A pressure and vacuum rated bottom entry homogenizer combines a standard rotor-stator workhead with a pressure-rated mechanical seal and vessel connection, enabling homogenisation under positive pressure or vacuum. Used where solvent containment, inert atmosphere processing, or vacuum degassing during homogenisation is required alongside the bottom-entry benefit of eliminating particle settling.
Challenges
Mechanical Seal Must Withstand Pressure in Both Directions
The seal must maintain integrity under positive pressure and vacuum in the same installation, as vacuum pulls seal faces apart while positive pressure pushes them together, requiring a more complex and costly seal design than single-direction configurations.
Vessel Base Structural Integrity Under Cyclic Pressure Loading
The bottom entry penetration represents a stress concentration that must be engineered for the full number of pressure and vacuum cycles expected over the vessel service life, to prevent fatigue failure at the flange connection.
Safe Maintenance Access Under Residual Pressure
Accessing the bottom workhead requires confirmed full depressurisation before the flange can be opened safely, requiring reliable pressure instrumentation and physical interlocking to prevent unsafe access under residual pressure.
Solutions
- Bidirectional Pressure-Rated Double Mechanical Seal with Barrier Fluid: A double seal with barrier fluid pressure maintained between faces above both maximum process pressure and maximum vacuum ensures correct seal face loading direction regardless of vessel operating mode throughout the full pressure range.
- Fatigue-Rated Bottom Flange Engineering: Designing the bottom entry flange and vessel base connection to a fatigue-rated standard appropriate for the expected number of pressure and vacuum cycles over the full vessel service life prevents structural failure at the penetration point.
- Pressure Interlock on Bottom Flange Access: A physical interlock preventing bottom flange opening until vessel pressure is confirmed at atmospheric by independent instrumentation protects maintenance personnel from residual pressure hazards during workhead inspection and replacement.
Applications
- Pharmaceutical Solvent-Based Dispersion Under Full Containment: Homogenisation of formulations containing volatile organic solvents in sealed pressure-rated vessels, preventing solvent loss, maintaining formulation composition, and protecting personnel throughout the complete batch processing cycle.
- Vacuum Degassing Combined with Bottom Entry Homogenisation: Production of bubble-free pharmaceutical creams, gels, and sterile emulsions by applying vacuum during homogenisation, with bottom entry simultaneously ensuring complete batch turnover and elimination of settled particles.
- Oxygen-Sensitive Emulsification Under Inert Atmosphere: Batch emulsification of oxidation-sensitive oils, bioactives, and antioxidant ingredients under positive nitrogen pressure, preventing oxidative degradation while maintaining complete bottom circulation and particle suspension throughout the batch.
Product Catalogue & Technical Datasheet
Model | Scale | Power (HP / kW) | Speed (RPM) | Flow Rate (L/h) | Particle Size (µm) | Viscosity Max (cP) | Tip Speed (m/s) | Shear Rate (s⁻¹) | Op. Temp (°C) | Op. Pressure (bar) |
BEHH-LAB-01 | Lab | 0.5 / 0.37 | 1,500–3,000 | 10–50 | <1–20 | 20,000 | 5–15 | 10³–10⁴ | 0–150 | -1 to 6 |
BEHH-LAB-05 | Lab / Pilot | 1.0 / 0.75 | 1,500–3,000 | 50–200 | <1–20 | 50,000 | 8–20 | 10³–10⁵ | 0–150 | -1 to 6 |
BEHH-PIL-10 | Pilot | 5 / 3.7 | 1,500–3,000 | 200–1,000 | <1–15 | 80,000 | 10–22 | 10³–10⁵ | 0–150 | -1 to 6 |
BEHH-PIL-20 | Pilot | 10 / 7.5 | 1,500–3,000 | 500–2,000 | <1–10 | 100,000 | 12–25 | 10⁴–10⁵ | 0–150 | -1 to 6 |
BEHH-100 | Production | 20 / 15 | 1,500–3,000 | 1,000–5,000 | <1–10 | 100,000 | 12–25 | 10⁴–10⁵ | 0–150 | -1 to 6 |
BEHH-300 | Production | 40 / 30 | 1,500–3,000 | 2,000–10,000 | <1–5 | 100,000 | 15–25 | 10⁴–10⁵ | 0–150 | -1 to 6 |
BEHH-600 | Production | 60 / 45 | 1,500–3,000 | 5,000–20,000 | <1–5 | 100,000 | 15–25 | 10⁴–10⁵ | 0–150 | -1 to 6 |
BEHH-HP-100 | Large Prod. | 100 / 75 | 1,500–3,000 | 10,000–40,000 | <1–3 | 100,000 | 18–25 | 10⁴–10⁵ | 0–150 | -1 to 6 |