基于酸碱平衡曝气水垢去除工艺的酸量模型

摘要

Descaling by acid-alkali balance aeration method removes the hydrogen carbonate in the water by adding acid andreduces alkalinity in raw water.Aeration blows off the dissolved CO2from the water,so that the the pH of effluent water was similar to the pH of raw water to achieve the goal of removing moisture.Based on the principles of the acid-alkali balance and transformation,as well as the solubility relationship among carbon dioxide,calcium carbonate and magnesium hydroxide in water,we established the calculation model of the amount of adding acid aiming to remove scale.And we have chosen nine different water samples to verify this model.It was calculated that the relative error be-tween stoichiometric model and actual amount of adding acid was less than 7 %,R2=0.9 8.We regarded the bicarbonate which produced calcium carbonate as the main part of the removal,after the sensitivity analysis of each influencing factor was performed,based on which a simplified model was es-tablished where the relative error between the simplified model and the actual amount of adding acid was less than 1 4 %,R2=0.9 7.The establishment and simplification of the acid calculation model pro-vided a theoretical basis for the amount of acid of descaling by acid-alkali balance aeration method which also provided theoretical support for the promotion and implementation of descaling by acid-alkali bal-ance aeration method.%酸碱平衡曝气水垢去除工艺通过加酸去除水中部分的碳酸氢根,降低原水碱度,曝气再将水中溶解的CO2吹脱出来,使得出水与原水的 p H 相近,来达到除水垢目的.基于水中酸碱平衡及转化原理,水中二氧化碳、碳酸钙和氢氧化镁的溶度积关系等建立了以去除水垢为目标的加酸量的化学计量模型,并选用9种不同水样对模型进行验证,得出化学计量模型加酸量与实际加酸量相对误差小于7 %,R2=0.98;针对其各影响因素进行敏感性分析,得出产生碳酸钙的碳酸氢根为主要去除部分,并以此建立了简化模型,得出简化模型的加酸量与实际加酸量相对误差小于14 %,R2=0.97.加酸量计算模型的建立与简化为酸碱平衡曝气法除水垢的加酸量确定提供了最重要的理论依据,也为酸碱平衡曝气法除水垢的推广与实施提供了最重要的理论支撑.