Scale (hard mineral coatings) and corrosion deposits are made up of solids and sediments that collect on or in the distribution system piping, storage reservoirs and household plumbing. Corrosion product solids can be:
- Lead carbonates and oxides.
They form directly from the corroding metal pipe wall. The sediments consist of corrosion by-products and precipitated solids such as:
- Manganese oxides;
- Aluminum hydroxide;
- Calcium carbonate;
- Solids that carry over from water treatment plants.
The scale and corrosion deposits serve as sites for adsorption or coprecipitation, as well as for mineral growth for certain contaminants, such as:
Scale typically occurs when minerals in produced water surpass saturation limits as pressures and temperatures change. Both scale buildup and corrosion can take a variety of forms, but when found in and on pipes, wells, tubing and equipment, the results are largely the same; reductions in flow rates, production and efficiency losses, and often damaged equipment and replacement costs. Across industries, effective water and wastewater treatment programs must take scale-inhibition and corrosion control into account to safeguard productivity, protect assets, and mitigate risks.