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发展了一种浓盐水的热力学模型。该模型能够预示在25℃和1大气压下许多普通蒸发盐矿物在氯化物——硫酸盐水中的溶解度。该模型假定,在含水电解质混合物中平均化学计算的离子活度系数的行为,可用 Scatchard 偏离函数以及 Harned定律来描述。在含有一种盐和水的溶液中,其活度系数可用下式表示:logγ_±=-|z_+z_-|AI~(1/2)/(+a°BI~(1/2))+2(V_+V_-/V)(?)I,式中 a°和(?)得自数据回归的盐特殊参数。在几种电解质和水的混合物中,第 i 种组份的(?)可用下式求得:(?)=(?)+∑_(aijyj) j=1,n j≠i,式中 aij 是表示组份 i 和组份 j 相互作用的恒定混合参数,yj 是第 j 组份的离子强度分数。水的活度系数由 Gibbs-Duhem 积分式求得。而且不需要任何附加的参数和假设。在本论文中,求取了 NaCl-KCl-MgCl_2-CaCl_2-H_2O 和 NaCl-MgSO_4-H_2O 体系在25℃和大气压条件下的参数。这些体系中算得的溶解度曲线和预示的不变点溶液组成均与实验数据很一致。此模型具有灵活性,并容易推广到其他体系和更高的温度。
A thermodynamic model of brine has been developed. The model can predict the solubility of many common evaporating salt minerals in chloride-sulphate water at 25 ° C and 1 atmosphere. The model assumes that the average stoichiometric ion activity coefficient in an aqueous electrolyte mixture can be described by the Scatchard’s deviation function and Harned’s law. In a solution containing a salt and water, the activity coefficient can be expressed as follows: logγ_ ± = - | z_ + z_- | AI ~ (1/2) / (+ a ° BI ~ (1/2)) +2 (V_ + V_- / V) (?) I, where a ° and (?) Are derived from the salt-specific parameters of the data regression. In several mixtures of electrolytes and water, the ith component (?) Can be obtained by the following formula: (?) = (?) + Σ_ (aijyj) j = 1, nj ≠ i, where aij is The constant mixing parameter that indicates the interaction of component i with component j, and yj is the ionic strength fraction of component j. Water activity coefficient by Gibbs-Duhem integral obtained. And does not require any additional parameters and assumptions. In this paper, the parameters of NaCl-KCl-MgCl_2-CaCl_2-H_2O and NaCl-MgSO_4-H_2O systems at 25 ℃ and atmospheric pressure were obtained. The solubility curves calculated in these systems and the predicted invariant solution compositions are in good agreement with the experimental data. This model is flexible and easy to generalize to other systems and to higher temperatures.