Wuppertal / Herne, July 2020. The Wupperverband, based in Wuppertal, operates 14 reservoirs, eleven sewage treatment plants, a sludge incineration plant as well as flood retention basins and stormwater tanks in the river Wupper catchment area. At the Buchenhofen site in Wuppertal, a high-performance wastewater treatment plant ensures clean conditions. The sewage sludge that inevitably arises during the treatment of wastewater in Buchenhofen and surrounding sewage treatment plants is dried and incinerated in the adjacent incineration plant in an environmentally friendly manner. A new, turnkey pump system from SCHWING has recently been introduced to transport the sewage sludge and feed the incinerators.
SCHWING high density solids pump instead of trough chain conveyor
The trough chain conveyors previously used to transport the sewage sludge for drying and feeding the two incinerators have a high degree of wear due to their design and require frequent maintenance. For this reason, the Wupper Association decided to replace a trough chain conveyor with a sludge pump system with a two-cylinder piston pump. After intensive testing, the choice fell on a pump system from SCHWING
consisting of a sludge piston pump, a double screw feeder, a drive unit and a lubricant dosing system. The existing sewage sludge acceptance silo with a capacity of around 35 m³ was integrated into the system. The silo is connected to the two mutually operated incinerators via a 115 m long, insulated and stainless steel-clad conveyor line, which was also supplied and installed by SCHWING as part of the order. The automatic lubricant dosing system minimizes the frictional resistance by the metered addition of water at the beginning of the conveying section and thereby reduces the energy consumption for the conveying of the medium. The double screw feeder SD 250 was installed under the existing acceptance silo via a new transition flange. The task of the double screw feeder Marketing is to homogenize the pumped medium, here the sewage sludge, and to build up a prepressure for a continuous and controllable supply of the pumped medium to the sludge pump. This increases the filling level of the delivery cylinders, so that a high delivery rate is guaranteed even with highly viscous media. The KSP 10 HDV sludge pump with poppet valve system (STVE) achieves a maximum flow rate of 7 m³ per hour and only requires 15 strokes per minute. The hydraulic unit for driving the sludge pump and the double screw feeder was installed behind the existing acceptance silo and is driven by a highly efficient electric motor with an output of 55 kW. The entire pump system is connected to the central control room in the main building with the incineration plant and is monitored from there. Numerous sensors and carefully coordinated software, which enable the sludge pump system to operate fully automatically, provide additional security.
Low operating and maintenance costs of the valve system
The poppet valve system (STVE) developed by SCHWING is used to convey finegrained, pasty media such as sewage sludge. It is characterized by its excellent reliabilityand easy maintenance and has proven itself in a wide range of applications worldwide for decades. For the maintenance of the poppet valves, the pressure housing can simply be folded aside after loosening the screw connection. Then the valve disc and the valve seat can be rotated depending on the degree of wear or replaced if necessary. The low
maintenance requirements of the SCHWING poppet valve system and the simple replacement of wearing parts ensure low operating and maintenance costs.
After commissioning the new plant, the Wupper Association is now using a total of 17 SCHWING sludge pump systems at the Buchenhofen site in Wuppertal/Germany. For operations manager Dirk Salomon and his colleague Dirk Nuendel (responsible for electrical engineering), the decisive factors for this high number are the reliability, simple maintenance and long service life of SCHWING pump systems.
The Wupperverband celebrates its 90th birthday this year. Then, as now, the association is centrally responsible for the water management tasks of the towns, communities, districts, water supply companies, industry and trade in the Wupper area. It is responsible for the maintenance of around 2,000 kilometres of rivers and streams.
Sludge pump KSP 10 HDV
Output 0.7 – 7.0 m³ / h
Output pressure max. 150 bar
Strokes 1.7 – 15.6 per min.
Valve system Poppet valve system (StVE)
Double screw feeder SD 250 – 2800
Output max. 7 m³ / h
Output pressure max. 6 bar
Length 4,520 mm
Entry opening 2,800 mm
Drive unit EHS 400
Drive power 55 kW
firstname.lastname@example.org – www.schwing.de
Heerstraße 9 – 27
Deutschland / Germany
Photos (Copyright: SCHWING GmbH)