Sulphate in water can be harmful for humans and must be removed from effluents in industrial applications by using Electrocoagulation (EC) treatment systems before its disposal.
What Is Sulfate in Water?
Sulfate, a soluble, divalent anion (SO42−), is produced from the oxidation of elemental sulfur, sulfide minerals, or organic sulfur, and is often found in ground water.
Human made sources of sulfate include the burning of sulfur-containing fossil fuels, household wastes including detergents, and industrial effluents from tanneries, steel mills, sulfate-pulp mills, and textile plants.
High Sulfate Levels in Water Main Problems
The literature in this field clearly demonstrates that high sulfate level in waters may have toxic effects on plants and animal organisms, including, among others, fishes, invertebrates and amphibians, and it may also have negative implications for human health.
Animals are also sensitive to high levels of sulfate. In young animals, high levels may be associated with severe, chronic diarrhea, and in a few instances, death. As with humans, animals tend to become accustomed to sulfate over time. Diluting water high in sulfate with water low in sulfate can help avoid problems of diarrhea and dehydration in young animals and animals not accustomed to drinking high sulfate water. If sulfate in water exceeds 250 mg/L, a bitter or medicinal taste may render the water unpleasant to drink for humans and animals as well.
In industrial applications high sulfate levels may also corrode plumbing, particularly copper piping. Thus, in areas with high sulfate levels, plumbing materials more resistant to corrosion, such as plastic pipe, are commonly used.
Moreover, the water requirements for industrial applications can be very strict, thus a pre-treatment system that removes sulphates may be required.
How to Measure Sulfate Levels in Water and Sewage?
The only way to measure sulfate levels in your water or wastewater is by having the water tested at a laboratory. Once the levels of sulfate in the water are assessed, then a treatment method can be chosen among the most effective ones.
Typically, freshwater SO42- concentrations range from 0 to 630 mg L−1 in rivers, from 0 to 250 mg L−1 in lakes, and from 0 to 230 mg L−1 in groundwater; in seawater SO42- concentrations are typically 2.7 g L−1.
Instead, in industrial applications the sulfate levels can vary widely, thus it’s impossible to estimate those levels without a water content analysis for sulfates. In this case you can book a water analysis at our laboratory by clicking here.
Sulfate Removal System from Water by Electrocoagulation (EC) Technology
Electrocoagulation (EC) is a technology useful for the removal of sulfate and other anions from water and industrial effluents.
The process charges concentrated water through an EC reactor and uses an applied voltage to flow current through the system. By identifying the ideal combination of current density and residence time, it is possible to achieve approximately 40% sulfate removal by EC alone.
On the other hand, carbon filters, water softeners and sediment filters will not remove sulfate from water.
How Does Electrocoagulation Remove Sulfate from Waters?
Electrocoagulation process follows three main stages to remove sulfate from water:
Formation of coagulations by electrolytic oxidation of the sacrificial anode;
Destabilization of the contaminants, particulate suspension, and breaking of emulsions;
Aggregation of the destabilized phases to form flocs.
This treatment method can be either used as pre-treatment for industrial applications that require high purity waters, or as after-treatment system. In fact, Electrocoagulation can be combined with Electro-oxidation processes to improve the treatment results.
These technologies can also be tested thanks to an EC and EO test equipment.
How to Design an Electrocoagulation System for Sulfate Removal from Water?
The first step to design an Electrocoagulation System for sulfate removal is to run a complete laboratory analysis of the water.
Once the analysis is ready, we can choose and configure the best equipment for your application, whether it’s a household drinking water or industrial application. The electrode material needs to be carefully selected to reach the desired results.
PREDEST Electrocoagulation Technologies designed and installed many treatment plants for companies and solved their sulfate treatment problems.