This issue is of great practical significance. The core of carbon fiber solid waste recycling is to achieve fiber reuse or energy recovery through physical or chemical methods. A mature technology path has now been formed.  Core recycling technology Physical recycling method: dismantle solid waste through mechanical crushing, grinding and other means to separate chopped carbon fibers. The process is simple and low-cost, and the strength retention rate of recycled fiber is about 50%-80%. It is suitable for low value-added scenarios such as composite fillers.  Chemical recycling method: Use high-temperature pyrolysis, solvent degradation and other reactions to remove the resin matrix. It can recycle longer fibers and achieve a strength retention rate of more than 80%. It can be used in mid- to high-end composite materials, but equipment and operating costs are high.  Energy recovery method: incinerate mixed solid waste that is difficult to separate to generate electricity and recover heat energy. The treatment efficiency is high, but fiber cannot be recovered and is only suitable for low-value solid waste.  Key recycling challenges: The cost of recycling is higher than that of virgin carbon fiber, and the market competitiveness is insufficient.  The length and strength of recycled fibers are uneven, making it difficult to meet the needs of high-end products.  The recycling system is imperfect and the solid waste collection, classification and transportation links are not smoothly connected.  Application direction Low value-added areas: concrete additives, friction materials, sound insulation and heat insulation materials.  Medium value-added areas: automotive interior parts, core materials for wind turbine blades, and sporting goods accessories.  Energy recovery: used as industrial boiler fuel to replace fossil energy.