Avangard Innovative LP has taken a bold step to address the problem of odor in resin pellets made from recycled LDPE film by installing two new turnkey systems, purchased from Starlinger, at its Houston headquarters.
"To my knowledge, this is the first U.S.-based firm to operate a fully integrated turnkey solution to remove odors from recycled products," said Alan DiUmberto, sales manager, recycling division, American Starlinger-Sahm.
Avangard installed and started up the first Starlinger recoSTAR dynamic recycling line in December. "We will be considering using this technology for future projects, as demand and our supply of the right material mix dictate," said Jon Stephens, COO for Avangard. At press time, Stephens said the company was on schedule to have its second Starlinger line running by mid-February.
Avangard invested in Starlinger's odor-reduction technology because of issues it had processing post-consumer film, Stephens said. Paper labels and other plastics are the primary contaminants the company encounters in what is otherwise relatively clean material.
"When we process polyethylene film with labels in a dry line and use filtration to clean up the material instead of water, the major complaint from customers was the smell," he said. "The odor-reduction technology addresses this issue and greatly reduces the residual amount of smell on the pellets."
After spending more than five years in development, Starlinger introduced its odor-reduction technology at the K show in 2016.
The company describes the process in this way: First, the material enters the Smart Feeder, where it is prepared and homogenized by a bladed rotating disc while it is flushed with air warmed by radiant heat from the extruder. The material feeds into a Starlinger extruder, then the melt passes through a cascade filtration system with two melt filters. The first is a coarse filter that removes larger contaminants, followed by a filter that removes smaller particles.
The melt enters a Starlinger recoSTAR dynamic 165 C-Vac degassing module, which increases the melt surface area by 300 percent, and then exposes the material to high vacuum, efficiently and permanently extracting persistent odors, according to the company.
The melt then enters a water-ring pelletizing system. The pellets are conveyed to the Smell Extraction Unit (SEU), a tall, vertical tower, for the final step in the process. This technology is based on a modified PET solid-state polymerization (SSP) process that uses time, heat and pressure. For proprietary reasons, Stephens declined to give details about how the equipment has been customized for his company's specific application.
Stephens said Avangard's experience with Starlinger's odor-reduction system has gone smoothly.
"It is going as expected — or I would say better than expected — and we have made the necessary adjustments to our process to get to running the right rate and quality our customers demand," Stephens said.
Avangard is on track to hit its Phase 1 production goals, Stephens said. Once the company finishes the process of staffing up and running a 24/7 operation, he expects to meet the target of about 2 million pounds of recycled LDPE pellets per month, increasing to the plant's total production capacity of 4 million pounds per month once both lines are running 24/7.
"We feel the startup went very well and have been very pleased with the Starlinger support. We have been selling our pellets and finalizing trials with customers for approvals and have had great success already," Stephens said.
Starlinger said the process removes residual chemicals from food, cosmetics or detergents and also residues from monomers, oxidation, hydrolysis and volatile organic compounds. Odors can result from both chemical compounds in the material and compounds created in the recycling process itself.
The technology could create commercial markets for materials such as fuel tank recyclate, that didn't exist before because of the odor issue.
Starlinger points to other benefits of its odor-reduction system, including customized design, permanent smell improvement without additives, energy efficiency, extensive automation and superior resin quality.
Allan Gerlat, correspondent
For more information
Avangard Innovative LP,Houston, 281-582-0700, www.avaicg.com
American Starlinger-Sahm Inc.,Fountain Inn, S.C., 864-297-1900, www.starlingersahm.com
