Recycling concrete and asphalt rubble and demolition debris can be a very profitable addition to an aggregates producer's competitive arsenal, as many have discovered in recent years. In fact, a road-portable recycling system could pay for itself with one large job. Most aggregates producers who also recycle are utilizing a two-pronged recycling strategy: crushing 1) at their quarries and 2) at demolition/construction sites.

Aggregates producers invite area contractors to haul rubble to their quarries and dump it. This is a ready source of material to be recycled and sold along with aggregates. The contractors benefit by having their choice of the closest quarry dump sites, and can have their trucks return loaded with aggregates or recycled materials instead of coming home empty from a landfill.

A road-portable recycling plant also can be set up at or near building or road demolition/construction projects to crush rubble on site, where it can be used immediately as fill or base materials. This eliminates or reduces the need for landfill hauling and hauling in aggregates from a distant quarry, providing three major benefits: 1) It cuts trucking costs. 2) It saves time and speeds production, cutting labor and other costs. 3) It can eliminate or reduce complaints from citizens, businesses and local government regarding traffic congestion and dirt/mud tracked onto roads and streets by a steady stream of noisy trucks. Trucks are largely restricted to off-road travel or short road hauls.

To determine the viability of recycling for your operation, you first need to evaluate the market in your area and determine the size of recycling plant you'll need. Will you be handling large jobs on site, such as the demolition of building complexes or highways? Or will you be recycling mainly in your quarries? How often will you have to move your plant, and will it operate in the wide-open spaces or crowded urban settings where the tonnage may be less and getting in and out quickly is vital?

Large road-portable plants can crush concrete and asphalt rubble at up to 600 tons per hour or more. These systems normally consist of a rubble crusher, side discharge conveyor, screening plant, and a return conveyor from the screen to the crusher inlet for reprocessing oversize materials. An experienced crew can set up or tear down a well-designed, highly mobile system in eight to twelve hours without the need for a crane. Other systems can take two or three times as long and require crane assist.

At the other end of the spectrum is the compact, self-contained mini-crusher that fits nicely into cramped quarters, handles up to 150 tons per hour and sets up, ready to run, in about 15 minutes. This type of plant offers extreme mobility and can operate at more than one site per day.

Equipment manufacturers can help you determine the right size plant for you. In addition, it is extremely important to talk to experienced users of the plant you may be considering. Be wary of manufacturers who won't willingly give you a customer contact list.

Regardless of the size of your operation, the crusher absolutely must be a primary impactor designed for recycling. A jaw crusher simply cannot compete with an impactor in recycling. Impactors are faster, more efficient, can crush a greater variety of materials, and give you greater control over product size. Because of its large reduction ratio-as much as 30 to 1 in closed circuit-a primary impactor normally needs no secondary crusher. And it shatters concrete, leaving steel mesh and rebar virtually concrete-free and ready for sale to metals recyclers.

Aggregates producers are now also finding road-portable primary impactors superior to jaw crushers for high-capacity crushing of limestone with normal or lower silica content. Typically the impactor is used both for aggregates and recycling, giving the operator two-way profit potentials. It just might be something you should look into.