Two applications are described where magnesium oxide can be used to purify process water in two ways: to filter out suspended solids and to precipitate dissolved heavy metals. Comparative tests show MgO to be superior to silica sand and garnet sand for the filtration of several different particulates. Head loss occurs at a lower rate with MgO, turbidities are lower, and filter runs can be longer.
MgO could be used in place of sand in existing equipment, and regeneration of the filter can be accomplished by conventional backflushing. Powdered MgO removes heavy metals from water to give a compact sludge that self-cements on standing. It precipitates metals better than lime, and the MgO-hydroxide sludge is more easily filtered or dewatered. The cost of MgO is greater than the cost of lime but the savings in sludge handling may more than compensate for the cost difference.
Water Treatment Magnesium Oxide
WTMag Water Treatment products are non-hazardous, environmentally-friendly, safe and cost-effective treatment options for pH adjustment of potable water. WTMag HP, HP ER, PWT, and PWT MHP are certified by NSF to conform to the requirements of NSF Standard 60 for Drinking Water Chemicals – Health Effects under the categories of pH Adjustment and Coagulation & Flocculation.
The following benefits make WTMag the smart choice for potable water treatment:
| Benefit | WTMag | Caustic Soda | Lime |
| Easy and safe to handle since non-hazardous and non-corrosive | ✔️️ | ❎️ | ❎️ |
| Does not cause scaling problems | ✔️️ | ✔️️ | ❎️ |
| Supplies more CaCO3 alkalinity equivalency / gallon | ✔️️ | ❎️ | ❎️ |
| Long lasting alkalinity / pH control | ✔️️ | ❎️ | ❎️ |
| Non-toxic (when used properly), safe for the environment | ✔️️ | ❎️ | ❎️ |