Energy-Saving Retrofit of Compressed-Air Station at Southwest China Aluminum Smelter

Background: The air-compressor station serves all pneumatic equipment of an aluminum smelter with large and sharply fluctuating air load. Original units ran under long-term high load with heavy idle loss, frequent high-temperature trips in summer, and moisture in compressed air that damaged pneumatic components.

Solution: Upgraded to permanent-magnet variable-frequency screw units with intelligent joint control that allocates load according to consumption curves. High-efficiency refrigerated dryers and precision filters control dew point and cleanliness. Pipe network optimized to reduce pressure loss. Waste-heat recovery feeds factory heating.

Results: Comprehensive power saving of about 25%, pressure fluctuation controlled within ±0.02MPa, and high-temperature trips eliminated. Dried air source cuts pneumatic-equipment failures, with maintenance workload reduced by about 30%.