Natural Circulation / Rising Film Evaporators

Name: Natural Circulation Rising Film Evaporators
Brand: Buflovak
Availability: InStock

Natural circulation in an evaporator is caused by the thermal difference between the heating medium and the liquid. This thermal change is called “thermo-siphon action”. Sufficient heat must be available to provide the necessary thermal difference to cause circulation.

Product Details

Operating a Natural Circulation / Rising Film Evaporators is extremely simple. The body and tubes are partially filled with liquid and steam is admitted to the steam chest. Dilute liquid at the proper temperature is fed to the chamber below the lower tube sheet. When the boiling point is reached, bubbles of vapor are formed in the column of liquid. As they expand and increase in volume they push the liquid ahead with increasing velocity. As the upper part of the tubes is reached, the liquid is either in the form of drops or a film in contact with the wall of the tubes.

The mixture of vapor and liquid merges from the tubes and enters the upper chamber from which it passes through a short connection into the vapor separator. Concentrated liquid is removed from the bottom of the vapor separator as a finished product or to serve as feed for another effect. Continuous operation is the ideal method of operating an evaporator, but there are processes where batch operation is necessary. Buflovak Natural Circulation / Rising Film Evaporators are adaptable to either application. The separator can be designed for any required holding capacity.

FEATURES & BENEFITS

Natural Circulation – Rising Film Evaporator

Rising vapor and liquid mixture create high velocities within the tubes.

Low residence time prevents degradation of heat-sensitive liquid materials.

Versatile and customizable design can be equipped with vapor separators to manage foaming products.

Rising film evaporators can be operated in a continuous mode, which is more energy and time-efficient than batch processing.

Simpler design and fewer pumps contribute to lower initial capital and operational expenses.

Natural circulation design minimizes the re-entrainment of liquid with the vapor stream.

Separates vapor from the liquid mixture at the top of the heating tubes producing high-quality distillate, making them suitable for water recovery or purification processes.

Provide Your Design Requirements

Design Requirements

Downloads

Buflovak-Evaporation-Distillation-Separation Group Brochure
Capabilities Brochure

Our experienced application engineers are ready to address your evaporative and crystallization needs.

Natural Circulation / Rising Film Evaporators – FAQs

How does a natural circulation rising film evaporator work?

These evaporators rely on a thermosiphon effect where heat causes vapor bubbles to form and push liquid upward through vertical tubes, creating natural circulation and forming a thin rising film along the tube walls.

What types of liquids are best suited for rising film evaporation?

Rising film evaporators are commonly used for dilute solutions, low- to medium-viscosity liquids, and heat-sensitive materials that require short residence times.

Why are rising film evaporators energy efficient?

The natural circulation design eliminates the need for recirculation pumps, reducing energy consumption and simplifying system design.

Can rising film evaporators operate continuously?

Yes. Many systems are designed for continuous processing, which improves production efficiency and throughput compared to batch operations.

What industries commonly use rising film evaporators?

Typical applications include food products, fruit juices, pharmaceuticals, nutraceuticals, chemical processing, and water purification.

Testing & Lab Rentals

Test your materials in one of our world-class pilot scale testing facilities. The Buflovak Research & Test Center located in Tonawanda, NY provides access to multiple dryers, flakers, single and double drum units, and cast iron and chrome plated drums. CPEG’s Innovation Center & Testing Lab in Louisville, KY, provides access to a variety of additional process equipment technologies for multistep processing. Lab rentals are available when it is not feasible to perform testing at one of our facilities.

Learn More