基于氯化钡滴定法的洗盐效果研究

Study on salt washing effect based on BaCl_2 titration

洗盐效果是盐渍土工程性质和土壤改良研究领域的焦点问题之一。为了研究氯化钡滴定法的合理性以及洗盐后盐渍土性状的改良效果,结合分析盐渍土的洗盐机理,采用蒸馏水浸泡过滤的方法对青海茶卡盐渍土做了洗盐处理,并采用BaCl_2溶液滴定法对该方法洗盐的洗盐效果进行检验,对比了洗盐前后盐渍土的颗粒分析试验和易溶盐离子分析试验。结果表明:茶卡地区盐渍土经过洗盐处理后,土体粗粒组即粒径大于2 mm,按比例减少14.37%,相应细粒组组份增大14.37%;盐渍土中易溶盐含量最少降低至0.096%到非盐渍土的标准。但由于空气中CO_2与水的作用,碳酸氢盐含量增加0.023%。因此使用BaCl_2溶液滴定法检验青海茶卡盐渍土的洗盐效果是有效的方法,且仅适合作为定性研究的判定依据。

The effect of salt washing is one of the key issues in the field of engineering properties and soil improvement of saline soil. In order to study the rationality of the barium chloride titration method and the improvement effect of the saline soil properties after washing with salt,combined with the analysis of the salt washing mechanism of saline soil,the method of soaking and filtering in distilled water was used to do salting treatment on the Chaka saline soil in Qinghai. The salt washing effect of this method was examined and treated with BaCl2 solution titration method. The particle analysis test and salt-soluble ion analysis test of saline soil before and after salt washing were carried out. The results showed that the coarse-grained soil group with a particle size greater than 2 mm reduced in proportion by 14. 37%,and the corresponding fine-grained composition increased by 14. 37%,and the soluble salt content in saline soil was reduced to 0. 096%,which meets the standard of non-saline soil. However,due to the effect of carbon dioxide in the air and water,the bicarbonate content increased by approximately 0. 023%. Therefore,using the BaCl2 solution titration method to test the salt washing effect of Qinghai Chaka saline soil is an effective method,and it is only suitable as a qualitative criterion.