富锂钾硼钙油田水体系介稳相平衡与化学模型研究

Studies on the metastable phase equlibia and chemical model of the unique style of oil-field brine resource containing high concentrations of lithium, potassium, calcium and boron in China is essential to promote the development and utilization of this oil-field brine and to demonstrate the genesis of brine and its evolutionary proess. In this project,the novel experimental methods including the isothermal evaporation method for metastable phase diagram of the muli-systems at differnet temperatures and hypothermia calorimetric method for the thermodynamic properties of heat capcity, heat of mixing, phase transition temperature, enthalpy, entropy, and Gibbs free energy of the binary and ternary salt-water sub-systems of the oil-field brine will be adopted. Combined the experimental measuremental results on metastable phase equilibria and hypothermia calorimetry,a further extends the electrolyte theory on the basis of Pitzer's theory, and a series of the single salt parameters,the mixing-ion interaction parameters, and the judgements of metastable equilibria for the minerals existed in the metastable systems will be obtained. And then, a new predictive chemical model for the unique oil-field brine resources will be farmed based on Pitzer model and its extend through the species borate existed in solution will be introduced to prodicte the the process and the mechanics of the crystallizing-depositing and dissolving-inverting for the changes of brine compostion, the evaporating path, phase transaction of minerals in the oil-field brine system. The research results obtained in this project through the coming 4-year study will provide a series of sifnificant fundmental thermodynamic data of chemical engineering to promote the development of new products and to guide the comprehensive utilization of the oil-field brine resoures.

针对我国特有的富锂钾硼钙新资源类型的油田卤水开发利用，开展具有该油田卤水组成特征的介稳相平衡与化学模型研究，对于揭示卤水成因和演化规律、指导油田水资源开发利用至关重要，乃国际前沿课题。本项目拟创新低温（多温）油田水体系介稳相平衡与溶液热力学性质研究方法和手段，采用等温蒸发法研究油田水资源利用的多温多体系介稳相平衡与相图，低温量热法研究二元、三元子体系的热容、混合热及其相变温度和焓、熵、吉布斯自由能热力学性质。结合介稳相平衡和低温量热法实验研究结果，并引入溶液中硼的不同存在形态，发展Pitzer电解质溶液理论，获取整套油田卤水体系电解质溶液模型参数，构建油田卤水组成变化、盐类矿物结晶和转化的预测化学模型，丰富盐卤硼酸盐化学理论，揭示卤水蒸发、盐类结晶沉积、溶解转化的过程与机制，为这一宝贵新资源类型油田卤水的新产品开发及其综合利用提供重要的化工热力基础数据。

本项目为了促进我国富锂钾硼钙新资源类型的油田卤水开发利用，开展具有该油田卤水组成特征的介稳相平衡与化学模型研究。首先合成了迄今尚无商用的3种钙硼酸盐基础上，创新低温（多温）油田水体系介稳相平衡与溶液热力学性质研究方法，采用等温蒸发法揭示了油田水资源利用的多温多体系介稳相平衡与相图、绝热微量法和U型振荡管精密度法探明了3种固体钙硼酸盐热容与温度关系和含钙硼酸盐水溶液体系的表观摩尔热容、溶解热、偏摩尔体积及其相变温度热力学性质。结合介稳相平衡、量热法和密度法实验研究结果，丰富和发展了Pitzer电解质溶液理论，获取油田卤水体系电解质溶液离子相互作用参数及其温度关联式参数，构建油田卤水相平衡预测化学模型，为这一宝贵新资源类型油田卤水的新产品开发及综合利用提供重要的化工热力基础数据。出版著作和章节3部，发表论文40篇（SCI论文32篇、EI期刊论文1篇、中文核心期刊论文7篇），授权专利7项，参加国际会议3次、组织承办和协办全国会议2个、参加全国性会议4次，交流会议论文25篇，培养博士后2名、博士生2名、硕士生6名，获省部级专利优秀奖1项，国际学术大会Poster奖2项、全国学术会议墙报奖1次。超额完成了本项目任务。