Do’s & Don’ts of Storage & Handling of Asphalt Emulsions

DO

• Set the clearance on pumps for emulsions to prevent binding and to prevent breaking of the emulsion.
• Clear lines, valves, and pumps of emulsion.
• Drain pumps and remove plugs during freezing weather. No. 1 or No. 2 fuel oil may be used to keep pumps free.
• Warm the pump casings and packing glands to 150°F (65°C) to ease start up.
• Store emulsions in vertical tanks to prevent excessive skin formation.
• Store emulsions at the temperature specified for the particular grade and application.
• Store emulsion in insulated tanks to protect from freezing and make most efficient use of heat.
• Use large, side-mounted, slow moving propellers, mounted 3 feet from the bottom of the tank to “roll” the emulsion to prevent skin from forming if skin formation is an issue. Over-mixing should be avoided.
• Gently circulate emulsions when heating or after prolonged storage.
• Place inlet and return lines near the bottom of the tank to prevent foaming.
• Pump from the bottom of the tank to minimize contamination from skinning that may have formed.
• Check compatibility of water and emulsion in a flask prior to larger volume use.
• Dilute medium and slow-setting emulsions by adding warm water to the emulsion.
• Provide adequate ventilation.
• Drain tanks to no measurable quantity before adding an emulsion of different type. Emulsions with the same designation may be very different in performance.
• Heat only to reasonable temperatures.
• Haul emulsion in truck transports with baffle plates to prevent sloshing.

DON’T

• Use tight clearance pumps; they may seize.
• Leave emulsion in pumps, valves or lines during freezing weather.
• Hold emulsions in lines and pumps for extended periods.
• Apply severe heat to pump casings or packing glands. The pump may be damaged, and the emulsion may break.
• Allow heating surfaces to exceed 185°F (85°C). This will cause emulsion to break on the heating surface.
• Store emulsions in horizontal tanks.
• Circulate emulsions excessively. Emulsions tend to lose viscosity when pumped. Air may also become entrained and lead to an unstable emulsion. Excessive pumping may also lead to the emulsion breaking.
• Use forced air to agitate emulsions.
• Dilute rapid-setting emulsions with water.
• Never add emulsion to water.
• Dilute emulsions with non-potable water or cold water.
• Dilute emulsions with fuel oil, diesel fuel, or kerosene.
• Put fuel oil, diesel fuel, or kerosene on top of a tank of emulsion to prevent skin from forming.
• Pump emulsions into open air or have inlet lines near the top of the tank.
• Place outlet lines in mid tank.
• Subject emulsion or the open air above it to open flame or strong oxidants. Never heat the emulsion over 190°F (88°C).
• Mix emulsions of different chemical types, classes, grades, or designations in storage tanks, trailers, transports, or distributors. Anionic and cationic emulsions may coagulate when mixed.
• Load emulsion into storage tanks, tank cars, tank transporters, or distributors containing remains of an incompatible material.
• Proceed if you have questions.