察尔汗盐湖矿区卤水氨浓度分布特征研究OA

The production scale of food and pharmaceutical grade potassium chloride in our country is small,and it's difficult to meet the market demand.The use of low ammonia nitrogen brine for direct production of food grade and pharmaceutical grade potassium chloride is a feasible way to improve product quality and reduce production costs.The key to selecting low ammonia nitrogen brine is to clarify the distribution characteristics of ammonia in salt lake brine.This article takes the mining area of Qarhan Salt Lake as the research object.Based on the current status of resource development in the mining area,samples were taken from the original brine in both horizontal and vertical directions,and representative data were selected for analysis.The results show that the brine in the mining area of Qarhan Salt Lake can be divided into three high ammonia areas and four low ammonia areas.Among the three high ammonia areas,the first and second high ammonia areas are caused by mining and dissolution operations,while the third high ammonia area may be caused by leakage and diffusion of flotation tailings into the brine tank during recycling.Among the four low ammonia areas,the distribution of areas ① and ③ is relatively concentrated,while the distribution of areas ② and ④ is relatively narrow.However,area ④ is closer to the processing plant,making brine extraction and transportation more convenient.Therefore,it is more appropriate to select the range of ammonia mass concentration of 20～40 mg/L in areas ③ and ④ as the raw material collection point.The Kruskal-Wallis test results indicate that the mass concentration of ammonia in brine is related to its location.Through Dunnett's T3 multiple comparisons,it can be seen that the mass concentration of ammonia in brine at a depth of 1 m does not show strong significance with the groups of 12 m,15 m,16 m,17 m,and 19 m.The reason for the higher mass concentration of ammonia in shal-low brine is mainly due to the lower density of organic ammonia in the brine,which is suspended in the upper layer of the brine;The higher concentration of ammonia in deeper layers is due to the natural permeation of solvents into the brine well.