Significant effort has been made to measure and understand the surface charge of CaCO₃ and Mg(OH)₂ particles. Many laboratory experiments have been reported on zeta potential of natural and prepared CaCO₃ and a few have also been published for Mg(OH)₂, however, there are very few reported measurements of zeta potential of CaCO₃ and Mg(OH)₂ particles at conditions relevant to lime softening, despite lime softening being a common and established process for water treatment. The present study aims to understand the interactions and electrokinetic properties of these two particles in lime softening. Effects of various experimental parameters such as pH, temperature, aging, inorganic carbon (CO₃²⁻/HCO₃⁻), and divalent cations (Ca²⁺/Mg²⁺) on the electrokinetic properties (i.e. zeta potential) of CaCO₃ and Mg(OH)₂ particles were individually studied. The interactions between humic acid (mimicking natural organic matter), silicate (representing silica), clay (mimicking suspended solids) and CaCO₃/Mg(OH)₂ particles were studied, as well as the interactions between CaCO₃ and Mg(OH)₂. Thermodynamic modeling was used to predict precipitates as a function of solution chemistry and assist with data interpretation. The results provide considerable insight into factors that are of importance to lime softening.

为了测量和理解CaCO ₃和Mg（OH）₂颗粒的表面电荷，已经做出了巨大的努力。已经报道了许多关于天然和制备的CaCO _3的ζ电势的实验室实验，也已经发表了一些有关Mg（OH）₂的ζ电势，但是，很少有关于CaCO ₃和Mg（OH）₂的ζ电势测量的报道。尽管石灰软化是水处理中常见的既定方法，但在与石灰软化有关的条件下仍会产生颗粒。本研究旨在了解石灰软化过程中这两个粒子的相互作用和电动特性。各种实验参数，例如pH，温度，老化，无机碳的影响（CO ₃ ^{2- /} HCO ₃ ^- ），和二价阳离子（钙²⁺ / Mg的²⁺）上的电动性质（即ζ电位）的CaCO的₃分别研究了Mg（OH）₂颗粒。腐殖酸（模仿天然有机物），硅酸盐（代表二氧化硅），粘土（模仿悬浮固体）和CaCO之间的相互作用_研究了3 / Mg（OH）₂颗粒，以及CaCO ₃和Mg（OH）₂之间的相互作用。使用热力学建模来预测沉淀物随溶液化学性质的变化，并有助于数据解释。结果提供了对石灰软化重要因素的大量见解。