Operating point of Pump

 Best Efficiency Point (BEP):

The Best Efficiency Point (BEP) is the point of highest efficiency of the pump. It is not possible to completely convert kinetic energy to pressure energy. Some of the energy is always lost.

The operating point will always be where the system curve and Head flow curve intersect. Operating the pump beyond the BEP not only decreases its efficiency but also subjects it to mechanical and hydraulic problems. For centrifugal pump, an increasing system resistance will reduce the flow of pump.

Therefore, the pump is recommended to operate in a range of ±15% around the BEP. The pump should never be operated at a flow rate lower than 60% of the Best Efficiency Point. If we operate pump beyond BEP range, then excessive vibrations that can destroy its bearings. If we operate pump at a flow rate higher than 120% of the Best Efficiency Point, then cavitation will create inside the pump and that destroys its impeller.

Energy conservation in Air Compressor

Reducing Compressed air leakages in the plant and thereby reducing running hours of air compressors on load

Description of Existing system and its operation- Leakage test was conducted and leakage percent was found to be around 35%

Description of Proposed system and its operation-
In a good air system, the permissible air leakage is 10% only and hence around 25% leakages need to be plugged.
 

Energy saving calculations:     Average Unload time 9 Seconds Average load time 15 Seconds Percent leakage= Average load time/(Average load time + Avg. Unload time) x 100     0.375   Percent leakage= 37.50%     This leakage is high and should be brought down.   Avg. Power consumption of bigger air compressor 58.5 on load and 39.1 on un-load for screw comp no-4   Air leakages which should be plugged 27.50%   Average power which can be saved per annum by plugging leakages for 24 hrs of its use per day. Assuming comp runs on load is around 60% of total time 28041 Units       Annual Energy saving potential 28041 units   Annual cost saving @ Rs. 8/Unit 224326   Annual cost Saving in INR INR 224326/-   Investment INR 5000/-   Simple payback period 0.02 Year