Smithfield Peat Co. recycles with AirMax

SMITHFIELD, RI – Smithfield Peat Co. is a road and utility contractor and an organic and aggregate materials producer that provides services to real estate development affiliates and third parties.  In its early days, the company’s 81-acre headquarters contained a 17-acre peat bog, hence the name “Smithfield Peat” Co. They originally sold screened peat and loam fortified with peat, earning a reputation for producing highly organic soils. Since 1964, the company has been committed to the organic recycling of leaves, grass, brush, and stumps from its own projects. They also accept a high volume of inbound material from landscape customers who dumped yard waste free of charge for many years. Over the last five decades, they’ve grown from a family-owned peat bog into one of the leading organic materials producers of screened loam, compost, and mulch in Rhode Island and Southern New England.

The company continually adapts to the shifting organics market by embracing new technology. Jackson Despres, President of Smithfield Peat, has seen the family business go through many periods of expansion marked by investments in the latest equipment.

In 1995, with their supply of peat nearly depleted, and RIDEM about to adopt composting regulations, they officially entered the composting business to amend their screened loam with compost by purchasing a robust grinding system. 

“Prior to the grinder, we let the yard waste naturally decompose before screening,” Despres said. “When presenting our business plan, our bank expressed concerns about the availability of intended feed stock. We pointed to the pile of yard waste which had swelled to over 100,000 cubic yards, indicated that we were instituting a tipping fee, and the loan was approved. In 1995, we bought the second stationary plant manufactured by Continental Biomass Industries (CBI). Our rotor has the original main bearings with over 40,000 hours on it and it's still functioning virtually as well as the day we bought it.” 

Smithfield Peat’s compost production process includes multiple grinds of organic material formed into windrows. The windrow temperatures are carefully monitored and turned as needed to kill off weed seeds. This process makes the material ideal for garden compost. The decomposed plant material is finely screened to ¼ inch, setting Smithfield Peat’s compost apart from the competition and providing a nutrient rich product highly regarded by homeowners, landscape professionals, nurseries, and organic farmers.

“In the early 1970’s, we initially bought mulch wholesale and retailed it here in the yard,” Despres explained. “With the primary grinder in place, the installation of a secondary grinder, coloring machine, and extensive use of conveyors, the company could produce mulch in one pass. This gave us access to yet another market by eliminating the mulch wholesaler. Sheared stumps are fed into a disc screen, to remove fines, into a primary grinder, and then down to the final size through a secondary grinder and directly into a coloring machine, allowing us to manufacture what we sell.”

Logs and whole tree chips are loaded into a hopper between the primary and secondary grinders when the pre-screener isn’t needed.

Smithfield Peat Co purchased a jaw and cone crusher in 1996, allowing the company to expand into the aggregates business with crushed stone, processed gravel, and reprocessed asphalt and concrete. These materials would be recycled into reclaimed road base materials. Before long they offered compost, mulch, topsoil, and aggregates.  Since they manufacture a variety of what they sell, the company offers competitive pricing and exceptional service. They accept yard waste which they process into nutrient rich organic compost, and whole tree chips and brush that they process into premium landscape mulch. Smithfield Peat has truly evolved into a one stop shop.

However, Smithfield Peat’s success created one huge problem.

“Through our history we’ve accumulated a great deal of mixed waste (tailings) comprised of loam, wood, and stone,” Despres explained. “The pile accumulated to 100,000 cubic yards and occupied several acres of our property and virtually had no value. We couldn't even sell it for common fill because the wood would deteriorate and the ground would settle.”


Despite this, he saw a latent opportunity in the pile. Despres had long sought a solution for the 100,000 cubic yards of mixed waste. The organization’s commitment to processing material into valuable renewable resources demanded a solution for the pile, even if one didn’t exist yet. 

“I examined existing technologies available in the marketplace and challenged multiple manufacturers to come up with a machine that would effectively separate rock and wood,” Despres said.

Leveraging his close relationship with CBI--the company who manufactured and installed Smithfield Peat’s first two stationary grinding systems--Despres’ unique vision ultimately led to the release of the AirMax Material Density Separator.

The AirMax Material Density Separator is one of CBI’s latest material management solutions. Ideal for separating rock from wood and plastic, mulch cleanup, compost cleanup, C&D recycling, glass recycling, automotive fluff recycling, and a variety of other applications. From concept to completion, the machine was designed to solve Smithfield Peat’s 100,000 cubic yard waste problem.

The AirMax does everything a standard air knife does, in a self-contained, self-filtering package. Four electric motors total 42 HP to separate materials of different densities. Lighter material is blown clean off the stone and through the expansion chamber, while the heavier stone falls below to a conveyor belt. Two separate end products are produced. Seventy percent of the air is recirculated through the system for optimum efficiency and low energy costs. The AirMax can be adjusted for use with materials in different applications. 


The 100,000 cubic yard tailings pile of loam, wood, and stone is sent to a vibratory screen. Larger material is sent to a picking station where laborers manually pick the oversized wood while the stone is allowed to drop off the end of the conveyor. From there, undersized material goes to a trommel screen that separates the loam out. The trommel screen discharges a wood and stone mix into the AirMax.

"The AirMax is able to separate the wood and stone into two components so that everything is usable in the stream,” Despres said. “In my opinion, this has proved to be the best technology available in the marketplace, we’ve had great success with it separating the components.”

The AirMax creates new value in the otherwise useless pile of mixed tailings and opens up space in their yard now that material isn’t piling up. The end-products (loam, stone, and wood) are of superior quality.

“The stone is exceptionally clean and we’re able to send that to the crushing operation to make dimensional stone out of it,” Despres said. “The wood is either ground to make compost or mulch. In essence, we will turn 100,000 yards of waste material into finished, valuable product.”

Smithfield Peat prides itself on innovation. They pioneered organic recycling long before the advent of the green movement. True to their green values, they continue to find renewable uses for materials, including the mixed waste they put through the AirMax on a daily basis.

“It's taken a waste pile and allows us to take all of the components and make finished products out of waste,” Despres said. “It's extremely important that we do that from both a business standpoint and an environmental standpoint.”