|dc.description.abstract||This thesis used way of experiment to studied pelleting property of rice straw with additive of rice bran and rice husk. Furthermore, the Taguchi method was used in order to found optimal parameters of pelleting experiments. The experiment was divided into two parts, semi-automation design of pelleting machine and research of pelleting properties for rice straw with additive respectively.
In design of pelleting machine, the RDF pellet can be produced from one to 5 for new design of pelleting mold. The jig of fastener ring and mechanism of bottom mold were also designed.
The first Taguchi method was used in this thesis that found optimal parameters in pelleting experiments of rice straw with additive of rice bran and rice shell. The optimal parameters were amount of additive 0.05 g, moisture content of rice straw 8 %, moisture content of rice bran 8 %, moisture content of rice shell 4 % and pelleting pressure 50 kg/cm2.The verifying experiments were undertaken according to results of first Taguchi method. The optimal parameters of additive of rice bran and rice shell were found in verifying experiments. In part of rice bran, the pelleting pressure 30 kg/cm2, 35 kg/cm2 and 50 kg/cm2, amount of additive 0.410 g (20 %), 0.512 g (25 %) and 0.615 g (30 %). In part of rice husk, the pelleting pressure 40 kg/cm2, 45 kg/cm2 and 50 kg/cm2, amount of additive 0.05 g (2.5 %), 0.102 g (5 %) and 0.205 g (10 %), both moisture content of additive 4 %, 6 % and 8 % have optimal density for RDF pellets of rice straw with additive.
The second Taguchi method was used from results of verifying experiment. The optimal parameters of rice bran included amount of rice bran 0.615 g, moisture content of rice straw and rice bran 6 %, pelleting pressure 50 kg/cm2. In part of rice husk, the conditions of amount 0.205 g, moisture content of rice husk and rice bran 8 %, pelleting pressure 35 kg/cm2 have optimal pelleting properties and density of RDF pellets increased in additive of rice bran, there is not the additive of rice husk .All have the tendency to raised to hardness and heat value under adding the additive of rice bran, but the rice husk has not obviously risen.