After passivation, part cleaning or other chemical processes, the passivation acid, the alkaline cleaners, and other chemicals cannot be re-used but also cannot be disposed of until they are neutralized to a suitable pH level.
Requirements vary by chemistry and municipality, but commonly a pH between 6 and 10 is acceptable for disposal into facility drains and sewer assuming there are no hazardous wastes within the used chemistry.
Acid Neutralization Process
Neutralization of a passivation acid such as citric acid or nitric acid typically requires an acid neutralization tank with a base or alkaline solution like soda ash, sodium hydroxide or similar. Determining the amount of base to add to the passivation solution can take a lot of time to determine and mix.
Base / Alkaline Neutralization Process
Neutralization of an alkaline solution like one used for part cleaning typically requires neutralization with an acid such as phosphoric and similar acids. Determining the amount of acid to add to the alkaline solution can take a lot of time to determine and mix.
Automated Chemical Solutions Neutralization Wet Processing Cart
The chemical neutralization tank allows for easy disposal of acids and alkaline solutions by placing the disposable solution to the cart storage tank via the pump on the cart. Once the solution is added, a neutralization solution in a separate container is connected to the cart and a metering pump measures a predetermined amount of neutralization solution, then adds it to the neutralization tank on the cart. The solution is constantly circulated and monitored via pH monitor. The pump continues adding the neutralization solution until the pH is within a preset range.
This automated chemical solution neutralization allows for a no-touch neutralization and allows for an easier disposal into facility wastewater treatment systems and/or a municipality sewer system.
The cart is on wheels/casters for easy transport to application and disposal locations.
Applicable Systems which can Utilize a Chemical Neutralization Tank
Aqueous cleaning parts washers and precision cleaning systems which use a high pH (base/alkaline) solution typically containing sodium hydroxide
Passivation systems which use low pH (acidic) solution to remove free irons part surfaces
Electropolishing systems with acidic based electrolytes