1. Overview
The NZJAHPP series slurry pump is a high-pressure, high-head slurry pump specially designed for tailings applications. It is mainly used for long-distance transportation of ore slurry in various metal mines. The capital cost of centrifugal slurry pumps can be significantly lower than that of positive displacement pumps and diaphragm pumps. In addition, centrifugal slurry pumps can be used in series with multiple pump stations, which reduces the pipeline pressure level between pump stations and also means that thinner pipes can be used at lower cost. Centrifugal slurry pumps are used for tailings transportation, and the maximum particle size of the slurry can reach 100 mm, whereas piston pumps, diaphragm pumps, and positive displacement pumps require slurry particles smaller than 5 mm, which is difficult for mines to control. The ZNJAHPP series slurry pumps produced by Naipu can achieve a head of up to 100 meters per single pump, but this is not the most suitable operating point; considering wear and efficiency, the head of a single pump should be far less than the maximum head. At present, Naipu's NZJAHPP slurry pumps have been exported to major mines at home and abroad, such as those in China, the Philippines, Serbia, and the Democratic Republic of the Congo.
2. Design Features
2.1 Double casing design
This double casing design is important for high-pressure, high-head slurry transportation. The outer casing is designed to withstand all internal pressure, so even if the wetted parts are completely worn, there is no concern about structural strength.
2.2 Bearing assembly
We use imported TIMKEN bearings. The actual load borne by the bearing assembly can be designed according to requirements; for example, the 450NZJAHPP tailings pump has a maximum load capacity of 2000 kW.
The bearing operating speed can be designed according to requirements; grease lubrication;
2.3 Compared with the general-purpose NZJAH series slurry pumps, the pump body and pump cover are thicker. During the specific design process, our designers will also optimize the position of reinforcing ribs through finite element strength analysis.
2.4 More and larger pump cover studs. In particular, the studs specially arranged at the partition area are a distinctive feature of this series of slurry pumps.
2.5 When rubber liners are used, the design needs to be improved to prevent leakage and prevent the liner from being pulled out by water hammer; the peripheral sealing flanges of the front and rear liners should be thickened.
3. Naipu's Design Capabilities
FLUENT technology and EDEM technology have been applied to fully optimize the impeller, liner, and other components to achieve high efficiency and overcome localized wear. UG is used for 3D modeling.
3.1 Model establishment and mesh generation
• UG 3D modeling to extract the computational fluid domain;
• Hexahedral unstructured mesh generated with ICEM software.
3.2 Computational model
• ANSYS-FLUENT computational model software analysis;
• MRF solving under multiple reference frames, with RNG turbulence model;
• Momentum equations and continuity equations solved simultaneously using the SIMPLEC algorithm.
3.3 Head and efficiency prediction
3.4 EDEM particle motion trajectory / FLUENT discrete phase DPM
3.5 Full 3D structural design using the 3D software UG. Shell strength analysis uses ANSYS-FLUENT fluid-structure interaction calculation, with the static pressure distribution calculated by FLUENT used as the initial condition for strength calculation.
3.6 For large projects, we will carry out a 3D site layout based on the customer's existing mine layout, so that the customer can intuitively understand what the completed project will look like.
3.7 Equipped with a visualized PLC monitoring system, which enables operators to operate the tailings transportation slurry pump system more effectively and simply.
