Air compressor station selection

I. Overall Equipment Selection: Select an energy-efficient compressor with a low power-to-weight ratio. Choose a suitable compressor type based on the specific gas volume range, fluctuations, and intermittent gas usage. Note that when there are more than four compressors, it is not recommended to use variable frequency drives (VFDs) for all or too many, to avoid energy loss and unnecessary investment.

II. Post-processing Equipment Selection: Currently, there are many types of post-processing equipment on the market, including refrigerated dryers, heated regeneration desiccant dryers, heatless desiccant dryers, and blower-heated desiccant dryers. When selecting these devices, parameters such as power consumption and gas consumption should be comprehensively considered to rationally select energy-efficient post-processing equipment. Furthermore, VFD-controlled post-processing equipment should be the preferred option because it can adjust its operating status according to actual needs, thereby achieving efficient energy utilization.

III. Piping Selection: Right-angle bends in pipelines increase flow resistance, create additional work points, and lead to gas impact and increased local pressure, causing the compressor to operate at high pressure for extended periods and easily unload. Optimizing pipeline connections can significantly reduce energy loss. An improperly routed air pipeline can lead to significant pressure loss, requiring a higher air pressure supply. Piping design should meet flow and pressure requirements, minimizing pressure loss by reducing the use of bends, valves, and reducers. Ideally, the overall exhaust pressure loss from the unit to the terminal should be controlled within 10%.

IV. Air Tank Selection: Generally, air consumption in thermal power plants, such as ash removal and conveying, fluctuates, potentially requiring screw air compressors with aftercoolers to discharge saturated compressed air. An air tank and pre-filter should be installed before the dryer. The air tank should be placed in a cool, shaded location and effectively drained. The air tank capacity needs to be determined based on compressor output and air consumption variations. Insufficient air tank capacity often leads to large pressure fluctuations, causing frequent compressor loading and unloading, wasting energy. Increasing the air tank capacity can extend unloading time, reduce unloading power consumption, and achieve energy savings. Frequent system start-ups and shutdowns can also occur. Effective air volume peak shaving can avoid frequent start-ups and shutdowns of standby units.

V. Compressor Waste Heat Utilization: The compressed air generation process is complex and generates significant heat during compression, reaching over 100°C in oil-free compressors. In the electrical energy conversion, only 20% is used for compressed air power, while the remaining 80% is converted into heat; therefore, compressor waste heat utilization is highly valuable. By utilizing the heat exchange between the operating hot oil, hot air, and soft water, and then transferring the heat to the user's hot water supply, waste heat utilization is achieved. The heat energy can also drive lithium bromide chillers to produce chilled water for production use.