The potential for blending residuals to create valuable products that are publicly accepted is an example of recycling at its best. Previously, much of the research done on reuse of residuals has centered on potential negative effects. Generally, blending of materials has been done in a relatively haphazard fashion. There is a growing understanding that residuals can be deliberately mixed for specific end uses. This is the initial phase of transition from residuals disposal to product development. The XXII Annual Beltsville Symposium focused on the range of factors that need to be taken into...

Co-utilization or blending of residuals offers a unique opportunity to develop products with particular characteristics that are able to target specific customer needs. The very notion of deliberately blending by-products suggests that the recycling and beneficial reuse industries are taking a quantitative step forward towards developing products rather than simply reusing residuals. At the same time that this step provides unique opportunities, it also presents unique challenges. The science associated with the beneficial use of one product may not apply when that product is mixed with...