Wet, sticky, and contaminated material is one of the biggest challenges recycling plants face when it comes to screening. High moisture levels, fine particles, and residual contaminants can quickly clog conventional screens, causing blinding, reduced throughput, and frequent downtime for manual cleaning.
For recycling operations handling difficult feedstocks, the BIVITEC® screen’s flip-flow technology offers a proven solution. BIVITEC screens prevent blinding by continuously flexing the screening surface, keeping material moving and apertures clear — even in the most challenging recycling environments.
The Screening Challenges of Wet, Fine, and Contaminated Material
Recycling plants often process material streams that contain a mix of moisture, fines, and contaminants. Each of these factors presents its own challenges, but when combined, they significantly increase the risk of blinding and reduced screening performance.
Learn how to minimize blinding.
High-Moisture Content
Wet material tends to stick together, forming clumps that resist separation. It also adheres to screen surfaces, coating apertures and preventing material from passing through.
Common sources of moisture include rain exposure, wash water, organics, and residual liquids in mixed recycling streams. As moisture levels increase, screens require more frequent cleaning and experience reduced throughput.
Fines and Small Particles
Fines — such as dirt, dust, sand, glass fragments, and other small particles — can easily lodge in screen openings. When fines are present in large quantities, they pack tightly into apertures, especially when combined with moisture.
Instead of passing through the screen, fines can form a dense layer on the surface, blocking separation and forcing oversized material to carry fines downstream. This leads to lower product purity and inefficiencies throughout the plant.
Contaminants and Sticky Materials
Contaminants (like clay, soil, organics, food residue, plastics, and other adhesive materials) further complicate screening. These materials tend to cling to both the screen media and other particles, accelerating buildup on the screening surface. Sticky contaminants increase wear, reduce open area, and often require manual intervention to keep screens operational.
Learn how MRFs can reduce recycling contamination.
Why Conventional Screens often Fail
Vibratory Screens
Vibratory screens rely on vibration to stratify material and move it across a rigid screening surface. While effective for dry material, this approach struggles with wet or sticky feedstocks.
Moist material tends to adhere to the screen deck, allowing fines to pack into apertures and cause blinding. As buildup increases, the screen’s open area is reduced, leading to lower throughput and poor separation. Operators are often forced to stop production to manually troubleshoot common vibrating screen problems.
Trommels
Trommel screens use a rotating cylindrical drum to separate material by size. In wet or contaminated conditions, material can stick to the inside of the drum. Fines and sticky contaminants coat the screen surface instead of passing through, reducing screening efficiency and capacity.
Trommels also tend to struggle with high moisture content because material rolls rather than separates, allowing fines to remain trapped in the oversized fraction.
Star and Roller Screens
Star and roller screens use rotating elements to move material forward while allowing smaller particles to fall through. These systems can be effective for certain applications, but they are highly sensitive to moisture and contamination.
Sticky materials can wrap around stars or rollers, causing buildup, reduced movement, and increased wear. Fine material can accumulate between components, leading to clogging and frequent maintenance. In severe conditions, these screens may require regular shutdowns to remove wrapped material.
How the BIVITEC Flip-Flow Screen Prevents Blinding
The BIVITEC® flip-flow screen is specifically engineered to handle wet, sticky, and contaminated materials that cause conventional screens to blind.
Continuous Flexing Keeps Apertures Open
At the core of the BIVITEC design is a dynamically flexing screening surface. The screen media rapidly stretches and relaxes during operation, creating a flipping action that prevents material from settling into the apertures. This continuous flexing breaks the bond between sticky material and the screen surface, allowing fines to pass through rather than build up.
Material Is Thrown, Not Dragged
Unlike traditional screens that drag material across the deck, the flip-flow motion of a BIVITEC propels material upward and forward. This action minimizes surface contact time, reducing the opportunity for wet fines or contaminants to adhere to the screen. As material is repeatedly lifted and released, blinding is actively prevented rather than managed after it occurs.
Consistent Throughput and Uptime
By preventing blinding at the source, BIVITEC flip-flow screens allow recycling plants to operate at higher throughput with fewer interruptions. Operators benefit from:
- Reduced screen cleaning and maintenance
- More consistent separation results
- Improved uptime in challenging conditions
In recycling operations where moisture, fines, and contamination are unavoidable, the BIVITEC flip-flow screen provides a proven, purpose-built solution for keeping screens open and material moving. Contact AEI Screens today to find out how the BIVITEC can benefit your recycling plant.
