Design & Layout of Water, Wastewater and Residuals Pumping System

Example – Troubleshooting Problems with an Existing Facility

CASE STUDY #2

Problem:

  • Premature pump wear and damage to interior of pump casing
  • Pump suction piping arrangement not in accordance with good practice and ANSI/HI 9.6.6
  • Pumps: 7400 gpm each

Physical Modeling of Pump Intake

Solution:

  • Keep suction piping header and pump in as installed configuration
  • Eliminate eccentric reducer at pump suction nozzle
  • Revise suction elbow to reducing elbow with a ratio of 1.6 in/out
  • Add flow straightening grid
  • Conduct physical modeling to confirm

Results:

  • Modeling with subsequent field testing confirming model results
  • Improved pump performance
  • Increased pumping capacity approximately 1 mgd/pump
  • Premature wear mitigated

Modified Suction Piping