Get to know sewage dry well pressure pumping by Hydro-Vacuum S.A. (TSA, TSB, and the newest TSC)
One of the main and most burdensome problems appearing in the sewage pumping installations is the presence of solid particles in them. Regardless of the kind of applied pumps there will always be the risk of clogging the hydraulic system of pumps, and as a result there will be a breakdown in the pumping station. Solid particles transported by sewages like strings, pieces of cloth, bandages, etc. are especially troublesome.
Application of pumps with so-called “non-clogging impellers” with free flow will always be related to a drop of the hydraulic efficiency, which as a result will lead to an increased cost of operation of the pumping station. Application of pumping stations with separation of solid bodies allows for effective avoidance of the aforementioned and other problems, which will appear in the sewage pumping stations.
A sewage pumping station is nothing else than a pumping station with separation of solid bodies, which allows for dry well pressure pumping of the separated solid bodies to the pressure pumping pipeline. Application of a sewage dry well pumping stations allows for avoiding clogging of the pump impellers, increasing of the hydraulic efficiency and what follows, diminishing of the operation costs.
Principle of operation
In a classical pumping station (wet) the sewages directed through the gravitational channel flow directly to the retention tank. In pumping stations with separating of solid bodies, the sewages flow to a dry well pumping station tank, which is placed in a dry chamber and then are redirected to the particular separators. From the separators, the cleaned sewages which do not have solid bodies, sediments and dragged elements flow gravitationally through the hydraulic elements of the pumps to the dry well pumping station tank.
In case of operation of any of the pump, the sewages flow only to the separator connected to the non-operational pump. The present sewage levels in the dry well pumping station tank are monitored with a probe. Upon receiving a signal on reaching the preset sewage levels in the tank, the protection-control device starts up or switches off relevant pumps.
The started up pump sucks the pre-cleared sewages and pumps them to a separator. The energy of the pumped sewages agitates the solid bodies located in the separator, directing them to the pressure pumping pipeline of the pumping station. The excessive pressure generated during pumping closes the back flow of the sewages to the dry well pumping station tank.
In the course of the pump operation cycle the sewages flow to the tank through the second separator and hydraulic system of the not-operating pump. Having reached the lower preset sewage level in the tank the pump is switched off automatically. The separator construction causes that the pumping station can operate continuously, in a manner not requiring introduction of additional operations of removal of the accumulated impurities.
During each starting up of the pump a “self-cleaning” of the separator is done. The hydraulic system of the pumps that does not have direct contact with the solid bodies, and especially with the dragged bodies dragged is not exposed to clogging. The both pumps are started up automatically alternately, which extends durability and effectiveness of system operation, moreover it allows for maintenance with no necessity of stopping operation of the dry well pumping station.
The system differs substantially from a traditional pumping station with submersible pumps. A dry well pumping station is a pumping station with the pumps located in the dry chamber. The sewages flow in the closed chambers, which minimalizes their impact on the environment and especially on emission odours outside. A dry well pumping station operates in the service free way and thanks to the solid body separation the pumps are not exposed to clogging, because they pump sewages separated from larger impurities. Thanks to the closed, tight retention chamber, impact of the dry well pumping station on the environment is limited to minimum.
Servicing of the dry well pumping station is safe and relatively “clean”, thanks to the construction of the dry well pumping station itself and the fact that access to the particular elements is from the level of the chamber, in which the device is located. Small capacity of the dry well pumping station tank results in a short pump work cycle, thus increasing the frequency of switching off the pumps, which diminishes the time of sewage retention and at the same time prevents starting of the process of sewage decomposition inside the dry well pumping station.
The pumps applied in the sewage dry well pumping station are made by Hydro-Vacuum S.A. featuring the IP68 motor protection level - it is not a fan motor (which creates the noise nuisance) - as a standard the Hydro-Vacuum S.A. pumps, depending on the selected operation point for the dry well pumping station near the device, generate the noise intensity on the level of 50-60 dB. The dry well pumping station is constructed in the underground tank, which substantially reduces the noise intensity. To compare a modern car with a combustion engine generates ab. 50 dB of noise. Thus on the surface, with the closed manhole cover the pumps do not react adversely on the environment.
The dry well pumping stations by Hydro-Vacuum S.A. are provided with a certificate issued by an independent accredited laboratory for compliance with standard PN-EN 12050-1:2002 “Sewage pumping stations in buildings and their environment -- Construction principles and testing -- Part 1: The pumping stations of sewages including faeces”. The TCS series products are frequently mounted inside buildings, which clearly testifies their small reacting on the environment.
The TCS series dry well pumping stations, due to the operation process do not require setting of an environmental reacting zone, they are completely safe objects for the environment because they do not emit burdensome fumes and screenings.
Advantages of sewage dry well pumping stations:
- limiting to minimum the occurrence of breakdowns depending on blocking pumps with solid bodies occurring in sewages (long and dragged solid bodies),
- minimizing of the risk of damage of the hydraulic system of the pumps (separation of the solid bodies before the pump),
- improvement of the comfort of performed maintenance and repair works thanks to installation of the dry well pumping station in a dry chamber,
- diminished tank capacities prevent decomposition of the sewages and emission of foul odours (frequent starting up of the pumps),
- smaller power consumption, therefore substantial diminishing of costs of electric power in relation to a pumping station,
- possibility of installing inside a building, which is virtually impossible for the pumping stations,
- the dry well pumping stations, due to the operation process, do not require setting of an environmental reacting zone, they are completely safe objects for the environment - which cannot be said about pumping stations constituting the source of foul odours.
Disadvantages of sewage dry well pumping stations:
- increased investment expenses at a unit purchase as compared to a pumping station
- increased requirements concerning the tank diameter to mount a dry well pumping station in case of locating it out side a building in relation to a pumping station (minimal diameter of a dry well pumping station - 1500 mm, pumping station - 1200 mm)
- minimal pressure pipeline diameter DN80.