far as possible. The ecological aspect of the restruc-turing process has been, on the one hand, the result of in-tentional pro-ecological activities and, on the otherhand, the consequence of a number of other processesoccurring in recent years in the Polish iron and steel met-allurgy. The most important of them include the perma-nent closure of, most often technologically obsolete,metallurgical installations (lines, departments, iron-works and steelworks), or the implementation of newtechnical and technological solutions.The predominating types of waste forming in ironand steel metallurgy are: metallurgical slag, scale, dustand sludge from waste gas purification, and meltingloss. In Poland, the utilization of metallurgical waste iscurrently dealt with, in a majority of cases, by special-ized companies. In other countries, notably in WesternEurope and in the USA, ironworks treat part of theirwaste (e.g. slag) as a full-value product 1 – 4. As sometypes of “waste” are included in the general economicaccounting of a metallurgical enterprise, this approachforces changes in the production system and creates theneed to treat this "waste" as a full-value product equallywith the other elements of the process output vector.LEGISLATIONThe Polish environmental protection legislation isbased on three basic acts and related implementing regu-lations. These include: the Act – Environmental law (of27 April, 2001); the Act – Water law (of 19 July, 2001);and the Act on Waste (of 27 April, 2001). Contrary togeneral opinion, the Polish metallurgical industry, andMETALURGIJA 48 (2009) 2, 125-128 125The article presents the current possibilities for the utilization of blast-furnace and steelmaking slag in the reali-ties of the Polish economy. Particular consideration is given to the legislation applicable to this area and to thephysical and chemical requirements imposed on this material. Some aspects of environmental protection aredescribed, and selected indicators are given, which must be met by this material to be used in various fields,such as road construction or cement production. Economical factors that are crucial to perceiving the slag as astandard valuable metallurgical product is also taken into consideration in the analysis.Key words: blast-furnace slag, steelwork slag, utilizationMogu}nost uporabe metalur{ke troske u uvjetima ekonomije Poljske. ^lanak prikazuje sada{njemogu}nosti uporabe visokope}ne i ~eli~ne troske u ekonomiji. Posebna pozornost pridaje se zakonodavstvu iztog podru~ja i zahtjevanim fizikalno-kemijskim svojstvima materijala. Opisani su neki oblici za{tite okoli{a iizdvojeni pokazatelji koje je neophodno poznavati da bi se navedeni materijal mogao primjenjivati u razli~itimpodru~jima, kao {to su cestogradnja ili proizvodnja cementa. Tako|er su analizirani ekonomski ~imbenici pre-sudni za poimanje troske kao vrijednog metalur{kog proizvoda.Klju~ne rije~i: visokope}na troska, ~eli~anska troska, uporabaISSN 0543-5846METABK 48(2) 125-128 (2009)UDC – UDK 669.1:691:628.477=111Z. Skuza, C. Kolmasiak, R. Prusak. Faculty of Process&Material engi-neering and Appleid Physics, Czestochowa University of Technology,Czestochowa, Polandso iron and steel metallurgy, does not belong to those in-dustries, where the largest amounts of waste are gener-ated (with 6,3 % of the overall amount of waste gener-ated 5). However, ironworks and steel mills use instal-lations in their manufacturing process, whose function-ing, due to the type and scale of their environmental im-pact, require the so called Integrated Permit to be ob-tained. This is granted for a period no longer than 10years, and once every 5 years its review should also bemade by the issuing authority. The Permit specifies thefollowing, among other things: the conditions and quan-tities of emissions of gases or dust; the conditions of wa-ter intake under provisions laid down in the Act – Waterlaw; the permissible noise level; the conditions to be metby discharged waste water; the conditions of generationand the methods of handling the waste under provisionslaid down in the Act on Waste; and requirements for theBest Available Techniques (BAT) for installations cov-ered by the Permit. The above-mentioned legal mea-sures are already an element of the EU legislation settingthe directions of the ecological policy, in which the utili-zation of waste plays an important role.The Act on Waste provides for the implementationof a new system for handling any types of waste. Thisprocedure should be followed in several successivesteps: the prevention of waste formation, the selection ofwaste and its economic utilization as a substitute forraw-materials; waste disposal; storage, as an element ofwaste disposal (e.g. as a floor in a mine); landfill deposi-tion. The Act in question has also obliged competent au-thorities to draw up a National Waste Management Planfor the years 2002 - 2014, in which the waste handlingrules would provide a basis for the formulation oflong-term tasks. Such tasks are necessary for carryingout the objectives set in the State’s ecological policygeared towards achieving EU standards.THE UTILIZATIONOF METALLURGICAL SLAGIn the overall waste forming in metallurgical pro-cesses, blast-furnace slag and steelmaking slag make upthe largest amounts deposited. Their quantity is closelyrelated with the production volume of pig iron and crudeiron. In last five years (2003 – 2007) level of blast fur-nace slag production was 4,4 – 6,4 Mt in Poland and670,1 – 946,3 Mt overall in the world. In 2007 polishproduction of pig iron was about 5 % of EU production(27 countries) and 0,61 % of world production 1. If wetake on to assumption that there is about 0,25 Mt of slagon 1 Mt of pig iron (0,15 – 0,35 Mt, for exampleDeutschland 0,24 kg 4,5) we have 1,45 Mt of blast fur-nace slag in Poland, in EU 29,2 Mt and in the world236,6 Mt. Similarly in Poland level of crude steel pro-duction in 2003 – 2007 was 8,3 – 10,6 Mt and in theworld 969,7 – 1344,3 Mt. Polish production was about5 % of EU production and 0,79 % of overall world pro-duction. Last year in Poland production in bottom oxy-gen furnace was 58 % and in electric arc furnace 42 %(analogically EU – 59,6 %/40,25 %, and world66,35 %/31,2 %) 1. Based on literature for statisticalpurposes 4, 5 on every 1 t of steel we have 0,1 t of slag(both electric and oxygen process, including secondarymetallurgy) – this means that in 2007 in Poland weregenerated 1 Mt of slag (EU – 21 Mt, world – 134 Mt).The increasing world's demand for metallurgicalproducts is thus the cause of formation of an increasingvolume of slag, which forces searching for various met-hods of its utilization. Presently, 100 % of blast-furnaceslag and approx. 75 % of steelmaking slag are utilized3 83 % of waste from steel industry were utylized inPoland in 2007 2). Due to their physicochemical prop-erties, slag materials could have wide application in ce-ment production and in construction.In the case of cement production, the slag is used asone of the basic additives to enhance the cement proper-ties (e.g. to increase strength and resistance to chemicalcorrosion, and to reduce gas and liquid permeability bythe cement pastes of mortars and concretes). In cementplants, chiefly granulated blast-furnace slag finds appli-cation, where it is used in the manufacturing process inquantities depending on the type of cement being manu-factured (even up to 60 %). As indicated by publiclyavailable data 2, 6 related to the production of pig ironand cement, the volume of generated blast-furnace slagis lesser by several times than its demand. Thus, it can bestated that, as a rule, the total quantity of blast-furnaceslag forming in current iron production is wholly uti-lized. It should be added, however, that the estimatedsize of demand concerns the slag in the form of granu-late of specified chemical composition, as required bycement plants. In accordance with the standardEN-197-1, granulated blast-furnace slag to be used forcement production must meet the following quality re-quirements: a minimum vitreous phase content of 67 %;and a minimum (CaO+MgO)/SiO2 ratio of 1. In prac-tice, for technological reasons, the SiO2/(Al2O3+Fe2O3)ratio and the Al2O3/Fe2O3 ratio, or so called hydraulicproperties, expressed by the relationship(CaO+MgO+Al2O3)/SiO2, are also specified, Table 1. Inaddition, blast-furnace slag to be utilized in the cementindustry should contain the least possible contents ofsuch elements, as sodium, potassium, chlorine, chro-mium, as well as heavy metals and alkalis.Research work on steelmaking slag is underway,which is aimed at increasing the potential of its utiliza-tion. Due to the fact that the mass fraction of Bessemerslag accounts for approx. 70 % of the overall mass ofsteelmaking slag generated, a decided majority of re-search works focus on increasing the potential of its fur-ther utilization 3. This type of slag, together with theslag forming in the smelting of carbon steels in electric126 METALURGIJA 48 (2009) 2, 125-128SKUZA Z. et al.: POSSIBILITIES FOR THE UTILIZATION OF METALLURGICAL SLAG IN THE CONDITIONS...arc furnaces, are now largely utilized (the most difficultfor utilization is the slag forming in the production ofstainless steels, due to the high chromium and nickelcontents). In Europe, of the whole volume ofsteelmaking slag, nearly half, accordly to data from2004 – 3, finds application in construction (the con-struction of roads, dams, levees, and as building mate-rial additives), and a further 17 %, being deposited ontemporary landfills, might be utilized in the future, e.g.in road construction. Particularly prospective in the Pol-ish conditions seems to be the utilization of slag in theconstruction and upgrading of roads and motorways(e.g. road subsoil reinforcement, substructure dewate-ring, making binding layers and wearing courses, em-bankments, etc.).Table 1. Values of technological coefficients of blast-furnace slag for present (october 2007) acti-vities of cement plant (RCM Poland group)Slag examplesSiOAl O Fe O22 3 2 3Al OFe O2 32 3Slag I 4,1 5,1Slag II 2,5 8,0Slag III 4,3 6,8Slag IV 4,3 6,1Slag examplesCaO MgO Al OSiO  2 32CaO MgOSiO2Slag I 1,56 1,35Slag II 1,75 1,41Slag III 1,58 1,37Slag IV 1,49 1,29Preliminary calculations of the road industry’s de-mand for metallurgical slag have been made in thisstudy (the values presented herein have been calculatedbased on data obtained from specific road sections). Thecalculations show that 40000 t slag can be used for theconstruction of one kilometre of motorway, while 3200 t for the upgrading of 1 km of local roads. Simi-larly as in the case of cement production, slag used inconstruction must meet a number of physicochemicalrequirements. Those requirements, however, are not speci-fied by the customer who wants to utilize the waste, butare strictly laid down by standards being presently inforce in Poland. Two basic European standards (in ac-cordance with the Directive 89/106/EEC) have alreadybeen applicable to building aggregates for several yearsin Poland, namely PN–EN 13043: 2004 and PN–EN13242: 2004. European standards have redefined manyconcepts in a manner different from that which was usedpreviously, e.g. the division into mineral and artificialaggregates, which was functioning according to thecommon understanding of these materials, has beenabolished. Generally, it can be accepted that the equiva-lent for the former classes are physical requirements,and for the grades – geometrical requirements, whichmeans that the basic of classification is the set of charac-teristics of an aggregate. The substitution of the afore-mentioned European standards for several Polish stan-dards, e.g. PN–B–11115: 1998 or PN–B–23004: 1988has not involved in practice any changes. By the end of2007, there were still no technical specifications refer-ring to the new standards, which would define require-ments for a specific structural layer of a given trafficroute. As a consequence, construction companies arestill bound by criteria being established based on, e.g.,the PN–B–11115 standard of 1998. The purpose andrange of application of a given lot of a building materialhaving the attestation of the State Hygiene Institution isspecified in the so called Manufacturer’s Declaration ofConformity. The statements contained therein should besupported by the complete set of tests required by thestandards. These tests include the determination of: den-sity, foreign matter content, grain size distribution, grainshape, absorbability, freeze resistance, bitumen adher-ence, calcium decomposition, iron decomposition, andwearability. In addition, an aggregate must meet the re-quirements imposed by relevant Regulations of theCouncil of Ministers. In general, the ecological assess-ment of steelmaking or blast-furnace slag aggregates,based on chemical analysis, should state that the roadaggregate made from slag may be used, e.g., as an as-phalt course base, and does not contaminate soil or sur-face water, due to its very low solubility in water solu-tion.The excess of steelmaking slag, whose utilization isnot possible due to various reasons, shall be depositedon dumps. Today the steel plants have to pay 100–400US$ per ton for external treatment 7. This operationentails incurring additional economic costs, part ofwhich could certainly be avoidable, if the depositionprocess included appropriate segregation that would al-low for the diversity of chemical composition, and sophysicochemical properties of the material being depos-ited. Indeed, it happens that a particular type of slagcoming from within the same steelwork, Table 2., andeven from the same heat, exhibits a composition whichis diverse enough to cause problems with slag utilizationin some areas. Another, equally important criterion (be-sides the properties) which is decisive to the use of slagin construction is the economic justification of trans-porting this material beyond some distances.Slag dumps are situated in strictly defined areas, in adecided majority also in one region of Poland (theSilesian province), which largely limits its utilization,e.g., for making the foundation of different types ofroad. Another, equally important criterion (besides theproperties) which is decisive to the use of slag in con-struction is the economic justification of transportingthis material beyond some distances.METALURGIJA 48 (2009) 2, 125-128 127SKUZA Z. et al.: POSSIBILITIES FOR THE UTILIZATION OF METALLURGICAL SLAG IN THE CONDITIONS...SUMMARYAlthough slag has the largest quantitative share inthe overall metallurgical waste, its physicochemicalproperties offer a high potential for its utilization.Blast-furnace slag is already today utilized in 100 % inPoland in the production of cement, and only part of thesteelmaking slag is deposited on dumps. This quantitycould be further reduced, if - following the example ofWestern Europe or the USA - Polish ironworks and steelmills treated the slag not as waste, but as a full-valueproduct. This approach requires the introduction of anumber of changes, e.g. well-thought-out scrap manage-ment aimed at the stabilization of charge conditions;nevertheless, with an appropriate ecological policy ofthe State, such activities should bring about measurableeconomic advantages.However, slag properties are a necessary, but insuffi-cient condition for a given batch of material to be uti-lized, e.g., in road construction. Another very importantcriterion is the economic factor. The cost of transportcontributes significantly to the price of aggregate (above50 km price of aggregate’s transport is twice as much asits price on slug dumps – data from Poland in 2007),which, in the case of steelmaking slag, can limit the po-tential for its use in the construction or upgrading or lo-cal roads or motorways to areas situated in the vicinityof slag dumps.REFERENCES1 www.worldsteel.org – 3.05.082 www.hiph.com.pl – 5.05.20083 Dziarmagowski M.: The process of Bessemer slag reduc-tion in the electric arc furnace, AGH, University Scientific& Teaching Publishing House, Krakow, 20074 Mróz J.: Recycling and Utylization ofwastes in metallurgi-cal aggregats, Czestochowa University of Technology Pu-blishing House, Czestochowa 20065 www.mos.gov.pl – 12.04.2007 National Waste Manage-ment Plan6 www.polskicement.pl – 5.05.20087 Ye G., Burstrom E., Kuhn M., Piret J., Reduction of steel –making slags for recovery of valuable metals and oxide ma-terials, Scandinavian Journal of Metallurgy, 32(2003)1Note: Translation on english language is responsible Mr. C. Grochowina,Poland.128 METALURGIJA 48 (2009) 2, 125-128SKUZA Z. et al.: POSSIBILITIES FOR THE UTILIZATION OF METALLURGICAL SLAG IN THE CONDITIONS...Table 2. Chemical composition of steelmaking slag from analyzed steelworkFetot. FeO SiO2 CaO MgO Al2O3 MnO P2O5 TiO2 Cr2O3 CaO MgO Al OSiO  2 32wt%Slag I 26,86 23,73 9,53 35,57 8,67 2,06 3,82 0,61 0,27 0,70 4,9Slag II 32,10 32,12 13,84 25,52 9,24 3,03 3,5 0,8 0,36 0,90 2,7Slag III 30,09 30,96 14,68 21,71 10,85 3,49 6,5 0,85 0,28 1,26 2,4Slag IV 20,1 19,2 13,2 37,7 5,2 3,3 5,6 0,6 0,38 2,3 3,5Slag V 17,4 17,4 17 36,7 6,5 3,7 6,2 0,85 0,41 1,9 2,7Slag VI 37,22 36,77 8,22 26,8 5,81 2,52 3,91 - - - 4,3Slag VII 37 39,28 9,37 24,4 8,24 1,98 4,87 0,58 0,25 1,51 3,7Comment: The designation was performed with following methods: FeO with titration method with potassium dichromate according to IBL2483 norm.SiO2, CaO, MgO, MnO, Al2O3, P2O5, TiO2, Cr2O3, with the inductively coupled plasma (ICP) technique. S with the method of the combustion analysis inLECO analyser according to IBL2102 norm. Samples for analysis were received by technologist from slag before tapping of slag according to PN – H –04000 norm.

Mogućnost uporabe metalurške troske u uvjetima ekonomije Poljske

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