The present study evaluated the hydrolysis of rice husk, by means of alkaline peroxide, acid peroxide and silicate peroxide pretreatment, followed by enzymatic hydrolysis using cellulases, with a high level of β-glucosidases and hemicellulases. Pretreatments were performed by varying the concentrations of the alkaline medium (0, 2, 4 and 6 % p/v), acid (0, 5, 10 and 15 % v/v) and silicates (0, 5, 10 and 15 % v/v) in varying concentrations of peroxide (0, 5, 10 and 15 % v/v). Enzymatic hydrolysis was performed at 50 °C, pH 5, 72 h, 0.3 mL of enzyme per g of husk, with a load of 5 % w/v. The morphological characterization of the surface of the rice husk by means of the SEM presented a greater transformation in alkaline-peroxide medium. The concentration of reducing sugars after the alkaline peroxide pretreatment (6 % KOH – 15 % H2 O2 , pH 11, 70 °C, 3 h and with a load 10 % p/v) and t...

In the present study, the stabilization of horse manure (mixture of rice husk, manure and horse urine) was evaluated through an aerobic process similar to composting. The stabilization process was evaluated in two piles of horse manure for 16 weeks, taking samples every week. A decrease in temperature from 66,7 to 41,0 °C, the reduction of the density from 394,0 to 370,4 kg/m3, the reduction of the water retention capacity from 220,7 to 125,6% and the reduction of the respiratory activity of 9.8 to less than 2 mgO2/g ms/d, were indicators of the stabilization of the horse manure, the easily degradable material of manure and urine were removed by aerobic degradation and washed with irrigation, leaving only the rice husk with a minimum fraction of other materials. On the other hand, the increase in total nitrogen and a decrease in the C/N ratio at the end of the week 16 were indicative of...