IT201800005627A1 - PROCEDURE FOR OBTAINING ABRASIVE MATERIALS FROM INERT AGGREGATES ARISING FROM METALLURGIC WASTE - Google Patents
PROCEDURE FOR OBTAINING ABRASIVE MATERIALS FROM INERT AGGREGATES ARISING FROM METALLURGIC WASTE Download PDFInfo
- Publication number
- IT201800005627A1 IT201800005627A1 IT102018000005627A IT201800005627A IT201800005627A1 IT 201800005627 A1 IT201800005627 A1 IT 201800005627A1 IT 102018000005627 A IT102018000005627 A IT 102018000005627A IT 201800005627 A IT201800005627 A IT 201800005627A IT 201800005627 A1 IT201800005627 A1 IT 201800005627A1
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- IT
- Italy
- Prior art keywords
- sample
- aggregate
- particles
- inert
- grinding
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 26
- 239000003082 abrasive agent Substances 0.000 title claims description 13
- 239000002699 waste material Substances 0.000 title description 3
- 239000002245 particle Substances 0.000 claims description 15
- 239000002893 slag Substances 0.000 claims description 13
- 239000000463 material Substances 0.000 claims description 9
- 238000007873 sieving Methods 0.000 claims description 9
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 4
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 4
- 230000003247 decreasing effect Effects 0.000 claims description 4
- QDOXWKRWXJOMAK-UHFFFAOYSA-N dichromium trioxide Chemical compound O=[Cr]O[Cr]=O QDOXWKRWXJOMAK-UHFFFAOYSA-N 0.000 claims description 4
- 239000012467 final product Substances 0.000 claims description 3
- 239000000047 product Substances 0.000 claims description 3
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 2
- 229910052681 coesite Inorganic materials 0.000 claims description 2
- 229910052593 corundum Inorganic materials 0.000 claims description 2
- 229910052906 cristobalite Inorganic materials 0.000 claims description 2
- 230000001186 cumulative effect Effects 0.000 claims description 2
- 239000000428 dust Substances 0.000 claims description 2
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 230000000717 retained effect Effects 0.000 claims description 2
- 239000000377 silicon dioxide Substances 0.000 claims description 2
- 235000012239 silicon dioxide Nutrition 0.000 claims description 2
- 229910052682 stishovite Inorganic materials 0.000 claims description 2
- 239000000126 substance Substances 0.000 claims description 2
- 229910052905 tridymite Inorganic materials 0.000 claims description 2
- 238000005406 washing Methods 0.000 claims description 2
- 229910001845 yogo sapphire Inorganic materials 0.000 claims description 2
- 238000001035 drying Methods 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 2
- 238000010891 electric arc Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 235000012241 calcium silicate Nutrition 0.000 description 1
- 239000004568 cement Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C1/00—Ingredients generally applicable to manufacture of glasses, glazes, or vitreous enamels
- C03C1/002—Use of waste materials, e.g. slags
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K3/00—Materials not provided for elsewhere
- C09K3/14—Anti-slip materials; Abrasives
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Polishing Bodies And Polishing Tools (AREA)
Description
PROCEDIMENTO PER OTTENERE MATERIALI ABRASIVI DA AGGREGATI INERTI DERIVANTI DA SCORIE METALLURGICHE PROCEDURE FOR OBTAINING ABRASIVE MATERIALS FROM INERT AGGREGATES ARISING FROM METALLURGIC WASTE
La presente invenzione si riferisce genericamente ad un procedimento per ottenere materiali abrasivi a partire da aggregati inerti derivanti da scorie metallurgiche. Più in particolare, l’invenzione riguarda un procedimento di trasformazione di un aggregato inerte derivante da scorie nere EAF a materiale abrasivo (la sigla EAF è un acronimo di “Electric Arc Furnace” o forno elettrico ad arco, utilizzato in metallurgia per la produzione dell’acciaio a partire dal rottame. The present invention generally refers to a process for obtaining abrasive materials starting from inert aggregates deriving from metallurgical slag. More specifically, the invention relates to a process for transforming an inert aggregate deriving from EAF black slag into abrasive material (the acronym EAF is an acronym for "Electric Arc Furnace" or electric arc furnace, used in metallurgy for the production of steel from scrap.
E’ detta comunemente scoria il prodotto schiumoso solidificato che si deposita superiormente ai bagni di fusione durante la produzione dei metalli; a raffreddamento avvenuto è un agglomerato di massa uniforme e solida (schiuma solidificata) di impurità non volatili del minerale (intese come parti solide non metalliche), costituite prevalentemente da silicati di alluminio e calcio, normali componenti della roccia. Le scorie di minore densità sono allontanate per tracimazione e spesso sono utilizzate come materie prime di produzioni accessorie, tipicamente per la produzione di cementi. The solidified foamy product that is deposited above the melting baths during the production of metals is commonly called slag; after cooling it is an agglomerate of uniform and solid mass (solidified foam) of non-volatile mineral impurities (intended as solid non-metallic parts), consisting mainly of aluminum and calcium silicates, normal components of the rock. The lower density slags are removed by overflow and are often used as raw materials for ancillary productions, typically for the production of cements.
Quindi, secondo la tecnica nota, la maggior parte delle scorie metallurgiche non viene più riutilizzata e concorre all’aumento dell’inquinamento atmosferico. Therefore, according to the known technique, most of the metallurgical waste is no longer reused and contributes to the increase in atmospheric pollution.
Nell’ambito delle esigenze menzionate, quindi, scopo principale della presente invenzione è quello di superare gli inconvenienti della tecnica nota e, in particolare, quello di realizzare un procedimento per ottenere materiali abrasivi a partire da aggregati inerti derivanti da scorie metallurgiche, che consenta di limitare l’inquinamento atmosferico derivante dall’allontanamento delle scorie metallurgiche e dal loro minimo re-impiego nell’attività produttiva. Within the scope of the aforementioned requirements, therefore, the main object of the present invention is to overcome the drawbacks of the known art and, in particular, to provide a process for obtaining abrasive materials starting from inert aggregates deriving from metallurgical slag, which allows to limit atmospheric pollution deriving from the removal of metallurgical slags and their minimum re-use in production.
Altro scopo della presente invenzione è quello di realizzare un procedimento per ottenere materiali abrasivi a partire da aggregati inerti derivanti da scorie metallurgiche in modo efficiente e sicuro e con elevati rendimenti. Another object of the present invention is to provide a process for obtaining abrasive materials starting from inert aggregates deriving from metallurgical slag in an efficient and safe way and with high yields.
Ulteriore scopo della presente invenzione è quello di realizzare un procedimento per ottenere materiali abrasivi a partire da aggregati inerti derivanti da scorie metallurgiche, che presenti un costo di realizzazione basso rispetto alle tecniche note. A further object of the present invention is to provide a process for obtaining abrasive materials starting from inert aggregates deriving from metallurgical slag, which has a low manufacturing cost with respect to known techniques.
Questi ed altri scopi, che saranno maggiormente evidenti nel seguito della trattazione, sono ottenuti secondo l’invenzione mediante un procedimento per ottenere materiali abrasivi a partire da aggregati inerti derivanti da scorie metallurgiche secondo la rivendicazione 1 allegata; ulteriori specifiche tecniche di dettaglio del procedimento sono riportate nelle rivendicazioni dipendenti successive. These and other purposes, which will be more evident in the rest of the discussion, are obtained according to the invention by means of a process for obtaining abrasive materials starting from inert aggregates deriving from metallurgical slag according to the attached claim 1; further detailed technical specifications of the process are reported in the subsequent dependent claims.
Ulteriori caratteristiche e vantaggi della presente invenzione saranno maggiormente evidenti dalla descrizione che segue, riferita ad un esempio di realizzazione preferito, ma non limitativo, del procedimento in questione. Further characteristics and advantages of the present invention will be more evident from the following description, referring to a preferred but not limiting embodiment of the process in question.
Al fine di realizzare il procedimento, che è oggetto della presente invenzione, si parte da un campione di aggregato inerte derivante da scorie metallurgiche, la cui composizione chimica è la seguente: In order to carry out the process, which is the subject of the present invention, we start from a sample of inert aggregate deriving from metallurgical slag, whose chemical composition is the following:
MgO → 5,2% MgO → 5.2%
Al2O3→ 13,3% Al2O3 → 13.3%
SiO2→ 11,8% SiO2 → 11.8%
SO3→ 0,10% SO3 → 0.10%
CaO → 26,2% CaO → 26.2%
TiO2→ 0,80% TiO2 → 0.80%
Cr2O3→ <1% Cr2O3 → <1%
MnO → <1% MnO → <1%
Fe2O3→ 33,4% Fe2O3 → 33.4%
V2O5→ 0,10% V2O5 → 0.10%
Umidità→ percentuale residua. Moisture → residual percentage.
Il procedimento si svolge dapprima macinando il campione di aggregato inerte, per mezzo di un mulino. Nel mulino, l’aggregato inerte entra in una camera anti-polvere da una tramoggia di riempimento e viene alimentato verticalmente tra due dischi; in particolare, un disco di macinazione mobile ruota contro un disco fisso, andando così a macinare il materiale, tramite forze di pressione e di frizione. La distanza fra i dischi di macinazione è regolabile in continuo anche durante la macinazione ed è compresa preferibilmente nell’intervallo 0,1-5 mm. The procedure is carried out first by grinding the sample of inert aggregate, by means of a mill. In the mill, the inert aggregate enters an anti-dust chamber from a filling hopper and is fed vertically between two discs; in particular, a movable grinding disc rotates against a fixed disc, thus grinding the material, by means of pressure and friction forces. The distance between the grinding discs is continuously adjustable even during grinding and is preferably within the 0.1-5 mm range.
La conformazione dei dischi di macinazione permette all’aggregato inerte di essere dapprima sgrossato e poi finemente macinato grazie alla forza centrifuga, che spinge il campione verso la parte esterna dei dischi. L’aggregato processato viene infine raccolto in un apposito contenitore. The conformation of the grinding discs allows the inert aggregate to be first roughed and then finely ground thanks to the centrifugal force, which pushes the sample towards the outside of the discs. The processed aggregate is finally collected in a special container.
Una volta effettuata la macinazione, si passa ad una seconda fase, che prevede un’attività di stacciatura a umido; durante tale fase di stacciatura, le particelle di aggregato macinate vengono isolate in base alla propria dimensione. Once the grinding has been carried out, a second phase is carried out, which involves a wet sieving activity; during this sieving phase, the ground aggregate particles are isolated according to their size.
In particolare, l’attività di stacciatura a umido consiste nel dividere, per mezzo di una serie di stacci, il materiale macinato in numerose classi granulometriche di dimensioni decrescenti. In particular, the wet sieving activity consists in dividing, by means of a series of sieves, the ground material into numerous granulometric classes of decreasing size.
Le dimensioni delle maglie ed il numero di stacci sono scelti in base alla natura del campione ed in base a quanto richiesto in termini di risultato finale. The size of the meshes and the number of sieves are chosen based on the nature of the sample and on the basis of what is required in terms of the final result.
In pratica, il materiale macinato viene versato in un setacciatore a vibrazione meccanica, che presenta una colonna di stacci sovrapposti; la colonna comprende un coperchio ed un recipiente di fondo e, tra il coperchio ed il recipiente di fondo, un certo numero di stacci sovrapposti e disposti dal maggiore verso il minore, in ordine di dimensione decrescente di maglia. In practice, the ground material is poured into a mechanical vibration sieve, which has a column of superimposed sieves; the column comprises a lid and a bottom receptacle and, between the lid and the bottom receptacle, a certain number of superimposed sieves arranged from the largest to the least, in order of decreasing mesh size.
Contestualmente alla vibrazione ed alla setacciatura, la serie di stacci e, quindi, il materiale macinato vengono continuamente soggetti a lavaggio per mezzo di un circuito idrico, così da pulire e lavare il prodotto macinato dalle particelle più fini. At the same time as the vibration and sieving, the series of sieves and, therefore, the ground material are continuously subjected to washing by means of a water circuit, so as to clean and wash the ground product from the finest particles.
La massa delle particelle trattenute sui vari stacci viene rapportata alla massa iniziale del materiale macinato e le percentuali cumulative del materiale passante attraverso ogni staccio sono registrate in forma numerica ed espresse in percentuale rispetto alla massa del campione intero iniziale. The mass of the particles retained on the various sieves is compared to the initial mass of the ground material and the cumulative percentages of the material passing through each sieve are recorded in numerical form and expressed as a percentage with respect to the mass of the initial whole sample.
Infine, sia il campione iniziale che le singole porzioni vagliate e lavate vengono essiccate in una stufa ventilata fino a divenire una massa costante. Finally, both the initial sample and the individual screened and washed portions are dried in a ventilated oven until they become a constant mass.
In pratica, quindi, durante la fase di stacciatura, le particelle vengono isolate in base alla propria dimensione; si ha dunque che al termine del processo il materiale abrasivo è ottenuto (e separato) in diverse particelle di dimensioni granulometriche, quali 800 µm, 750 µm, 700 µm, 650 µm, 600 µm, 550 µm, ecc., fino alla dimensione più piccola di 50 µm. In practice, therefore, during the sieving phase, the particles are isolated according to their size; therefore, at the end of the process the abrasive material is obtained (and separated) into different particles of particle size, such as 800 µm, 750 µm, 700 µm, 650 µm, 600 µm, 550 µm, etc., up to the largest size small of 50 µm.
Indipendentemente dalle dimensioni, le particelle componenti il prodotto finale presentano una forma spigolosa ed atte ad essere impiegate quale abrasivo di grande durezza per le lavorazioni meccaniche. Regardless of the size, the particles making up the final product have an angular shape and are suitable for use as a very hard abrasive for mechanical processing.
Il prodotto finale risulta infatti di elevata durezza, bassissima fragilità e di natura cristallina, per innumerevoli usi, quali l’affilatura, il taglio, ecc. L’utilizzo dell’abrasivo può essere fatto sotto forma di polvere applicata a fogli di carta o tela oppure sinterizzato per formare mole o pietre abrasive. The final product is in fact of high hardness, very low brittleness and crystalline nature, for countless uses, such as sharpening, cutting, etc. The use of the abrasive can be done in the form of powder applied to sheets of paper or canvas or sintered to form abrasive wheels or stones.
Si è così constatato come sia possibile, in modo veloce, semplice e pratico, ottenere un materiale abrasivo avente caratteristiche ottimali a partire da scorie metallurgiche, che, in tal caso, non vengono rottamate, ma possono essere riutilizzate in modo vantaggioso, limitando altresì l’incremento dell’inquinamento atmosferico. It has thus been found that it is possible, in a quick, simple and practical way, to obtain an abrasive material with optimal characteristics starting from metallurgical slag, which, in this case, are not scrapped, but can be reused in an advantageous way, also limiting the 'increase in atmospheric pollution.
Dalla descrizione effettuata risultano chiare le caratteristiche del procedimento per ottenere materiali abrasivi a partire da aggregati inerti derivanti da scorie metallurgiche, che è oggetto della presente invenzione, così come chiari ne risultano i vantaggi. E’ chiaro, infine, che numerose altre varianti possono essere apportate al procedimento in questione, senza per questo uscire dai principi di novità insiti nell’idea inventiva delle rivendicazioni allegate, così come è chiaro che, nella pratica attuazione dell’invenzione, i materiali, le forme e le dimensioni dei dettagli illustrati potranno essere qualsiasi a seconda delle esigenze e gli stessi potranno essere sostituiti con altri tecnicamente equivalenti. From the above description the characteristics of the process for obtaining abrasive materials starting from inert aggregates deriving from metallurgical slag, which is the object of the present invention, are clear, as are the advantages. Finally, it is clear that numerous other variants can be made to the process in question, without thereby departing from the novelty principles inherent in the inventive idea of the attached claims, just as it is clear that, in the practical implementation of the invention, the materials , the shapes and dimensions of the illustrated details may be any according to requirements and the same may be replaced with other technically equivalent ones.
Claims (9)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT102018000005627A IT201800005627A1 (en) | 2018-05-23 | 2018-05-23 | PROCEDURE FOR OBTAINING ABRASIVE MATERIALS FROM INERT AGGREGATES ARISING FROM METALLURGIC WASTE |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT102018000005627A IT201800005627A1 (en) | 2018-05-23 | 2018-05-23 | PROCEDURE FOR OBTAINING ABRASIVE MATERIALS FROM INERT AGGREGATES ARISING FROM METALLURGIC WASTE |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| IT201800005627A1 true IT201800005627A1 (en) | 2019-11-23 |
Family
ID=63244808
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| IT102018000005627A IT201800005627A1 (en) | 2018-05-23 | 2018-05-23 | PROCEDURE FOR OBTAINING ABRASIVE MATERIALS FROM INERT AGGREGATES ARISING FROM METALLURGIC WASTE |
Country Status (1)
| Country | Link |
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| IT (1) | IT201800005627A1 (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0116272A2 (en) * | 1983-01-15 | 1984-08-22 | Krupp-Steag Strahlmittel Gesellschaft mit beschränkter Haftung | Manufacturing process of silicon and iron free blast material for surface treatment |
| US5964911A (en) * | 1998-07-28 | 1999-10-12 | Howard J. Greenwald | Process for making an abrasive composition |
| EP3037560A1 (en) * | 2014-12-22 | 2016-06-29 | Paolo Bevilacqua | Method and apparatus for the valorization of steel slags |
-
2018
- 2018-05-23 IT IT102018000005627A patent/IT201800005627A1/en unknown
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0116272A2 (en) * | 1983-01-15 | 1984-08-22 | Krupp-Steag Strahlmittel Gesellschaft mit beschränkter Haftung | Manufacturing process of silicon and iron free blast material for surface treatment |
| US5964911A (en) * | 1998-07-28 | 1999-10-12 | Howard J. Greenwald | Process for making an abrasive composition |
| EP3037560A1 (en) * | 2014-12-22 | 2016-06-29 | Paolo Bevilacqua | Method and apparatus for the valorization of steel slags |
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