离子交换树脂在造纸废水脱盐中的应用研究

Application of Ion Exchange Resin in Desalination of Papermaking Wastewater

关键词:  离子交换树脂  脱盐  造纸废水

Key Words:ion exchange resin  desalination  papermaking wastewater

摘要:本研究采用732氢型阳离子交换树脂（以下简称阳离子树脂）、201×7氢氧型阴离子交换树脂（以下简称阴离子树脂）对造纸废水进行脱盐处理，研究了树脂在静态吸附和动态吸附过程中对造纸废水中离子的吸附性能。结果表明，阳离子树脂对造纸废水中Na⁺、Ca²⁺、Mg²⁺和Fe³⁺均有明显的去除效果，阴离子树脂对Cl^-和SO₄^2-有明显的去除效果。吸附时间为15 min、阳离子树脂∶阴离子树脂=1.2∶1.4（质量比），阳、阴离子树脂联用脱盐效果最佳。动态吸附过程中，随着流速增大，阳、阴离子树脂对离子的去除效果逐渐减弱，阳离子树脂适宜动态吸附流速为4~12 BV/h，阴离子树脂适宜动态吸附流速为4~10 BV/h。阳离子树脂的最佳再生条件为动态吸附流速4 BV/h、质量分数4%、体积3 BV，阳离子树脂再生率为94%；阴离子树脂的最佳再生条件为动态吸附流速4 BV/h、质量分数5%、体积3 BV、阴离子树脂再生率为84%。饱和吸附后树脂多次充分再生情况下，阳离子树脂再生率保持在90%以上，阴离子树脂再生率保持在80%以上。

Abstract:In this study， 732 hydrogen type cation exchange resin （cation resin） and 201×7 hydroxide anion exchange resin （anion resin） were used for the desalination of papermaking wastewater. The adsorption properties of the resin for ions in papermaking wastewater during the static adsorption and dynamic adsorption were studied. The results showed that cation resin had obvious removal effect on Na⁺， Ca²⁺， Mg²⁺， and Fe³⁺ in the papermaking wastewater， and anion resin had obvious removal effect on Cl^- and SO₄^2-. The optimal static adsorption time was 15 min， and the desalting effect was best when combined with cation resin and anion resin mass ratio was 1.2∶1.4. In the process of dynamic adsorption， with the increase of flow velocity， the removal effect of resin on ions gradually weakened. The appropriate dynamic adsorption velocity of cation resin should be 4~12 BV/h， and the appropriate dynamic adsorption velocity of anion resin should be 4~10 BV/h. The optimal regeneration conditions of cation resin were the dynamic adsorption velocity of regenerated liquid 4 BV/h， the concentration of 4%， the volume of 3 BV， and the regeneration rate of 94%. The optimal regeneration conditions of cation resin were the dynamic adsorption velocity of regenerated liquid 4 BV/h， the concentration of 5%， the volume of 3 BV， and the regeneration rate of 84%. When the resin was fully regenerated several times after saturated adsorption， the regeneration rate of cation resin was kept above 90%， and that of anion resin was kept above 80%.