Strathclyde Fluidised Bed
Composite recycling
Fluidised Bed
Fluidised bed reactors have been used in many different applications. Fluidisation is a state reached when conditions within the reactor cause solid particles to behave as a liquid.
When applied to composite recycling, a sand bed is fluidised and heated. Composite material is then fed into the fluidised sand. The heated sand decomposes the matrix of the composite material by means of thermal degradation and erosion. This decomposition releases fibres from the composite materials which can then be collected and reused.
To achieve recycling of composite materials a bespoke fluidised bed rig was designed. The main parts of the design were the airflow and heating system, the reactor bed and the separation system.
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Fluidisation is achieved under certain flow conditions within the fluidised bed reactor. Gas (airflow) is forced into the reactor and through the fluidisation plate, which supports the sand bed. As the flow velocity is increased the weight of the material is balanced by the upwards force applied by the airflow. When these forces are equal the particles of sand achieve neutral buoyancy. Further increasing the velocity of the flow causes the sand bed to act as a fluid with high levels of mixing and uniform temperature gradients when heated.
Fluidisation Process
 Diagram of fluidised bed produced |
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