Step Up Hot-Mix Production with Your Facility’s Own Crushing Plant
BY Daniel C. Friedman
Editor’s Note: For 2024, AsphaltPro Magazine allows experts in the industry to share how to expand your operations to the next phase of business. Are you ready to process your own recycled asphalt pavement (RAP) for your hot-mix asphalt (HMA) production? Let’s turn to some professionals who have equipment, services, software and tenure to help you expand to mix design, production, hauling and more. This month’s installment from Eagle Crusher takes an overarching look at the environmentally responsible task of adding recycling operations to your business.
If you don’t already have a recycled asphalt pavement (RAP) crushing plant to make your own crushed asphalt, you can take your production to the next level by adding a crusher to your operation. The benefits to your business can create a real boon for revenues and profits. Here, we outline the benefits and provide considerations to help determine if your own RAP crushing plant is right for you.
A primary consideration and a good starting point is the type of crusher that will be most beneficial to how your facility operates.
There are many benefits to adding your own RAP crushing plant to aid in the production of your hot mix. Adding a RAP crushing plant to your asphalt production facility can help:
- save on material costs by producing RAP onsite compared to having a third-party deliver RAP to your facility, paying for an outside firm to crush RAP on your own site, or utilizing only virgin material;
- improve production control and efficiency by not relying on outside vendors’ schedules;
- increase revenues by accepting asphalt tear outs and millings from others; and
- maintain control over your mix quality and mix specs with production of your own high-quality RAP based on having the right equipment for the job.
One of the benefits of having your own recycle processing operation is the ability to crush and screen material at your leisure and to your own specifications. Here a wheel loader feeds material for the E-Plant Triple Deck from Eagle Crusher.
Several factors play into the decision of whether adding your own RAP crushing plant makes sense for your business. These include:
- Market size
- Crusher location
- Crusher types and features
- Initial Investment and ROI
Market Size
Market size is important in considering whether you can realistically sell more asphalt. Are there enough commercial and residential paving companies in the area to buy the extra mix you may be able to produce? How many more contracts could you potentially be awarded by having better control and better quality of your hot-mix production? Is your market large enough that you can obtain the RAP you need to produce crushed asphalt for your own mix use? Is there enough current and future residential and commercial market growth, and therefore paving demand in the market, to help you sell more?
When setting up the RAP crusher, pay attention to the detail of skirting to mitigate dust. In these images you see the conveyor from under the UM-25 Impactor crusher. It feeds back onto the conveyor to be rescreened. All photos courtesy of Eagle Crusher
Crusher Location
You need to consider the location of your crushing plant should you decide to add a RAP crusher to your asphalt production operation. A primary consideration and a good starting point is the type of crusher that will be most beneficial to how your facility operates—such as whether your asphalt production uses stationary hot-mix plants to produce at one, on-site location or portable asphalt plants that move from site to site.
When deciding where to place the crusher in your yard, a good starting point is to consider the type of crusher that will be most beneficial to how your facility operates. Its size and configuration will help you decide where it should be located.
Other considerations are permitting and transport. Permitting rules and fees vary greatly from one locality to another and are different state-by-state, as well. Permit regulations may also differ based on whether you are opting for a stationary crusher permit or a portable crusher permit. Additionally, local environmental regulations may affect an operation’s ability to obtain a permit, depending on the specific crusher specifications for which a business is applying. Acquiring a permit can take time, so it’s important to plan ahead and start the process early.
When it comes to portable crushers leaving their first jobsite to go to another locale, crushers may be permitted for one main location, and then, depending on the state or locale, subsequent temporary permits to move the crusher to different sites may be more easily obtained or may not even be required. You will want to research all of this based on your location.
When setting up the RAP crusher, also pay attention to details like installing magnets to remove any last-minute deleterious material. In this image, you see a magnet affixed over the crusher discharge conveyor of the E-Plant. Material then falls onto the 5X16 triple-deck screen for precise sizing.
Crusher Types and Features
If you are a start-up asphalt production facility and deciding on whether your operation will use portable or stationary asphalt crushing plants, consider that portable asphalt operations are best in areas where jobs are a considerable distance apart, a market has minimal growth and small population density, and where workloads shift from one area to another due to seasonal factors.
It follows that the type of crusher you choose will match what you choose for your hot-mix production, either portable or stationary. Beyond portable and stationary crushers, choosing the perfect crusher type for RAP crushing comes down to the specific features of the available types of crushers—jaws, cones and impact crushers. Impact crushers are typically the best choice for RAP crushing to achieve the highest quality end-product and the necessary production capacity to keep high-quality hot mix flowing.
Impact crushers use a simpler design comprised of a rotor and two bearings that spin to launch the RAP against a curtain or apron. The simplicity of an impactor like the Eagle Crusher three-bar, solid-steel, sculptured rotor works to explode the RAP with the force of the blow bars and launching it into the primary curtain at the proper angle, then smashing it again with the secondary curtain liners to prepare it for its final reduction, creating a very consistent mix to be sent on to the drum as a more structurally sound cubical product.
Jaw and cone crushers on the other hand utilize compression to crush, which can be advantageous when crushing hard rock from quarries. Asphalt crushing isn’t about crushing the rock, but instead about separating the asphalt bonds. When RAP is compressed, it can more easily fracture, exposing white rock and requiring more liquid asphalt to restore the full coating.
There are other issues with jaw and cone crushers, as well. Cone crushers have a significantly smaller feed material size range, meaning they can generally only be fed millings or material that has already been processed, like through a jaw crusher, requiring additional crushing equipment. Jaw crushers are limited on their final output size and cannot produce a cubical product, thus requiring further processing with another piece of equipment, like through a cone crusher.
Realizing that impact crushers are typically a producer’s best bet for crushing RAP, keep in mind that a properly sized and type of screen is critical to any RAP operation. Asphalt producers are typically making finer sizes than other types of aggregate and recycling production. For RAP, the screen is the determining factor for net production. If RAP can’t be screened, it probably can’t be used.
Eagle Crusher Company Displays UltraMax® 1600X-OC Portable Impactor Plant
So, let’s explore the features of both stationary and portable RAP crushers. Consider looking for stationary crushers like the Eagle Crusher MaxRap® system, which is designed to crush and screen RAP for product consistency, productivity and profitability, using its UltraMax® impactor.
MaxRap can integrate with any asphalt plant automation. It allows operators to switch from top to base material production from the control house, and most importantly, it produces highly uniform cubicle spec product with a minimum of white rock and a minimum of fines.
Actuated diverter chute work allows multi-feature deck selection, blending, and bypass while the calibration chute for sampling verifies that the mix-design spec requirement is correct. The side discharge conveyor from the crusher may be used for stockpiling or returned to another conveyor for re-circulating back to the plant screen for resizing, and with the system’s ability to screen only, all material can be conveyed to stockpile. The under-screen product conveyor to cross conveyor feeds to the drum mix feed conveyor of the asphalt plant for final processing and mixing.
A versatile and reliable portable RAP crusher should be able to provide the same precision crushing of a stationary crusher, while allowing operators to crush RAP at multiple locations. Such is the case with Eagle Crusher’s new MaxRap 25 Portable.
The savvy asphalt mix supplier can be more precise in mix production when he directs crushed and screened product into specific stockpiles or when he conveys it directly to cold feed bins for production.
Initial Investment and ROI
How do all of these considerations factor together to determine if adding a RAP crusher to your asphalt production facility makes sense financially?
First, with a crusher like Eagle Crusher’s MaxRap or MaxRap 25 Portable, one crusher replaces jaw, cone and screen multi-unit systems for a lower initial investment while maintaining high production of cubical spec product. Choosing a jaw crusher instead of an impact crusher requires additional equipment, like a cone crusher following the jaw, and in some instances, a vertical shaft impactor (VSI) to make a spec final product. This is because using a jaw crusher in a RAP circuit is for primary reduction only, then prepping RAP for a cone crusher, whereas using an impact crusher for most RAP applications requires only one crusher. Two may be necessary where very high capacity or special products are required.
Even if the cost of one impact crusher or crushing system is more than the cost of a jaw, cone and vertical shaft impactor combined, more and different pieces of equipment opens the door for more mechanical issues and more down time, versus keeping production high, and as previously discussed, the higher quality mix and the ability to have spec product high, as well. In most cases, however, the initial investment for an impact crusher versus two to three different crusher types pays for itself more quickly and improves ROI based on fuel savings and maintenance costs, among other factors.
The service friendly design of RAP crushers like the Eagle Crusher brand can help with time and labor costs and less down time while screening. The screening process can continue while the crusher is removed from the circuit. The screen chute system folds out of the way for ease of changing the screen cloth, and screen service platforms are positioned on both sides of the screen for ease of maintenance. All of this adds up to time and labor efficiencies and a better bottom line.
Additionally, quality hot mix via crushing your own RAP with an impact crusher leads to new customer potential and repeat customers, adding to greater revenues and increased products. This is because RAP impact crushers lead to higher quality mix by separating the binding matrix, airing out the material releasing moisture, making for a drier material going into the hot mix. Drier material saves energy as it eliminates the need for more fuel in the burner.
All things considered, it is worth considering whether it’s time to add a RAP crusher to your asphalt production facility. We hope this helps get you started.
Daniel C. Friedman is the vice president of marketing at Eagle Crusher Co. Inc., Galion, Ohio.