Process Streamlining – Construction & Demolition Recycling

For years, Long Island, New York has been plagued by pollution from toxic spills and the mismanagement of industrial waste. The pollution had the potential to negatively affect the island’s groundwater and drinking water via three major source aquifers near the Earth’s surface.

Posillico Materials LLC, Farmingdale, New York, recognized the need to address growing concerns over Long Island’s soil pollution and landfill capacity, and in 2019 the company opened a washing plant on the island to help clean it. Recently, the company invested in a Hydro:Tip wet processor from CDE, based in Northern Ireland, to expand its cleaning capabilities.

The company’s dedication to cleaning up the island, its use of a washing plant and its efforts to improve its operations earned the company recognition earlier this year when Posillico was named 2022 C&D recycler of the year by the Construction & Demolition Recycling Association (CDRA), Chicago.

Announcing the price, CDRA said the addition of the washing plant showed Posillico’s willingness to take a risk to recover more material and added that the company’s research and development department was actively seeking more of materials to be recycled.

“We are always looking for opportunities that align with our strategic goals and to bring innovative solutions to the industry the way we know how to do it,” says Robert Tassey, Wash Plant Manager for the Posillico facility. in Farmingdale.

Founded in 1946, Posillico is a fourth-generation family business that provides various integrated services, including heavy civil works for the public and private sectors and environmental remediation, paving, drilling and construction contracts. public services. The company receives material from construction sites and sumps along New York’s freeways.

Construction of the wash plant coincided with a 2018 joint investigation between the New York District Attorney’s Office, the New York State Department of Environmental Conservation (DEC), and the Department of Suffolk County police in a conspiracy to illegally dump solid waste in various locations across Long Island. The month-long investigation, known as “Operation Pay Dirt”, resulted in a 130-count indictment against 30 people and nine companies for illegal solid waste disposal at 24 sites, including 19 residential, four commercial and one school, according to Suffolk. County.

Harmful substances found in the waste included arsenic, beryllium, cadmium, cobalt, chromium, copper, lead, nickel, zinc and mercury.

A meticulous process

Posillico’s operations include five permanent concrete recycling operations that each have their own crushing systems and supply recycled aggregate for various markets, two hot mix asphalt, or HMA, plants that use recycled asphalt pavements in their mixtures. The company’s Farmingdale wash plant accepts excavation waste, uncontaminated material, contaminated fill, vacuum truck waste, dredged material and mixed loads.

CDE’s Hydro:Tip is designed so operators can process wet materials including mud, fluids and clay in a cost-effective and responsible manner, facilitating the recovery of sand and aggregates that can be resold to generate springs. additional income. The Hydro:Tip can process 20 tonnes of material per hour and allows hydro-excavation fleets to locate closer to extraction sources to reduce haul time, costs and fuel emissions, explains the CDE.

Before the company invested in the system, Tassey says pretreating and stabilizing a hydro-excavated load took up to 45 minutes and was weather dependent. The company can now process different amounts of material per load through the Hydro:Tip in around 15 minutes.

The process begins with a conveyor dumping the material into what Tassey describes as a giant hopper with multiple spray nozzles and jets that liquefy the material into a homogeneous slurry. The material then passes through a sizing screen which passes liquids, mud and sand-sized particles using rinse bars. The remaining material, including brick, gravel and asphalt, is rinsed off with spray nozzles and stored.

The material filtered out of the sizing screen is collected in a sump which feeds it through hydrocyclones which further separate the sand from the mud and liquid. Tassey says the process also removes chemical contamination, such as petroleum.

“With the addition of the Hydro:Tip, we are now able to dewater this sludge, separate the liquid from the solids, treat the water directly in our washing plant, and then treat the solid material the same way we would with our other infill,” Tassey said. “It’s the cleanest, safest, most effective and efficient way to handle hydro-excavation waste on Long Island. “

The sand is then dumped onto a dewatering screen, equipment that vibrates the remaining water out of the sand. The result is washed and deslimed sand. The rejected mud and water are placed in a tank which Posillico then pumps to its on-site water treatment plant to clean and polish the water.

“The Hydro:Tip is an extension of our full-scale washdown facility,” Tassey says. “It’s specifically designed to take a large volume of supersaturated material and process it in a short time.”

Tassey says the equipment removes various contaminants to recover up to 85% of hydrovac materials. The remaining 15% of the material, called the filter cake, tends to retain organic contaminants and is removed out of state.

Since opening, Tassey says the system handles about 75 to 100 loads per month of different types of solids and liquids. However, demand for the company’s services has increased due to reduced downtime between charges.

“We’re able to handle four times more loads with the Hydro:Tip than before,” says Tassey. “The hardest part of operating this equipment is meeting the demand we have now after opening this part of the plant.”

The company’s C33 concrete sand is used by the concrete and asphalt market. Tassey says the gravel produced by Posillico comes in three different sizes and is used in a variety of applications. The company produces 3/8 inch gravel, 3/4 inch stone and a wide range from 2 inches to 4 inches in thickness. Tassey says 3/8-inch and 3/4-inch concrete are used in commercial construction as a raw material and as fill for tanks and retaining walls. Washed oversize material is used for tracking pads and drainage material.

While the operation of the Hydro:Tip equipment went smoothly, Tassey says the biggest hurdle was the logistics of offloading materials to the small site. Posillico’s Farmingdale site is built on 4 acres and the Hydro:Tip equipment occupies a 50 foot by 50 foot portion of the site. The remaining space is occupied by the main washing plant, product stocks and traffic lanes for customer trucks. The company had to develop a new method for vehicles to enter the facility to dump their material, including building the Hydro:Tip into an existing retaining wall where vacuum trucks can now dump.

Equipment operating costs include electricity, an operator and maintenance. Ms. Tassey explains that because the Hydro:Tip is a batch process, operating costs are low since it only consumes energy when it is running.

The company says another benefit of the Hydro:Tip is that it has created more space in the installation. Prior to using the new equipment, the company used to stabilize materials in berms until they could be transported to the washing plant. This prevented trucks from entering because there were capacity issues. The new equipment eliminates this problem by immediately processing the material and sending what remains to the washing plant.

Overall, the Hydro:Tip has improved the quality of service and safety for the business, as the equipment does not require the driver to enter the berm to clear the back of the truck in order to sure the material got in there, Tassey says.

“Our company’s safety culture is really paramount in everything we do,” he adds. “We really didn’t realize how risky and dangerous the old way of unloading trucks was. [into a berm] until we start looking for ways to eliminate this bottleneck in our process. »

Previously, Tassey noted the importance of Posillico’s processing facilities and equipment due to New York’s growing population and what he called an aging infrastructure. “There are going to be a ton of materials to deal with, and they need to be dealt with responsibly and efficiently. The way to do that is to recycle it in a factory like ours.