For multi-stage centrifugal pumps, how exactly should they be adjusted in order to achieve energy savings and reduced consumption?
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The multi-stage centrifugal pump used in this unit has 11 stages, with a rated head of 1600 m (should the rated discharge pressure be 16 MPa?) (1.5 MPa per stage), with a rated displacement of 300 m³. We regulate it using an electric valve at the outlet; usually, we monitor parameters such as the motor’s operating current, outlet pressure, and displacement. After stage reduction, there are 9 stages in total, but the management said that this reduction did not achieve the expected goals in terms of energy savings and cost reduction, and asked us to find out why I wonder, when it comes to the energy-saving and consumption-reducing benefits of centrifugal pumps, which parameter should be used to evaluate them? Is it not about achieving the highest pump efficiency? It is still at the lowest point in terms of power consumption (when power consumption is low, the displacement is relatively low as well). How does the performance curve of a centrifugal pump change after its stages are removed? Are there any relevant information or posts available on this topic? For multi-stage centrifugal pumps, how exactly should they be adjusted in order to achieve energy savings and reduced consumption?
The rated head is 1600m (should the rated discharge pressure be 16MPa? (1.5 MPa per stage); this statement is incorrect, as head is related to pressure difference and the density of the medium
The optimal condition for energy savings in centrifugal pumps is to have the outlet valve fully open, so that the pressure and flow rates can meet the process requirements. It can be adjusted via frequency conversion.
Whether energy can be saved depends mainly on the change in current before and after the reduction in stage count; if two stages of impellers are removed, significant energy savings should be achieved. I hope data from before and after removing the impellers can be shared
To save energy, variable frequency drives are necessary; controlling valves alone cannot solve the problem.
Frequency conversion probably isn’t something to take into consideration; after all, an inverter costs quite a lot of money
Why is it necessary to save energy and reduce consumption? Is it because the head is too high, or the flow rate is too high, or is it both?
If an investment can recoup its costs within five years, it is worth it – of course, this applies to large chemical companies; smaller ones might go bankrupt within five years. Search
Our facility uses 10KV/220KW motors driven by multi-stage pumps; we need to change the frequency. Does anyone here have experience with this? Are there any feasibility reports or relevant documentation available? What will be the effect of the changes, and does it need to replace the motor with an inverter-driven motor? I would appreciate the guidance of Haiyou experts. Thank you!
Circuit adjustment, either by cutting the impeller or by using an up-converter.
In our workshop, energy savings and consumption reduction are achieved by installing hydraulic couplings or cutting rotors in order to lower the power consumption of the motors.