Safety for your employees has to stay front of mind for wastewater treatment. Phosphorus removal from wastewater can add several chemical feeds that increase the exposure of your employees to hazardous chemicals. This is especially true for traditional iron or aluminum-based coagulants, as their high dosage requirements and low pH decimate alkalinity and usually require pH adjustment like caustic feeds – a serious hazard all by itself.
Better P removal with less hazards with WaterFX
Using lanthanide-based coagulants like WaterFX can significantly reduce the hazards of phosphorus removal from wastewater. The table below compares the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) Safety Data Sheet (SDS) classification and categorization for WaterFX and the most commonly used aluminum and ferric-based coagulants, as well as for caustic, which is usually required when using aluminum or ferric coagulants. Keep in mind that for the GHS categories, a lower number means a more severe hazard.
| WaterFX | Alum | ACH | Ferric | Caustic | |
| Skin irritation | 3 | 1-2 | 1B | 1C to 2 | 1A |
| Serious eye damage | 2B | 1-2A | 1 | 1 | 1 |
| Acute toxicity, oral | 5 | * | 4 | 2.4 | 3-4 |
| Organ toxicity, repeated exposure | 2 | 2 | |||
| Aquatic toxicity, acute | none | 3 | 2 | 2 | 3 |
| pH | 3.0 – 4.0 | 1.4 – 2.6 | <2 | <2 | 14 |
* organ toxicity is not reported but ingestion causes severe burns to mouth and throat.
Alum = Aluminum Sulfate Solution, Al2(SO4)3۰14H2O ACH = Aluminum Chloride Hydrate, AlCl3۰6H2O Ferric = Ferric Chloride Hexahydrate Solution, FeCl3۰6H2O Caustic = Sodium Hydroxide, NaOH
Low dosage enhances the safety of WaterFX.
While the table demonstrates that WaterFX has a much higher pH and is much lower in all hazard categories than traditional coagulants, the low dosage makes it even safer for workers. Most serious accidents involving chemicals happen during transfer of chemicals into storage units or when switching out shipping containers. Due to the unique phosphorus bonding with the lanthanide chemicals in WaterFX, the dosage required to achieve low phosphorus levels may be as much as 10 times less than that required for other coagulants. That means less frequent shipments and chemical transfers, so less frequent exposure of any kind.
WaterFX’s low pH and low dosage requirements eliminate the need for caustic.
Which brings us to the final hazard reduction common for users of WaterFX – elimination of caustic feed for pH adjustment. Keeping in mind that pH is a logarithmic scale, WaterFX is already 10 to 100 times less acidic than traditional coagulants. Combine that with a dosage that may be 10 times less and it is easy to see that WaterFX adds 100 to 1000 times LESS acid to the water. The normal alkalinity in wastewater is usually adequate to accommodate the small dosage of WaterFX needed to meet phosphorus limits. Operators often mention eliminating caustic as among their favorite benefits to switching to WaterFX.
Operators often mention eliminating caustic as among their favorite benefits to switching to WaterFX.
Ready for safer phosphorus removal?
If you are ready to explore improved safety for your operators while also saving money, enhancing treatment performance, and achieving reliable, predictable phosphorus compliance, contact us for a free consultation. We will work with you to see if WaterFX is right for your system.
