Solid-liquid separation system and process for tail salt liquid generated in production of potash fertilizer from carnallite

Abstract

The invention provides a solid-liquid separation system and a solid-liquid separation process for tail salt liquid generated in production of a potash fertilizer from carnallite, and relates to the technical field of chemical production. The solid-liquid separation system comprises a tail salt liquid collection tank, a pump station, a first-stage thickener, a first-stage vibrating screen machine, a cyclone, a second-stage thickener and a sedimentation tank which are sequentially connected through a conveying pipeline; the cyclone is also connected with a secondary vibrating screen machine; and the first-stage thickener and the second-stage thickener are connected to the clarification tank through pipelines or water tanks. The system is used for treating the tail salt liquid generated during potassium fertilizer production from carnallite, solid and liquid in the tail salt liquid can be separated to the maximum extent finally, and the solid and the liquid which are separated again can enter a production system to be reused. The separated liquid (brine) is high in quality, the solid (tail salt) is controllable in transportation and stacking use, the site use is small, the cost is low, the tail salt liquid generated in a potash fertilizer production workshop can be continuously treated without shutdown, and the production efficiency is high.

Description

technical field [0001] The invention relates to the technical field of chemical production, in particular to a liquid-solid-liquid separation system and process of tail salt produced by carnallite production of potash fertilizer. Background technique [0002] Potassium is one of the three elements of crop nutrition. According to the rough calculation of the Chinese Academy of Agricultural Sciences, the area of ​​soil potassium deficiency in my country currently accounts for about one-fifth of the cultivated land area. However, the development of my country's potash fertilizer industry is slow, and most of them rely on imports, which are far from meeting the needs of my country's agricultural production development. [0003] In the process of potash fertilizer production (refinement of solid low-content potassium chloride raw ore into solid high-content potassium chloride finished potash fertilizer), the generated discharge (tail salt solution) will cause extremely serious po...

AI Technical Summary

Problems solved by technology

However, the development of my country's potash fertilizer industry is slow, and most of it is imported, which is far from meeting the needs of my country's agricultural production development.

[0003] In the process of potash fertilizer production (refining solid low-content potassium chloride raw ore into solid high-content potassium chloride finished potassium fertilizer), the discharge (tail salt liquid) will bring extremely serious pollution to the environment. The tail salt liquid contains solid and liquid state, its solid content ranges from a few percent to tens of percent. In the existing potash fertilizer process, its solid phase (tail salt) cannot be used in potash fertilizer production and is discarded. The traditional treatment method is to The tail salt liquid is discharged into a large enough site (pool) for precipitation, and the solid phase tail salt is cleaned and transferred irregularly according to the size of the site and the amount of solid tail salt, while the liquid phase (brine) is used for reproduction, but a large amount The mud cannot be separated and removed, and part of the mud also enters the reproduction system at the same time, which brings hidden dangers to the subsequent potash fertilizer production

Moreover, the cost of this process is relatively high, and the site requirements are also relatively high.

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