Vertical Ribbon Mixer, Doebritz Industrial Blender, 3000L Capacity / ATEX Certified for Bulk Solids

Product Summary

The Doebritz Vertical Ribbon Mixer is a heavy-duty industrial blending solution engineered for high-volume homogeneous mixing of dry powders, granules, and flaky materials. With capacities ranging from 500L to 30,000L, an ATEX certified explosion-proof configuration (Cat. 2/22), and a proprietary dual-helix ribbon rotor design, this unit guarantees a CV < 5% after just 3–5 minutes of mixing. The bottom discharge valve and seal system achieve an air leakage rate ≤ 0.005 m³/min, ensuring dust-tight operation for pneumatic conveying integration.

Why Source Doebritz Vertical Ribbon Mixer

As a global OEM supplier with 15+ years serving Fortune 500 cement, chemical, and food processors, Doebritz delivers procurement advantages that directly impact your total cost of ownership (TCO).

• Ultra-Low Air Leakage (<0.005 m³/min): Prevents product loss and dust emissions, exceeding ISO 14000 standards. Our in-house CNC-machined rotor-to-housing clearance is held to ±0.1mm.
• ATEX Zone 2/22 Certified: Full documentation for explosive dust environments (St1, St2). Includes anti-sparking rotor and grounded shaft.
• 3X Longer Bearing Life: Outboard mounted, grease-lubricated bearings with purged air seals keep contaminants out – proven in 24/7 fly ash and carbon black lines.
• 30% Faster Changeover: Quick-release clamps and CIP spray nozzles available for sanitary applications (304/316L stainless steel).
• Global Logistics & Lead Times: 20 working days for standard cast iron units; rush assembly available for critical OEM shutdowns.

Housing & Rotor Engineering

The Doebritz Vertical Ribbon Mixer features a one-piece cast manganese steel or 316L stainless steel housing with 10mm wall thickness (wear plates optional). The U-shaped trough and conical bottom eliminate dead zones. The rotor comprises inner and outer helical ribbons made from abrasion-resistant AR400 steel – the outer ribbon moves material forward and up, while the inner ribbon moves backward and down, creating a true three-dimensional convection mix. All welds are 100% dye-penetrant inspected. The shaft is heat-treated 4140 alloy steel with a square key drive to prevent slippage under high torque (up to 15,000 Nm).

Technical Specifications

All Doebritz mixers are tested and certified per GMP, FDA (for food-grade finishes), and ATEX 2014/34/EU. Below are typical values; customized capacities, discharge valve types (slide gate, rotary airlock, or ball valve), and inlet flanges (ANSI, DIN, JIS) are available.

Specification	Detail
Total Capacity	500 – 30,000 Liters (working ratio 60-80%)
Body Material	Cast Manganese Steel / SS304 / SS316L
Rotor Design	Dual helical ribbons, AR400 wear plates
Drive Power	5.5 kW – 160 kW, IE3 motor (IE4 optional)
Speed (RPM)	20 – 65 RPM (variable frequency drive ready)
Seal Type	Viton or PTFE packing / air-purged gland
Max Temperature	-20°C to +200°C (graphite option to 450°C)
Surface Finish	As-cast, shot blast, or sanitary mirror (Ra ≤ 0.8µm)
Discharge Valve	Slide gate / Diverter / Doebritz rotary airlock

Heavy-Duty Application Scenarios

Pneumatic Conveying Systems

Directly mount the Doebritz Vertical Ribbon Mixer above a dilute or dense phase pneumatic conveyor. The live bottom discharge flange (matched to our Doebritz rotary airlock) maintains system pressure while feeding the blender. This eliminates intermediate hoppers and reduces ceiling height requirements.

Silo Discharging & Blending

When installed under multiple silos, the mixer homogenizes off-spec material or creates customized blends (e.g., cement + slag + fly ash). The vertical design allows gravity feed from silos above and direct discharge to packing lines or tankers.

Dust Filter Collectors

For batch mixing of dusty powders (carbon black, lime, organic pigments), the integrated vent connection (DN150) connects to a dust collector, ensuring negative pressure during loading. Optional explosion venting panels meet NFPA 69 standards.

Frequently Asked Questions

Q1: What is the minimum order quantity (MOQ) for a Doebritz Vertical Ribbon Mixer?

A: One unit. We supply both single prototypes for pilot plants and full production lines. Lead time for 1–2 units is 4 weeks; bulk OEM orders (10+ units) get priority scheduling.

Q2: Can you customize the discharge flange and inlet connection?

A: Yes. Standard connections are ANSI #150 or DIN PN10. We can machine any bolt pattern – square, rectangular, or circular – and provide adapter plates for existing silo outlet flanges. No engineering fee for non-standard flanges on orders over 2 units.

Q3: Is the ATEX certificate valid globally?

A: Our certificate (TÜV Nord) covers EU ATEX directive and is widely accepted in USA (when paired with NEC 500 classification), Middle East, and SE Asia. We also provide IECEx certification upon request at no extra cost for Zone 21/22 applications.

Q4: What high-temperature options exist?

A: Standard Viton seals handle up to 200°C (continuous). For >200°C to 450°C, we offer graphite-packed stuffing boxes with cooling jackets on housing and shaft. Thermal expansion gaps are CNC pre-calculated.

Q5: Do you provide wear parts and on-site commissioning?

A: Yes. We stock ribbons, shaft seals, and bearings globally (Houston, Rotterdam, Shanghai). Our service engineers can commission the mixer with your pneumatic system or SCADA via remote VPN or on-site visit (72-hour response).