Collect hold and transfer system and STP operation Flashcards
Operation of the STP
Raw sewage via macerator enters coarse screen-removes large particles.
Waste enters aeration compartment, aeration diffuser passes oxygen through waste.
Undigested waste sinks to bottom, digested floats-separating.
Air lift pump transfers waste to settlement hopper, heavy sludge sinks to bottom effluent floats on top.
Effluent weirs across to chlorine tank, weirs across again to collection tank.
Grey water added to dilute chlorine and disinfecting grey water- discharged overboard.
Sludge in hopper returned to aeration compartment via an air lift pump.
Operation of Collect hold and transfer system
A fully automated system whereby sewage is collected in tanks with a storage capacity of 12 days.
The sewage is collected by means of a vacuum.
Pumps draw vacuum from first tank which has a storage capacity of 1 day.
Tank is connected to WC.
Level switches ( A combined transfer/discharge pump) transfer the sewage to larger tanks where it remains until discharged.
An ejector circulates the sewage between tanks preventing it from becoming anaerobic digestion.
The vacuum pumping system transfers the sewage to shore when alongside.
