钾盐是中国关乎粮食安全的一种紧缺战略性矿产，近年来，青海柴达木盆地发现多处含钾深层卤水，具有良好的开发潜力。在开发过程中，需要因地制宜地利用太阳能和风能进行盐田日晒蒸发，对有价组分进行初步分离富集。而卤水蒸发实验和相应体系的相平衡与相图研究是盐田蒸发工艺必不可少的基础工作。针对青海某深层含钾卤水进行了室内蒸发实验，研究该卤水的蒸发结晶路线和析盐规律，确定钾盐分离点的控制参数。实验结果表明：卤水的蒸发结晶行为与依据的四元体系相图Na⁺，K⁺，Mg²⁺//Cl^--H₂O（25 ℃）和K⁺，Ca²⁺，Mg²⁺//Cl^--H₂O（25 ℃）基本吻合，析盐顺序为二水石膏（微量）、石盐、光卤石、水氯镁石；卤水中主组分K在卤水密度为1.308~1.398 g/cm³时仅以光卤石矿物形式集中析出，K质量分数为9.80%，析出率为86.54%，有利于后续钾的加工利用；在整个卤水蒸发过程中，微量组分B₂O₃、Br、Li一直在浓缩富集，尤其是B₂O₃和Br，在最终老卤中的含量可富集至2 279.60 mg/L和832.92 mg/L，具有较好的综合利用价值。研究成果为其以后开发利用提供了依据。

Potassium salt ore is a kind of strategic mineral resource which is in short supply.It is vital for the food security in China.In recent years，multiple deep brines containing potassium are found in the Chaidamu basin of Qinghai province.These brines have great development potential.To develope them，evaporation in the salt field must be carried out using the solar energy and wind energy.The preliminary separation and enrichment of the valuable components are achieved by evaporation in the salt field.Brine evaporation experiment and research on phase equilibrium and phase diagram are the essential basic work for evaporation in the salt field.So taking the deep brine in Qinghai province as the research object，the indoor evaporation experiment was carried out.The evaporation route and salt crystallization law of the brine were researched.The main parameters for controling the separation point of the potassium salt precipitation were determined.The experimental results showed that the crystallization route of the brine was consistent with the phase diagrams of Na⁺，K⁺，Mg²⁺//Cl^--H₂O system at 25 ℃ and K⁺，Ca²⁺，Mg²⁺//Cl^--H₂O system at 25 ℃.And the sequence of the mineral crystallization during evaporation was trace dihydrate gypsum，halite，carnallite and bischofite.When the brine density was in the 1.308~1.398 g/cm³ range，potassium of the brine was only precipitated in the form of carnallite mineral，and the precipitation stage was relatively concentrated.So it was beneficial to the processing and utilization of carnallite.The precipitation rate of potassium was 86.54% with potassium content of 9.80%.Trace elements of boron，bromine and lithium were enriched throughout the evaporation process.The contents of boron and bromine in the final tail brine were up to 2 279.60 mg/L and 832.92 mg/L.The two elements of the tail brine was significant for comprehensive utilization.The research result would provide a scientific basis for the later exploitation and utilization of the deep brine containing potassium.