1. Einführung
Kieselerde, auch Mikrosilica genannt, is a byproduct of the production of silicon or ferrosilicon alloy. This amorphous form of silica is known for its high reactivity, making it an essential component in the production of high-performance concrete. This quality control manual outlines the steps to ensure the highest quality and consistency of Silica Fume produced.
2. Product Description and Specifications
Silica Fume is an ultrafine material with spherical particles less than 1 μm in diameter, the average being 0.15 μm. The standard specifications include:
SiO2-Gehalt: Greater than 85%
Feuchtigkeitsgehalt: Less than 3%
Zündverlust: Less than 6%
Spezifische Oberfläche: 15-30 m2/g
3. Fertigungsprozess
The Silica Fume is captured from the gas released in the production of silicon and ferrosilicon alloy. The gas undergoes cooling, condensation, and collection to produce silica fume.
4. Quality Control Procedures
The main steps in the quality control process include:
4.1 Regular Sampling
An der Produktionslinie sollten in regelmäßigen Abständen Proben von Silica-Rauch entnommen werden. Diese sollten für das Produkt repräsentativ sein und in verschiedenen Produktionsstadien erfasst werden.
4.2 Testen
An den Proben werden mehrere Tests durchgeführt, um ihre Eigenschaften zu bestimmen. Diese Tests umfassen:
- SiO2-Gehalt: Bestimmen Sie den SiO2-Gehalt durch chemische Analysemethoden wie Röntgenfluoreszenz (RFA) oder optische Emissionsspektroskopie mit induktiv gekoppeltem Plasma (ICP-OES).
- Feuchtigkeitsgehalt: Determine the moisture content by drying a known mass of Silica Fume at a constant weight in an oven set at 105°C.
- Zündverlust: Determine the loss on ignition by heating a known mass of Silica Fume in a furnace at 950°C for 1 hour and calculating the weight loss.
- Spezifische Oberfläche: Determine the specific surface area using the BET (Brunauer, Emmett and Teller) method.
4.3 Record Keeping
Detailed records of all tests performed and their results should be maintained. These records are necessary for tracking product quality over time and identifying potential issues.
5. Non-compliance Procedures
In case the product does not meet the required quality standards, several corrective actions may be taken. These could include reprocessing the silica fume, investigating the cause of non-compliance, or adjusting the production process to prevent future non-compliance.
6. Staff Training
Staff involved in the production and quality control of Silica Fume need to be adequately trained. They should understand the production process, the importance of maintaining product quality, and the procedures for testing and recording results.
7. Review and Updates
This manual should be reviewed regularly and updated as necessary to reflect changes in production processes, testing methods, or quality standards.
Please note that this is a general guide. Depending on your region, Möglicherweise müssen bei der Herstellung und Prüfung von Quarzstaub bestimmte Standards eingehalten werden. Konsultieren Sie immer einen örtlichen Branchenexperten oder eine Aufsichtsbehörde, um die Einhaltung sicherzustellen.
