| The pre-pressing and solvent-extraction process is the major application in the processing of camellia seed. The traditional technology has the high energy consumption and high refining loss under hot pressing and chemical refining, which make the oil quality low. The technologies of low-temperature press and physical adsorption refining have the advantages of high product quality, low energy consumption and refining loss, which have become ones of the hot spots in the field of oil processing in recent years.We designed and developed the peeling machine of green camellia fruit and the dehuller of camellia seed under the aiming at the key technical problems existing in the processing technology of the camellia seed. We also study the low- temperature presser for the low residual oil in the cake by the analysis of the twin screw press feeding conveying seed movement and force. the alkaline cellulose microcrystalline as a solid agent for removing the free fatty acids(FFA) was prepared, and the optimal adsorption conditions of deacidification and degumming process were investigated, then the process of camellia seed under the low temperature and the camellia oil refined by the adsorption refining was established, and has carried on the comprehensive analysis and evaluation of the new technology. The main results of the paper are as follow.1. The physicochemical properties of the green camellia fruit were studied. The principles of extrusion and grinding rubbing and vibration sieve separation were applied in the design of the peeling machine of green camellia fruit. The water content of the fruit and the roller speed are the main factors affecting the shelling rate. The suitable technological conditions are the moisture content of 40-60%, roller speed of 120-180r/min. Under these conditions, the dehulling rate of the fruit is more than 92%.2. The physicochemical properties of camellia seed were investigated. The principles of the extrusion and grinding and the wind screen composite separation were applied in the design of a hulling machine. The moisture of camellia seed and roller line speed are the main factors affecting the separation effect of shelling. The suitable technological conditions are the moisture of camellia seed of 5-20%, line speed of roller of 8.90-10.00 m·s-1. Then the dehulling rate of camellia seed is greater than 98.5%, and the kernel containing shell is less than 4%, and the shell containing kernel less than 1%.3. The feeding conveying seed movement and force of the twin-screw press were analyzed, and we established the formula for the feeding seed volume transport rate and yield. The formula of the axial compressive stress was derived from the differential equation of the axial compressive force. By the analysis of the double-screw press feeding conveying section, we summed up the effective way to eliminate the smoothbore of seed in a feeding section, for the improvement of double screw press press process and mechanical properties.4. Using the principles of the squeezing screw and the pressing ring joint squeezing, we improves the compression ratio, and increased the length of the pressing cage, and increased the length to diameter ratio, and set the antiskid groove and feed retaining ring, and improved the mechanism of cake, through the calculation of mechanical transmission system, torque divider, a squeezing screw and the pressing ring structure. Then we developed the twin screw press of YZZX20X2 type and YZZX12X2 type. The seed moisture and shelling rate were investigated for influence on the squeezing.The results showed that the optimum conditions are the seed moisture of 8.0%, the kernel shell containing rate of 8.0%, the pressing chamber temperature of 70℃, the oil content of cake by one-press was 4.0%, which is significantly greater than he oil content of cake of 8% produced by the e similar press.5. The process of the sodium montmorillonite(Na-MT) on adsorption of the phospholipids of the camellia seed oil was studied. The results showed that the Na-MT has the significant effect in the adsorption of the phospholipids of the oil, and the stirring rate had little effect on the dephosphorization. The orthogonal experimental results showed that the optimum process parameters are as follow: the dosage of Na-MT 1.2%, the processing time of 25 min, the degumming temperature of 30℃.6. The basic microcrystalline cellulose(AMC) for removing FFA in the oil was preparation and characterized. The effect of AMC on the adsorption of FFA in the low-temperature pressed camellia seed was investigated. The optimum conditions were obtained by the single factor and orthogonal experiment. The results showed that the hydrogen bonding interaction force, crystallinity, chemical reactivity and adsorption capacity of AMC were decreased. The orthogonal experiment results showed that the optimum process parameters were as follows: the time was 2h, the adding amount of AMC was 2.5%, the temperature was 45℃. Under this condition, the acid value of the camellia oil was reduced by 3.15 mg KOH/g.7. The technology of the cold-press and low-temperature refining was compared with the conventional process about production of 30T/ D of camellia seed. The results show that the power consumption of the new technology is 240kwh/t, which reduce by 25.0% compared with 320kwh/t of the traditional process. The coal consumption is 0.10 T / T, and decreased by 71.43% compared with 0.35 T / T of the traditional process. The rate of refining recovery is 97.1%, and increased by 6.1% compared with 91.0% of the traditional process. Compared with the traditional technology of pre-pressing and solvent-extraction, the new technology has the obvious advantages including reducing the investment of equipment and the cost of production. |
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