The installation of a new two-stage air compressor replacing two single stage compressors at the end of their technical life has achieved significant cost savings with a Return on Investment in less than 2 years.
In Brief
Compressed air is one of the most convenient yet most expensive utilities in underground coal mining. Used for mine de-watering, stone-dusting, cleaning, ventilation and operation of mining equipment, compressed air is an essential and safe source of energy underground.
Centennial Coal, one of Australia's leading coal producers, used a comprehensive Measurement and Verification Audit to determine electricity savings achievable by replacing two single stage compressors having reached the end of their technical life with one modern two stage compressor.
To determine savings the actual efficiency of the old compressors was measured over a one week period providing the baseline for an assessment of the improvement potential.
Once the new compressor was commissioned, power consumption of all compressors was metered to determine overall savings.
Situation
The Myuna Colliery of Centennial Coal was looking to replace their current air compressors with a high efficient, power saving new air compressors and required approximately 1,667 l/s of compressed air at an average pressure of 800kPa. Before installation of the new compressors, air was supplied by two Champion VOC185 compressors and two Sullair LS25-350HAC Compressors.
The two Champion VOC Compressors supply air to the underground system through an air receiver and an air dryer whilst the two old Sullair Compressors were not connected to a receiver and supplied air directly to the underground piping system. Sullair was requested to assist with the analysis and develop the optimum energy saving solutions.
Results
- Return on Investment of less than two years
- Better security of supply
- Estimated total savings of 522 megawatt hours per year
- Annual reduction in carbon pollution of about 553 tonnes
