NETZSCH Lanzhou Pumps Co.,Ltd.                           

SP pump NM090SP08S48Z for sludge cake conveying in a WWTP in China.

This WWTP is one of the largest sewage plant in China, The plant is built in two phases, at present the first phase of construction have been Completed, the daily capacity of disposal has reached 0.64 million tons, in which 2 sets of NETZSCH pumps for sludge cake is employed; The second phase of construction is going on and 8 sets of NETZSCH pumps for sludge cake have been chosen, which will be installed before the end of the year.

in the first phase of the project, two big pumps type NM090SP08S48Z were used to convey sludge cake from the plant to the dock, and then to the cargo vessel, the horizontal distance was about 240m, the detail parameter as the following:

Medium conveyed:                       dehydrated sludge cake

Solid content:                              20～25%     

Temperature of medium:             10～30 °C
PH value:                                     4～10
Kinetic viscosity:                           Non-flowable
Flow rate:                                    8～20m3/h
Pressure of discharge:                   about 30 bar
Pressure of suction:                      Inflow
Shaft power required:                   55 kW, 2500 Nm

Pipeline for conveyance:                DN400, carbon steel

As the above-mentioned working condition, we selected pump NM090SP08S48Z, due to high solid content, the pump operate with low speed to maintain a longer life time of stator and rotor.

In order to reduce friction losses of pipe-line and improve conveying efficiency, a lubricating system was considered, it was that a small pump NM015SY08S48Z is arranged by the main pump and connected to outlet pipe-line, lubricating liquid was polymer solution, thus a thin liquid film was formed between inner surface of pipe-line and sludge cake, so the friction resistance declined greatly.