Description of the operation of the Vacuum Sewage Drainage System
As soon as sewage reaches the required hight the pressure of the congested airspace in the level sensor pipe opens the control valve which activates the vacuum valve and through this vaccum (maintained by the system) it sucks the whole substances of the mine.
4 specific states of the operating cycle of the sump and the vacuum valve
Operational Description of the Vacuum Sewage Disposal System
The vaccuum valve
Vacuum valve consists of two main elements are :
– permeable medium
– control valve
The permeable medium house is kept closed with a spring in standstill position. Its upper part is separated by a rubber membrane from the pumping part which ensure that the vacuum space is isolated what is basically the operating part of the system.
When vacuum arises in the operating part then the piston will be raised againts spring pressure what provides free way to the outflowing liquid. In case of breakdown (blackout) when the vacuum falls under -0,25 /-0,3 bar tension then the power of the spring doesn’t let to open the valve which in case of recovery ensuring the quick emergence of vacuum in order to open valves nearest to the powerhouse. In the clean pipe system the appropriate level of vacuum can be formed.
There is a direct starting unit on the top of the operating part wherewith the permeable medium can be started at any time regardless of cyclic operation. Control valve can be connected directly onto the 63mm diameter level sensor pipe or upon request (can be conneted to different type of valves) it can be fitted with hose nozzle as well.
This unit is responsible for perceiving the level of the collected liquid and to let vacuum to the permeable medium in time what creates the open state of the vacuum valve.
When liquid leaves the mine then vacuum level and spring pressure in the valve are dropped off and then control valve closes the permeable medium. Closing time can be adjusted with an adjusting screw and with this we can control the required level of proportion of liquid and air. Free air necessary to operate the vacuum valve what gets into the system through a filter which can be placed inside our outside of the mine as well.
These two units are connected with a high resistant hose system. The plastic parts of both units are made of fiber glass Polypropylene metal and screws are made of A2 stainless steel material.
The mixture of air and sewage creates mousse and leaves the mine through a 90 mm diameter pipe and from this point it leads to the main pipe.
Diameter of the pipes are extended from 90mm to 250mm till reach the engine house. Consequently flow rate of the mixture is gradually reduced.
In the main pipe from specified distance there are level differences built in they called as „lifts” where at their lower parts at the end of the opening cycles sewage settles down and at the same time air can easily get through the next „lift” with lifting and forwarding collected sewage at that points.
By cycles repeatedly sewage is going forward until it reaches the container installed in the engine house.
Vacuum Engine House
Main parts of the vacuum engine house are : container, vacuum pump , slurry pumps, which are transmit sewage into the waste water treatment part of the plant.
Vacuum pumps are connected to the container and create vacuum and with this int he whole channel system at the same time.
When sewage reaches the right level in the container a sensor actuates the slurry pumps which is forwarding waste water into the wastewater treatment workshop of the plant.
Vacuum pumps and slurry pumps
Every unit in the vacuum engine house and the sewage management unit are computer controlled therefore the system can work with high plant safety and automatically.
Screen pictures of the computer controlled software of the engine house