Method and apparatus for explosively defibrating cellulosic fiber

Claim 1

In a process for explosively defibrating cellulosic fibre from plant material wherein the plant material is subjected to a high pressure environment followed by rapid transfer to a lower pressure environment, the improvement comprising passing the material from the high to the low pressure environment by way of a discharge nozzle across which a plurality of bars spanning diametrically across the nozzle having rounded leading edges facing in the direction of flow are arranged in such a manner as to cause the plant material passing therethrough to be folded over, successive bars thereby subjecting the folded plant material to shear and tensile forces generated by the concomitant passage of highly turbulent fluids causing the material to be successively pulled apart into individual fibres and fibre bundles wherein said bars are disposed at varying angles relative to each other along the longitudinal axis of the nozzle and the minimum number of bars and their arrangement in the nozzle is such that when the nozzle is viewed in the direction of passage of the plant material no clear passage exists in the nozzle through which a fragment of the plant material may traverse without being folded over a bar.