On-Site's Construction Forum
Customizing a road-portable concrete-recycling system
A custom plant can make up for its extra cost in higher efficiency.
There are four major considerations in specifying a road-portable concrete/asphalt recycling system to meet your specialized needs:
- Determine your needs and evaluate the ability of standard, off-the-shelf equipment to meet those needs.
- Consider ways to customize the equipment, then evaluate the benefits compared to the standard system.
- Find a manufacturer that has the will, the capability and the experience to design and build the specialized system you want, and can advise you on ways to improve it.
- Evaluate the purchase and operating costs of the specialized system versus the standard equipment.
Customizing may cost you a lot less than you would expect. Plus it may easily pay for itself in a short time and be far more profitable over the years than an off-the-shelf plant.
Customizing may include:
- hydraulic clamping and fastening mechanisms or quick-disconnect pins instead of bolts for faster setup and tear down of the crushing and screening plants.
- a longer feeder on the crusher.
- an enclosed, specially designed cab that enables the operator to monitor and operate all crushing/screening/conveying systems and receive data from weigh scales on the transfer conveyors.
- radial stackers that can be raised or lowered hydraulically from the operator’s station.
solid, reinforced steel side panels on the crushing plant to prevent material from invading interior areas and breaking hoses or damaging mechanisms. - an ISO-certified interior shell in the control trailer for sound suppression of the generator and motor.
- in addition to the electromagnetic separator on the crusher discharge conveyor, you also could have integral secondary and tertiary magnets on transfer conveyors, removing about 98 per cent of remaining ferrous particles.
You might want a crushing plant where you designate or provide the new or used crusher you want mounted on the road-portable or pit-portable chassis. Another example is a double pre-filter on the generator engine, to prevent dust damage. Or controls where the operator can switch from generator power to electric utility line power by simply throwing a switch. Key structural members of the crushing plant, screen plant and conveyors can be customized for greater strength and stability under extreme load conditions. And so on. There are endless possibilities that could make your recycling system better for your particular operation.
Finding a manufacturer that can and will customize a plant for you isn’t always as easy as you might think. Building a standard system is easier and often more profitable. Customizing may tie up engineers and/or slow the production line. And an inexperienced customizer may not know how to go about it properly, efficiently, or in your best interest. Generally, the bigger the manufacturer, the more they may resist customizing. Also, it may cost a lot more, take longer to manufacture, and you still may not get exactly what you want.
The manufacturer should be able to design and build to your specifications or do the design work for you. Their engineers should investigate equipment processes, plus recent developments and innovations related to your type of operation. They should be able to do material analyses, product specifications tests and system capacity checks. They should create flow charts to show how the system will work, including all components and their production capabilities.
The manufacturer should specify equipment, itemize costs and spell out any options to show cost versus benefits. They should provide operation and maintenance manuals custom written for your system and be able to train your production and service personnel.
Any manufacturer can install a crusher on a chassis. But will the plant be professionally engineered? The weight and balance calculations must be right for over-the-road travel, and for the highway regulations in your state(s). The design should normally incorporate features such as a rock box type inlet and discharge chutes for long life with minimum maintenance.
And make sure the manufacturer is not using the lowest priced components to reduce his costs or make your cost seem more palatable. Heavy-duty components will pay off for you in the near term and the long run both. Usually, the biggest factor in recycling profits is downtime. So quality design, construction and simplified maintenance are vitally important.
Is the manufacturer’s experience primarily in recycling or aggregates? Can the manufacturer also provide a road-portable screen plant, conveyors, stackers and control system to meet your needs? The equipment should be designed and sealed with features such as belt covers and screen skirts to avoid leakage and resultant clean-up problems. And all equipment should be operated from one control station for efficiency and safety. An experienced supplier can advise you on these and other pertinent matters.
Any concrete/asphalt rubble plant, whether standard or custom, should normally utilize a primary impact crusher designed for recycling. Jaw crushers have their place when crushing hard/abrasive material, but do not have the reduction ratio an impactor has, plus an impactor is better at liberating rebar and mesh from concrete.
Even if you want to crush both concrete/asphalt rubble and limestone with your plant, which is becoming more prevalent among aggregates producers, a primary impactor is probably still the right plant for you. An impactor can be more efficient and lower-cost than a jaw or jaw/cone system for crushing limestone with low to medium hardness. So be sure your customer has major experience with impactors as well as jaw crushers.
But no matter which manufacturer you may be considering, ask how many custom recycling systems they have built and how many are still operating. And always talk to some long-time owners of those custom plants regarding their efficiency, durability, maintenance and whether the manufacturer customized them properly, on time and within budget.
Chances are that a custom recycling system will meet your needs better than standard, off-the-shelf equipment, and the extra that it costs will pay for itself handsomely. The guidelines set forth here can help you get such a system.
Grasan designs and manufactures equipment and systems for recycling concrete and asphalt rubble and C&D debris; crushing, screening, handling and storage of aggregates; conveying and stacking of materials; and special applications in bulk material handling and processing.