What is the Evaporator?

An evaporator is a device used for the process of turning the form of a substance from liquid to gaseous form or vapor and the process is known as evaporation.

Evaporator Systems Types:

• Falling Film Evaporators- The falling film evaporator is used for the heat exchanger. It consists of a vertical shell and a tube heat exchanger. The concentrated liquid is fed at the top of the tube and then flows down to the surface tube as a thin film. As it gets heated further, the vapors get generated. It increases the heat transfer and the vapor and liquid get separated further.

• Rising Film, LTV (Long Tube Vertical) Evaporators- The rising film evaporator is very similar to the falling film evaporator. It’s just the opposite of the falling film. It also consists of a vertical shell and a tube heat exchanger and it is also used for heat exchange. The concentrated liquid is fed at the bottom of the tube. As the heat increases further the vapors get generated and lift the liquid upward. As a result, the vapor and liquid get separated further.

• Forced Circulation Evaporators- Forced circulation evaporators are used to separate a mixture which is not possible by the normal evaporating unit. In the normal circular evaporator, the velocity of liquid flow is 0.3 to 1m/s but the forced circular evaporator increases the velocity of liquid flow to 2 to 6m/s. It contains a circulation pump and because of this, it is used for both heat exchanger and flash separation. It separates the mixture without using normal conventional boiling. It consists of a vertical shell and a heat exchanger tube with a centrifugal pump.

• Plate Evaporators- Plane evaporators consist of a plate and frame heat exchanger and are mainly used in the food and beverage industry. A plate evaporator is a type of evaporator in which a thin film of liquid is passed and flows between the plates for the process of evaporation. It is typically used for fruit juices, fruit puree, syrup, coffee, and milk.

• Thermal Vapor Recompression(TVR)- Thermal vapor recompression evaporator is a type of evaporator which is used as a thermal compressor to reduce the steam required for the process of evaporation. The vapor stream is compressed to a higher temperature and pressure by a steam jet pump.

• Mechanical Vapor Recompression (MVR)- Mechanical vapor recompression is a type of evaporator in which the water vapor is compressed which results in a rise in temperature and pressure. The rise in temperature makes the temperature difference between the vapor and the fluid. The further heat transfer results in a heat exchanger. The compressed vapor is again fed back to generate more steam. This is an energy efficient and energy recovery process.