Presentation on theme: "Module 2: Chemical and Physical Characteristics of Ethanol and Hydrocarbon Fuels."— Presentation transcript:
Module 2: Chemical and Physical Characteristics of Ethanol and Hydrocarbon Fuels
2 Objective Upon the successful completion of this module, participants will be able to describe the chemical and physical differences between pure gasoline and gasoline / ethanol-blended fuels.
3 Introduction Characteristics of polar solvents & hydrocarbons, their differences, & how they interact Conditions under which ethanol-blended fuels will retain certain characteristics of types of fuel Help emergency responders mitigate various incidents according to conditions found
4 Activity 2.1 Definitions Purpose: –To allow participants to identify the definitions related to ethanol & ethanol- blended fuels.
5 Characteristics of Gasoline (A Hydrocarbon) Similar characteristics whether flammable / combustible liquids Produced from crude oil by fractional distillation Immiscible Flash point -45°F
6 Characteristics of Gasoline (A Hydrocarbon) Vapor density between 3 & 4: –Gasoline vapors seek low levels / remain close to ground level Specific gravity of 0.70–0.78: –Will float on top of water Auto-ignition temperature > 530°F Boiling point between 85°F & 437°F
7 Characteristics of Gasoline (A Hydrocarbon) Not considered poisonous for placarding purposes: –Harmful effects after long-term & high-level exposure –Can lead to respiratory failure Smoke from burning gasoline is black & has toxic components Greatest hazard is flammability: –Fairly narrow range of flammability
9 Characteristics of Pure Ethanol (A Polar Solvent) Ethanol used with motor fuels must be denatured with 2–5% gasoline / similar hydrocarbon before transport to bulk storage facilities Denaturant has minimal effects on characteristics
10 Characteristics of Pure Ethanol (A Polar Solvent) Renewable fuel source produced by fermentation & distillation process Most common source in U.S. is corn Polar solvent Totally miscible Flash point 54°F Property of Wikimedia ® Commons, reprinted with permission
11 Characteristics of Pure Ethanol (A Polar Solvent) Vapor density of 1.60: –Heavier than air –Vapors do not rise Specific gravity 0.79: –Lighter than water –Miscible: thoroughly mix with water Auto-ignition temperature 685°F
12 Characteristics of Pure Ethanol (A Polar Solvent) Boiling point 173°F Less toxic than gasoline / methanol Carcinogenic compounds not present in pure ethanol Greatest hazard as motor fuel component is flammability: –Wider flammable range than gasoline: (3.3–19%)
Flash Point Exercise 2.4% denatured (E-98) ethanol 15°F temperature 13 Property of Steve Hergenreter, reprinted with permission
Video Watch the video clip Flash Point Test: –Ethanol with an MSDS-listed flash point of 49°F being lit at 15°F 14 Property of Wikimedia ® Commons, reprinted with permission
15 Copyright 2009, IAFC
16 Characteristics of Pure Ethanol (A Polar Solvent) In pure form no visible smoke & visible flame In denatured form little to no smoke & slight orange flame will be visible Ethanol & some ethanol blends can conduct electricity Large amounts of water required to dilute ethanol to no longer support combustion
Invisible Flames Pure Ethanol Incorporate use of thermal imaging camera into SOPs Taken at a foam comparison exercise Shot taken after non-AR foam dissolved Watch the video clip Invisible Fire: E Copyright 2009, IAFC
Shot of Ethanol Fire Through Thermal Imaging Camera 18 Property of Steve Hergenreter, reprinted with permission
19 Activity 2.2 Comparison of Gasoline and Pure Ethanol Purpose: –To allow participants to discuss the differences & similarities in the chemical & physical properties of pure ethanol & gasoline.
20 Characteristics of Ethanol-Blended Fuels Ethanol increases the ability of gasoline to burn cleaner: –Lower emissions from unburned hydrocarbons Minimal amounts of water will draw ethanol out of blend away from gasoline: –Ethanol & gasoline more suspension than solution
21 Characteristics of Ethanol-Blended Fuels Gasoline floating on layer of ethanol / water solution –Resulting ethanol / water solution still flammable Property of Wikimedia ® Commons, reprinted with permission
22 Characteristics of Ethanol-Blended Fuels Blending fuels alters physical & chemical characteristics of original fuels: –Visual difference of smoke & flame characteristics: Higher content of ethanol, less visible black smoke content & orange flame production
23 Characteristics of Ethanol-Blended Fuels Blending fuels alters physical & chemical characteristics of original fuels: –When foam / water flowed on burning product, gasoline tends to burn off first: May have no visible smoke as the hydrocarbon burns off leaving only the ethanol burning
24 Summary Polar solvent miscible & flammable When blended with gasoline, produces slightly cleaner burn than gasoline alone Blend of gasoline & ethanol can easily go unnoticed by emergency responders: –Ethanol will be last fuel to burn –Ethanol can burn without visible smoke