VACUUM SYSTEM
producer of soap plants
— VACUUM SYSTEM —
Vacuum Systems for bar soap drying plants
In dryer systems, the residual pressure must be lower than atmospheric pressure. For this feature of theirs they are called vacuum systems.
The part of the system that maintains the residual pressure at the desired levels is called the vacuum system.
The initial evacuation of the air from the system is carried out by means of a liquid ring vacuum pump. During normal operation, the same pump continues to eliminate any non-condensables that find their way into the installation.
The vapours released by the soap must be condensed in order to maintain the preset residual pressure levels. The condensation temperature determines the residual pressure of the installation, which in turn determines the temperature of the dry soap.
The traditional vacuum system consists of a vacuum pump, which draws in air and other non-condensables, and a barometric condenser, which condenses the vapours using water from the cooling tower.
The temperature of the tower water is limited by local climatic conditions (wet bulb temperature) and this affects the performance of the system. To overcome this problem, steam ejectors (Venturi tubes) are used to produce a vacuum upstream using the engine steam. The motor steam must be condensed in the Barometric Condenser together with the vapours released from the soap.
Ejectors are the main consumers of steam in dryer installations that require them.
The water in the tower is in contact with the soap carried by the vapours and, because of this, becomes increasingly contaminated, to the point of requiring water replacement and tower cleaning.
The Soaptec Group provides a Barometric Condenser which uses the recirculating water from the dirty circuit. This water exchanges heat with the clean water through a plate heat exchanger. The clean water comes from the chiller, which disposes of the heat taken from the dirty water.
In addition, the presence of the chiller allows accurate control of the condensation temperature and consequently of the soap temperature. Neither ejectors, and consequently the motor steam, nor the cooling tower and its associated water consumption are needed to operate these machines.
The Vacuum System doesn’t produce polluted water, as the condensate is recycled in the saponification process. In addition, not using steam significantly reduces the plant’s ecological footprint by shifting all energy needs to electricity, a renewable resource.