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Aluminosilicate Refractory Ceramic Fibres CAS Number: - EC Number:

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Aluminosilicate Refractory Ceramic Fibres CAS Number: - EC Number: 12.11.2009 COMMENTS AND RESPONSE TO COMMENTS ON ANNEX XV SVHC: PROPOSAL AND JUSTIFICATION Disclaimer: The European Chemicals Agency is not responsible for the content of this document. The Response to Comments table has been prepared by the competent authority of the Member State preparing the proposal for identification of a Substance of Very High Concern. The comments were received during the public consultation of the Annex XV dossier. Substance name: Aluminosilicate Refractory Ceramic Fibres CAS number: - EC number: - Reason of the submission of the Annex XV: CMR General comments No. Date Submitted by (name, Comment Response Organisation/MSCA) 1 20090928 Air Liquide, Company, Since RCF are classified as a Category 2 Statement, no response necessary France carcinogen by the European Commission (EC), specific restrictions are imposed on the handling, use, and disposal of RCF in accordance with multiple Commission Directives (European Directives 69/97/EC). AES fibers have similar thermal properties to RCF, but are exonerated from carcinogenic classification by the EC. The objective of this document is to The intention of the authors was to demonstrate; that RCFs are demonstrate that substitution of RCF related to risks for workers and secondly that these risks are (Refractory Ceramic Fibres), used as avoidable when substitutes are used as insulation material. insulation materials for Steam Methane Reforming Units, by AES (Alkaline Earth Actually, AES (Alkaline Earth Silicate) fibres are not classified as Silicate) does not improve workers safety. carcinogenic. Therefore, substitution gives the opportunity to improve the safety of workers. For details see comment on Steam Methane Reforming below. 2 20091005 Individual, United Kingdom I support the nomination of this chemical to No response necessary the Candidate List, and believe it is important, given its properties, for it to be as strictly controlled as possible. 3 20091005 SELAS-LINDE GmbH, p. 2.1: Alternative Substances The Steam Methane Reforming (SMR) process consists of the Company, Germany two steps1 that are associated with different temperature ranges Generally spoken it doesn't make sense to up to 1100 °C. In addition, insulation material comes into contact discuss the use of AES for high temperature with H2 and CO which leads to decomposition of the material. process applications at all: AES fiber is an insulation material which doesn't have In general there are different bio-soluble fiber products of AES similar thermal properties to RCF as it can (Alkaline Earth Silicate) available on the market. Their permanently be used only at temperatures classification temperature – provided by the product data sheet below 800°C. Installed in furnaces with – comprises from 1000 up to 1300°C (e.g. product known under fluegas temperatures of more than 800°C the trade name Superwool HT 6072). This implies that products (e.g. steam methane reforming - SMR) it will of AES for high-temperature applications up to about 1100- be destroyed soon (shrinkage, 1170°C are suitable for long-time use under “real operating embrittlement, vitification) – apart from the conditions”. Therefore the application temperature of bio-soluble formation of cristoballite. fiber products covers the needed temperature range in the SMR The discussion of advantages or process. disadvantages of AES instead of RCF material regarding improvement of safer The substitution of RCF fibres is regulated in Germany in the work therefore is not decisive. Technical Rule for Hazardous Substance TRGS 619 “Substitute If there should be the demand to use Materials for Aluminium Silicate Wool Products”. Therefore the alternative material instead of RCF for high dossier reflects the approach taken in TRGS 619 (2007)3. With temperature applications it can not be AES regard to thermal insulation in furnace and firing system fiber but brick linings or castable linings. construction (which may include the situation as for SMR) the These alternative lining materials are TRGS 619 recommends appropriate substitutes in Annex 1 possible for SMR applications but their (Descriptive profile for selecting a substitute for aluminium physical properties have to be regarded silicate wool products for thermal insulation in furnace and firing under consideration of the side-effects: due system construction, especially at application temperatures to higher heat storage capacity of castable higher than 900°C in accordance with § 7 paragraph 1, No. 5 or brick linings the units have to be Ordinance on Hazardous Substances). equipped and operated in different ways (additional cooling of coils, slow cooling We agree that the formation of Cristoballite can occur if AES down, etc.). In addition it is rather unlikely to fibres are used above 900 °C. But (according to a literature do completely without RCF material in high search) at present no published data regarding the exposure 1 Nyserda – New York State Energy Research and Development Authority: Hydrogen Production – Steam Methane Reforming (SMR), w.y., p. 1. http://www.getenergysmart.org/files/hydrogeneducation/6hydrogenproductionsteammethanereforming.pdf 2 Some references of using AES-products for several industrial applications could be found e.g. under http://www.thermalceramics.com/site.asp?siteid=146&pageid=163 3 TRGS 619 (English Version): Technical Rule for Hazardous Substances- Substitute materials for aluminium silicate wool products, http://www.baua.de/nn_16800/en/Topics-from-A-to-Z/Hazardous-Substances/TRGS/TRGS-619 - 2 - temperature units either: some joints have level of Cristoballite from AES fibres is available. to be sealed with flexible temperature It is also important to note that the formation of cristoballite from resistant material – RCF is in most cases RCF fibres can occur as well (Class, 20024). In addition Class5 the best compromise of durable function (2003) has shown that Cristoballite exposure in the course of and economic matters. removal operations can exceed the limit value used in a number Comments on the proposals: of countries (0.05 mg/m3). The average concentration as Classification of AES fibers exposed to high presented in the quoted literature is about 0.096 mg/m3. The 3 temperatures for long duration as products proposed OSHA limit value for crystalline SiO2 is 0.025 mg/m containing crystalline silica and also the (ICSC 08086). clarification of the methodology used to To our knowledge these statements do not correspond with the measure exposure levels to fibers may be latest results in research/ state of technology on the field of RCF correct approaches but doesn't change the substitution. Just recently7 a new microporous calcium fact that AES fiber material is not suitable hexaluminate insulating material has been developed called for SMR linings at all (due to its limited SLA-92.8 This material is fiber- and silica-free (low level of total application temperature). impurities – SiO2 and Fe2O3 contents each are maximum Selas-Linde shares the acknowledgement 0.1%)9. Aggregate enables the formulation of: castables, that no validated substitute for RCF exists gunning mixes (e. g. could be used to fill joints), bricks. SLA-92 4 P. Class, R.C. Brown;Exposition gegenüber künstlichen Mineralfasern, Gefahrstoffe – Reinhaltung der Luft; 62, Nr. 5, 2002 5 P. Class; Current Fibrous Dust Workplace Concentrations and Trend in the High Temperature Insulation Wool Industry: the Results of the Care programme, VDI-Bericht Nr. 1776, 2003 6 ICSC: International Chemical Safety Card No. 0808, Crystalline silica, quartz Crystalline silicon dioxide, quartz Silicic anhydride SiO2 , Molecular mass: 60.1 7 Bundesministerium für Wirtschaft und Arbeit BMWA, Project No. 032 7258 8 Super Lightweight Aggregate of 92% Al2O3. 9 Wuthnow H.; Pötschke J.; Buhr A.; Boßelmann D.; Pozun F.; Gerharz N.; Golder P.; Grass J.; (w.y.), p. 200. 10 The lower thermal conductivity, the better insulation. 11 Overhoff, A.; Buhr, A.; Grass, J.; Wuthnow, H. (2005), p. E3. 12 Kockegey-Lorenz, R.; Buhr, A.; Racher, R. (2005), p. 19. 13 Boßelmann, D.; Buhr, A.; Gerharz, N.;Golder, P.; Grass, H.-J.; Overhoff, A.; Wuthnow, H.; Pötschke, J (2004), p. 5. 14 Kockegey-Lorenz, R.; Buhr, A.; Racher, R.: Industrial Application Experiences with Microporous Calcium Hexaluminate Insulating Material (presentation), 48th-International Colloquium on Refractories, Aachen, September 2005 – SLA-92, p. 19 15 http://www.ultraliteinsulation.com/pdf/Ideal_Standard_Case_Study_v2-2.pdf 16 http://www.ultraliteinsulation.com/pdf/UltraliteB_%20HT_Data_Sheet.pdf 17 http://www.ultraliteinsulation.com/kilncarbase.html 18 Open porosity by 88%. 19 http://www.promat.de/twd/default.asp?PAGE=NEWS&LANGUAGE=E 20 http://www.cellaris.com/pictures/files/Cellaris%20Company%20Profile%2001102009.pdf and www.cellaris.com http://www.cellaris.com/pictures/files/Insulation.pdf 21 http://www.cellaris.com/contents/page.asp?contentPageID=31&contentCatID=26 22 http://www.microthermgroup.com/EXEN/site/markets-detail.aspx?vPK=51&k=15&l=6&page=0 23 http://www.microthermgroup.com/EXEN/site/products-detail.aspx?vPK=31&k=3&l=1 24 Microtherm – Product Performance Brochure, p. 7. http://www.microthermgroup.com/EXEN/site/downloads-overview.aspx?k=194&l=8 - 3 - for SMR application under consideration of has similar technical properties like RCF: low density, low economic aspects. thermal conductivity 10 of 0.36 W/m*K at 1200°C (vs. RCF of 0.41-0.44 W/m*K at 1200°C)11, long term stability is up to 1500°C, excellent resistance to thermal shock, chemical stability e.g. calcium hexaluminate has excellent resistance to alkali or carbon monoxide (CO) attack and hydrogen (H2) containing reducing process atmosphere and low shrinkage.12 In addition calcium hexaluminate has thermal expansion and fracture 13 toughness comparable to α-Al2O3 (corundum) . All these listed technical properties are required for the SMR process (see above) and allow likewise RCF to save energy consumption therefore CO2-emission could be reduced. In general the new developed material SLA-92 has better thermal insulating properties due to lower thermal conductivity as RCF particularly in high temperature range.
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