Invention Grant
- Patent Title: Method for producing synthetic quartz glass granules
- Patent Title (中): 生产合成石英玻璃颗粒的方法
-
Application No.: US14390991Application Date: 2013-03-20
-
Publication No.: US09409810B2Publication Date: 2016-08-09
- Inventor: Walter Lehmann , Thomas Kayser
- Applicant: Heraeus Quarzglas GmbH & Co KG
- Applicant Address: DE Hanau
- Assignee: Heraeus Quarzglas GmbH & Co. KG
- Current Assignee: Heraeus Quarzglas GmbH & Co. KG
- Current Assignee Address: DE Hanau
- Agency: Tiajoloff & Kelly LLP
- Priority: DE102012006914 20120405
- International Application: PCT/EP2013/055772 WO 20130320
- International Announcement: WO2013/149831 WO 20131010
- Main IPC: C03B20/00
- IPC: C03B20/00 ; C03B19/09 ; C03B19/10 ; C03C23/00

Abstract:
The production of quartz glass granules comprises the granulation of pyrogenically produced silicic acid and the formation of a SiO2 granulate (9), the drying and cleaning of the SiO2 granulate (9) by heating in an atmosphere containing halogen, and the vitrification of the SiO2 granulate (9) under a treatment gas which contains at least 30% by volume of helium and/or hydrogen. This process is time-consuming and expensive. In order to provide a method which, starting from a porous SiO2 granulate (9), allows the cost-effective production of dense, synthetic quartz glass granules suitable for melting bubble-free components of quartz glass, the invention proposes that the cleaning and vitrification of the SiO2 granulate (9) and a post-treatment of the vitrified quartz glass granules are carried out in each case in a rotary tube (6) of a rotary kiln (1), said rotary tube rotating about a central axis (7), wherein the rotary tube (6) comprises an inner wall made of a ceramic material during vitrification, and wherein the vitrified quartz glass granules are subjected to a post-treatment during a treatment period of at least 10 minutes in an atmosphere which contains less than 20% of helium or hydrogen at a treatment temperature of 300° C. or more.
Public/Granted literature
- US20150059407A1 METHOD FOR PRODUCING SYNTHETIC QUARTZ GLASS GRANULES Public/Granted day:2015-03-05
Information query