Pelletron's pneumatic conveying and dust removal systems selected by NatureWorks
Pelletron is responsible for designing and supplying the pneumatic transfer systems from pelletizing to storage and packaging. The pneumatic conveying method applied is Pelletron's positive pressure Strandphase® technology, the most gentle and efficient system for PLA pellet handling. However, even the most gentle conveying process creates some fine dust, so NatureWorks will utilize Pelletron's patented DeDuster® equipment in critical locations of their process to keep the pellets clean, with fine dust content less than 50 parts per million.
In addition to standard equipment drawings, the design scope for Pelletron includes detailed process and instrumentation diagrams ("P&IDs") and 3D modeling of the pipe routing throughout the NatureWorks plant. Pelletron will produce these documents in coordination with Jacobs, the selected engineering contractor for the project.
All critical components such as rotary valves and diverter valves are equipped with instrumentation like speed switches, pressure transmitters, and level and position switches for constant feedback to the control system resulting in efficient operation and minimal downtime.
The selected rotary valves, Pelletron's GRM medium pressure model, have patented anti-shear features built into the housing to minimize pellet cutting. The valves also feature expanded rotor tips to reduce leakage through the valves, increasing the system's efficiency.
The diverter valves for the Thailand plant are Pelletron's PDV model, equipped with positive, self-adjusting seals at each port. PDV valves are engineered for zero leakage and are suitable for handling powders and pellets. The valve's end stops are built into the housing instead of the actuator so the actuator can be replaced without removing the valve from the conveying pipe, a significant time-saver for maintenance.
Fines content is a consideration for buyers of PLA resin, so Pelletron applied their low profile, high-performance XP Series DeDuster® after pelletizing and again just before packaging. The DeDuster® systems will remove fine dust in addition to coarse dust and streamers if present.
NatureWorks's parent companies, Cargill and GC, provided final approval for the $600 million investment in August 2021. The new, fully integrated plant located in the Nahkhon Sawan Biocomplex in Thailand will produce 75,000 metric tons of polymer per year. It is the second Ingeo PLA manufacturing location in the world. Its first was built in Blair, Nebraska, in 2002 and expanded in 2013 to produce 150,000 metric tons per year.
The expanded global production of Ingeo biopolymers will support growth in markets that demand sustainable, low carbon materials with high-performance attributes, including 3D printing, hygiene products, compostable coffee capsules, tea bags, flexible packaging, and food utensils.