Water softeners and dealkalizers are an essential part of many industrial water pretreatment programs. They help reduce and eliminate scale build-up in boilers and other pieces of equipment. Both rely on salt to function properly, but does the type of salt you use really make a difference? The main concerns when working with salt is TSS and hardness. Watertech recently sampled 6 different salts and found that the turbidity and hardness results can vary dramatically. Our best sample was virtually clear with a hardness of 240PPM, whereas the poorest quality sample had very high turbidity and hardness – with a hardness count over 2,000PPM.
The salt you choose can have a significant impact on system performance. Below are results on six samples using 1ml sample saturated brine and 100ml distilled water.
| Salt Sample |
Hardness |
Turbidity |
| Sample 1 |
240 |
Excellent/Clear |
| Sample 2 |
450 |
Good |
| Sample 3 |
650 |
Good |
| Sample 4 |
1,000 |
Good |
| Sample 5 |
2,870 |
Poor |
| Sample 6 |
2,820 |
Poor/Brown |
Sample 1 and 6 after shaking the jars
System Impacts
High Turbidity – Impact on Softeners
If the salt in use contains excessive dirt, this will lead to problems in the brine tank. Layers of dirt will build up on the insides of the tank and require more frequent cleaning and maintenance to keep it running smoothly. A good reference on softener maintenance and brine tank cleaning can be found in our
Knowledge Center.
High Hardness – Impact on Dealkalizers
A chloride cycle dealkalizer uses a type II strong base anion resin which is regenerated with sodium chloride and sodium hydroxide. It exchanges chlorides for alkalinity. The dealkalizer make-up and regeneration water must be hardness free. Even small amounts of hardness (including hardness in the salt) will calcium foul the anion resin. Repeated regenerations with high hardness salt can result in a hardness leakage of >30 ppm in the dealkalizer effluent. Hardness causes problems to equipment downstream in terms of scale and loss of efficiency. Even minimal amounts of scale can lead to dramatic loss in efficiency.
Not all salt is created equal. If you are having issues with high hardness leakage from your softeners and or dealkalizer and question whether the salt in your system might be causing problems, reach out to Watertech at 414-425-3339 or info@watertechusa.com for an evaluation.