Pre-Treatment
Pre-Treatment is a vital part of all water treatment systesm.
The primary objective of pre-treatment is to prepare the water for additional downstream treatment. For some applications, simply adjusting the pH of the water will
effectively change the physical characteristics of the water and perhaps will provide easier downstream treatment. A well designed pit system that removes settleable heavy
solids will reduce the burden the downstream equipment from being overwhelmed. If changing or adding the pit system is not feasible, perhaps adding an above-ground
cone-bottomed clarifier tank is an option. For some applications, where there is an abundance of free-floating oils in the water, pre-treatment to remove excessive
amounts of free-floating oils prior to addressing the emulsified oils may be required.
Maintaining proper pH in the water is crucial to a water treatment system's effectiveness. A balanced pH promotes solids to settle out quicker, emulsified
oils to become more buoyant and some metals to precipitate. Extreme pH levels will negatively impact the performance of a water treatment system.
Automatic adjustment, rather than manually adjusting the pH of the water is highly recommended. Hotsy Clean offers a variety of automatic pH control
systems.
Reinforced, pre-fabricated fiberglass pits are significantly easier and less expensive to ship and install than shipping or constructing on site pits made
of concrete. The fiberglass is chemically resistant and the inner surfaces are impervious, which inhibits the growth of bacteria. When they are properly
installed (e.g., immersed in concrete), they effectively can provide double containment in case of ground movement.
Above-ground cone-bottom tanks can enhance existing pit systems that may be too small, or that do not provide adequate pre-treatment. They can also be
an economical alternative to expensive pit system reconstruction costs. Cone-bottom tanks can also provide lower clean out maintenance, as compared to
some in-ground pit systems.
The first purpose of a wash pad or wash rack is to contain wash water and the constituents in the water. The second purpose is to retain solids
that are heavy enough to settle. The third purpose is to provide adequate dwell/quiet time for overall separation of solids and oils.
