Formulations for Aircraft and Airfield Deicing and Anti-Icing: Aquatic Toxicity and Biochemical Oxygen Demand (2009) / Chapter Skim
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From page 4... ...
2-1 SECTION 2 LITERATURE AND DATA REVIEW The first step in this project was establishing a central repository of references regarding toxicity of ADF components, sources of BOD, environmentally friendly alternatives for ADF components, performance issues, and operational issues. This section summarizes the information in this repository.
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From page 5... ...
2-2 TABLE 2-1 Summary of SAE Environmental Testing Standards for Deicers Runway and Taxiway Deicing/Anti-Icing Compounds Environmental Parameter Aircraft Fluids (AMS 1424 and 1428) AMS 1431 AMS 1435 BOD 20°C for 5, 15, and 20 or 25 days 20°C for 5, 15, and 20 days None COD or TOD Results expressed as kg O2/kg Results expressed as kg O2/kg 5-day theoretical TOD expressed as kg O2/kg Biodegradability Results expressed as BODx/TOD or COD for all time intervals Percent biodegradation for 5-, 15-, and 20-day incubation periods.
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From page 6... ...
2-3 TABLE 2-2 Freezing Point Depressants Chemical CAS # Reference 1,2-Propylene glycol 57-55-6 Ashwari and Coffey, 1993; Bloom, 1986; Boluk et al., 1999; Hu et al., 1998; König-Lumer et al., 1982; Nieh, 1992 1,3-Butanediol 107-88-0 Lockyerm et al., 1998; Westmark et al., 2001 1,3-Propylene glycol 504-63-2 König-Lumer et al., 1982; Lockyerm et al., 1998 Calcium acetate 62-54-4 Hoenke and Rynbrandt, 1992 Diethylene glycol 111-46-6 Ashwari and Coffey, 1993; Boluk et al., 1999; König-Lumer et al., 1982; Ma and Comeau, 1990; Nieh, 1992 Dipropylene glycol 25265-71-8 Ashwari and Coffey, 1993; Boluk et al., 1999; Nieh, 1992 Dulcitol 608-66-2 Back et al., 1999 Erythritol 149-32-6 Back et al., 1999; Simmons et al., 2007 Ethyl lactate 97-64-3 Sapienza et al., 2003 Ethylene glycol 107-21-1 Ashwari and Coffey, 1993; Bloom, 1986; Boluk et al., 1999; Hu et al., 1998; König-Lumer et al., 1982; Ma and Comeau, 1990 Glycerol 56-81-5 Back et al., 1999; Boluk et al., 1999; Simmons et al., 2007; Westmark et al., 2001 Magnesium acetate 16674-78-5 Hoenke and Rynbrandt, 1992 Mannitol 69-65-8 Back et al., 1999; Sapienza et al., 2003 Pentaerythritol 115-77-5 Back et al., 1999 Polyethylene glycol, mw from 62 to 106 25322-68-3 Boluk et al., 1999 Potassium acetate 127-08-2 Comfort, 2000; Sapienza et al., 2003 Potassium formate 590-29-4 EPA Office of Water, 2000 Proline 147-85-3 Sapienza et al., 2003 Sodium acetate 127-09-3 Comfort, 2000 Sodium formate 141-53-7 Comfort, 2000; Hoenke and Rynbrandt, 1992 Sodium lactate 72-17-3 Sapienza, 2003 Sodium pyrrolidone carboxylate 54571-67-4 Sapienza, 2003 Sorbitol 50-70-4 Back et al., 1999;Sapienza, 2003; Sapienza et al., 2003; Simmons et al., 2007 Triethylene glycol 112-27-6 Boluk et al., 1999; Westmark et al., 2001 Urea 57-13-6 Comfort, 2000 Xylitol 87-99-0 Simmons et al., 2007
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From page 7... ...
2-4 Surfactants Surfactants reduce the surface tension of the applied deicer fluids to ensure they completely coat aircraft and runway surfaces. Surfactants may also reduce the adhesion of ice to surfaces making removal easier.
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2-5 Corrosion Inhibitors ASM specifications for deicers include standards for effects on materials typically found in aircraft and on runways. These materials include aluminum alloys, high-strength steels, titanium alloys, polycarbonate plastics, copper wiring, carboncarbon composites, asphalt, and concrete.
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From page 9... ...
2-6 TABLE 2-5 Thickening Agents Chemical CASN Reference Carbopol 1610, polyacrylic acid -- Ashwari and Coffey, 1993; Nieh, 1992 Carbopol 1621, polyacrylic acid -- Ashwari and Coffey, 1993; Nieh, 1992 Carbopol 1622, polyacrylic acid -- Ashwari and Coffey, 1993; Nieh, 1992 Carbopol 672, polyacrylic acid -- Ashwari and Coffey, 1993; Nieh, 1992 Carbopol 934, polyacrylic acid -- Ashwari and Coffey, 1993; Nieh, 1992 Carboxymethylcellulose -- Ma and Comeau, 1990 Cross-linked polyacrylic acid -- König-Lumer et al., 1982; Nieh, 1992 Hydroxyethylcellulose 9004-62-0 Ma and Comeau, 1990 Iota-carrageenan 9062-07-1 Tye et al., 1987 Kappa-carrageenan -- Tye et al., 1987 Polyvinylpyrrolidone mw = 10,000–700,000 -- Simmons et al., 2007 Welan gum -- Westmark et al., 2001 Xanthan gum -- Lockyerm et al., 1998; Ma and Comeau, 1990; Westmark et al., 2001 Defoamers The surfactants added to ensure adequate surface wetting may also increase the tendency of a fluid to foam. Defoamers decrease the stability of foam, often by increasing foam drainage or decreasing film thickness.
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From page 10... ...
2-7 pH Modifiers It is typically desirable to have deicers' pH range from 7 to 9. This range can be obtained by using basic chemicals such as sodium hydroxide, potassium hydroxide, or ethanol amines.
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2-8 TABLE 2-9 Oils Used as Hydrophobic Agents Chemical CASN Reference 1-Dodecanol 112-53-8 Lockyerm et al., 1998 Dimethyl polysiloxane (10 to 20 cSt) -- Ma and Comeau, 1990 Mineral oil (avgC = 15; P = 65%, N = 35%)
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From page 12... ...
2-9 TABLE 2-11 Toxicity Values of Commercial Components as Reported in the ECOTOX Database Chemical Function Species Toxicity Dipropylene glycol FPD Goldfish LC50 24hr >5,000 mg/L Disodium phosphate pH Modifier Daphnia magna LC50 48hr 3,580 mg/L Ethyl lactate FPD Zebra danio LC50 96hr 320 mg/L Ethylene glycol FPD Rainbow trout LC50 96hr >18,500 mg/L Glycerol FPD Rainbow trout LC50 96hr 54 mgl/L Monoethanolamine pH Modifier Rainbow Trout LC50 96hr 150 mg/L Pentaerythritol FPD Daphnia magna EC50 24hr 38,900 mg/L Polyacrylic acid Thickener Bluegill LC50 96hr 1,290 mg/L Polyethylene glycol, mw from 62 to 106 FPD Rainbow trout LC50 96hr >20,000 mg/L Potassium hydroxide pH Modifier Guppy LC50 24hr 165 mg/L Potassium phosphate Corrosion inhibitor Western mosquitofish LC50 96hr 750 mg/L Propargyl alcohol Corrosion inhibitor Fathead minnow LC50 96hr 1.53 mg/L Sodium acetate FPD Fathead minnow LC50 120hr 13,330 mg/L Sodium azide Antimicrobial Rainbow trout LC50 96hr 2.75 mg/L Sodium formate FPD Bluegill LC50 24hr 5,000 mg/L Sodium hydrogenphosphate pH Modifier Daphnia magna LC50 48hr 3,580 mg/L Sodium hydroxide pH Modifier Western mosquitofish LC50 96hr 125 mg/L Sodium nitrate Corrosion inhibitor Rainbow trout LC50 96hr 1658 mg/L Thiourea Corrosion inhibitor Daphnia magna LC50 48hr 9 mg/L Triethanolamine pH Modifier Fathead minnow LC50 96hr 11,800 mg/L Triethylene glycol FPD Fathead minnow LC50 96hr 77,400 mg/L Urea FPD Guppy LC50 96hr 17,500 mg/L Xanthan gum Thickener Rainbow trout LC50 96hr 420 mg/L Toxicity data are invariably sparse and inconsistent for these components. However, the available literature values are helpful in identifying components with high and low toxicity values and raise some general questions about how toxicity should be considered when selecting components for new deicers.
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From page 13... ...
2-10 As an example of the complexities of interpreting product characteristics, the technical literature for Carbopol polymers (Noveon, 2001) , a polyacrylic acid product, states that this toxicity is believed to be caused by "exhaustion" -- the polymer thickens the surrounding water to such a degree that swimming becomes difficult or impossible.
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From page 14... ...
2-11 TABLE 2-12 Summary of Available Information Regarding the Environmental Characteristics of Aircraft Deicing and Anti-icing Fluids BOD5 BOD20 (mg/L) Aquatic Ecotoxicity Acute Toxicity to Fish Acute Toxicity to Aquatic Inverts Toxicity to Aquatic Plants Brand Name FPD Manufacturer/ Distributor Product No.
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2-12 TABLE 2-12 Summary of Available Information Regarding the Environmental Characteristics of Aircraft Deicing and Anti-icing Fluids BOD5 BOD20 Aquatic Ecotoxicity Acute Toxicity to Fish Acute Toxicity to Aquatic Inverts Toxicity to Aquatic Plants Brand Name FPD Manufacturer/ Distributor Product No. Specific Gravity COD (mg/L)
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2-13 BOD5 BOD20 Aquatic Ecotoxicity Acute Toxicity to Fish Acute Toxicity to Aquatic Inverts Toxicity to Aquatic Plants Brand Name FPD Manufacturer/ Distributor Product No. Specific Gravity COD (mg/L)
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From page 17... ...
2-14 Fate and Transport of Deicers An understanding of the mechanisms by which deicing products travel across the airport landscape and through the environment is necessary to fully understand their environmental implications. Deicers may follow several different fate and transport pathways after being applied.
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2-15 Mass balance data in the literature included aircraft deicers but not pavement deicers. Available mass balance–monitoring results suggest that onsite losses may account for between 20 and 75 percent of applied aircraft deicers, depending on the site-specific environmental conditions and infrastructure configuration.
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2-16 between the sites to 37 percent reduction in glycol in the 4-km stream reach between the airport outfall and the monitoring site (Corsi et al., 2006c)
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2-17 Biochemical Oxygen Demand Currently available aircraft fluids are based on either PG or EG, and the glycol is the predominant source of BOD. As a result, the BOD contents among aircraft deicing and antiicing fluids with the same glycol base are similar, with adjustment for glycol concentration (Table 2-12)
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2-18 driver behind stringent controls on deicing discharges from the Cincinnati–Northern Kentucky International Airport. The occurrence of bacterial growths associated with deicing discharges is not predictable, in large part because the controlling factors are very poorly understood.
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2-19 Aquatic Toxicity Aircraft Deicers and Anti-icers The aquatic toxicity of aircraft deicers and anti-icers has been documented through laboratory studies of the neat fluids (Kent et al., 1999) as well as some of the identified additives (Cancilla et al., 2003b; Cornell et al., 2000; Pillard et al., 2001)
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2-20 octylphenol (OP) are most readily available in the literature and have been reported to fall in the low milligram-per-liter range, with endocrine disruption also considered to be a factor at these levels (Staples et al., 2004, 1998; Van Miller and Staples, 2005)
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2-21 times. It was not possible to determine the fraction of Type I present as compared to that of Type IV, however.
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2-22 Recent Improvements in Environmental Characteristics Manufacturers constantly consider modifying formulations to improve performance, environmental characteristics, and cost. Several manufacturers have improved the toxicity of Type I formulations in recent years.
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2-23 • Monitoring data for FPDs of pavement deicers and anti-icers to represent a broad range of geographically diverse airport situations Characteristics of Deicers in Wastewater Treatment Systems For the purposes of this investigation, the treatability of deicer runoff is influenced by the organic constituents' biodegradability and toxicity. These two characteristics determine the basic types of treatment that can potentially be applied.
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2-24 as a route to the environment (Gruden and Hernandez, 2002)
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2-25 Airfield Electrical Systems Increased failure rates of airfield electrical components have been reported by some airports after changing from urea or glycol-based pavement deicers to potassium acetate. The issue appears to be directly related to the increased conductivity of potassium acetate solutions compared to that of urea and glycols.
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2-26 advantaged potassium formate– and acetate-based runway deicers were first introduced in Europe in 1988, before the widespread adoption of carbon brakes. In the Boeing and Airbus letter, it was reported that these PDMs appear to promote catalytic oxidation of carbon composite brake components, softening the carbon and possibly leading to brake failure.
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2-27 leaving a thickened fluid on the aircraft surface because of the high evaporation rate of the ADF and the cold surface. Similarly, the Battelle D3 fluid contained glycerol and some higher-molecular-weight sugars, which may have precipitated out on the cold aircraft surface.
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2-28 Foster-Miller Low-BOD Fluid Under SERDP sponsorship, Foster-Miller (Waltham, Mass.) developed new aircraft deicing and anti-icing fluids with the intention of providing high-performance environmentally advantaged options which can be safely released to the environment without post-treatment (Westmark et al., 2001)
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2-29 The U.S. Air Force evaluated METSS ADF-2 on KC-135R aircraft at the Niagara Falls Air Reserve Station.
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2-30 Further complication in transferring laboratory-generated BOD information to an environmental situation occurs because of the differences in environmental conditions between airport runoff and laboratory conditions of standard BOD5 tests. Deicing and antiicing activities occur typically during periods of colder temperatures and over longer periods of time than that do standard testing procedures; typically, microorganism populations are different too.
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2-31 TABLE 2-14 Examples of Recent Triazole Extraction and Analysis Methods Reference Matrix Extraction Analysis Gruden et al., 2001 wastewater sludge none HPLC-UV Pillard et al., 2001 water -- HPLC-UV Kolpin et al., 2002 water liquid/liquid GC/MS Cancilla et al., 2003a water SPE GC/MS fish liquid/liquid GC/MS Cancilla et al. 2003b water SPE GC/MS soil SPE GC/MS Corsi et al., 2003 water SPE GC/MS Breedveld et al., 2003 water SPE GC/MS soil -- LC/MS Castro et al., 2004 water -- HPLC-UV Hart et al., 2004 soil solution -- HPLC-UV Weiss and Reemtsma, 2005 water none/SPE LC/MS Corsi et al., 2006b water SPE GC/MS Corsi et al., 2006a deicers -- GC/FID Giger et al., 2006 water SPE LC/MS Reemtsma et al., 2006 water -- LC/MS Weiss et al., 2006 water none LC/MS Jia et al., 2007 soil -- UV-VIS Recently, the use of liquid chromatography–tandem mass spectrometry (LC/MS/MS)
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2-32 analysis, whereas Breedveld et al.
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2-33 TABLE 2-15 Examples of Recent APE Analysis Methods Reference Matrix Extraction Analysis Ding and Tzing, 1998 water wastewater SPE GC/MS Marcomini and Giger, 1987 sediment sludge soxhlet HPLCfluorescence Scarlett et al., 1994 wastewater gas-stripping HPLC-UV de Voogt et al., 1997 sediment sludge soxhlet GC/MS HPLC-UV Ding and Tzing, 1998 wastewater gas-stripping HPLC-UV Ahel et al., 2000 wastewater liquid/liquid HPLCfluorescence Crescenzi et al., 1995 water wastewater SPE HPLC-MS Shang et al., 1999 sediment soxhlet HPLC-MS Ferguson et al., 2000 water sediment SPE sonication HPLC-MS Ferguson et al., 2001 wastewater sediment SPE sonication HPLC-MS Loyo-Rosales et al., 2003 water sediment SPE soxhlet HPLC-MS/MS Previous work on APE occurrence in deicers and impacted environmental samples (e.g., runoff and snow banks at airports) (Corsi et al., 2003, 2006b)
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2-34 Toxicity Test Methods Airport deicing discharges are regulated under the Clean Water Act through permits issued under the National Pollutant Discharge Elimination System (NPDES)
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2-35 AMS standards relating to aircraft and runway deicing and anti-icing fluids and runway solids are given in Table 2-16. TABLE 2-16 Standards for Aircraft and Runway Deicing/Anti-icing Fluids and Runway Solids Document Revision Publication Date Document Title AMS 1424 H July 2007 Deicing/Anti-Icing Fluid, Aircraft, SAE Type I AMS 1425 C January 1995 Deicing Fluid, Aircraft, Ethylene Glycol Base AMS 1426 C October 1993 Fluid, Deicing/Anti-Icing, Runways and Taxiways Glycol Base AMS 1427 A January 1995 Deicing/Anti-Icing Fluid, Aircraft, Propylene-Glycol Base AMS 1428 F July 2007 Fluid, Aircraft Deicing/Anti-Icing, Non-Newtonian (Pseudoplastic)
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2-36 TABLE 2-17 AMS Requirements for the Most Common Aircraft and Runway Deicing/Anti-icing Liquids AMS 1424H 1428F 1431B 1435A Trace Contaminants X X X X Phase Diagram -- -- X -- Chemical Analysis -- -- X -- Physical Properties (APHA) Flash Point (ASTM D93, D3278)
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From page 40... ...
2-37 TABLE 2-17 AMS Requirements for the Most Common Aircraft and Runway Deicing/Anti-icing Liquids AMS 1424H 1428F 1431B 1435A Responsibility for Inspection X X X X Classification of Tests X X X X Acceptance Tests X X X X Periodic Tests X X X X Preproduction Tests X X X X Sampling and Testing X X X X Bulk Shipments (ASTM D4177) X X -- X Drum Shipments (ASTM D1568)
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