An overhead view of the Bronx County Recycling crushing spread.
Salvatore Cascino, owner, and Vincent Grottola, facility superintendent, both of Bronx County Recycling, wanted to produce a cleaner, higher-quality end product for their customers.
Bronx County Recycling, as its name implies, is located in the Bronx, N.Y., within a few blocks of Yankee Stadium on a modest five-acre parcel. The 20-year-old company accepts almost any recyclable concrete, asphalt or dirt that needs disposing of in Bronx County and the surrounding area. Materials come in from a 20-to-30-mile radius of the facility, carried in by hundreds of truckloads each day and approximately 1,500 to 2,000 cu. yds. (1,146 to 1,529 cu m) is processed, recycled and turned into useful construction materials that are re-used in the New York City metro area.
Bronx County Recycling produces 4-inch minus crusher run, item four road base, 1 3/4-inch recycled stone, 3/4-inch recycled stone; 3/4-inch blue stone, brown sand, concrete sand, mason sand and clean fill. Much of the high-profile work currently going on in New York City, including subway construction and reconstruction, is using materials from Bronx County Recycling.
A Matter of Dirt
The materials that go in through the gates of Bronx County Recycling often arrive with a lot of dirt mixed in, which was sometimes ending up in the finished products. Since this was not the desired result, Cascino and Grottola turned to Lance Conley, Atomic Truck & Equipment, Fort Plain, N.Y., for a solution. Atomic Truck & Equipment is the New York state distributor for Construction Equipment Company (CEC).
Conley first got involved with Bronx County Recycling 15 years ago when he sold them a CEC 25 x 40 jaw crusher, which is still in use, and a CEC impact crusher, which is currently being rehabbed. Bronx County’s crushing equipment inventory also includes a CEC 32 x 54 jaw crusher with a quarry king pre scalper, a CEC 25 x 40 jaw crusher, a CEC 40 in. closed circuit cone crusher with a 6 x 20 screen, a CEC 133 x 115 impact plant, a CEC 6 x 16 Screen-It and numerous overland conveyors and stackers. Five loaders and three excavators, one with a hammer, for moving materials around the site, complete Bronx County’s inventory. The majority of the crushing equipment was manufactured by CEC and purchased through Atomic Truck & Equipment.
In order to develop a solution to Bronx County’s problem with dirt remaining in some of its end products, Conley worked closely with Cascino and Grottola, along with the engineering department at CEC. The end result of the collaboration was the concept of prescreening or “de-dirting” the mixed materials so that oversized materials that reach the jaw crusher for processing have already had the dirt and smaller aggregate materials removed. The prescreening process creates three materials: 5/8-inch minus fines, 3/4-inch clean stone and 1 3/4-inch clean stone. None of these materials see the crusher; only the oversized pieces are moved through the crusher spread.
According to Grottola, the results of setting up this process have far exceeded his expectations.
“Our primary objective was to improve the quality of the product that we were producing. The added bonus was a 100-percent increase in our production levels. The materials coming out of the crusher were definitely much cleaner and the pre-screening or ’de-dirting’ process gave us a wild increase in production levels. These increases in production levels are very important to us. By the nature of where we are located we are very limited in space to stockpile unprocessed material. Before pre-screening we were always very close to our stockpile limits, thus limiting our production potentials. These increases in production have put our stockpiling issues under control. Not only are we producing more product, but we also have been able to scale back production from six days a week to five days a week, while still experiencing an increase in sales. Because of our unique location in the heart of one of the largest cities in the world we were able to significantly increase our sales even in a down economy.”
The addition of a CEC 40 in. series slow-speed cone crusher to the crushing spread at Bronx County also has helped to increase production and create a cleaner product. The oversized material is now sent through a primary jaw crusher, a secondary jaw crusher and finally, the newly purchased cone crusher. A cone crusher squeezes rock until it pops. It frees the aggregate from its natural matrix versus secondary jaw crushers that demolishes the stone, which creates an unnatural break and produces a dirtier product. In fact, so clean is the product Bronx County can now produce that in some applications customers have requested that the aggregate be “dirtied up a little bit” because they have difficulty getting it to bind.
The use of a cone crusher in a recycling facility is unique because when material is brought in, the recycler has very little control over the content of the load and there is often non-aggregate material such as rebar, fabric, wood or plastic present. When non-aggregate material gets inside of a cone crusher it prevents the cone crusher from operating properly. The crusher will not be able to break the stone.
Bronx County Recycling has avoided this problem by visually inspecting every load of material that is brought to the site before it is accepted for recycling. If there is any non-aggregate material visible the load is rejected and sent to the picking station for removal of the material. In addition there is a magnet set up between the primary jaw and the secondary jaw, which removes non-aggregate materials that were missed during the visual inspection process. Between the second jaw and the cone there is another magnet and another picking station to remove any foreign material that was missed during the first two processes.
These processes, although seemingly time-consuming, have not only allowed the cone crusher to work properly to increase production and make a cleaner product, but also have lowered the operating cost of the crushing spread. Because cleaner materials are going in, wear and maintenance costs have been reduced significantly.
“Blow bars are being replaced far less frequently and since the system was started up several months ago the plant has not used a dime’s worth of wear steel,” according to Grottola.
Conley credited Grottola’s skill and experience with helping to find answers to challenges when the two men work together.
“Much of the reason that we can quickly work through any challenges for Bronx County Recycling that arise is the background and flexibility of Vincent Grottola, Bronx County Recycling superintendent. Vince has such a good understanding of the mechanical and engineering processes behind aggregate production that when a problem does arise he can typically work it out with me over the phone. Bronx County Recycling processes a very wide variety of different types of materials. Because of this product mix unique challenges at times do occur. At times it may take some input and advice from CEC in Oregon, but ultimately we have always been able to conquer any of the challenges that arise.” CEG