Chemical Treatment
Treatment by this method uses various chemicals to destabilize, de-emulsify, or absorb into the oil phase of a metal removal fluid, thereby allowing the water and oil phases to separate. Click for more details about the different methods of chemical

At a minimum, one storage tank, one processing tank, and one oil-sludge tank are necessary. A processing tank should be large enough to handle at least one average day of flow. If the system is being set up for continuous flow, a series of cascading tanks with at least a half- hour retention time per tank is necessary.

A small laboratory bench with a dedicated pH meter and calibrating buffer solutions, a magnetic stirring mixer, chemicals used within the process and pipettes for measuring chemical additions are all good to have on site. Truck spill containment may be required for oil hauling pump-outs by a contract service.

Advantages

  • Energy consumption is low.
  • Diluted solutions are easier to separate.
  • Separation times can be very rapid (30 minutes).

Disadvantages

  • Corrosive chemicals are required for use (sulfuric acid, sodium hydroxide).
  • Chemical treatment is very sensitive to changes in emulsifier (surfactant) chemistry.
  • Specialized instruments are required (pH meter).
  • Instruments require frequent calibration (pH meter).
  • Chemical changes and/or meter malfunctions can result in poor water quality without notice.
  • Balancing chemical reactions, at times, can be more an art than a science.
  • Synthetic fluids cannot be effectively treated by this method.
  • The basic concepts of this method are abstract and are not easily understood by persons without some chemistry background.