Multiple Effect Evaporators - Introduction

Summary

This video explains the operation of a triple effect evaporator, where steam enters the first effect and condenses to heat the liquid. The evaporator works in stages: the vapor from the first effect heats the second, and the vapor from the second heats the third. Each effect operates under different vacuum levels, maintaining distinct boiling temperatures for the liquid. The process minimizes energy usage by reusing heat from previous effects. The final concentrated product exits from the third effect, and condensate is discharged at each stage, ensuring efficient evaporation across all three stages.

Takeaways

• 😀 Steam enters the first effect of the triple effect evaporator as the heating medium.
• 😀 Condensate leaves the first effect's heating section at the bottom.
• 😀 Raw juice enters from the bottom and rises in the tubes, where it heats up.
• 😀 Some of the liquid turns into vapor as it moves up, while the rest becomes concentrated liquid.
• 😀 Vapors from the first effect are passed into the second effect as the heating medium.
• 😀 In the second effect, the vapors condense, and the condensate exits at the bottom.
• 😀 The concentrated stream from the first effect moves to the second effect at the bottom of the heating section.
• 😀 Vapors from the second effect enter the third effect as the heating medium, continuing the cycle.
• 😀 In the third effect, vapors discharge their heat, and the condensate leaves at the bottom.
• 😀 The concentrated liquid from the second effect is fed into the third effect, where more vapors are released.
• 😀 The vapors from the third effect are discharged into the atmosphere, and the final concentrated product exits the system.
• 😀 The heating in the second and third effects is powered by vapors from the preceding effects rather than new steam.

Q & A

What is the primary function of a triple effect evaporator?

The primary function of a triple effect evaporator is to concentrate a liquid by utilizing steam and vapors in multiple stages to reduce energy consumption while removing water from the liquid.

How does steam enter the triple effect evaporator?

Steam enters the triple effect evaporator through the first effect, where it serves as the heating medium for the liquid.

What happens to the condensate in the first effect?

In the first effect, the condensate leaves at the bottom of the heating section after steam heats the liquid.

How does the raw juice enter the evaporator?

The raw juice enters the evaporator from the bottom of the first effect and rises through the heating section, where it gets heated.

What happens to the raw juice as it rises in the evaporator?

As the raw juice rises in the evaporator, some of it turns into vapor, while the remaining liquid becomes more concentrated and moves downward.

What happens to the vapors from the first effect?

The vapors from the first effect leave and enter the second effect, where they serve as the heating medium.

What heating medium is used in the second effect?

In the second effect, the heating medium is the vapor from the first effect, which condenses in the heating section.

How is the concentrated liquid handled in the second effect?

The concentrated liquid from the first effect is fed into the second effect at the bottom, where it rises and releases more vapors as it heats.

How does the evaporator handle the vapors in the third effect?

In the third effect, the vapors from the second effect are used as the heating medium. They release their heat, condense, and leave the system as condensate.

What happens to the concentrated liquid in the third effect?

The concentrated liquid from the second effect is fed into the third effect, where it rises, releases more vapors, and the vapors are discharged into the atmosphere.

Why is a vacuum maintained in each of the effects?

A vacuum is maintained in each effect to control the boiling temperature of the liquid, ensuring that it boils at different temperatures in each effect and that the process operates efficiently.

What is the role of different vacuum levels in the triple effect evaporator?

The different vacuum levels in each effect maintain distinct boiling temperatures, which helps in efficient evaporation and concentration of the liquid at each stage.