(If you want to know all about “zero discharge”, go to part 1 of the article).
FORMECO heat pump evaporators
Our vacuum evaporator has been designed to perform a low pressure and low temperature evaporation process, above 35º.
First, the energy from the evaporator is generated by a heat pump that also produces the energy needed to condense the vapors produced.
How does a vacuum evaporation machine work?
The unit consists of a boiling and condensation chamber inside which the contaminated solution is sucked by a Venturi type vacuum unit, generated by a suction pump.
The water pump, connected to a Venturi injector, generates the vacuum. At atmospheric pressure, water boils at 100°C. By decreasing this pressure, the air resistance decreases and, therefore, the boiling temperature decreases. By exploiting this physical phenomenon, the vacuum evaporator is able to boil water at over 35°C.
The heat pump generates the necessary temperature for boiling and also the condensation of the vapor of the evaporated liquid.
The compressor compresses the Freon gas contained in the circuit (normally R 407 C) which heats it up to a temperature of about 70°C and circulates it inside the heating coil in the evaporation chamber or in the external solidary coil, depending on the liquid to be treated.
The inner or outer coil, installed at the bottom, heats the liquid being treated which, at a certain temperature, begins to boil. Water, in its liquid state, is transformed into steam.
The Freon is thus sent to the condensing coil, placed at the top of the evaporation-condensation chamber.
By means of an expansion valve placed inside the cooling coil, a pressure decrease is created which, consequently, produces a decrease in the Freon temperature.
The expansion of the gas, by the opposite effect of compression, induces cold. In this process, the vapors reach the top of the evaporator body and upon contact with the refrigerated surface of the coil, they condense.
The condensed water vapor is collected in a distillation tank. After a certain time, the residue deposited in the lower part of the kettle is super concentrated and can be discharged by means of a discharge valve. manual placed at the bottom of the evaporating body, by opening it, or by discharging automaticby means of an extraction pump.
The concentrated product will then be returned to the production process or treated according to current standards.
Please do not hesitate to contact our Technical Department for any questions you may have. We will be happy to advise you on which type of installation will best suit your needs.