Distribution Optimisation
Distribution optimization focuses on three key areas:
Unintended leaks
  • Refer to leaks that exist that are unknown to management and also fully avoidable
  • These leaks are a significant source of wasted energy in an industrial compressed air systems
  • Losses of 20 – 30% are not uncommon in plants that have not been well maintained
  • These leaks are typically encountered at couplings, hoses, tubes, fittings, pressure regulators, pipe joints, disconnects and thread sealants
  • A 1/16 inch hole (@100 psi) will result in losses of approximately 6.5 scfm – which translates into yearly losses of R12,000 (assuming 24 / 7 operation)
  • Compressed air systems degrade over time and regular maintenance and servicing is required to avoid these losses
Intended leaks
  • Refer to leaks that exist that are actually known to management and while not fully avoidable can be minimised
  • These leaks are also a significant source of wasted energy in an industrial compressed air systems
  • These leaks are typically encountered at condensate traps / drains, some filter types, blower and nozzles
  • Many options exist to replace the above items with more efficient types and payback periods (justifying the change) are relatively easy to calculate
  • The most obvious opportunity requires replacement of timed drains with zero-loss drains
 
Condensate removal method Characteristics
Manual operation
  • Operators manually open values to discharge condensate
  • Effectiveness depends on people involved
  • Leads to losses because air escapes when valves are left open to drain
  • Also can lead to reduction in compressed quality if drains not opened regularly
  • Unreliable
Level operated mechanical float
  • Use a float connected to a linkage
  • Require maintenance
  • Prone to blockage from sediment
  • Prone to getting stuck in open position (leak air) or
  • Prone to getting stuck in closed position (does not allow condensate to be drained)
  • Inverted buck traps require less maintenance but will waste air on continuous basis
  • Relatively cheap investment
Solenoid operated
  • Timing devices that open for pre-determined amounts of time
  • Need to be set optimally, else results in excess air loss (open too long) or condensate build up (open too short)
  • More expensive investment
Zero-loss traps
  • Have a sensor or float level that operates a valve to maintain the condensate level in the reservoir below a high point
  • Wastes no air
  • Can be reliable but blockages from sediment build up must be monitored
  • Most expensive upfront investment
Pipe design and layout
  • Incorrect piping can lead to effective losses in the compressed air system
  • As a rule of thumb, a 2 psi pressure drop requires a 1% increase in the compressor energy
  • Avoidable pressure drops occur due to:
    • Incorrect pipe diameter
    • Length of piping to end use
    • Use of T and 90 degree joints
    • Other constrictions built into distribution network