40% Energy Saving at a Cement Plant's Compressed Air Station in Henan

The client is a cement producer in Henan Province, part of a diversified industrial group. Over several years it had invested heavily in upgrading its kiln lines and restoring its quarries, and the cement lines’ overall energy indicators were already at an advanced level. The compressed air station, however, still had high energy consumption and low efficiency. The aim was to move from “the most efficient individual machine” to “the most efficient whole station”.

Cement plants use compressed air continuously for bag filters, pneumatic conveying, instrumentation and packing, so station efficiency has a direct effect on operating cost.

The station was rebuilt around two SIND SILVERLUBE-VPM series permanent-magnet variable-speed screw compressors, together with a station master controller and supporting equipment. The design combines three elements:

• On-demand supply. Variable-speed compressors follow actual consumption, so the station no longer produces surplus air or runs unloaded.
• Automated control. The master controller sequences the compressors and keeps network pressure at the required level.
• IoT monitoring. Operating data are collected continuously to support energy management and early fault detection.

After rigorous testing, the station met the Grade-1 energy-efficiency assessment standard (T/CGMA 033001-2018).

• 40.5% energy saving compared with the previous compressors.
• About 94 kWh saved per operating hour.
• About 815,000 kWh of electricity saved per year.
• About 465 t lower CO₂ emissions per year.
• Fewer equipment failures and lower maintenance and electricity costs.
• Better air quality and simpler station management, thanks to automated control.

For energy-intensive industries such as cement, the compressed air station is often one of the fastest places to cut energy use, because savings show up from the first operating hour.