基于Pitzer热力学模型的高盐废水体系NaCl-Na_(2)SO_(4)-H_(2)O溶解度预测  

Prediction of Solubility of NaCl-Na_(2)SO_(4)-H_(2)O in High Salt Wastewater by Pitzer Thermodynamic Model

作　　者：叶菊梅 刘微 李天涯 李壮 刘焕阳 Ye Jumei;Liu Wei;Li Tianya;Li Zhuang;Liu Huanyang(College of Petroleum Engineering,Liaoning Petrochemical University,Fushun Liaoning 113001,China;College of Chemistry and Chemical Engineering,Liaoning Normal University,Dalian Liaoning 116029,China;Equipment Engineering Department,Liaoning Sales and Storage Branch of PetroChina Co.Ltd.,Shenyang Liaoning 110000,China)

机构地区：[1]辽宁石油化工大学石油天然气工程学院,辽宁抚顺113001 [2]辽宁师范大学化学化工学院,辽宁大连116029 [3]中国石油天然气股份有限公司辽宁销售仓储分公司设备工程部,辽宁沈阳110000

出　　处：《辽宁石油化工大学学报》2021年第5期32-37,共6页Journal of Liaoning Petrochemical University

基　　金：辽宁省教育厅一般项目(L2020023)。

摘　　要：为了研究温度为298.15 K时NaCl-Na_(2)SO_(4)-H_(2)O三元体系的盐类析出规律,采用Pitzer模型预测和计算了该体系的活度系数及溶解度,分析了Na^(+)、Cl^(-)和SO^(2-)_(4)离子活度系数的变化规律及其对应的三元体系相图。结果表明,随着液相中Na_(2)SO_(4)质量分数的增加,Cl^(-)和SO2-4的活度系数无明显变化,而Na^(+)的活度系数呈先增大后下降趋势。当液相中Na_(2)SO_(4)质量分数小于6.8%时,Na+的活度系数上升的平均速率为4.4%;当液相中Na_(2)SO_(4)质量分数为6.8%~14.9%时,Na^(+)的活度系数下降的平均速率为4.1%;当液相中Na2SO4质量分数大于14.9%时,Na^(+)的活度系数下降速率最快,其平均值为8.0%;当液相中NaCl质量分数大于22.9%、Na2SO4质量分数小于6.8%时,随着水分的蒸发,NaCl先析出而Na2SO4后析出;当液相中NaCl质量分数为14.0%~22.9%、Na2SO4质量分数为6.8%~14.9%时,析出顺序相反。In order to study the salt precipitation law of the NaCl-Na_(2)SO_(4)-H_(2)O ternary system at a temperature of 298.15 K,the Pitzer model was used to predict and calculate the activity coefficient and solubility of the system,and the variation of the activity coefficients of Na^(+),Cl^(-) and SO^(2-)_(4) and the corresponding phase diagram of the ternary system were analyzed.The results show that with the increase of the Na_(2)SO_(4) mass fraction,the activity coefficients of Cl-and SO^(2-)_(4) have no obvious change,while the activity coefficient of Na+icreases first and then decreases.When the mass fraction of Na_(2)SO_(4) in the liquid phase is less than 6.8%,the average change rate of the increase in the activity coefficient of Na+is 4.4%.When the mass fraction of Na2SO4 in the liquid phase is between 6.8%and 14.9%,the average change rate of decrease in the activity coefficient of Na+is 4.1%,when the mass fraction of Na_(2)SO_(4) in the liquid phase reaches 14.9%,the activity coefficient of Na+decreases fastest,and the average change rate is 8.0%;when the mass fraction of NaCl in the liquid phase is greater than 22.9%and the mass fraction of Na_(2)SO_(4) is less than 6.8%,as the water evaporates,NaCl precipitates first and Na_(2)SO_(4) precipitates later;when the liquid phase mass fraction of NaCl is 14.0%~22.9%and the mass fraction of Na2SO4 is 6.8%~14.9%,the precipitation order is reversed.

关 键 词：废盐溶液 PITZER模型 活度系数 溶解度预测 相平衡 

分 类 号：TQ150[化学工程—电化学工业]