The question of how pricing for Magnesium Hydroxide has come up from discussion with public and private users. Currently, users will see pricing for Magnesium Hydroxide ranging from $ per Gallon, $ per wet pound and $ per dry lb or ton.
Acknowledgements that need to be made about MgOH2 Slurry:
1) Magnesium Hydroxide is a solid substance. Anyone who has ever had a mixer shut off, or cleaned out piping will tell you that MgOH2 (even as slurry) is a solid substance.
2) Magnesium Hydroxide Slurry solutions range from a 10% total solids solution up to 60% Total solids. Total solids is determined by the Manufactures COA and can be verified by taking a sample of slurry and cooking it at 160-200 degrees to drive off the free moisture.
With Magnesium Hydroxide being a solid substances, often contained in a slurry solution it still makes sense that the pricing should be reflective of the solid substance being purchased (Magnesium Hydroxide) and not of the slurry (water). Thus, pricing on a dry weight basis — either dry pound contained or dry ton contained is ideal.
By utilizing pricing based on dry weight — the specification for the slurry become easier to interpret and determine lowest cost.
MgOH2 is priced at $0.25 per pound contained or $500.00 dry ton
1) a truckload of solution weighing 48,400 WET pounds is delivered and the COA states the solution is 54% MgOH2 — thus 26,136 DRY lbs of MgOH2 were delivered
2) a truckload of solution weighing 48,400 WET pounds is delivered and the COA states the solution is 59.5% MgOH2 – thus 28,798 DRY lbs of MgOH2 were delivered
Most deliveries are going to require a certified scale ticket so actual wet weight will be known.
The main problem with pricing on a per gallon basis is the specification for the MgOH2 slurry is not constant — there is a Minimum, maximum and typical % solution that is allowed for.
MgOH2 solution is $2.00/ gallon with a minimum spec of 50% and a maximum of 61%. A typical 50% solution contains 6 dry #/gal whereas a 61% solution can contain 7.5 dry#/gal. That allows for a 20% total solids difference in the slurry to be delivered. A customer would hope that the 61% solution would always be delivered but what incentive does the supplier have to send in more product that they cant bill for. This is the reason that Caustic Soda is priced at a set % solution. Imagine if the spec for Caustic Soda was a liquid that fell between a 25% – 50% solution and the price was the same per gallon — what % solution do you think supplier would deliver?? When was the last time you saw Calcium Hydroxide in slurry form bid on a gallon basis? The only time you see pricing on a gallon basis is when you have a set % solids spec, ie 50% Caustic Soda — not a 48.8% or a 51.2% solution.
Easiest way to hold suppliers accountable for the MgOH2 Slurry and for the customer to pay for what they actually get — request pricing to be on a DRY pound or DRY ton basis contained in a slurry. Have the supplier send a COA and certified Scale ticket with EVERY LOAD.
You can still bid the specification to whatever % solids you want — but, as the consumer, you deserve to only pay for what is delivered.