Economic and energy benefit of a method for treating the vapors coming from the recycling of carbon fiber waste by pyrolysis

Abstract

The growing utilization of carbon fiber reinforced polymers (CFRP) in industry involves the generation of high quantities of this kind of waste. This tendency has fomented the investigation of different alternatives to recycle CFRP waste with the aim of reclaiming the carbon fibers, a material with high specific economic value. Among the alternatives, pyrolysis is the only one runnig at commercial scale nowadays. This process consists on heating the waste in an inert or oxygen-poor atmosphere, which causes the decomposition of the polymeric resin of the material and consequently the reclamation of the carbon fibers. The resin decomposes into organic vapors, which are normally incinerated and released to the atmosphere. The objective of this paper is to present the economic and energy benefit of a method for treating the vapors coming from the resin decomposition, through which high value chemicals can be obtained, avoiding the vapors incineration and emission. By means of this recently patented method a gas fraction with a higher energetic content than that of the vapors without treatment can be obtained. Besides, this gaseous fraction contains high quantities of hydrogen, which could be separated and sold. The commercialization of this hydrogen could increase 6 times the economic value of the gaseous fraction compared to the gas fraction without treatment.