Waste Reclaim

During Silicon ingot manufacturing, large quantities of water must be used to cool tools and silicon surfaces, to act as a lubricant and to remove the resultant silicon fines. SIlicon infused wastewater occurs as a by-product of silicon ingot manufacturing. The limited availability of waste disposal sites and disposal space means it’s important to manage waste efficiently and implement reclamation systems to decrease costs. Pall’s advanced reclamation solutions help silicon ingot manufacturers better manage wastewater to control process performance requirements, minimize machine fouling and sediment buildup, and reduce operational expenses.

Pall introduces a new generation of fully automated separation systems for the reclamation of water and silicon sludge from the spent grinding/sawing water.

FIrst the wastewater travels to a collection tank after being used for cutting/grinding tools. It then travels to a buffer tanks and then to the main unit of the system. The heart of the system is a dynamic membrane filtration (MF) unit combined with physico-chemical treatment of the concentrated silicon. The systems clarify the contaminated process water and typically 90 to 95% of the contaminated process water is perfectly clarified ready for re-use and pumped back to the cutting/grinding tools. The remaining concentrate may be discharged, mixed with other wastewater streams, or subjected to additional treatment to meet discharge regulations or to de-water the silicon debris. Other options are available on request. Pall has over 20 systems running successfully throughout the world treating a variety of silicon infused wastewater from 3 to 33 m³/h (13-145 GPM).

Benefits:

• Re-use up to 95 % of spent process water as high quality process water
• Reduce wastewater discharge volumes and disposal costs
• Improve cutting/grinding performance by controlling process water specifications
• Reduce machine fouling and uncontrolled sedimentation in pipes, tanks and sinks and other components 
• Reduce chemical hazards due to silicon-water interaction by controlled pretreatment of spent process water
• Collect de-watered silicon debris having very little chemical contamination, as feedstock for silicon re-use.

Contact us for more information about Pall filtration technologies for water reclamations applications.