Zero Discharge Spent Coolant Recycling

Description of Process

1. Currently most metalworking facilities purchase concentrated coolant that they dilute with fresh water

2. Coolant is used as lube for forming/machining/casting

3. Using a filtration and/or centrifugation system on the spent coolant allows the facility to recycle some of the coolant.

4. Processing the unusable waste coolant with a R-Vap Mechanical Vapor Recompression evaporator creates distilled water that can be reused and a concentrate that can be blended with waste fuels.

Benefits

• Reduced concentrated coolant costs
  • Buying coolant is expensive. With this process our clients ultimately recycle 35-45% of the spent coolant. The recycle percentage is based on the glycol levels in the coolant.
• Lower operating costs
  • The R-Vap MVR evaporator processes waste coolant at ~$0.01 per gallon.
  • Reduced fresh water costs. 90-95% of the waste coolant is converted to distilled water. This distilled water can be used for diluting concentrated coolant.
  • Reduced waste fuel costs. Most metalworking facilities use waste oil to fire their furnaces. Blending the concentrated waste coolant with waste oil reduces the amount of waste oil that needs to be purchased.
• Able to handle tramp oil
  • Oils and other various liquids in the plant can make it into the wastewater stream even in plants that have the best intentions of keeping their wastes separate. The R-vap unit can handle most waste liquids for the metalworking industry. These liquids will end up in the waste concentrate.
• Zero discharge
  • By recycling the byproducts as make-up water and waste fuel this process is zero discharge.

Applications for coolant from

• Die castings
• Forming and drawing
• Stamping
• Powder metallurgy