Stirred Bed Reactors (SBR)

Developed specifically to overcome the physical limitations of conventional fluidized beds and tubular reactors, InVerTec’s Stirred Bed Reactors (SBR) provide an engineered solution for the thermal conversion and chemical recycling of demanding feedstocks—particularly fiber-reinforced composite materials.

High-aspect-ratio additives, such as continuous glass and carbon fibers, typically agglomerate, cause entrainment bridging, or defluidize standard gas-solid beds. The SBR utilizes mechanical agitation combined with a dense, mobile solid heat carrier to ensure continuous, blockage-free operation under severe thermal conditions.

Key capabilities

• Blockage-free processing of fiber-reinforced composites and difficult solids
• Direct flash pyrolysis via agitated spherical heat-carrier media
• In-situ mechanical attrition and comminution of fibrous fillers
• Clean bottom solids discharge without off-gas line fouling
• Wear- and corrosion-resistant high-temperature agitator design
• Experimental validation from benchtop miniplants to pilot scale (TRL 3–6)

Technical Focus

The core of the SBR platform consists of an agitated bed of thermally and chemically resilient spherical particles (such as ceramic or metallic media) driven by a specialized internal stirrer system:

• Direct Flash Pyrolysis: Composite materials are continuously metered into the upper reactor zone. Upon intimate contact with the vigorously mixed, heated spherical media, the polymer matrix undergoes immediate flash thermal decomposition, minimizing secondary gas-phase degradation and maximizing valuable monomer/oil yields.
• In-Situ Mechanical Attrition (Milling): As fibers pass through the agitated spherical bed, the high shear and compressive forces exerted between the colliding media comminute and mill the fibrous fillers down into fine, non-fibrous particulate residues.
• Separation & Bottom Discharge: The finely ground inorganic fillers continuously migrate downward through the bed and exit via the bottom discharge system, enabling clean physical separation from the pyrolytic raw gas stream without risking system fouling or line clogging.

Achievements

• High-Durability Reactor & Agitator Design: Custom mechanical engineering with high-temperature alloy selection and wear-resistant coatings designed to withstand abrasive fillers and corrosive decomposition atmospheres.
• Integrated Peripheral Processing: Seamless coupling with high-torque dosing systems, inert gas locks, hot-gas cyclone filtration, multi-stage condensation units, and downstream off-gas treatment.
• Experimental Scale-Up & Validation: Testing facilities ranging from benchtop miniplants to pilot demonstration units (TRL 3–6), supported by comprehensive mass and energy balance evaluations and inline gas analytics (e.g., GC-FID/TCD).