气隙式膜蒸馏处理模拟放射性废水

摘要

Air gap membrane distillation was employed for the treatment of simulate radioac-tive wastewater including the simple ingredient,which contained only 1 g/L Sr2 + ,and the complex ingredient that mixed Co2 + ,Sr2 + ,Na+ ,Ca2 + with the mass concentration of 10 g/L, separately.The research results show that the desalination rates of Sr2 + in the simple ingre-dient of simulated radioactive wastewater achieve 99.999%,and the decontamination factor of which is more than 10 5 .The desalination rates of Sr2 + and Co2 + in the complex ingredi-ent,which mixed Co2 + ,Sr2 + ,Na+ ,Ca2 + ,are all nearly 100%,and the decontamination factors of Sr2 + and Co2 + reach 1 × 10 6 and 1 × 10 7 ,separately.Enhancing the temperature and flow rate of feed can make contribution to an increase in the membrane flux,effectively. In the case that the temperature of feed is 75 ℃ and flow rate of feed is 7 L/min,the mem-brane fluxes are 4.15 kg/(m2 · h)and 3.88 kg/(m2 · h)for the simple ingredient and complex ingredient simulated radioactive wastewater,respectively.The results in this work suggest that the membrane distillation as a novel technology will play an important role in the treatment of radioactive wastewater.%对采用自制气隙式膜蒸馏装置净化处理质量浓度为1 g/L Sr2+和离子质量浓度均为10 g/L 的 Co2+、Sr2+、Na+、Ca2+四种离子混合模拟放射性废水进行了研究。结果表明：膜蒸馏技术对1 g/L Sr2+料液中 Sr2+截留率可以达到99.999%以上,去污系数(DF)在105以上；处理离子质量浓度均为10 g/L 的 Co2+、Sr2+、Na+、Ca2+四种离子混合料液时,膜蒸馏对 Sr2+、Co2+截留率均接近100%,DF(Sr2+)达1×106,DF(Co2+)达1×107；料液温度和料液流速对膜通量有一定影响,无论是提高料液温度,还是增加料液流速,均可以有效提高膜通量。在保证净化效果的情况下,在料液温度75℃,料液流速7 L/min 时,处理1 g/L Sr2+膜通量可以达到4.15 kg/(m2·h)。对离子质量浓度均为10 g/L 的 Co2+、Sr2+、Na+、Ca2+四种离子混合料液进行处理时,膜通量也达到3.88 kg/(m2·h)。