小型变压吸附模块在冰箱控氧保鲜中的应用

通过对变压吸附(PSA)制氧的逆向运用来减少冰箱保鲜盒的氧气浓度,从而有效降低果蔬的呼吸作用,实现长效保鲜.本研究通过对变压吸附制氧进行逆向应用,利用LiX型沸石分子筛对氮气和氧气的选择性吸附,设计并制作了小型变压吸附模块,进一步优化该模块参数为:吸附时间4 s,冲洗孔直径0.5 mm,使排氧体积分数达到93％.对于体积为20 L的冰箱保鲜盒,该小型变压吸附模块的排氧流量为0.3 L//min时,可实现在30 min内将其氧体积分数控制在7.2％以下.将该装置应用于冰箱的保鲜盒中,可高效地将其中的氧气排走并将再生的气体送回保鲜盒中,持续排氧以获得极低氧体积分数的环境,实现果蔬的长效保鲜.

Application of Small Pressure Swing Adsorption Module in Oxygen-Control Preservation of Refrigerators

The reverse application of pressure swing adsorption (PSA) oxygen production can reduce the oxygen concentration in the fresh-keeping box of refrigerator, which can effectively inhibit the respiration of fruits and vegetables and achieve long-term preservation. In this study, a small PSA module was designed and manufactured based on the reverse application of PSA oxygen production, where the selective adsorption of nitrogen and oxygen on LiX zeolite molecular sieve was utilized. The parameters of the small PSA module were further optimized as follows: adsorption time 4 s, diameter of flushing hole 0.5 mm, and oxygen removal volume fraction reached 93%. For a 20 L refrigerator fresh-keeping box, the oxygen volume fraction could be controlled below 7.2% within 30 minutes when the flow rate of oxygen removal in the small PSA oxygen control module was settled as 0.3 L/min. By applying this device to the fresh-keeping box of refrigerator, the oxygen in the box could be efficiently discharged, and the regenerated gas could be sent back to the fresh-keeping box at the same time. Continuous discharge of oxygen provided an environment of extremely low oxygen volume fraction, where the long-term preservation of fruits and vegetables could be achieved.