Vacuum station: Outdoor
All the vacuum sewers are connected to the vacuum collection vessel installed at the central vacuum station, where vacuum pumps (lower picture) create the required negative pressure (approx. ? 0.6 bar).
The vacuum vessel can be placed inside or buried outside the vacuum station. Transfer pumps convey the wastewater from the vessel to the wastewater treatment plant or to an existing sewer.
The capacity and dimensions of the vacuum station are dictated by the particular requirements of the sewer system. Operation of the vacuum and transfer pumps is controlled through a PLC with the software designed to ensure optimum demand-driven operation.
A standard ?compact vacuum station? can be delivered prefabricated and tested for small sewer systems to service a small number of houses in villages or buildings on industrial estates. Individual design and construct services can be provided for vacuum stations for hundreds or thousands of houses and buildings.
Vacuum Station - Indoor
The Vacuum station is at the heart of the system. By the vacuum station it is created and maintained sufficient vacuum for the whole of the pipe network. It comprises:
? collection vessel
? vacuum pumps
? wastewater discharge pumps
? a control panel
One or more vacuum pumps are designed to operate automatically. The duty pump(s) starts when the pressure rises within the system to approximately ?0.45 bar and stops when the pressure has reached an operation level of approximately ?0.60 bar. Due to the automatic operation of the pumps within a small range of negative pressure power consumption is minimized.
All wastewater arriving in the collection vessel is pumped to the nearest public sewer. Level sensors in the vessel automatically control the wastewater discharge pumps i.e. when the level in the vessel reaches a pre-set high level the duty pump starts, and when the level falls to a pre-set low level the pump stops.
The capacity of the collection vessel is determinated by the volume of wastewater to be collected, the frequency of pump starts and the required vacuum ?buffer? volume. Various factory pre-built ?compact? stations for ease and speed of installation can be supplied. Different sizes of stations can be supplied depending on the number of sanitation fittings connected to the system or the number of vacuum valves installed. In addition, the total length of pipework influences the size of station required.
Smaller size vacuum stations consist of a PE vacuum vessel with the vacuum pumps installed on top of the vessel. A steel vessel is supplied with the larger size stations and both the vacuum and wastewater discharge pumps are mounted together on a steel frame adjacent to the tank. All ?compact? stations are supplied to site ready assembled for installation. Where larger vacuum stations are required the various components are supplied separately for installation in a project specific, tailored vacuum station.
- A Type PE70 ?compact? vacuum station with a black PE vessel
- A Type 360 ?compact? vacuum station with a blue steel vessel
