Double-effect MVR evaporators are suitable for evaporation, concentration, and crystallization in industries such as chemical, food, pharmaceutical, printing and dyeing, environmental engineering, and waste liquid evaporation and recovery, especially for materials with crystallinity, high concentration, and high viscosity. Examples include the recovery of sodium chloride, sodium sulfate, ammonium chloride, and ammonium sulfate.

MVR Evaporator Introduction:

The MVR (Mechanical Vapor Recompression) system uses a compressor to perform work on the secondary steam generated in the evaporation system, increasing the steam's enthalpy and circulating it for heating and evaporation. This fully utilizes the waste heat from the secondary steam and condensate within the system, resulting in significant energy savings. It eliminates the need for fresh steam, saving over 90% of condensate, 80% of manpower, and 60% of space.

MVR evaporators use secondary steam compressed by a compressor. Domestic compressors can provide a temperature rise of 20°C per unit, while imported compressors can provide a temperature rise of 9°C per unit. Therefore, the evaporator system requires the inlet water to have a boiling point as low as possible below 15°C to achieve energy-efficient evaporation.

Double-effect: The live steam is used twice in the system.

The difference between MVR and multi-effect evaporators is that secondary steam is constantly recycled within the system, so its energy is not wasted.

The system consumes energy to raise the temperature from 119°C to 130°C, which is the energy consumed by the compressor. The energy saving of MVR is reflected in the fact that it only requires an input of 16KJ (tons of water) to turn secondary steam from useless to useful.

Advantages of MVR evaporators:

High heat transfer coefficient: This type of evaporator has a variable flow field, which makes it easy for the liquid to reach a vigorous turbulent state. Its heat transfer coefficient is 2-3 times that of the shell and tube type.

Not prone to clogging: The liquid forms a turbulent flow on the heat exchange surface, which can flush the heat exchange surface, causing the scale adhering to the heat exchange surface to fall off and delaying the scaling cycle.

Smooth surface: Utilizing mature processing technology, the surface roughness of the heat exchange surface is controlled at a low value, making it difficult for contaminants to adhere. The scaling rate of this type of heat exchanger is only 1/5 that of a shell-and-tube heat exchanger;

Easy to clean and maintain: The plate structure allows for easy disassembly of the heat exchange surface, and any contaminated or damaged heat exchange surface can be easily replaced.

Suitable for: evaporation and crystallization of various inorganic salts, evaporation of liquids with high hardness, evaporation and concentration of landfill leachate, concentration of liquids in the food, fermentation, and pharmaceutical industries, and concentration of heat-sensitive materials.

MVR evaporator product composition:

Preheater: In most cases, the solution to be evaporated needs to be preheated before entering the evaporator.

Evaporator: The solution to be evaporated is heated by a heat source, steam, in the evaporator to produce evaporation. Different types of evaporators are selected according to the properties of different solutions.

Separator: Used for separating vapor and liquid. Different separators can be selected according to the properties of different solutions. Generally, there are centrifugal separators, gravity separators or separators with special structures.

Various types of pumps: Used to transport solutions to be evaporated and concentrated solutions. Different types of pumps are selected according to the different properties of the solution; generally, centrifugal pumps, positive displacement pumps, and screw pumps can be used.

Compressor: Provides a heat source for evaporation by compressing secondary steam, thereby increasing the enthalpy of the secondary steam. Various compressors can be selected based on different flow rate and compression ratio requirements. For situations requiring increased pressure rise, multi-stage compressors can be used in series.

Control System: The MVR evaporation system control center regulates motor speed and controls valves, flow meters, temperature, and pressure to achieve automatic evaporation, cleaning, and shutdown operations. It features automatic alarms, automatic system protection against damage, and maintains system dynamic balance.

Cleaning system: Different solutions may cause scaling after evaporation for a period of time. Generally speaking, more than 99% of scaling is removed by adding chemical solvents. CIP in-situ cleaning or disassembly cleaning can usually be used.