摘要
机械蒸汽压缩(MVC)蒸发处理渗滤液过程中,Ca^(2+)和Mg^(2+)的大量存在会导致结垢及浓缩液后续处理困难等问题。通过静态吸附实验,探索了732型阳离子交换树脂对渗滤液中Ca^(2+)、Mg^(2+)的吸附特性。实验结果表明,在pH=7、温度为30℃、732型阳离子交换树脂投加量为8g/L、吸附时间为30 min的条件下,对于Ca^(2+)和Mg^(2+)(摩尔比为3∶5)的质量浓度为2 000mg/L的混合溶液,两者的去除率分别为88.8%、68.3%。732型阳离子交换树脂对Ca^(2+)和Mg^(2+)的吸附行为均符合Langmuir吸附等温方程,相关性系数(R2)分别为0.992 5、0.952 3。利用732型阳离子交换树脂处理实际渗滤液,吸附条件与混合溶液相同,结果表明,对实际渗滤液中Ca^(2+)和Mg^(2+)的去除率分别达到为69.9%、70.9%。经过732型阳离子交换树脂吸附预处理后的渗滤液再经MVC蒸发处理,可有效减少MVC蒸发过程中的结垢,并降低浓缩液后续处理成本。
The existence of Ca^2＋ and Mg^2＋ in the leachate during the mechanical vapor compression （MVC） treatment will lead to some problems such as scale formation and the difficulty of the subsequent processing. In this work,the adsorption characteristics of 732 cation exchange resin on Ca^2＋ and Mg^2＋ in the synthetic solutions using static adsorption method was studied. The results showed that the removal rates of Ca^2＋ and Mg2. with mass concen- trations of 200 mg/L were 88.8 % and 68.3 %, respectively, under the condition of 8 g/L 732 cation exchange resin, 30℃, pH= 7.0 and 30 min adsorption time. The adsorption process followed the Langmuir isothermal equation,with correlation coefficients （R2） of 0.992 5 （Ca^2＋ ） and 0.952 3 （Mg^2＋ ） ,respectively. Then the real leachate was used for the adsorption and it found that the removal rates of Ca^2＋ and Mg^2＋ were 69.9% and 70.9%, respectively, using a similar condition with the synthetic solution. The leachate effluent obtained after 732 cation exchange resin treatment was suitable for the subsequent evaporation using MVC to inhibit scaling and to decrease the treatment cost of concen- tration.
出处
《环境污染与防治》
CAS
CSCD
北大核心
2017年第2期179-184,190,共7页
Environmental Pollution & Control
基金
上海市科研计划项目(No.13DZ0511600)
