MOVING BINDER
INNOVATION FORWARD SAMI BITUMEN HAS DEVELOPED A LOW VISCOSITY CRUMB RUBBER BINDER THAT CAN BE SPRAYED DURING THE COOL PERIODS OF THE YEAR FEATURING A SIGNIFICANT REDUCTION IN THE USE OF KEROSENE. WE SPEAK TO PRIMAL SURFACING, A COMPANY USING THE PRODUCT DUE TO ITS SAFETY AND ENVIRONMENTAL BENEFITS.
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ommonly used in crumb rubber binders as a cutter, kerosene can generate fumes which contribute to pollution, acid rain and greenhouse gas emissions. For spray sealing applications kerosene can improve the binder wetting of the aggregates to create a better-quality road. It also reduces the bitumen’s viscosity to ensure it is fluid enough to be sprayed evenly onto the surface without streaking. However, SAMI Bitumen has created a low viscosity crumb rubber binder capable of achieving these outcomes without using a kerosene cutter for the most part of the year and with a significant reduction in the use of kerosene during winter time. Iulian Man, SAMI Bitumen Technical Primal Surfacing’s OVB production unit.
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ROADS AUGUST 2020
Services Manager, says the company recognised that if it could create a crumb rubber binder without kerosene that has low viscosity, it could help to improve the environment without compromising the spray seal performance. In order to create the low viscosity binder, the SAMI Bitumen team performed chemical modifications to produce the right formulation. “We basically reengineered the formula
of our standard crumb rubber binder in order to lower the viscosity and create the new, a more fluid crumb rubber binder. No fluxant additives were used in the process” Mr. Man says. “We got to a stage where we have created a crumb rubber binder that doesn’t need any cutter or very little during winter applications.” Elimination or significant reduction of kerosene in the binder can also reduce
“FOR A SPRAY SEAL, THE ABILITY FOR A BINDER TO RETAIN THE AGGREGATE IS THE MOST IMPORTANT ASPECT FOR THE PERFORMANCE OF THE ROAD. PREVENTION OF AGGREGATE STRIPPING IMPROVES A PAVEMENT’S LIFE CYCLE OUTCOMES.”
