Sludges of differing densities and temperatures
Built N300-36 transfer pumps in record time, measuring 11 m in length, weighing 7 tons
Machined from a 1.7 ton piece
of tool steel with precision
down to 0.2 mm, the rotor
is 6 m in length and
weighs 0.7 tons
Reduced labor costs
Thames Water operates one of the UK's largest sewage treatment plants. Located in West London, it treats sewage for around 2.1 million residents. A plant of this size requires both pumps and service levels that are extraordinary. SEEPEX delivered both.
Originally built in the 1930s, the Mogden sewage treatment plant has undergone major expansions over the decades to keep up with exploding population growth.
SEEPEX has a longstanding relationship with Thames Water, having worked with them in framework agreements for over 20 years to reduce the cost of ownership of progressive cavity pumps and improve the efficiency of processes where progressive cavity pumps are used.
SEEPEX were approached by an EPC contractor with a pump duty to transfer 180 m³/h of 6-8% dry solids thickened sludge to a sludge dewatering facility 18.5 km away.
This was no small challenge given the distance, capacity and the %ds content of the sludge to be transported. Various pump technologies were reviewed. Some were not able to handle the high dry solids concentration, while others required either multi-stage pumping or had the potential of generating high pulsation spikes.
The selected pumps could easily handle the 6-8%ds thickened sludge and had the ability to pump the 18.5km without any need for intermediate pump stations. In addition, inverter drives were fitted so that the large volume of sludge in the discharge pipework was accelerated slowly on start-up, thereby preventing pressure spikes.
“The extraordinary SEEPEX N300-36 long distance transfer pumps were a milestone in technological development and the biggest progressive cavity pumps in existence at that time in terms of both weight and length at 7 tonnes and over 11 metres long respectively, and fitted with 250 kW drives.”
Head of Mechanical Development & Innovation Strategies
A SEEPEX inter-departmental project team of 30 people worked together to design, manufacture and deliver these giant pumps in record time.
Almost 20 years after their installation in 2003, these gigantic pumps are still in operation, which is a testimony to SEEPEX’s workmanship, product quality and service excellence.