Registration Dossier
Registration Dossier
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EC number: 266-007-8 | CAS number: 65996-74-9 The oxidized surface of steel produced during reheating, conditioning, hot rolling, and hot forming operations. This substance is usually removed by process waters used for descaling, roll and material cooling, and other purposes. It is subsequently recovered by gravity separation techniques. Composed primarily of high-purity iron oxides. May contain varying amounts of other oxides, elements, and trace compounds.
Density
Administrative data
Link to relevant study record(s)
- Endpoint:
- density
- Type of information:
- other: handbook data
- Adequacy of study:
- supporting study
- Study period:
- not specified
- Reliability:
- 4 (not assignable)
- Rationale for reliability incl. deficiencies:
- data from handbook or collection of data
- Remarks:
- reference is not complete
- Qualifier:
- no guideline followed
- Principles of method if other than guideline:
- not applicable - handbook data
- GLP compliance:
- not specified
- Type of method:
- other: not specified
- Dynamic viscosity of test material:
- not applicable
- Type:
- density
- Density:
- > 4.9 - < 5.2 g/cm³
- Conclusions:
- Density is given in a range between 4.9 and 5.2 g/cm³.
- Endpoint:
- density, other
- Remarks:
- true density, apparent density, packed bulk density
- Type of information:
- other: Data from a publication on the preparation of iron powder from mill scale. A Hosokawa Micron-PT-X powder tester was used to characterise the mill scale sample.
- Adequacy of study:
- supporting study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- test procedure in accordance with national standard methods with acceptable restrictions
- Remarks:
- Data from a publication on the preparation of iron powder from mill scale. A Hosokawa Micron-PT-X powder tester was used to characterise the mill scale sample.
- Principles of method if other than guideline:
- A Hosokawa Micron-PT-X powder tester was used to characterise the mill scale sample. No details provided on the fundamentals of the method.
- GLP compliance:
- not specified
- Specific details on test material used for the study:
- In the publication, the mill scale is described as "mill scale by-product from TATA STEEL". No further details are provided.
- Type:
- other: apparent density
- Density:
- 2.49 g/cm³
- Type:
- other: true density
- Density:
- 5.41 g/cm³
- Type:
- other: packed bulk density
- Density:
- 3.43 g/cm³
- Endpoint:
- density, other
- Remarks:
- bulk density; density
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 2010
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- guideline study without detailed documentation
- Qualifier:
- according to guideline
- Guideline:
- other: EN 1097-3
- Version / remarks:
- The bulk density was determined in analogy to norm EN 1097-3. The density was determined in accordance with the principle of Archimedes.
- Principles of method if other than guideline:
- The bulk density was determined in analogy to norm EN 1097-3. The density was determined in accordance with the principle of Archimedes.
- GLP compliance:
- not specified
- Type of method:
- other: The bulk density was determined in analogy to norm EN 1097-3. The density was determined in accordance with the principle of Archimedes.
- Specific details on test material used for the study:
- Two samples of mill scale have been tested. They are identified in the report as "Black Iron Oxide type A and B"
- Dynamic viscosity of test material:
- not applicable
- Type:
- bulk density
- Density:
- ca. 2.6 g/cm³
- Temp.:
- 20 °C
- Remarks on result:
- other: Test temperature not stated in report. Assumed to be room/ambient temperature.
- Type:
- density
- Density:
- ca. 4.8 g/cm³
- Temp.:
- 20 °C
- Remarks on result:
- other: Test temperature not stated in report. Assumed to be room/ambient temperature.
Referenceopen allclose all
Description of key information
Mill scale occurs as a by-product during the hot processing of a wide variety of steels – plain carbon steels, low alloy steels, high alloy steels etc. which leads to a wide variability in composition between mill scale from different processes or plants. The density is therefore also variable depending on the origin of the mill scale. Two reliable sources have determined the true density of mill scale samples at ca. 4.8 g/cm³ (Merox, 2010), and at ca. 5.4 g/cm³ (Sista et al. 2020). Another, supporting reference (Handbook, 2007) reports a range of density if mill scale of 4.9-5.2 g/cm³. For the sake of reporting a single value - while acknowledging the variability between samples - a relative density of 5.1 g/cm³ is used as the key value for chemical safety assessment.
Key value for chemical safety assessment
- Relative density at 20C:
- 5.1
Additional information
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
