污染微滤膜的超声波辅助清洗实验研究

超声波清洗技术用于清洗酵母菌溶液和大豆分离蛋白(ISP)溶液污染的聚偏氟乙烯(PVDF)微滤膜。实验中所用的超声波频率为40kHz,超声波的强度为1.43～2.85W/cm2。实验结果表明:对于酵母菌溶液污染的微滤膜超声波辅助水洗是恢复水通量的有效方法;而且超声波强度越高,达到相同FR(水通量恢复率)的清洗时间tc越短;但对于大豆分离蛋白溶液污染的微滤膜单纯用超声波辅助水洗的效果相对较差,而超声波辅助NaOH溶液的化学清洗的效果较好,在浓度为3g/L的NaOH溶液超声波辅助清洗6min即可使其FR值达到91%。

Study on Ultrasound-associated Cleaning of Micorfiltration Membrane

Ultrasound (US) cleaning technique was applied to remove fouling of PVDF(polyvinylidene fluoride) microfiltration (MF) membrane, used to be fouled by yeast cell and isolated soybean protein (ISP) solution. The US employed was of 40 kHz frequency and 1.43～2.85 W/cm2 output power. The cleaning effects were determined by the assay of flux recovery rate (FR) and cleaning time. Results showed that the membrane, fouled by yeast cell solution, could be recovered by water cleaning with US irradiation. The cleaning time could be achieved with the same FR by the increase of US intensity. However, for the membrane fouled by ISP solution, it took long time to achieve the same FR with ultrasound-associated water cleaning. In addition, it was also found that the chemical cleaning associated with US irradiation could distinctly enhance the cleaning efficiency, such as to restore 91% of the original membrane water permeability within 6 min by a combination of 3 g/L sodium hydroxide with output power of 1.43 W/cm2 US irradiation.