Salt Brine Blending to Optimize Deicing and Anti-icing Performance and Cost

Effectiveness

Stephen J. Druschel, PhD, PE Sarah Green

Alex Raymond

Deicing and Anti-icing – Balancing Performance & Cost

What is the melt capacity of a selected chemical treatment?

What is the cost of a selected chemical treatment?

Evaluating Deicers SHRP H-205 Analyses

• Ice Melting • Ice Penetration • Ice Undercutting • Corrosive Effects • Scaling Effects • Frictional Characteristics • Ecological Effects

Evaluating Deicers SHRP H-205 Analyses

• Ice Melting •Ice Penetration •Ice Undercutting •Corrosive Effects •Scaling Effects •Frictional Characteristics •Ecological Effects

Focus on Ice Melting

• Factor with greatest impact when already deicing • Penetration and undercutting related

Evaluating Deicers SHRP H-205 Analyses

SHRP H-205.1 • 9” diameter sample, 1/8” thick, 130 mL • Walk in cooler • Glove box to prevent warm drafts • Three cycles of brine reapplication

MSU Mankato • 2” diameter sample, ¼” thick, 50 mL • Digital freezer or brine solution in cooler • ¾” aluminum plate for temperature stability • Three cycles of brine reapplication

Why the Difference in Method?

Deicing and Anti-icing Treatments

• Sodium Chloride (NaCl) • Cargill, NA Salt

• Magnesium Chloride (MgCl2) w/additives • Envirotech Serv., Scotwood Ind., NA Salt

• Calcium Chloride (CaCl2) • Tiger Calcium

• Potassium Acetate • Scotwood Ind., Cryotech, NAAC

• Beet juice/molasses/other carbohydrates • NA Salt, Envirotech Serv., SNI Sol’ns, Pollard Hwy Prod.

Rock Salt is So Yesterday…Isn’t It???

MSU Mankato Ice Melt Capacity Evaluation

MSU Mankato Ice Melt Capacity Evaluation

MSU Mankato Ice Melt Capacity Evaluation

MSU Mankato Ice Melt Capacity Evaluation

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-10 -5 0 5 10 15 20 25 30

Ice

Mel

t Cap

acity

(mL

brin

e cr

eate

d / m

L or

g o

f de

icer

app

lied)

Temperature (degrees F)

Ice Melt Capacity by Temperature

Salt Brine 23.3%

Blanche Rock Salt

Solid Deicers In Comparison to Rock Salt

Material Base @ 12 F @20 F @ 28 F Clearlane Enhanced MgCl2 130% 95% 70%

SOS @ 6 gal/ton MgCl2 135% 90% 115%

Thawrox Gold Treated MgCl2 150% 120% 115%

Ice Slicer CaCl2 130% 95% 70% Ice Bite @ 3 gal/ton Carb 135% 110% 105%

Liquid Deicers In Comparison to Salt Brine

Material Base @ 12 F @20 F @ 28 F

AP Liquid Deicer MgCl2 160% 185% 135%

Articlear Gold MgCl2 170% 80% 100%

Freezeguard MgCl2 205% 190% 160%

Ice Ban 200M MgCl2 200% 160% 105%

Meltdown Apex MgCl2 175% 160% 135%

SOS MgCl2 175% 170% DNT

TC Econo MgCl2 130% 180% 80%

Thawrox Gold Alt MgCl2 160% 140% 115%

Liquid Deicers In Comparison to Salt Brine Material Base @ 12 F @20 F @ 28 F

Calcium Chloride CaCl2 160% 185% 135%

RGP-8 CaCl2 170% 80% 100% Geomelt 55 Carb 115% 110% 60% Geomelt Gen 3 Carb 100% 100% 65% LCS 5000 Carb 70% 60% 65% Ice Bite Carb 315% 200% 220% Alpine Ice Melt Acetate 170% 160% 130% CF-7 Acetate 200% 110% 105% Apogee NonChloride Acetate 175% 175% 120%

Brine Blend Evaluation

Materials • MgCls

• Articlear Gold • SOS

• CaCls • Calcium Chloride • RGP-8

• Carbohydrates • Geomelt Gen 3 • LCS 5000

Mixtures • NaCl Brine (23.3%) as base • Additives at 10%, 20% & 30% • Triplicate specimens/mixture • Multiple temperature levels

• Nine specimens/temperature

y = -0.8333x + 3 R² = 0.08333

y = 6.3694x + 1.7694 R² = 0.88854

y = 0.8333x + 2.1667 R² = 0.08333

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10

0% 10% 20% 30% 40%

Ice

Mel

t Cap

acity

(mL

brin

e cr

eate

d / m

L d

eice

r brin

e bl

end)

Deicer Additive Blend Rate

Ice Melt Capacity by Brine Blend Rate Articlear Gold Additive

23 deg F 19 deg F 18 deg F

Stockpile Treatment Evaluation Materials • Calcium Chloride • Magnesium Chlorides

• AP Liquid Deicer • APEX • Articlear Gold • Clearlane • Freezeguard • SOS • Thawrox Gold

• Carbohydrate: Geomelt 55

Mixtures • Rock Salt as base • Additives at 3, 6, 12 & 30 gal/ton • Triplicate specimens/mixture • Multiple temperature levels

• Twelve specimens/temperature

• Acetates • Alpine Ice Melt, Apogee Non Chloride, CF-7

y = -0.0169x + 8.7683 R² = 0.17627

y = 0.0129x + 5.0623 R² = 0.23726

y = 0.002x + 2.0146 R² = 0.00324

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0 5 10 15 20 25 30 35 40 45 50

Ice

Mel

t Cap

acity

(mL

brin

e cr

eate

d / g

dei

cers

)

Deicer Additive Rate (gal/ton)

Ice Melt Capacity by Stockpile Treatment Rate Calcium Chloride

23 deg F

18 deg F

0 deg F

- 30° Ice Melt Capacity Evaluation Materials • Treated Rock Salts • Liquids That Didn’t Freeze

Material Form IMC Avg (ml/g)

Rock Salt Solid 0.0 Ice Bite Solid 0.0 Clearlane Trtd Solid 0.0 Thawrox Trtd Solid 0.0 Ice Slicer Solid 0.0 SOS Trtd Solid 0.0 Alpine Liquid 2.0 CF-7 Liquid 1.8 RGP-8 Liquid 1.8 Meltdown AP Liquid 1.8 Freezeguard Liquid 1.7 Apex Liquid 1.5 Ice Ban Liquid 1.3 Thawrox Gold Liquid 1.3 Geomelt Gen3 Liquid 1.3 Articlear Gold Liquid 1.0 SOS Liquid 0.9 TC Econo Liquid 0.8

Cost Models – Deicing & Anti Icing • Compare to Expected Performance

• Rock Salt or Salt Brine at 28° F

• Adjust by Ice Melt Capacity

• Use Deicer Prices as Delivered

• Determine Cost to Reach Expected Performance

• Graph of cost per lane mile at a given temperature

$0

$20

$40

$60

$80

$100

$120

$140

-35 -25 -15 -5 5 15 25 35

Cos

t/Lan

e M

ile

Temperature °F

Cost/Lane Mile of Granular Deicers

Rock Salt

Clearlane Enhanced

SOS @ 6 gal/ton

Thawrox Gold Treated

Ice Slicer

Ice Bite @ 3 gal/ton

$0

$20

$40

$60

$80

$100

$120

$140

$160

$180

$200

-35 -25 -15 -5 5 15 25 35

Cos

t/Lan

e M

ile

Temperature °F

Cost/Lane Mile of Liquid Anti Icing

Salt Brine

Articlear Gold

Freezeguard

TC Econo

Thawrox Gold Alternative

RGP-8

Geomelt Gen 3

CF-7

Conclusions •  Ice Melt Capacity – ice melted/deicer applied

•  Temperature •  Number of chloride (or similar) ions on ice

•  Brines – typically 75% water, so lower IMC

•  Stockpile treatments & brine blends •  Limited improvement in IMC – stockpile treatments •  Modest improvement in IMC – brine blends •  Other benefits (e.g., color, stickiness) may matter

•  Cost effectiveness is strongly influenced by: •  Temperature-dependent ice melt capacity •  Deicer performance standard: 28° F rock salt or salt brine •  Deicer pricing as delivered

Acknowledgements

•  Minnesota Department of Transportation •  Research Contract 96319

•  Minnesota State University •  Center for Transportation Research and

Implementation