The Asphalt Bitumen Story

Approximately 2000 million tonnes of Asphalt Bitumen is used annually around the world and its use will grow dramatically especially in Asia during the next decade. Bitumen has been around for millions of years in crude oil, it won't last forever if not for its negative environmental impact but because its source is slowly being depleted. A number of factors have an effect on the performance of asphalt, these include its composition and crude oil source, the type and amount of aggregate used, the presence of moisture, the method of road construction, temperature and of course the volume of traffic.

Around 30% of the world crude oil supply is heavy grade which is required to manufacture bitumen, it is a costly exercise for the oil industry having to spend roughly two barrels of fuel to extract one barrel of heavy grade crude oil from the ground, most of the cost goes into heating the wells, pipelines and into transportation which all at the end of the day are ultimately carried at the expense to people's health and the environment.

Conventionally the asphalt manufacturing process has to be monitored very closely to achieve a positive paving outcome and is generally un-forgiving to minor changes to the bitumen or aggregate loading and processing temperatures. The chance of asphalt mix failure is therefore increased due to human or mechanical error, normal road grade bitumen is made from the by-product (bottoms) of the petrochemical distillation process this by-product is processed further by adding oils and cutters (volatiles) to achieve a desired grade. The fumes that are emitted into the atmosphere during the bitumen manufacturing process, hot storage and at the asphalt manufacturing stage not only have a negative impact on health but are also environmentally damaging and therefore undesirable.

The surfaces of asphalt roads made from normal bitumen have a tendency of becoming greasy under wet weather conditions, this is due ironically to the high oil content of residue bitumen. Moving traffic tends to pick up (binder shift) this oily residue and distribute it from one area to another and consequently contribute to the slippery road surfaces. Considering all the shortcomings of residue bitumen and its impact on the environment (source) and the asphalt work force, and also taking into consideration the global move towards renewable resources and sustainability, there is a pressing need to revitalize research, development and engineering especially into alternative asphalt bitumen compositions and asphalt materials. Ecopave Australia is hoping to contribute and answer some of the problems that have surrounded petroleum based bitumen, by introducing the GEO320 MRH asphalt and bitumen technologies.

WARMING

WARMING