Liquids are a Tool. What We Will Cover 4/26/2010. Performance issues for Liquids. Environment issues for Liquids. Economics issues for Liquids

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1 Liquids are a Tool Liquids are not a replacement for solid de-icers The Science behind anti-icing, icing de-icing and pre-wetting. Ken Ossian Ossian Inc. Use Liquid and Dry in Combination Liquids melt from bottom up Solids melt from top down What We Will Cover Performance issues for Liquids Environment issues for Liquids id Economics issues for Liquids Calculating Melt Values Eutectic Temperature Lowest freeze point of a de-icer in water. SHRP Testing Test standards development by the Strategic Highway Research Program for determining melt value 1

2 Defining Eutectic The Confusion of Eutectic Eutectic is not the melting value Eutectic describes a solution s lowest freezing point. This minimum freezing point of a deicer in water is often called the eutectic temperature or simply eutectic Example: Freeze Point for varying solutions of salt. Data courtesy of the Salt Institute SHRP Melting Tests SHRP Testing Methodology Strategic Highway Research Program Liquid Test SHRP H SHRP standardizes a scientific methodology for measuring melt value. Much more accurate for judging relative performance than eutectic points. 2

3 SHRP Testing Methodology SHRP Testing Methodology SHRP Testing Methodology Benefits of SHRP Best for measuring actual melt value Allows isolation of variables Measuring melt value rather than freeze point Standardization of test allows accurate comparisons 3

4 SHRP Melt Value v. Eutectic Melt Value Summary When evaluating ice melter value, make decisions based on actual melt value determined by SHRP testing. Chemical Performance Issues Potassium Acetate Sodium Acetate Calcium Chloride Magnesium Chloride Bio-Based Products Salt Potassium Acetate Upside Bio-degradable Non-chloride Exceptional melt value Designed for specific use areas Airport Runways Bridges Parking Decks Downside Very expensive 4

5 Sodium Acetate Dry Product can be dissolved and used as a liquid Upside Bio-degradable Non chloride Melt value little less than salt Designed for specific use areas Downside Expensive Calcium Chloride Upside Starts out as a liquid Significant melt value Low temperature melting Pre-wetting salt for lower temp melting Available as a dry and liquid Small amounts work well in salt blends Downside More expensive than salt brine Hygroscopic / Temperature Sensitive - When applied at warmer temperatures Magnesium Chloride Upside Starts out as a liquid Significant melt value Low temperature melting Pre-wetting salt for lower temp melting Available as a dry and liquid Small amounts work well in salt blends Downside More expensive than salt brine Hygroscopic / Temperature sensitive - When applied at warmer temperatures Could have concrete issues in certain regions of the country Bio-based Products By-products of Agricultural Industry Sugar / Protein Primarily used as an additive Upside Makes other products better Reduce Corrosion Increases melt value of salt Increases residual effect of liquid anti-icers Downside Adds cost 5

6 Salt Cheap and it works Not so cheap anymore Salt Upside Still the lowest cost de-icer Downside Over applied Environmental impact Vegetation Corosion Water run off Challenge is not to eliminate but to reduce salt use Liquid Comparisons Based on SHRP melt values Performance Summary Evaluate based on melt value not eutectic There are pluses and minuses for every de-icer Look at what works for you. 6

7 Environment: Means more than vegetation Environment Issues Often out-weigh economic and performance issues Know your environment. Physical concerns Human concerns Weather concerns Ecological concerns Vegetation Water run off Environment: Means more than vegetation Identify Physical Environment Vital Services Facility Parking Ramp Parking lot (runoff issues) Helicopter Pad Emergency Entrance Sidewalks Sidewalks w/ vegetation Roads in and out Runoff Lake Environment: Means more than vegetation Identify Human Environment Who is doing the application and how much training, if any, have they had? How much supervision is available? How does this apply to chemistry issues? Environment: Means more than vegetation Identify Weather Environment Time of day of application Timing of traffic patterns people, autos Temperature Ground Temp, Not Air Temp. Direction of temperature - Forecast Going down Going up Surface Freezing rain Ice Packed snow Did we anti-ice? 7

8 Environment: Means more than vegetation Identify Ecological Environment Environment: Vegetation Issues Main advantage of liquids is less material used Vegetation Friendly Vegetation Positive Run off water contamination Wildlife risk Environment: Environment: 8

9 Environment: Means more than vegetation Summary of Environmental Issues Know your environment Know your product One product does not solve all environmental problems Economics The Liquid Advantage Pre-wetting Anti-icingicing De-icing Know how many variables you re dealing with. Pre-wetting Salt Pre-wetting Options Objectives make salt melt more effectively which results in using less salt which saves money The value of pre-wetting salt is well known A long and established practice Almost Anything Works (results may vary) 9

10 Pre-wetting Options (most common) Salt brine Magnesium Chloride Calcium Chloride Bio-based/Organic (source of sugar/protein) Sugar beet Corn sugar Cane sugar Bio-based additives reduce corrosion All pre-wet products reduce bounce and scatter How much to use Recommendations range from 2gal/ton to 12gal/ton Some recent advocates recommend higher rates with ih the goal of creating a slurry Pre-wetting Economic Pay back Performance gain average of 25% Can now use 3 tons of salt where previously used 4 tons If salt costs $70/ton, savings per ton could be $23.33 What is my liquid cost per ton? 10

11 Is More Better? Is More Better? How much to use Popular opinion on pre-wetting The more the better Currently no test method beyond 4gal per ton Main advantage of heavy pre-wetting is reducing bounce and scatter. Important when spreading on roads Less important when spreading on parking lots Best data is field data Keep records and monitor performance Graph and Data Courtesy McHenry County, IL 11

12 Pre-wetting Summary Pre-wetting Summary It works Economic payback Images Courtesy of the City of Comanche Images Courtesy Eco Solutions Anti-icing Application of liquids before the storm Salt brine Calcium Chloride Magnesium Chloride Bio-based Or blends of the above Anti-icing Application rates 1gallon per 1000sqft gal per acre approximate gal per lane mile (range) Anti-Icing in Grey County Courtesy Eco Solutions Image Courtesy Winter Services 12

13 Anti-icing Anti-icing Comparison of Untreated and Treated Areas of parking lot. Bio-based liquid was applied as a liquid anti-icer several hours prior to winter event on one half of parking lot - shown on right side of photo. After overnight snow a standard shovel was used to remove accumulation. The area pre-treated easily shoveled to a clean surface without additional labor or material. The untreated area left a thin layer of snow bonded to the surface that would require additional material or labor to remove. Comparison of Untreated and Treated Areas of parking lot after an 8 hour day without additional material or labor applied. Daytime weather consisted of additional light snow fall with wind. The residual effect of the bio-based liquid anti-icer application exceeded expectations by continuing to maintain a relatively clean surface. The untreated area with bonded snow, filled in over the course of the day with additional accumulation and blowing snow. Comparison of Untreated and Treated sides of a parking lot. Right side of parking lot was treated with a bio-based liquid anti-icer during regular business hours before a winter storm event late that evening. The visual comparison shown is the natural performance of anti-icer without any physical snow removal. A sunny day following the storm aided in the liquid s performance. Anti-icing Anti-Icing Performance Temps (Ground Temperature) Salt brine or salt brine/bio-base combination 15º F and up Comparison of Treated and Untreated areas of a sidewalk entrance paved with a decorative aggregate material. A bio-based liquid anti-icer was applied the day before the winter storm event on the sidewalk and the left side of the walkway leading to the building entrance. Prior to removal of snow by shovel, morning foot traffic stamped foot prints in the snow on both the treated and untreated areas. After photo was taken, accumulated snow was removed by shovel. Comparison of Treated and Untreated Areas of sidewalk entrance after 2 hours without additional de-icer material applied. The areas treated with an anti-icer have been clean and safe for foot traffic since the removal of snow. The untreated area still exhibits frozen foot tracks that can cause a slip and fall accident as well as snow that is still trapped in the cracks of the aggregate material maintaining a slick surface. Calcium Chloride / Magnesium Chloride Lower temperature performance Do Not Apply above 32º F 13

14 Anti-icing Summary DOTs, counties, municipalities For every 1lb of liquid used for anti-icing, saves 4 lbs of solid de-icer. Every gallon of liquid saves 9 lbs of salt De-icing with Liquids If you anti-iced prior to storm Light snow may not even need a follow up Plow / Apply / Repeat Sidewalks Liquids create slush Slush will refreeze creating hazard Remove slush Your Liquid Economic Advantage Salt Brine Do you make your own brine? Close to someone who does make it? Are you adding a bio-based based product or buying a finished blend from someone who does? Calcium Chloride Do you have an economic advantage? Magnesium Chloride Do you have an economic advantage? Economics Summary Liquids reduce salt consumption Pre-wetting Enhance performance Reduce bounce & scatter Anti-icing 1 gallon used as pre-treat saves 9lbs in post treat De-icing Reduce salt use where possible 14

15 SIMA 2009: Advanced Liquids Advanced Liquids Summary Performance Compare products with SHRP melt values, not Eutectic Points Environment Know your environment Physical, Human, Weather, Ecological One product does not solve all problems The best cost option may not be the lowest cost product Economics of liquids Pre-wetting, Anti-icing and de-icing with liquids will reduce costs Thank You Ken Ossian Ossian Inc. 15