IER Brings Magnesium Hydroxide to the Pacific Northwest:
For centuries Milk of Magnesia, the common name for Magnesium Hydroxide, Mg(OH)2, has been the medicinal ingredient of choice as an antacid and laxative for human digestive systems.

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More recently, ant-acids like Rolaids, which contain up to 20% Mg(OH)2, have been used. Now, this same safe and gentle alkaline additive is being provided economically for acid neutralization of municipal and industrial wastewater from strategically located distribution plants in Pasco, WA and Paul, ID by Inland Environmental Resources (IER) and can be delivered in quantities from full truckloads to totes.

Benefits of “Mag” for Acidic Wastewater: If not properly neutralized, acidic wastewater can cause accelerated corrosion damage to land application (crop circle) equipment, and the low pH/alkalinity allows for the release of malodorous hydrogen sulfide and volatile organic acids. Acid neutralization with sodium hydroxide (caustic) or soda ash (sodium carbonate) often results in an unacceptable increase in effluent TDS for land applications. Alternatives such as potassium hydroxide (very expensive) and lime (hazardous/difficult to handle) have their own limitations.


Benefits of “Mag” for Secondary Treatment: Another undesirable attribute of acidic wastewater is that it minimizes the efficiency of secondary treatment processes to biologically remove dissolved solids (BOD). Through the use of Magnesium Hydroxide the optimal pH range for aerobic and anaerobic microorganism performance can be easily maintained, with no pH spiking. Because of its gentle buffering nature, it is virtually impossible to overfeed Mg(OH)2 above a pH of 9. pH spikes from use of caustic, soda ash, or lime can shock the aerobic and anaerobic populations into periods of very poor BOD removal. Unlike caustic or soda ash, which add sodium, Magnesium Hydroxide adds nutrient value (magnesium) into secondary treatment biological processes and returns nutrient to irrigated soils.


Alkalinity and Coagulation from the Same Additive: Another unique difference between Mg(OH)2 and caustic or soda ash is the coagulation benefit that the Mg2+ ion provides for improved TSS removal and sludge settling. Like ferric chloride or aluminum sulfate (alum), the magnesium cation aids in the coagulation of suspended solids, which commonly results in decreased sludge volume and a decrease in the usage rate of expensive organic coagulants and polymers. Unlike ferric chloride or aluminum sulfate, which are strongly acidic in nature, Magnesium Hydroxide simultaneously increases the pH/alkalinity and provides coagulation benefits. In addition, because of the increased charge density of Mg2+ compared to Ca2+, Mg(OH)2-treated wastewater provides a much more compact sludge than is observed using the other pH neutralizer chemistries, resulting in significantly reduced sludge volume.


Magnesium Hydroxide is Extraordinarily Safe to Handle: IER’s distribution plants supply a 58-62% slurried product having a neat pH of 10.5. This pH is very safe to handle and is not dangerous to skin. As a slurry, the product requires on-site storage in a vessel fitted with a mixer to provide an evenly distributed product within the vessel. IER can provide the storage, agitation, and pumping capabilities for any application, big or small.


Not All Magnesium Hydroxide Products Are Equal, particularly with respect to purity, slurry settling rate, and ease of metering the product. Below is a comparison of the purity of Inland Environmental Resources’ Mg(OH)2 product versus a competitive product:
Product Purity Total Solids Mg(OH)2 Solids .
Competitor’s Product 93% MgO 61-65% solids 56.7-60.4% Mg(OH)2
IER’s Product >97.2% MgO 58-62% solids >56.2-60.1% Mg(OH)2


The IER Mg(OH)2 product has a guaranteed minimum purity of 97.2% as MgO. In addition, the IER Mg(OH)2 slurry contains a food-grade dispersant which greatly minimizes product viscosity, markedly enhances the ease of pumping, and decreases the setting rate of the suspended slurry. Other Mg(OH)2 products may have acceptable pumpability, but do not possess the same ability to remain suspended or to be readily re-suspended after periods of stagnation.