Water treatment facilities commonly use sand bed filters to remove solids from the processed water.  From time to time these are back flushed to clear accumulated debris and regenerate the sand bed for further use.  

Air is injected to the bottom of the sand bed to agitate the grains and allow quicker back pressure operation for minimum down time. 

Suitable units would be side channel, claw and dry running rotary vane compressors.

Product Recommendations:

ZEPHYR DLR / PICOLINO DTE / PICO DLT / DRUVAC DTA / MACRO DTB / BORA SAP /

BORA SAH / MARIN SSP