vacuum toilet system is applied to railway passenger coaches, vacuum
intermediate is recommended for the vacuum evacuation system. In this way, there is
no need to generate vacuum in bio digester tank, and the tank could have constant
normal pressure. The working principle of vacuum intermediate type evacuation system
is: Install a intermediate tank between toilet module and bio digester tank. In standby
mode, there is no vacuum in the bio digester tank and intermediate tank. When flushing,
vacuum generator (ejector) will temporarily generate vacuum in intermediate tank, then
the inlet pinch valve between toilet module and intermediate tank will open, sewage in
the toilet module will be sucked into intermediate tank by vacuum, and then the inlet
pinch valve will close. Then inflate compressed air into intermediate tank, the outlet
pinch valve between intermediate tank and bio digester tank will open after the setting
time, and then the sewage in the intermediate tank will be transferred to bio digester
tank. Then the flushing cycle is over.