Ansonia, Conn.-based compounding systems manufacturer Farrel Corp. is introducing developments in continuous mixing technology that make its machines more productive and provide incremental energy, maintenance and process efficiencies.
The Farrel-brand continuous mixer is a compounder that feeds to an extruder.
Recent updates include improved seal and venting designs, enhancements to the adjustable dam assemblies and new wear coatings for rotors and chamber barrels that provide additional abrasion resistance, according to Farrel Corp. President Paul Lloyd, who is also director of the Farrel Pomini business unit.
Farrel Pomini is a subsidiary of Harburg-Freudenberger Maschinenbau GmbH in Hamburg, Germany.
Farrel builds compounding systems for PVC, flooring, flame retardants and more. The unit also is active in petrochemical processing applications and will install a petrochemical line in Europe later this year, Lloyd said in an email.
Both the equipment production and research and development sides of Farrel have been busy, Lloyd added.
"The growth we are experiencing is being driven by environmental concerns and the certainty of greater regulations going forward. Those factors are creating the need for more sustainable materials," he said. "There has also been a significant increase in the home improvement industry due to the pandemic, and we are seeing growth in markets such as flooring, decking and roofing materials."
Farrel has been working on a lot of projects to overcome hurdles related to compounding both recycled materials, which are intrinsically contaminated and often complicated with different pigments and granule sizes, and biodegradable plastics, such as polyhydroxyalkanoates (PHA) and polylactic acid (PLA).
"We have seen approximately a 60 percent increase in recycled and biodegradable trials in our customer demonstration facilities in both the United States and United Kingdom," Lloyd said.
"With environmental concerns at the forefront, our traditional customers are pivoting to recycled feedstocks, particularly for compounders that operate in the building and construction, flooring and packaging industries. We are also seeing new customers that manufacture or compound biodegradables, including PHA and PLA. It's exciting to be involved with processing the newer materials within the circular economy," he said.
Continuous mixers generally have capacities of 6,000-40,000 kilograms per hour and are used for larger-scale compounding.
Farrel customers have been shipping their materials to the company's two demonstration facilities for trials conducted while they participate virtually.
"Fortunately for us, continuous mixing technology is inherently capable of processing recycled material well," Lloyd said. "It is adiabatic in nature and does not impart additional heat or energy into the compound, which is important to maintain the integrity of the polymer, including molecular weight, which is extremely important for processing bioplastics."
The recent advances made to Farrel continuous mixers offer compounders of recycled materials several advantages, Lloyd said. He pointed to the large single-entry feed port to handle irregularly sized feedstocks and large amounts of additives and fillers; nonintermeshing, counter rotating rotors and a large free volume mixing chamber that can tolerate the often abrasive nature of recycled materials; and "excellent" temperature control achieved, in part, by unique rotor geometry and process parameters like adjustable dams, orifice position and rotor cooling.
In addition to improving its equipment and components, Farrel Pomini invests in research to develop new applications for its continuous mixing technology.
"Of course, the current emphasis on recycled and biodegradable materials is driving this area of development and it is a dynamic and rapidly evolving landscape of materials and applications," Lloyd said.
Farrel Pomini participates in several partnerships with material producers and universities. The company has conducted joint research projects with NatureWorks LLC, Birla Carbon and Orion Engineered Carbons.
Also, Farrel has a partnership with University of Connecticut School of Engineering on a rotor coating development project and it supplied a CPeX-brand laboratory compact processor to UMass Lowell's plastics engineering laboratory for joint research on topics such as recycled and reground plastics processing, polymer degradation and biopolymer processing.