Smart Air Injection including compressed air connections and lubricant injection points .
The wastewater board operates the Hetlingen WWTP northwest of Hamburg , Germany . Serving more than 40 towns and communities , the Hetlingen plant treats more than 31 million cubic metres of wastewater per year and processes about 46,000 Mg of sludge per year , which is anaerobically stabilised , dewatered in centrifuges and pumped into silos . After anaerobic stabilisation , the digested sludge is dewatered in centrifuges in a separate building and then falls through a hopper into the pump cellar . From there , it was previously pumped by two piston pumps to two silos located 60 metres away and 30 metres higher . The dewatered sludge is then trucked to an off-site incinerator for thermal recovery . When the centrifuges were replaced in a planned rebuild , the piston pumps were found to be undersized . In addition , maintenance requirements and energy costs were very high .
silos . The result , as envisioned by the plant operators , was a system that would minimise maintenance and energy costs , as well as downtime for servicing . The goal was to significantly reduce the total cost of ownership ( TCO ) in direct comparison to installed piston pumps . In addition , the wastewater authority wanted a much more flexible system that would be suitable for future upgrades . As the centrifuges for dewatering had already been ordered , a quick solution had to be found to transport the 5 - 15 m ³/ h of sludge to the two silos within the existing infrastructure and without interrupting operations .
With SAI , SEEPEX , the world ’ s leading specialist in progressive cavity pumps , pump systems and digital solutions , has launched a customised system solution .
Hetlingen WWTP turned to SEEPEX when it needed to improve its solids handling technology following the replacement of centrifuges and feed pumps . The main challenge was to find a new thick sludge conveying system that would fit into the existing infrastructure along with the replanning of the thickening sludge
Issue 69 PECM 81