Plastics Department

Plastics in the Spotlight

Speakers at the Institute of Scrap Recycling Inc. (ISRI) 2009 Convention detailed the challenges associated with recycling plastics from electronics and industrial sources at a session titled "Spotlight on Industrial and E-Plastics."

According to session moderator Kim Holmes of 4\R Sustainability Inc., Portland, Ore., plastics account for 17 percent to 20 percent of electronics by weight, with 15 billion pounds of the material generated globally per year. Of these plastics, HIPS (high-impact polystyrene) makes up 56 percent, and ABS (acrylonitrile butadiene styrene) accounts for 44 percent, she noted.

Ron Sherga, principal of Sher-Results LLC, Arlington, Texas, said a decline in virgin capacity for benzene-based plastics, such as ABS, has led compounders and virgin producers to look at reclaimed ABS material.

Plastics that have been treated with flame retardants (FRs) are a challenge that can potentially limit the use of plastics that are reclaimed from electronics. Sherga said FRs could reduce the physical properties of the engineering resins used in electronics, making them difficult to reuse. However, they could be a plus if the final application required it, he said.

Chris Brough, vice president of engineering and product development for IntegriCo Composites, Temple, Texas, also noted that FRs affect mechanical properties, adding that impact modifiers are needed in IntegriCo’s composite rail tie manufacturing process to counter the effect of some additives.

Separating FR material from non-FR material can be costly, particularly if the material has been downsized. Sherga said larger pieces of plastic are easier to sort and to market, though the cost to transport the material would be higher because of the lack of density.

Using recovered plastics can save companies money by adding value to an application, he noted. "It’s not what you know but what you don’t know that produces the value."

While the IntegriCo process can use ASR (auto shredder residue), Brough said EPA regulations presented the biggest challenge in this area, as they call for the PCB content to be below 2 parts per million (PPM). "It’s very, very, very, very difficult to get an ASR stream with 2 PPM or less," he said.

The challenges associated with using plastics recovered from electronics in the company’s process include difficulty in distinguishing the multiple polymers and contamination from metal, ink and glass, Brough said.

When it comes to plastics recovered from post-consumer bottles, a recently released report predicts the capacity to recycle plastics and the demand for recycled material will grow to exceed the volume of plastics collected.

The report, titled "Plastic Bottle Recycling: A Global Strategic Business Report," from Global Industry Analysts Inc., San Jose, Calif., finds that as the volume of recycled bottles continues to surge, the rate of recycling remains steady, indicating a parallel surge in using plastic bottles for a wider range of products.

Details about the report are available at www.strategyr.com/Plastic_Bottle_Recycling_Market_Report.asp.