Water boils at ≈100°C at atmospheric pressure ≈1 barA, at lower pressure the boiling temperature decrease. In vacuum, residual pressure of approx. 0,04 barA water boiling point is ≈30°C.
Boiling temperature has an important role in chemistry. Lower temperature means lower decomposition risk, lower encrustation, lower energy consumed.
n our Vacuum Evaporators, a liquid ring pump combined with a Venturi ejector provides vacuum. The required heat and cold side of the process, are provided by the heat pump circuit: 1 electrical kW = 4/5 thermal kW.
The contaminated water enters in the first vessel of the machine: absolute pressure ≈0,10 barA and the boiling temperature ≈42°C is reached thanks to hot coil of heat pump circuit. Steam produces in the first step, moves inside a coil in the second effect vessel, where the absolute pressure is ≈0,06 barA and boiling temperature ≈32°C.
The water steam coming from the first effect condensates inside the coil of the second effect and transfers energy at the contaminated water. Second effect steam is condensad by cold coil of heat pump circuit. The condensed steam is continuously and automatically collected from both effects.
The structure of our Vacuum Evaporators based on heat pump combined with vacuum technology, allow wide variety of liquid treated, high degree of concentration and significantly low energy consumption. Less than 100 Watt-h for 1 liter of water, for treatment of acid, oil, pigments, waste galvanization, radioactive fluids, pharmacology, food, toxic, etc...
These evaporators work in a continuous cycle without presence of operator, as they are equipped with devices which ensure a completely autonomous and controlled operation.