Hemp decortication by a mastication process

Abstract

The goal of this Master’s Thesis research was to design, fabricate and test a mechanical decortication system for unretted bast fiber plant stalks with a particular focus on hemp. To preserve hemp fiber quality and maximize the hurd removal, a new decortication concept based on the teeth structure and chewing process (mastication) of herbivores (e.g., elephant) has been designed and developed as an improvement of current methods. With this new concept, a set of tools crushes hemp stalks under control conditions to induce effective fiber/hurd detachment during crushing cycles. Compression tests were performed to investigate the deformation behavior and corresponding acoustic response of hemp stalks during mastication. An apparatus was designed, fabricated and tested to run experiments that demonstrate the process and assess parameter sensitivities. Finally, the effect of process parameters on decortication quality was investigated, and parameter combinations that yielded the best result were identified.