About Asphalt in General

http://en.wikipedia.org/wiki/Asphalt

All About Asphalt

Asphalt is a sticky, black and highly viscous liquid or semi-solid that is present in most crude petroleums and in some natural deposits sometimes termed asphaltum.

In U.S. terminology, asphalt (or asphalt cement) is the carefully refined residue from the distillation process of selected crude oils. Outside North America, the product is called bitumen.

The primary use of asphalt is in road construction, where it is used as the glue or binder for the aggregate particles. The road surfacing material is usually called 'asphaltic concrete' or simply AC in North America, or simply 'asphalt' elsewhere. Within North America the apparent interchangeability of the words 'asphalt' and 'bitumen' causes confusion outside the road construction industry despite quite clear definitions within industry circles.

Asphalt is typically stored and transported at temperatures around 300 degrees Fahrenheit (150° C). Sometimes diesel oil or kerosene are mixed in before shipping to retain liquidity; upon delivery, these lighter materials are separated out of the mixture. This mixture is often called bitumen feedstock, or BFS. Some dump trucks route the hot engine exhaust through pipes in the dump body to keep the material warm. The backs of tippers carrying asphalt, as well as some handling equipment, are also commonly sprayed with a releasing agent before filling to aid release. Diesel oil is sometimes used as a release agent, although it can mix with and thereby reduce the quality of the asphalt.

Ecological Bio Asphalt and Environmental Positives of Asphalt –

Going Green With Asphalt http://asphaltroads.org/Environment

Go Green with Asphalt - Asphalt recycling has been prevalent throughout the country since the 1970s. Since at least 1996, asphalt pavement has been — and remains — America’s most recycled product. The asphalt industry reclaims more than 90 million tons of pavement every year, and recycles 80 percent of that amount.

More information available at the National Asphalt Pavement Association’s Web site at http://www.hotmix.org/

Environmental Friendly Non - Petroleum Based Asphalt?

The world has become increasingly concerned over the global peak oil and perceived climate change problem in recent years due to the pollution that is released into the atmosphere. Most of the emissions are derived primarily from burning fossil fuels. This has led to the introduction of petroleum bitumen alternatives that are more environmentally friendly and non toxic. Bitumen can now be made from non-petroleum based renewable resources (bioasphalt).

Bioasphalt is still in the EXPERIMENTAL STAGE but it is an aphalt alternative made from bitumen from non-petroleum based renewable resources.

These sources includes sugar, molasses, rice, corn, and potato starches, natural tree and gum resins, natural latex rubber and vegetable oils, lignin, cellulose, palm oil waste, coconut waste, peanut oil waste, canola oil waste, potato starch, dried sewerage effluent and so on. Bitumen can also be made from waste vacuum tower bottoms produced in the process of cleaning used motor oils, which are normally burned or dumped into land fills.

A number of homeowners seeking an environmentally-friendly alternative to asphalt for paving have experimented with waste vegetable oil as a binder for driveways and parking areas in single-family applications. The earliest known test occurred in 2002 in Ohio, where the homeowner combined waste vegetable oil with dry aggregate to create a low-cost and non-polluting paving material for his 200-foot driveway.

Shell Oil Company paved two public roads in Norway in 2007 with vegetable-oil-based asphalt. Results of this study are still premature

http://www-static.shell.com/static/bitumen/downloads/technical_papers_0507.pdf