盐碱地改造用高效阻盐材料的制备及其性能研究

Preparation and Study of Properties of High-Efficiency Salt-Blocking Materials for Saline-Alkali Soil Reconstruction System

摘要:

为改良盐碱土壤，制备了一种隔水阻盐性能优异的超疏水颗粒材料，构建隔水阻盐材料与蓄水模式结合的盐碱地改造体系。以大漠砂为芯材，通过表面覆膜进行疏水改性，探究树脂和微纳米辅材掺量对材料疏水性、抗渗性和透气性的影响规律。利用微型土柱模拟地下水盐迁移过程，探究材料的隔水性能和阻盐性能。结果表明，在树脂、疏水碳酸钙和纳米二氧化硅掺量分别为1.0 %、0.8 %和0.2 %时，材料接触角达到153.6°，耐静水高度达230 mm，并维持良好的透气性能。在微型土柱模拟试验中，隔水阻盐材料对水分蒸发和盐分上移的抑制作用明显，蒸发抑制率为50 %~70 %，盐分抑制率大于99 %且在20次阻盐循环后维持97.5 %以上。

Abstract:

In order to improve saline-alkali soil， a superhydrophobic particle material with an excellent waterproof and salt-blocking performance was prepared， which was used to build a saline-alkali soil reconstruction system with a water-storage mode. Substrate material and desert sand were modified with a hydrophobic coating. The influences of resin content and micro-/nano-material content on the hydrophobicity， impermeability and breathability of the material were studied. A self-designed mini soil-column was used to simulate the migration process of underground saline water， and the waterproof and salt-blocking properties of the prepared materials were explored. The results show that when resin， hydrophobic CaCO₃ and nano-SiO₂ contents were 1.0 %， 0.8 % and 0.2 %， respectively， the material achieved a water contact angle of 153.6°， a water-resistant height of 230 mm， and maintained a good air permeability. The mini soil-column simulation test indicates that the material has a strong inhibition effect on the water evaporation and the upward movement of salt， with an evaporation-inhibiting rate of 50 % to 70 % and a salt-blocking rate of more than 99 %， which maintains 97.5 % after 20 test cycles.