Superfine grinding of steam-exploded rice straw and its enzymatic hydrolysis

The combination of low severity steam explosion and superfine grinding has been studied with respect to side products generation and enzymatic hydrolysis efficiency. Chemical compositions, fiber characteristics and composed cells contents in the superfine ground product and the ground residue particles produced by superfine grinding were also studied. At the determined parameters using FJM-200 fluidized bed opposed jet mill, 78% superfine ground steam-exploded rice straw (SERS) products with the mean fiber length of 60 μm were obtained, the particles yield was 179% higher than that from the native rice straw (RS). Enzymatic hydrolysis, chemical composition, fiber characteristics and composed cells proportion of the superfine ground SERS product and the ground residue all show great differences. The difference in enzymatic hydrolysis and structural properties indicates that superfine grinding is a good way to fractionate SERS into easily bio-converted part and difficultly hydrolysed part.