Electronic Grade High Purity Silica Sand Production Line Project & System
System Overview
This system is a complete solution designed for the production of electronic-grade high-purity silica sand, specializing in the production of electronic-grade high-purity silica sand with purity up to 5N-6N (99.999%-99.9999%) and the content of key metal impurities less than 1 ppm through advanced processes such as precision crushing, thermal activation, in-depth chemical purification, high-temperature chlorination treatment and ultra-fine grading. The products are mainly used in semiconductor quartz crucibles, wafer carriers, photomask substrates and other high-end electronic manufacturing fields.
Detailed process flow of the whole line
Raw Material Precision Pretreatment System
Selected high-grade quartzite ore is double-selected by color sorter and X-ray sorter to effectively eliminate impurity-containing grains; ceramic liner jaw crusher and cone crusher are used for multi-stage crushing to process the raw material to a particle size of less than 5mm, avoiding metal contamination throughout the whole process, and laying a foundation for the subsequent in-depth purification.
Thermal activation and lattice optimization system
The crushed material is heat-treated in a 1250°C high-temperature electric kiln, inducing micro-crack networks within the mineral through a precisely controlled quenching process; this process effectively opens up the lattice channels, which significantly improves the reaction efficiency of the subsequent chemical reagents with the impurity components, and exposes the inclusions to the full extent of the impurities.
Multi-mode Deep Impurity Removal System
-
High-voltage electrowinning separation: equipped with 40kV high-voltage electrowinning machine, based on the difference in electrical conductivity of minerals to achieve accurate separation.
-
Superconducting magnetic separation and purification: 6T superconducting magnetic separation system is adopted to remove paramagnetic impurities such as iron, cobalt and nickel in depth.
-
Flotation refining: using customized surfactants in acidic media to efficiently separate feldspar, mica and other aluminosilicate minerals.
Chemical Deep Purification System
The materials are deeply leached in a Teflon lined reactor for 72 hours at 90°C with high purity mixed acid to completely dissolve the metal impurities in the surface inclusions and lattice channels; 18 megohm ultrapure water is used for fifteen stages of countercurrent rinsing to ensure that the residual amount of acid radical ions is less than 0.05ppm.
High temperature chlorination purification process
Passing electronic grade chlorine under 1300°C high-purity nitrogen environment, so that stubborn impurities such as alkali metals, transition metals and so on generate gaseous chloride to volatilize and remove, the removal rate of uranium, thorium and other radioactive elements can reach more than 99.95%, and the content of key metal impurities is stably controlled at 0.1-0.5ppm.
Ultra-fine grading and finished product processing
The multi-stage turbine air classifier realizes precise control of 1-20μm particle size, and is equipped with on-line laser particle sizer to monitor the particle size distribution in real time; the finished products are packaged in nitrogen-filled packaging in a class 100 clean environment to ensure that the product maintains ultra-high purity during storage and transportation.
System Core Advantages
Ultimate purity guarantee system
Integrating the three core technologies of thermal activation, deep chemical purification and high-temperature chlorination to build a complete purification chain, ensuring that the purity of the product reaches the 5N-6N standard stably, and the content of key metal impurities is controlled within the range of 0.1-1ppm.
Precise particle size control technology
Adopting multi-stage grading process combining airflow grading and centrifugal grading, the product particle size distribution concentration D90/D10≤1.5, to meet the ultimate requirements for powder consistency in the field of electronic materials.
Clean production in the whole process
The core process is completed in a class 100 clean environment, and the equipment is made of high-purity quartz, PTFE and other inert materials to fully eliminate the risk of secondary pollution in the production process.
Intelligent quality traceability
Introducing MES production execution system to implement full traceability of raw material batches, process parameters, quality data, and establish a perfect quality file to ensure that each batch of products can be traced back to the original production data.
Project Configuration
Clean production area planning
Raw material pre-treatment area adopts class 10,000 clean standard, chemical purification and finished product processing area carries out class 100 clean specification, and each area realizes cleanness grading control through air shower room and material transfer window.
Specialized equipment configuration plan
-
Crushing section: equipped with zirconia ceramic liner crushing equipment, completely avoiding metal pollution.
-
High-temperature treatment: adopting silicon carbon rod kiln, with temperature control accuracy of ±1°C.
-
Classification system: equipped with high-precision turbine classifier, classification efficiency ≥ 90%.
-
Testing center: equipped with high-precision analytical instruments such as ICP-MS, GD-MS, etc.
Environmental protection and safety system
Acidic waste gas is discharged after three-stage absorption treatment to meet the standard, and chlorination tail gas is harmlessly treated through a special treatment system; a chemical emergency treatment device is set up to comprehensively guarantee production safety.
Through the perfect combination of extreme purification process and clean production system, this program provides the electronics industry with high-purity silica sand products of stable quality and excellent performance, and helps the development of semiconductors, integrated circuits and other strategic emerging industries.
