EnviroTech Services Inc.
All too often when bidding on liquid deicers we see product specifications that are incomplete. When a product specification is incomplete, the requesting agency will only get the bare minimum of what they are specifying in the bid. In addition, the requesting agency may be getting a number of other things that they do not want!
Let's take a look at this actual bid specification: "4500 gallons of liquid magnesium chloride." Yes, that is the entire bid specification for their liquid material. Take this in contrast to the 40 pages-plus document for liquid deicers the Pacific Northwest Coalition (British Columbia, Idaho, Montana, Oregon, Washington) use at http://www.wsdot.wa.gov/fossc/maint/pns/deicespec/99DeicerSpecs.htm.
Ultimately, you need to set your specification for your needs. Keep in mind once again that if you do not specify some characteristic in your deicer, you will most likely not get it. Below we have attempted to address several of the major areas where we typically see shortcoming in specifications.
1) Minimum 30 percent magnesium chloride solution
2) Minimum magnesium chloride solution 30 percent solids
These two specifications are not equal. What you are interested in is the amount of active ingredient in solution. Unless you are buying a reagent grade or pharmaceutical grade of deicer (and therefore drastically overpaying), there will be other minerals or materials in solution. While these other materials in your deicer solution may not be harmful, they are not what you are after or should be paying for.
Number 1 above correctly states what the purchasing agency is after, a magnesium chloride solution where 30 percent of the volume by weight is magnesium chloride, the remaining material by weight will be water plus other materials or minerals in solution. If there are other materials in solution they do not count towards the minimum concentration of magnesium chloride.
Number 2 above, while it appears like number 1, is actually VERY different. Do not allow a vendor to talk you into writing a specification like this. Magnesium chloride is the melting agent you desire and are paying for. The other materials in solution can be considered filler-even if they have some melting capability such as potassium or sodium chloride, they are much lesser-performing deicers and ultimately take away from the melting capacity if replacing magnesium chloride. A material that is 25 percent magnesium chloride, 2 percent sodium chloride, 2.5 percent sulfate, and 1 percent potassium chloride will pass the specification number 2, but not specification number 1. If you stack up this material versus a 30 percent magnesium chloride material, the 25 percent magnesium chloride will melt considerably less snow/ice at all temperatures than the 30 percent magnesium chloride material.
Make sure when specifying your inhibitor that you set a level of protection that you desire such as less corrosive than tap water or 70 percent less corrosive than salt. If you do not set the level, you are looking for almost anything that can be considered a corrosion inhibitor and at any amount. For instance, milk is less corrosive than calcium chloride. If an agency simply specifies that a corrosion inhibitor must be added to their calcium chloride, a vendor could take one gallon of milk per 4500 gallons of calcium chloride and has legally met the requirements. However, this did not accomplish anything and has probably made it whereby another vendor that spent the money to inhibit his calcium chloride has lost the bid.
The second thing to make sure is that the corrosion inhibitor has been preapproved in some fashion. One agency learned the hard way when the vendor they were using called up a chemical company and requested an inhibitor. The inhibitor turned out to be oil based and everywhere their liquid truck went the accidents followed-all at slightly above freezing, too.
The above items are what all liquid deicer specifications should include. Your situation will dictate the levels at which the parameters should be set. There is also no need to recreate the wheel in writing specifications. Contact us and we can refer you to agencies which have solid specification (some of which learned the hard way).
With quality specifications everyone wins-well, except maybe the unscrupulous vendor. Once you know the specifications you want in place, the next step is to develop the testing methods which you will utilize.
Kirk Kaiser can be reached at 913-894-1643 or at Kaiser@envirotechservices.com.