pumping system

[hvaclearner]

I would like to debate and arrive best pumping solution for this problem,The requirement is to pump water in 3 lakes located in at 1 km distance in a row for the irrigation purpose. The source of water is a circular tank around 15m high and there is common discharge(supply) pipe for all the lakes. All lakes are fitted with on/off valve and controlled by the water level in the lake. I want to design a pumping system which can able to supply the water in any lake depending on the on/off situation. There could be demand in one lake or in all lakes or all valves closed. I wish to go for multiple pumps running in parallel.Should I go for VFD or constant speed pump? What should be the control logic for efficent system? Please suggest.

 

[Artisi]

To make any real sense of the problem more info is needed, flow rates, pipe sizes, distances, static head, pumping periods.
Why have you nominated a multipump installation?

 

[BigInch]

VSD for irrigation is usually not an optimal solution.

The logic has been around for 5000 yrs. If the field needs water, water it, otherwise divert to another field, or turn it off.

VSD can more easily be justified, if there is a need for wide variations in flow. In irrigation work the flows can easily be held constant until the field has enough water, then switched off, or the same flow diverted to another field. When all fields have water, shut the pump down.

If you had to top off each lake and hold the exact elevations of the water's surface within +/- 1", a VSD could prove very useful.


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"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

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