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Pursuing Ultrafine & High-Purity Materials | Integrated Nano Grinding & Spray Drying Production Line for Spherical Alumina Diaphragm Thermal Conductive Materials Empowers Lithium Battery Safety

Market Demand Analysis: Soaring Demand for Spherical Alumina

Manufacturing Process of High-Purity Alumina Ceramics: Transformation Path from Raw Ore to Precision Finished Products

1. Raw Powder Preparation: Achieve Ultrafine Granularity & Ultrahigh Purity

2. Green Body Forming: Customized Processes for Diverse Product Specifications

• Uniaxial pressing: Cost-effective for simple flat and cylindrical components;
• Isostatic pressing: Transmits uniform omnidirectional pressure via elastic molds to fabricate high-density, homogeneous green bodies for high-performance applications;
• Slip casting: Ideal for large thin-walled complex parts;
• Extrusion: Continuous manufacturing of tubular and rod-shaped products;
• Injection molding: Suits intricate 3D components such as internally threaded parts and micro turbine rotors, delivering high efficiency and consistent dimensional accuracy, with post-sintering debinding required to remove residual binders.

3. High-Temperature Sintering: The Critical Stage for Ceramic Densification

4. Precision Machining: Diamond Tool Finishing

Dual-Core Equipment: High-Flow Pin-Type Nano Bead Mill & High-Temperature Spray Drying Tower Empower Ultrafine, High-Purity Spherical Alumina

Advantages of the High-Flow Pin-Type Nano Bead Mill

1. A composite turbine-pin rotor structure drives materials along a 3D motion path combining circumferential vortex flow and radial impact. Paired with 0.3–0.5 mm zirconia grinding beads, triple forces of shear, collision and extrusion gradually refine particles. Spherical alumina D50 can be stably controlled between 100 nm and 2 μm, with narrower particle size distribution than the industry average, perfectly matching ultrafine powder requirements for separator coating.
2. A screenless centrifugal separation design eliminates metal screen contact with materials, restricting metallic impurities to an extremely low level and guaranteeing high alumina purity. It also prevents screen clogging caused by high-viscosity slurry or fibrous contaminants, extending continuous operation lifespan several times over conventional equipment and drastically lifting production efficiency.

Advantages of the High-Temperature Spray Drying Tower

1. Optimized hot air distribution and ultra-high-speed atomization atomize slurry into uniform micro-droplets that instantly dry upon contact with hot air, generating hollow spherical powder. The process retains ultrafine particle sizes achieved in grinding and resolves common issues of ultrafine powder agglomeration and poor flowability, supporting automatic feeding and uniform coating in subsequent separator manufacturing.
2. A new offline pulse bag dust collector with high-temperature-resistant filter bags and cold air protection system recovers over 99% of ultrafine spherical alumina powder without introducing secondary contamination during drying, further strengthening the product’s purity edge.

Longxin High-Flow Pin-Type Nano Bead Mill: Technical Details Deliver Superior Grinding Performance

1. A modular grinding assembly paired with an advanced screen-free separation system breaks the conventional integrated grinding-separation design constraints.
2. Turbine pin components are manufactured from tungsten carbide (HRC 90 hardness) with specialized surface coatings. Uniform energy density distribution is maintained at rotational speeds of 1200–1800 r/min to avoid localized over-grinding and particle agglomeration, ensuring consistent spherical alumina particle sizes.
3. The grinding chamber is constructed from silicon carbide (HV 1800+ hardness) with exceptional wear resistance and thermal conductivity. Its service life exceeds stainless steel by 5 times, while thermal conductivity triples that of stainless steel. Combined with jacket cooling, stable operating temperatures are maintained to prevent crystal phase transformation or oxidation of spherical alumina during grinding, securing consistent product performance.
4. The intelligent control system acts as the equipment’s operational brain. Equipped with PLC modules and real-time temperature, pressure and flow sensors, it continuously collects key process parameters and automatically adjusts rotor speed and feed flow via built-in algorithms. If particle size deviates from set targets, rotational speed is optimized autonomously to stabilize particle dimensions. The mill supports MES system connection, forming a full closed-loop workflow of online monitoring, real-time adjustment and data traceability to meet flexible multi-variety, small-batch production demands. Pre-stored process recipes for different alumina batches drastically shorten product changeover time.
5. Outstanding economic performance in energy consumption and maintenance: The silicon carbide grinding chamber’s superior heat transfer eliminates extra heat exchangers, cutting unit energy consumption by over 20% vs. traditional mills. High-efficiency small-diameter zirconia beads reduce grinding media consumption by 15% at equivalent throughput. Long-lasting wear-resistant components lower annual maintenance costs by 30%, delivering substantial economic benefits to manufacturers.

High-Temperature Spray Drying Tower: Refined Design Ensures Superior Dried Powder Quality

1. CFD fluid dynamics simulation optimizes the hot air distribution system. Simulated internal hot air flow patterns refine air duct geometry and inlet angles to form a uniform, stable swirling airflow field inside the tower. Full contact between atomized droplets and hot air avoids localized overheating that causes particle sintering or degradation, while delivering consistent moisture content across all powder to satisfy strict drying standards for separator coating materials.
2. Fully self-developed ultra-high-speed centrifugal atomizers deliver reliable performance with rotational speeds ranging from 15,000 to 25,000 r/min. Slurry is atomized into 5–50 μm uniform droplets to ensure consistent powder particle size after drying and eliminate coarse particle impurities. Precision dynamic balancing minimizes operational vibration and failure rates, outperforming competing industrial equipment in continuous run stability.
3. Interchangeable atomizer disks support diverse process requirements: Flat disks suit low-viscosity slurry to produce fine powder; turbine disks boost atomization efficiency for medium-to-high viscosity feedstock. Multiple disk options expand process adaptability for various grades and batches of spherical alumina.
4. Combined oil-air dual cooling systems stabilize high-temperature operation: The oil cooling loop rapidly dissipates heat from the atomizer spindle, while auxiliary air cooling maintains atomizer operating temperature below 80°C. The control system monitors atomizer speed, temperature, vibration as well as tower internal temperature and pressure in real time, triggering automatic alarms and parameter adjustments upon abnormalities to prevent equipment thermal damage and sustain uninterrupted production.
5. Advanced offline pulse bag dust collectors improve recovery efficiency and powder purity: CFD-optimized flow field structures eliminate airflow dead zones, paired with PTFE filter bags resistant to temperatures up to 300°C to capture over 99% of ultrafine alumina powder. Cold air shielding protects filter bags from direct contact with high-temperature hot air to extend service life. Offline ash cleaning enables filter maintenance without production shutdowns, sustaining continuous manufacturing and eliminating cross-contamination during cleaning to preserve alumina purity.

Integrated Multi-Dimensional Energy-Saving Technologies: Longxin Intelligent Develops High-Efficiency, Low-Consumption Spray Drying Systems

1. Hot Air Energy Management to Boost Thermal Efficiency

   • Optimized inlet-outlet temperature differential: Maximize inlet air temperature within powder moisture specifications to reduce required hot air volume.
   • Waste heat recovery system: High-temperature exhaust retains 10–20% of process heat, recovered via standard air-air heat exchangers or exhaust recirculation preheating modules. Recovered heat preheats fresh intake air to reduce main heater load and preheats feed slurry to 40–60°C to lower viscosity and improve atomization results.

2. Precision Process Parameter Control Reduces Energy Use at the Source

   • Elevated feed solid content: Raising slurry solid loading from 30% to 45–50% cuts evaporation volume by nearly 30%, directly lowering energy consumption by more than 20%. High-solid, low-viscosity slurry output from Longxin nano bead mills enables high-concentration feeding.
   • Intelligent atomization matching: Variable-frequency centrifugal atomizers dynamically adjust rotational speed based on slurry properties for uniform droplet sizes, preventing secondary drying from oversized droplets or fine powder loss. Consistent atomization shortens drying duration and eliminates wasted thermal energy.

3. Stable Continuous Feeding

• 3D thermal field monitoring: Multi-point temperature sensors installed at air inlet, drying zone and outlet generate real-time thermal distribution models.
• Adaptive algorithm parameter tuning: Automatically adjusts inlet air temperature, atomizer speed and exhaust air volume based on feed concentration and ambient temperature/humidity to maintain operation at the minimum effective energy point.
• Recipe storage & one-click switching: Pre-sets optimal drying curves for spherical alumina, boehmite, activated alumina and other materials to eliminate energy waste from trial-and-error process adjustments.

Intelligent Production Lines Drive Industrial Upgrading: Ultrafine High-Purity Spherical Alumina Safeguards Lithium Battery Performance

1. Product Performance Advantages

Technological Innovation Establishes New Standards for Alumina Ceramic Powder Manufacturing

Pursuing Ultrafine & High-Purity Materials: Integrated Nano Milling & Spray Drying Line for Spherical Alumina Diaphragm Thermal Conductive Materials Boosts Lithium Battery Safety