Goals

• Validate whether the existing high and unstable operating pressure was genuinely required by production or was compensating for local pressure losses, transient demand, and control instability.
• Create a credible system baseline by combining flow, pressure, dew point, compressor amperage, compressor behavior, and observed process conditions.
• Understand how compressed air demand changes across distinct operating states: production, blockage and rapid turndown events, low-load off-shift periods, off-shift cleaning periods, and weekend non-production operation.
• Determine why a system with approximately 35 m³/min average demand and a measured range extending from very low off-shift flow to approximately 70–78 m³/min peaks was operating across such a wide pressure range.
• Identify how far system pressure could safely be reduced without transferring reliability risk to critical production equipment.
• Map supply-side behavior against actual demand-side processes so efficiency improvements could be implemented in a controlled sequence rather than as isolated corrections.
• Develop a practical roadmap based on a continuous optimization principle: Improve Demand → Adjust Supply → Verify → Repeat

Challenges

• A major loss of effective pressure control was observed. System pressure operated across approximately 7.5 to 9.3 bar, indicating that the compressor station was not maintaining a stable, narrow operating band.
• The two 110 kW VSD compressors appeared to carry a large share of the load without a clear one-active-trim / one-standby strategy. At times, the VSD compressors appeared to chase instability rather than smoothly trim demand.
• The three 90 kW fixed-speed compressors did not appear to follow a clearly defined and predictable base-load rotation strategy. Compressor capacity was often brought in reactively.
• The installed compressor system was very large relative to several operating states. During low-load and weekend periods, a 110 kW VSD compressor was being used to support a demand far below its preferred operating range.
• The plant contained major transient demand events. Most significantly, four of the six dust collectors use the same type of pulse-air arrangement as the unit observed producing an approximately 5 bar pressure collapse, from around 8 bar to around 3 bar.
• Local process restrictions were found around critical sorting equipment. Pressure losses of approximately 0.5 to 1.5 bar were observed or suspected between the main supply and the pneumatic valve blocks.
• Compressed air was used for manual cleaning at elevated pressure without clear local regulation, creating artificial demand and making total consumption sensitive to system pressure.
• Conveyer belt Blockages and rapid production changes created sudden changes in compressed air demand that propagated back toward the compressor station.
• The plant had several different operating states, but the compressor control strategy did not appear sufficiently adapted to those day types and demand conditions.

Discovered Potentials

• The system operated with an average flow of approximately 35 m³/min and an estimated average compressor power of approximately 310 kW, corresponding to an average specific power of approximately 8.86 kW per m³/min or 531 J/l.
• A controlled reduction toward approximately 6.5 bar indicated a projected annual saving of approximately €15,900–€21,000/year, depending on the final validated operating condition.
• A controlled reduction toward approximately 6.0 bar indicated a projected annual saving of approximately €20,300–€26,800/year.
• Correcting weekend and very-low-load operation indicated an additional opportunity of approximately €5,600/year, primarily by avoiding use of a 110 kW VSD package for a very small non-production demand.
• The practical combined first-stage opportunity was estimated at approximately: €20,000–€32,000/year‍
• Four major dust collector systems represent a potentially serious demand-side optimization opportunity. Their pulse demand may be contributing not only to direct air consumption but also to the plant-wide need for elevated pressure and a wide control cushion.
• Leakage is believed to be relatively low, at approximately 2–3 m³/min against an average demand of 35 m³/min. This represents roughly 6–9% of average flow, with a practical leak-reduction opportunity estimated around €5,000–€10,000/year, depending on what portion can be sustainably removed.
• Manual cleaning represents an opportunity to reduce air consumption through local pressure regulation, improved nozzles, operating discipline, and separation from unnecessary high-pressure supply.
• Desiccant dryer operation can potentially be optimized by reviewing the need for approximately −40 °C pressure dew point versus a less energy-intensive target such as −20 °C PDP, where process and freeze-protection requirements allow it.
• Critical sorting equipment showed potential for local piping improvements, reduced pressure loss, and strategically placed local storage. Correcting those constraints may allow lower plant pressure without compromising machine performance.

The report established a strong business case for treating compressed air optimization as a continuous system process rather than a one-time project: Optimize Demand → Re-tune Supply → Measure → Verify → Repeat

The broader realistic improvement potential, including additional demand-side work beyond the first-stage pressure and weekend actions, is estimated at approximately: €35,000–€60,000/year with higher technical potential possible where dust collector pulse demand, cleaning practices, local pressure restrictions, dryer operation, and remaining non-productive demand are successfully engineered and validated.

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