Vacuum Conveying and Dedusting for Polycarbonate Recycling – Highline Polycarbonate

The Challenge: Removing Dust and Static from Abrasive Polycarbonate Regrind

Highline Polycarbonate produces specialty polycarbonate sheet for high-performance applications requiring exceptional clarity, including laser-blocking, military, and other custom uses.

To support this standard, the company built a dedicated recycling facility in New Jersey to take back used polycarbonate sheet from customers, process it down to regrind, and convert it back into new optical-grade sheet. The output can match, and in some cases exceed, the quality achievable with virgin resin.

To make that possible, Highline needed a system that could convey regrind from the grinder, remove dust and static, and package it cleanly without contaminating the output.

The final system had to address several specific challenges:

• Polycarbonate regrind is abrasive and static-prone, requiring a system configured specifically for the material.
• Any residual dust or fines would compromise optical clarity and impact resistance in the finished sheet.
• All captured dust had to remain fully contained to meet state environmental requirements.

Highline’s new facility is dedicated exclusively to clear polycarbonate, with every piece of equipment and every process step designed around material purity.

The Facts: Material Specifications and System Requirements

Material Specifications:

• Material: Post-consumer polycarbonate sheet sourced from global suppliers
• Material characteristics: Abrasive and static-prone polycarbonate
• Output requirement: Optical-grade quality suitable for re-use
• End uses: High-performance applications including laser-blocking, military, and other custom uses requiring exceptional clarity

System Requirements:

• Turn-key solution covering conveying, dedusting, and bulk bag filling
• Integration with existing granulator, operated from a single control panel
• Fully contained process with no dust released into the facility
• Air filtration to meet state environmental requirements
• Compact design to accommodate limited ceiling height in available facilities

The Solution: A Fully Contained Vacuum Conveying and Dedusting System

Highline needed a complete system to convey polycarbonate regrind directly from the granulator, remove all dust and fine particles, and deposit clean material into bulk bags without releasing processed dust into the facility. Kongskilde’s certified installation team designed, supplied, and installed the system.

System Components:

1. AirWash – A vacuum-based conveying and dedusting unit that pulls regrind directly from the grinder under negative pressure and removes dust and fines through a two-stage cleaning process.
2. Heavy-Duty AK Rotary Air Lock Valves – Specified for polycarbonate’s abrasive characteristics to ensure long service life throughout the system.
3. Anti-Static Unit – Neutralizes static charge in the regrind as it moves through the system, preventing fine particles from building up on pipe walls and surfaces.
4. PolyVac – Receives clean regrind and fills Super Sack bulk bags on a pallet-mounted weighing scale, allowing operators to monitor fill weight in real time.
5. K-Series Filter – Captures dust from both the AirWash and PolyVac 50 at 99% efficiency at 0.3 microns, returning filtered air to the facility interior.

How the System Works

• Regrind is drawn from the granulator under vacuum into the AirWash.
• A vortex separates fine dust particles while heavier regrind falls through.
• The anti-static unit deionizes the polycarbonate dust as the system removes it.
• Clean regrind drops into the PolyVac, which discharges it into bulk bags.
• The K-750 filter then captures all remaining dust and fines, returns purified air to the facility, and drops captured fines into sealed barrels.

The result is a fully contained process that takes regrind from the granulator to the bulk bag without releasing dust into the facility or compromising the quality of the output.

Advantages & Benefits: Consistent Optical-Grade Regrind and a Cleaner Facility

Since installing the Kongskilde system, Highline has seen reliable performance and measurable improvements in day-to-day operations.

High-purity regrind

The AirWash removes dust and fine particles from ground polycarbonate, producing regrind that consistently meets strict clarity and performance requirements with no adjustments required since commissioning.

Clean facility

Processed dust never reaches the facility environment. Sealed barrels capture all fines and route them to third-party processors instead of landfill.

Simple operation

The system is interlocked with the granulator control panel, so the granulator cannot run without the conveying system already active.

Easy integration

Kongskilde coordinated directly with the granulator manufacturer on all electrical and mechanical connections, ensuring the system worked correctly from day one.

Fast commissioning

Pre-installation coordination with the granulator manufacturer meant the system arrived ready, and the team completed commissioning in a single day.

Capacity for growth

Because the system capacity exceeds current throughput needs, giving Highline room to grow without modifying the system.