Environmental assessment of a performance grade asphalt modifier developed from recycled lubricating oil
Description
The purpose of this research was to examine the environmental impacts and risks associated with the production and use of a Performance Grade modifier from the re-refining process for recycled used lubricating oils. Life cycle assessment was used as a tool to assess the environmental impacts of four re-refining processes which produce an asphalt flux that is used as an asphalt cement extender and/or roofing asphalt extender. The four processes are: (1) Evergreen Oil, (2) Safety-Kleen, (3) deMenno/Kerdoon and (4) Chevron Trailblazer. On the basis of the assessment, the Chevron process is the closest to the 'future industrial practices' described by pollution prevention. Although the Chevron process is more energy intensive than the other three, it has the lowest emissions rate and does not generate wastewater or hazardous wastes. The life cycle comes full circle, i.e., the future industrial practices are achieved whereby most process waste production is eliminated, and as much remaining waste as possible is recycled, reused or reclaimed at the facility of origin or another facility. The Safety-Kleen process has the lowest energy consumption per gallon of used lubricating oil processed, as well as the lowest volume ratio of waste generated after Chevron's. The contribution to the body of knowledge is a life cycle assessment and health risk assessment for the manufacture and application of a modified Performance Grade asphalt using recycled used lubricating oil. The inventory assessment can be added to the U.S. EPA's Life Cycle Inventory database. The improvement assessment component of the Life Cycle Assessment was then used to assess the use of the asphalt flux from the Chevron Trailblazer process as a Performance Grade modifier in the production of Performance Grade asphalt. The use of the Performance Grade modifier produces a Performance Grade asphalt which is adaptable to a variety of environments and is effective over a wide range of temperatures, whereby the decrease in the upper and lower limits of the temperature range occurs in a ratio less than about 2 to 1, in about a 1 to 1 ratio. It further provides a method for producing such a Performance Grade asphalt. The ratio closest to 1 to 1 is the most desired and represents that for each degree achieved at lower temperature, the high temperature will also decrease by only one degree. It should be apparent that the Performance Grade modifier may be used to increase efficiency, lower production costs and simplify the production of Performance Grade asphalt. The contribution to knowledge was a U.S. Patent, 'Performance Grade Asphalt and Methods for Producing the Same'. (Abstract shortened by UMI.)