Cold Lime Softening

Cold lime softening technology is a well-known and very trusted method for removing hardness and alkalinity caused by minerals such as calcium, magnesium, iron and silica from drinking water.

USALCO® delivers Sodium Aluminate to municipalities and companies for cold lime softening.

How It Works

Cold lime softening is a proven and reliable method that dates back to 1841 when lime was added to the Thames River. Just as today, the minerals were attracted to the lime and created a sludge that settled at the bottom of the river. In this way, the clean water could be easily removed from the top. Modern cold lime softening techniques use the same principles to reliably remove hardness and alkalinity.

Cold lime softening is a form of  precipitation softening that works well at ambient temperatures. It works well for both temporary and permanent hardness. Carbonate or temporary hardness are calcium and magnesium associated with carbonates or bicarbonates in the water. Non-carbonate or permanent hardness are calcium and magnesium in a form combined with chlorides, sulfates and nitrates in the water.

Cold Lime Softening Solutions

At USALCO, lime, sodium hydroxide and sodium aluminate are usually recommended to cold lime soften in varying degrees and or combinations.

The characteristics of the influent water to be treated, such as the levels of calcium, magnesium, iron and silica in the raw water, (as well as the desired finished water quality) are the primary factors that determine use and application of the right chemicals.

LSA 38 (Liquid Sodium Aluminate)

USALCO’s LSA 38 (liquid sodium aluminate) has been proven to be extremely effective where additional and or improved magnesium removal is required. USALCO LSA 38 also works to provide the following treatment benefits:

  • Increases silica removal
  • Provides the needed hydroxyl ion (OH-)  for magnesium reduction without increasing calcium hardness in treated water
  • Hydrolysis of sodium aluminate to aluminum hydroxide aids in floc formation

As in the historical example, the cold lime softening treatment converts the soluble contaminants (i.e., hardness, alkalinity) to insoluble compounds that sink to the bottom of your settling basin or clarifier. The clean water can be pulled from the top and the compounds remain at the bottom. These compounds can then be easily removed by settling and mechanical separation.

Free Jar Testing & Trials

USALCO offers free jar testing and trials to optimize chemical dosages.

Packaging & Delivery

We supply our cold lime softening products in bulk quantities using dedicated transportation equipment to ensure quality. We also offer multiple plant locations for additional economy and convenience.

How Can We Support Your Cold Lime Softening Requirements?

USALCO offers consistent performance and value, as well as economy. If you would like more information, a quote or further insights on cold lime softening, please contact us.