Single Effect External Circulation Evaporator

Single Effect External Circulation Evaporator — Overview

I. Working Principle

Feed material is delivered by the feed pump into the tube-side of the heater. Heating steam transfers heat uniformly across the shell side. As the material is heated, its temperature rises and density decreases, causing it to naturally rise through the heater tubes into the evaporation-separation chamber. Under negative pressure, the material undergoes rapid flash evaporation and vapor-liquid separation. The secondary steam enters the condensation system for cooling and recovery. The cooled material, now denser, naturally flows back to the heating chamber via the external circulation pipeline through gravity and density difference, forming a stable continuous natural circulation loop. The material undergoes repeated heat exchange and concentration until the target concentration is reached, after which it is automatically discharged. The entire process operates without forced turbulent impact, ensuring gentle and stable concentration — ideal for heat-sensitive pharmaceutical liquid production.

II. Structure & Components

The equipment adopts a split-type modular structure with rational layout, convenient disassembly and maintenance, and zero sanitary dead zones. All core components are pharmaceutical-grade:

  1. Shell-and-Tube Heating Chamber: High-efficiency tube bundle structure with large heat exchange area, uniform heating and high thermal efficiency. Temperature, pressure and corrosion resistant for long-term continuous production.

  2. Vapor-Liquid Separation Chamber: Large-volume separation cavity with high-efficiency demister and mist eliminator to effectively intercept entrained droplets, preventing material loss and ensuring secondary steam cleanliness.

  3. Natural External Circulation System: Fully automatic natural circulation driven by temperature and density differences — no circulation pump required. Low energy consumption, low failure rate, low operating noise, suitable for long-term stable continuous production.

  4. Condensation Recovery System: Shell-and-tube condenser with liquid storage tank. Excellent condensation performance and high solvent recovery rate. Supports solvent recycling for energy conservation and environmental protection.

  5. Vacuum Negative Pressure System: Paired vacuum pump unit for stable negative pressure maintenance, enabling low-temperature evaporation to protect heat-sensitive material activity.

  6. Intelligent PLC Control System: Fully automatic PLC control with real-time monitoring of temperature, vacuum level, liquid level and concentration. Automatic feeding, concentration, discharge and shutdown with full parameter traceability.

  7. CIP Online Cleaning System: Pre-configured automatic cleaning interface for complete in-place cleaning without disassembly, meeting GMP clean production requirements.

Natural Circulation Evaporator — Technical Specifications (WZ Series)