Chemstream has a very unique position when it comes to storm water treatment. Our chemical treatment options work toward the objective of removing suspended solids and dissolved solids from the water. We have a unique water driven dispenser, the Wheel-Treater, which can respond to storm events by applying/metering chemicals without any external power or switches.

Wheel Treater

This is Chemstream’s patented device which automatically treats storm water when the flow occurs. The Wheel-Treater is fabricated out of stainless steel so it is very durable and has an extremely long life. The shaft of the Wheel-Treater's runner operates a peristaltic pump which meters the chemicals into the storm water to be treated.  It automatically shuts off when the water flow stops.

Treating Suspended Solids

We usually recommend a coagulant or flocculant which will agglomerate small suspended particles and make larger ones. These larger “pinfloc” will continue to enlarge until their mass is sufficient enough to start to sink or settle. As these particles settle, a defined layer of higher quality clarified water will form close to the surface and then that water can be decanted back into the environment. With suitable coagulants, clay, silt, and sand particles can easily be removed from water and wastewater.

Treating Dissolved Solids

First, dissolved solids need to be precipitated out of the water.  To do that, usually a pH adjustment upward is recommended. An example is acid mine, or acid rain drainage. That drainage usually has dissolved heavy metals such as iron, manganese, aluminum, copper, zinc and many others. Different metals precipitate out of solution at difference pH levels. For example, iron (Fe) will start to precipitate at a pH of 6.0 and continue to precipitate through a pH of 8.5. Manganese (Mn) has a pH insolubility of 9.6. And aluminum (Al) is insoluble at a pH of 6.6. A challenge arises when there is a combination of metals in the water that precipitate at different pH levels. If some co-precipitation does not occur, it may take a two-stage precipitation process to remove metals to environmentally compliant levels.