PPRC 2016: Addressing contamination at the MRF

Processors of residential material have more challenges in this area than some processors of IC&I material.

October 19, 2016

The current downturn in recycled commodities markets has put pressure on material recovery facility (MRF) operators. To ensure they get the highest value for the commodities they are preparing, MRF operators must prepare material to their consuming customers’ specifications. However, increasing levels of contamination are making this a more challenging task, according to Stacy Katz, manager of materials management and quality for Houston-based Waste Management (WM.)   

Katz, who spoke at the 2016 Paper & Plastics Recycling Conference session You Can’t Fix What You Don’t Measure, said MRFs are essentially manufacturing facilities. However, unlike other manufacturers, they are being asked to clean up contaminated material from their suppliers. This comes at the expense of MRF operators, with WM’s costs having increased by 20 percent in the last two years as a result of contamination in incoming material streams, she said.

Auditing of incoming material streams is an important tool for helping to address this issue, Katz said. It allows WM to see if the composition of incoming material aligns with its contracts, how the composition of the material stream might be changing and the effect that will have on the company’s equipment performance or requirements.

Katz said visual audits can be misleading and unreliable. Instead, WM takes statistically valid samples of incoming material. The company has found 16 percent contamination on average, however it has been as high as 50 percent in some cases, she said.

“MRFs are not designed to separate contamination but to sort recyclables,” Katz said.

In addition to auditing its inbound material streams, WM audits its outbound streams in an effort to optimize performance and extract more value from the stream, to ensure it is meeting the quality standards of its consuming customers, to determine ways to reduce contamination and minimize risk and to ascertain if its manual and mechanical processes are working correctly, Katz said.

With 9,800 recycling programs and the variety seen in new packaging materials, she said, “There is a lot of consumer confusion.” Katz added that municipalities have placed a “big push on diversion, but there is little focus on what is actually being collected.”

Single-stream recycling and the large carts used in these programs have helped to increase contamination, she said. This growth in contamination is reducing the viability of recycling long-term, Katz said, and is driving up recycling costs.

At the MRF, WM has had to add sorters to its presort lines to address contamination, Katz said. They remove film, which can jam equipment and reduce the effectiveness of screens, and other contaminants.

Katz said that for recycling to be sustainable, quality must be prioritized over quantity.

To address contamination, she said WM is employing different strategies, including tagging containers that contain contamination, outreach efforts, contract enforcement and penalties, and tracking their success.

“We can achieve a substantial reduction in contamination—about 50 percent—with direct outreach, but there is a cost,” Katz noted in her presentation.

She added that its cost-prohibitive for WM to clean up the contamination it finds in incoming loads unless the contract has related stipulations. “Our contracts need to protect the viability of the recycling industry,” Katz said. “Recycling contracts need to have contamination limits with funded education and enforcement programs with clear accountability.”

Cascades Recovery Director of Sustainable Materials Management Bruce Westaway, who also spoke during the session, was in a much better position to avoid contaminated material from customers. Cascades largely serves the industrial, commercial and institutional (IC&I) segment of the industry, setting up customized diversion programs.

Auditing is still an important component of Cascades Recovery's programs, however, that auditing occurs at the client's facility with an analysis of the waste stream prior to establishing a diversion program. Once the company knows the materials its client is generating, Cascades Recovery sets up customized programs that separate recyclables at the source.

“Source separation is the way to get clean material,” Westaway said. “Clean material costs less to prepare and is a higher-value product.

“Single-stream limits your options,” he continued, adding that it increases contamination and costs.

Westaway said that for companies handling IC&I accounts, source separation is a “simple solution that allows flexibility of materials with the lowest investment to process materials.”

The 2016 Paper & Plastics Recycling Conference is Oct. 19-21 in Chicago at the Marriott Chicago Downtown Magnificent Mile.