58.9% Efficient Compressed Air Station for a New-Materials Plant in Hefei

A new-materials manufacturer in Hefei was building a new factory and needed a compressed air station designed from the start for top-class energy efficiency. The goal was a high overall transmission efficiency for the whole station, from electrical input to delivered compressed air. Supply pressure also had to be stable for production equipment.

That meant looking beyond the compressors themselves. Station layout, power supply, ventilation and heat dissipation, air treatment pressure losses and the use of compression heat all had to be considered together.

The station was designed to T/CGMA 033002-2020 (compressed air station energy-saving design) and GB 50029-2014 (compressed air station design). Compressors were selected against GB 19153-2019 energy-efficiency grades.

• Base load: one 150 kW SILVERLUBE series fixed-speed screw compressor.
• Variable load: one 100 kW SILVERLUBE-VPM series permanent-magnet variable-speed screw compressor. It tracks demand fluctuations.
• Low-loss air treatment: post-treatment equipment was configured so that the pressure drop to the supply end is only about 0.5 bar, while still meeting air-quality requirements.
• Heat recovery: potential heat users in the factory were identified, and a SIND heat-recovery unit was fitted to each SIND compressor so that compression heat is reused instead of rejected.

The station was tested to the national Grade-1 energy-efficiency standard, with a measured overall transmission efficiency of 58.9% — about 7% above the Grade-1 benchmark.

After commissioning, the station was measured on site:

• 58.9% overall station transmission efficiency.
• About 0.5 bar pressure drop from the compressor outlet to the supply end.
• SIND heat recovery on both compressors for on-site thermal use.

Designing the new station around efficient compressors, a low-loss treatment train and SIND heat recovery delivered high efficiency from the first day of operation.