ViST is Vacuum Shaker Screen Technology is to work with shale shaker to reduce drilling waste and recycle drilling fluids. This is technology developed by GN solids control, you can see the working video to understand clearly from GN website: http://www.gnsolidscontrol.com/vist-vacuum-screen

The unit is installed under the last screen of the shale shaker or installed externally of the shale shaker. It needs a air compressor to provide air supply for operation, most of the rigs will own one air compressor, no need to buy extrally. The air will create suction on the last screen of the shale shaker, reduce the liquid on the cuttings by 30% to 50%, separation of the fluids out of the cuttings.
It increased the recovery of useful drilling fluids, reduce the drilling cuttings volume, drying the drilling cuttings, so the vertical cuttings dryer working efficiency will be increased, the user will save a lot of the drilling waste treatment cost, and save more cost to prepare for new drilling fluids, so you can be benefit to use ViST vacuum shale shaker screen technology. Compared with the cost to use more drying shale shaker or drilling waste management system, the benefit to use ViST vacuum shaker screen is as below:

1)    Compact design, no need more space to install one more shale shaker or drilling waste management system, the result is to reduce the liquid 30% to 50% of the drilling cuttings for both WBM, OBM or SOBM
2)    Competitive price compared to use more equipments, including screw conveyor to transfer the drilling waste to drilling waste treatment system
3)    Less cost to transport the drilling waste if there is no on site drilling waste management system
4)    Less operation spare parts consumption, such as shaker screens
5)    No need electricity consumption to adopt such technology, can use the rig air compressor directly.