A pumping system designed to separate solids and pump waste water over longer distances holds the key to providing acceptable sanitation to rural villages and sparsely inhabited areas where, until recently, the bucket system and pit latrines were the only alternative.
Designed and developed by KSB Pumps and Valves, the Ama DS allows treatment of waste water to be undertaken further from treatment plants and makes it viable to collect waste water from larger collection areas for treatment at centralised plants.
According to Hendrik Enslin, KSB waste water projects and applications manager, the Ama DS system enables wider and more cost effective collection of waste water and paves the way for the development of sanitation systems in rural areas or areas where sanitation was not deemed possible due to unsuitable geographical location or where gravitational systems were not possible.
Large area coverage
“The genius of the system is the ability to immediately remove solids from the system and separate it from the water. This enables pumps with smaller free passages to be used and as a result allows the system to pump the water over much longer distances than previously possible. In addition, with the solids removed, there is nothing to impede or block the impellers etc and this allows for a far more reliable system and cleaner, more hygienic pumps for ease of serviceability. Once solids build-up to a pre-determined level some of the processed waste water is then used to bypass the pumps and flush the solids to the treatment plant.
“This effectively frees municipalities or communities to pump waste to more distant treatment plants or to establish centralised plants that can be shared by many different communities in a region. We are hoping that this will play a significant role in bringing sanitation to all parts of the country,” says Hendrik.
In typical KSB fashion the company has used technology to overcome an age-old problem and provide configurable solutions that can be tailor-made to suit applications. Using smart level meters and trending technology the entire system can be managed to ensure the system is able to cope with varying demands throughout daily, weekly and even seasonal fluctuations.
Both water and solids levels are constantly monitored and purged as and when required. Inflow and outlet pumps are only operational when required and as a result the system uses less energy, which is an important consideration in far-flung areas. In addition, the Ama DS system is also well suited for applications in municipal and industrial waste water transport, drainage of hotels, hospitals, campgrounds, low density housing projects etc. Systems are available to handle anything from 6-200 cubic metres per hour.
Besides the obvious benefit of providing sanitation in far flung and rural areas, the system also provides a solution that is more efficient than traditional pumping systems, is more reliable as a result of solids being removed before entering the pumps, less downtime as a result of less wear and blockages, cleaner and safer operation and less maintenance.
How it works
Hendrik explains that the patented solids separation system removes solids and temporarily stores it in separators. Only pre-treated waste water not containing coarse solids flows through the pumps. The pre-treated waste water is pumped through the solids separators in the opposite direction and carries the solids out of the separators and into the discharge line. Through this process the solids separators and pumps are cleaned and ready for the next inflow phase.
“During the design stages our experts also paid great attention to maximising operating reliability in order to keep future maintenance to a minimum, thus reducing the overall costs. Necessary servicing work can also be carried out while the equipment is in operation and service personnel work in hygienic working conditions. Maintenance to the externally installed solids separators can be conducted very easily, quickly and without shutting down the system.