Thermal vapour recompression evaporation widely used for Evaporation Consentration and crystallization
Thermal Vapor Recompression (TVR)
A method to reduce the energy consumption of a steam heated evaporator system.
Uses high pressure steam as the motive fluid to a steam ejector,to entrain recycled lower pressure steam and discharge the combined steam at a more useful intermediate pressure.
The vapor compression cycle rlies on the condensation temperature of the lower pressure steam increasing with the increase in pressure.
Scope of application:
Thermal steam recompression evaporation crystallizer is widely used in food, starch, beverage, pharmaceutical, pesticide, chemical and other industries, as well as an evaporation and concentration equipment in the fields of high-concentration wastewater in environmental water treatment projects. It is especially suitable for the evaporation, concentration and crystallization of inorganic salts such as sodium chloride, caustic soda and concentrated solutions containing organic solvents.
System composition:
Preheater, steam compressor, evaporator, separator, circulating pump, electrical control system, pipeline connection system, steel frame platform and other systems.
When thermal steam is recompressed, according to the heat pump principle, the steam from the boiling chamber is compressed to a higher pressure in the heating chamber; that is, energy is added to the steam. Since the saturated steam temperature corresponding to the pressure in the heating chamber is higher, the steam can be reused for heating. For this purpose, a steam jet compressor is used. They operate according to the principle of jet pumps, have no moving parts, are simple and effective in design, and ensure the highest working reliability.
Using a thermal vapor compressor has the same steam/energy saving effect as adding an effect evaporator. The operation of the thermal vapor compressor requires a certain amount of live steam, the so-called motive steam. These motive steam must be sent to the next effect, or sent to the condenser as residual steam. The remaining energy contained in the residual steam is approximately equivalent to the energy provided by the motive steam.
Part of the secondary steam from the separator is driven by the high-pressure working steam and enters the ejector to mix, raise the pressure, and then enter the heating chamber as heating steam to heat the liquid. The other part enters the condenser and is discharged after condensation. The heating steam is condensed into water in the heating chamber and discharged. The solution in the tube is evaporated and concentrated under the heating of the heating steam, and discharged after reaching the requirements.
Steam jet heat pump has the characteristics of simple structure, stable operation and low price. Using a steam jet heat pump, the efficiency is equivalent to adding an effect evaporator.
Characteristics
Only a fraction of the evaporation energy has to be used in the form of live steam.
Low investment costs.
Retrofitting in existing plants is possible.
Suitable for various applications.
Variants
Increase in the number of stages to reduce steam consumption.
With or without salt separation.
Different preheating concepts.
Condensation of surplus vapour in mixing- or surface condensers.
| Performance Comparison for Different Evaporator | ||||
| Item | Single effect evaporator | multi-effect evaporator | TVR evaporator | MVR evaporator |
| Energy consumption | energy consumption is much higher than others, 1ton water will consume 1Ton steam in theory | comparatively energy conservation | Base on traditional multi-effect evaporator, one more effect added, but higher pressure steam driven needed | The most energy saving technology for evaporator, but 10-40kwh power consumption |
| Floor space | Small | large | large | small |
| Energy sources | steam & power, need steam pipe network and boiler | steam & power, need steam pipe network and boiler | steam & power, need steam pipe network and boiler, need high pressure steam. | electricity, don't need pipe network, all the close-loop circulation system |
| Automaticity | Semi automatic | Full automatic operation, continuous evaporation | Full automatic operation, continuous evaporation | Full automatic operation, continuous evaporation |
Working principle drawing
Our workshop and client's installation
