阅读说明：本技术 一种利用光卤石矿提取氯化钾的高回收率生产工艺 (High-recovery-rate production process for extracting potassium chloride by utilizing carnallite ore ) 是由 甘顺鹏 谢超 余俊 季荣 蒋世鹏 郑贤福 胡勇 罗稳 冯文平 于 2019-09-06 设计创作，主要内容包括：一种利用光卤石矿提取氯化钾的高回收率生产工艺：将光卤石分解所需淡水加入到工艺后端,用于粗钾和尾矿洗涤,得到KCl含量偏高、MgCl-2不饱和的低镁高钾母液,通过浓密池将所述工艺后端产生的低镁高钾母液返回工艺前端分解光卤石。利用本发明,可以有效提高分解淡水量的控制精度,既保证氯化钾产品质量,也大大提高了加工工艺的氯化钾综合回收率,克服了传统工艺分解淡水量难于控制、综合回收率低等缺点,显著提高了钾资源利用率和钾肥企业生产效益。本发明工艺流程简单、环境污染小、生产成本低、所得氯化钾产品质量好、回收率高。(A high recovery rate production process for extracting potassium chloride by utilizing carnallite ore comprises the following steps: adding fresh water required by decomposing carnallite into the rear end of the process for washing crude potassium and tailings to obtain MgCl with higher KCl content 2 And returning the low-magnesium high-potassium mother liquor generated at the rear end of the process to the front end of the process through a thickening tank to decompose carnallite. The invention can effectively improve the control precision of the decomposed fresh water quantity, not only ensures the quality of potassium chloride products, but also greatly improves the comprehensive recovery rate of potassium chloride in the processing technology, overcomes the defects of difficult control, low comprehensive recovery rate and the like of the decomposed fresh water quantity in the traditional technology, and obviously improves the utilization rate of potassium resources and the production benefit of potassium fertilizer enterprises. The invention has the advantages of simple process flow, little environmental pollution, low production cost, good quality of the obtained potassium chloride product and high recovery rate.)

1. A high-recovery-rate production process for extracting potassium chloride by utilizing carnallite ore comprises the following steps:

(1) crushing carnallite ore and adding the crushed carnallite ore into a decomposition crystallizer;

(2) adding refined potassium mother liquor and size mixing mother liquor into a decomposition crystallizer to fully decompose carnallite and obtain decomposed crystallization underflow pulp and decomposed crystallization overflow;

(3) conveying the decomposed crystallization underflow ore pulp obtained in the step (2) to a No. 1 vibrating screen for screening, conveying oversize products to an ore pulp washing and stirring barrel, and conveying undersize ore pulp to a No. 1 thickening tank for thickening;

(4) adding fresh water and the pulp mixing mother liquor into the pulp washing and stirring barrel in the step (3), and washing oversize products of the No. 1 vibrating screen to obtain washed pulp;

(5) conveying the washed ore pulp obtained in the step (4) to a No. 2 vibrating screen for screening, conveying oversize products to a tailing washing stirring barrel, and returning the ore pulp under the screen to the decomposing crystallizer in the step (1);

(6) conveying the decomposed crystal overflow obtained in the step (2) to a No. 2 thickening tank for thickening, conveying the bottom flow of the No. 2 thickening tank to a flotation dosing and size mixing stirring barrel, and conveying the overflow to a salt pan natural evaporation crystallization or size mixing mother liquor storage tank or a chemical evaporation workshop for forced evaporation crystallization;

(7) sending the underflow generated by the thickening in the thickening tank No. 1 in the step (3) to a dosing and size mixing stirring barrel, and sending the overflow to a salt pan natural evaporation crystallization tank or a size mixing mother liquor storage tank or a chemical evaporation workshop for forced evaporation crystallization;

(8) adding a flotation reagent and a pulp mixing mother solution into the dosing and pulp mixing stirring barrel in the step (7), and fully stirring to obtain dosed ore pulp;

(9) feeding the ore pulp after the chemicals are added in the step (8) to flotation equipment for flotation to obtain flotation concentrate ore pulp and flotation tailing ore pulp, feeding the flotation concentrate ore pulp to a crude potassium filter for filtering, and feeding the flotation tailing ore pulp to a tailing washing stirring barrel for washing;

(10) adding washing fresh water into a tailing washing stirring barrel to wash the tailing pulp obtained in the step (9) and oversize products of the No. 2 vibrating screen in the step (5), and sending the washed pulp to a tailing thickening tank for thickening;

(11) after the washed tailing pulp is thickened by a tailing thickening tank, the bottom of the thickening tank is conveyed to a tailing filter for filtering, and overflow mother liquor returns to a size mixing mother liquor storage tank;

(12) filtering the tailings by a tailing filter to obtain tailings and a tailing mother liquor, wherein the tailings are sent to a salt field tailing dam or an underground filling station, and the tailing mother liquor returns to a tailing thickening tank;

(13) filtering the flotation concentrate ore pulp obtained in the step (9) by using a crude potassium filter to obtain crude potassium and crude potassium mother liquor, sending the crude potassium to a crude potassium washing stirring barrel for washing, and sending the crude potassium mother liquor to a size mixing mother liquor storage tank;

(14) adding fresh water for washing into the crude potassium washing and stirring barrel in the step (13) to wash the crude potassium to obtain fine potassium pulp;

(15) and (3) sending the fine potassium ore pulp obtained in the step (14) to a fine potassium filter for filtering to obtain fine potassium and a fine potassium mother solution, sending the fine potassium to a drying workshop for dehydration and drying to obtain a potassium chloride product, and returning the fine potassium mother solution to a decomposition crystallizer for decomposing and crystallizing carnallite.

2. The high recovery production process for extracting potassium chloride from carnallite according to claim 1 wherein: in the step (1), the carnallite ore comprises tedded carnallite ore in a salt pan and underground native carnallite ore, and the main components of the carnallite ore comprise, by mass, 15.49% -18.31% of KCl and MgCl₂15.62 to 18.77 percent of the total weight of the carnallite ore, and 38.98 to 48.12 percent of NaCl, and the carnallite ore is crushed to be less than or equal to 8 mm.

3. The high recovery production process for extracting potassium chloride from carnallite according to claim 1 or 2 wherein: the step (2) and the step (1)5) Wherein the refined potassium mother liquor is a filtrate obtained by washing, washing and filtering crude potassium, and the mass percentage of the main salt components of the refined potassium mother liquor is 10.57-11.36 percent of KCl and MgCl₂ 1.92%～2.43%、NaCl 16.19%～16.63%。

4. The high-recovery production process for extracting potassium chloride from carnallite according to any one of claims 1 to 3, wherein: in the steps (2), (4), (8), (11) and (13), the size mixing mother liquor is a mixed mother liquor of a crude potassium mother liquor and an overflow mother liquor of a tailing thickening tank, wherein MgCl is contained₂Unsaturated, the main salt components are as follows by mass: KCl 4.05-4.31% and MgCl₂17.85%～20.74%、NaCl 2.26%～3.20%。

5. The high recovery production process for extracting potassium chloride using carnallite according to any one of claims 1 to 4 wherein: in the steps (2) and (6), the decomposition crystallization overflow is a decomposition mother liquor containing a small amount of potassium chloride fine crystals, and the mass percentage of main salt components of the decomposition mother liquor is KCl 3.53-3.85 percent and MgCl₂ 25.21%～26.33%、NaCl 1.15%～2.01%。

6. The high recovery production process for extracting potassium chloride from carnallite according to any one of claims 1 to 5 wherein: in the steps (3) and (5), the vibrating screen is a high-frequency vibrating screen, the size of the screen hole is 0.75 mm-1 mm, and the screening washing mother liquor is the size mixing mother liquor.

7. The high recovery production process for extracting potassium chloride from carnallite according to any one of claims 1 to 6 wherein: in the steps (4) and (10), the washing fresh water is fresh water obtained by collecting, precipitating and clarifying various production sewage generated in a production workshop.

8. The high recovery production process for extracting potassium chloride from carnallite as recited in claim 7, wherein: the various production sewages are mechanical sealing wastewater, cooling water and working platform flushing water which are generated in a production workshop.

9. The high recovery production process for extracting potassium chloride from carnallite according to any one of claims 1 to 8 wherein: in the step (14), the fresh water is fresh water.

Technical Field

The invention relates to a production process of potassium chloride, in particular to a high-recovery-rate production process for extracting potassium chloride by utilizing carnallite.

Background

The agricultural potassium chloride fertilizer in China is generally obtained by adopting a decomposition-direct flotation or decomposition crystallization-direct flotation process. However, these two processes often involve adding fresh water at the front end of the process (i.e. the decomposition or decomposition crystallization step) to decompose the carnallite before flotation, as disclosed in CN 107739037A, CN 102963912A, CN 204079502U. The method for decomposing carnallite by adding fresh water at the front end of the process has the defects that the amount of decomposed fresh water is not easy to control, the amount of the fresh water is less, and MgCl of the decomposed liquid is not easy to control₂The concentration and the viscosity are both increased, the decomposition speed is slowed down, the entrainment rate of flotation foam impurities is increased, the crude potassium grade is obviously reduced (the crude potassium grade of the Qinghai Chaer salt lake is generally between 58% and 70%), the washing fresh water quantity is increased when the flotation foam is subjected to size mixing and repulping washing, otherwise the quality of a final product does not reach the standard, but after the washing fresh water quantity is increased, the washing recovery rate and the yield are obviously reduced; if the amount of the decomposed fresh water is increased, MgCl will be added to the decomposed solution₂The concentration, viscosity and flotation froth impurity entrainment rate are all reduced, the flotation concentrate grade is improved, but the recovery rate of the decomposition process and the whole system is also obviously reduced.

In order to ensure the product quality in the production of potassium fertilizer production enterprises in China, a large amount of excessive fresh water is generally added during decomposition or decomposition crystallization and repulping washing, and the ore loading is continuously increased after the yield is reduced so as to complete heavy production tasks, so that the consumption speed of raw ores is faster and faster, the production load is larger and larger, the equipment failure rate is higher and higher, and the resource utilization rate and the enterprise production benefits are continuously reduced. At present, when the salt pan carnallite is adopted in China to process and extract potassium chloride products, the processes of decomposition, crystallization, flotation and washing are included, the comprehensive recovery rate of the processing technology is only 60%, and in addition, the recovery rate loss caused by salt pan waste salt, brine leakage and entrainment is added, the recovery rate of the potassium chloride in the whole process from raw brine to the final potassium chloride product is only about 40%, and the resource utilization rate is very low.

The technical scheme disclosed in CN 107572552A, CN 108862328 is to produce potassium chloride products by using a sieving-reverse flotation-cold crystallization mixing process and a reverse flotation-cold crystallization process, respectively, although their KCl recovery rates are high, the cost of the comprehensive chemical agent of the reverse flotation-cold crystallization process is several times higher than that of the comprehensive chemical agent of the decomposition or decomposition crystallization-direct flotation process due to the high price of the reverse flotation collector, so that the market application of the process is limited.

Disclosure of Invention

The invention aims to solve the technical problem of providing a high-recovery-rate production process for extracting potassium chloride by utilizing carnallite ore, which has the advantages of good product quality, high recovery rate, easy operation, low production cost and environmental friendliness and is suitable for large-scale production.

The technical scheme adopted by the invention for solving the technical problems is as follows: a high-recovery-rate production process for extracting potassium chloride by utilizing carnallite ore comprises the following steps:

(1) crushing carnallite ore and adding the crushed carnallite ore into a decomposition crystallizer;

(2) adding refined potassium mother liquor and size mixing mother liquor into a decomposition crystallizer to fully decompose carnallite and obtain decomposed crystallization underflow pulp and decomposed crystallization overflow;

(3) conveying the decomposed crystallization underflow ore pulp obtained in the step (2) to a No. 1 vibrating screen for screening, conveying oversize products to an ore pulp washing and stirring barrel, and conveying undersize ore pulp to a No. 1 thickening tank for thickening;

(4) adding fresh water and the pulp mixing mother liquor into the pulp washing and stirring barrel in the step (3), and washing oversize products of the No. 1 vibrating screen to obtain washed pulp;

(5) conveying the washed ore pulp obtained in the step (4) to a No. 2 vibrating screen for screening, conveying oversize products to a tailing washing stirring barrel, and returning the ore pulp under the screen to the decomposing crystallizer in the step (1);

(6) conveying the decomposed crystal overflow obtained in the step (2) to a No. 2 thickening tank for thickening, conveying the bottom flow of the No. 2 thickening tank to a flotation dosing and size mixing stirring barrel, and conveying the overflow to a salt pan natural evaporation crystallization or size mixing mother liquor storage tank or a chemical evaporation workshop for forced evaporation crystallization;

(7) sending the underflow generated by the thickening in the thickening tank No. 1 in the step (3) to a dosing and size mixing stirring barrel, and sending the overflow to a salt pan natural evaporation crystallization tank or a size mixing mother liquor storage tank or a chemical evaporation workshop for forced evaporation crystallization;

(8) adding a flotation reagent and a pulp mixing mother solution into the dosing and pulp mixing stirring barrel in the step (7), and fully stirring to obtain dosed ore pulp;

(9) feeding the ore pulp after the chemicals are added in the step (8) to flotation equipment for flotation to obtain flotation concentrate ore pulp and flotation tailing ore pulp, feeding the flotation concentrate ore pulp to a crude potassium filter for filtering, and feeding the flotation tailing ore pulp to a tailing washing stirring barrel for washing;

(10) adding washing fresh water into a tailing washing stirring barrel to wash the tailing pulp obtained in the step (9) and oversize products of the No. 2 vibrating screen in the step (5), and sending the washed pulp to a tailing thickening tank for thickening;

(11) after the washed tailing pulp is thickened by a tailing thickening tank, the bottom of the thickening tank is conveyed to a tailing filter for filtering, and overflow mother liquor returns to a size mixing mother liquor storage tank;

(12) filtering the tailings by a tailing filter to obtain tailings and a tailing mother liquor, wherein the tailings are sent to a salt field tailing dam or an underground filling station, and the tailing mother liquor returns to a tailing thickening tank;

(13) filtering the flotation concentrate ore pulp obtained in the step (9) by using a crude potassium filter to obtain crude potassium and crude potassium mother liquor, sending the crude potassium to a crude potassium washing stirring barrel for washing, and sending the crude potassium mother liquor to a size mixing mother liquor storage tank;

(14) adding fresh water for washing into the crude potassium washing and stirring barrel in the step (13) to wash the crude potassium to obtain fine potassium pulp;

(15) and (3) sending the fine potassium ore pulp obtained in the step (14) to a fine potassium filter for filtering to obtain fine potassium and a fine potassium mother solution, sending the fine potassium to a drying workshop for dehydration and drying to obtain a potassium chloride product, and returning the fine potassium mother solution to a decomposition crystallizer for decomposing and crystallizing carnallite.

The method is different from the traditional process in that fresh water required by decomposing carnallite is added to the rear end of the process and is used for washing crude potassium and tailings to obtain MgCl with higher KCl content₂The unsaturated low-magnesium high-potassium mother liquor returns the low-magnesium high-potassium mother liquor generated at the rear end of the process to the front end of the process for decomposing carnallite through the plurality of thickening tanks, so that the control precision of the decomposed fresh water is effectively improved, the quality of potassium chloride products is ensured, the comprehensive recovery rate of potassium chloride of the processing process is greatly improved, the defects that the decomposed fresh water is difficult to control, the comprehensive recovery rate is low and the like in the traditional process are overcome, unexpected technical effects are generated, and the utilization rate of potassium resources and the production benefits of potassium fertilizer enterprises are remarkably improved.

Further, in the step (1), the carnallite ore comprises salt field tedded carnallite ore and underground native carnallite ore, and the main salt components of the carnallite ore comprise, by mass, 15.49% -18.31% of KCl and MgCl₂15.62 to 18.77 percent of the total weight of the carnallite ore, and 38.98 to 48.12 percent of NaCl, and the carnallite ore is crushed to be less than 8 mm.

Further, in the step (2) and the step (15), the refined potassium mother liquor is a filtrate obtained by washing, washing and filtering crude potassium, and the mass percentage of main salt components of the filtrate are 10.57-11.36% of KCl and MgCl₂ 1.92%～2.43%、NaCl 16.19%～16.63%。

Further, in the steps (2), (4), (8), (11) and (13), the size mixing mother liquor is a mixed mother liquor of crude potassium mother liquor and overflow mother liquor of a tailing thickening tank, wherein MgCl is contained₂Unsaturated, the main salt components are as follows by mass percent: KCl 4.05-4.31% and MgCl₂ 17.85%～20.74%、NaCl 2.26%～3.20%。

Further, in the steps (2) and (6), the decomposition crystallization overflow is a decomposition mother liquor containing a small amount of potassium chloride fine crystals, and the mass content of main salt components of the decomposition mother liquor is KCl 3.53-3.85 percent, and MgCl₂ 25.21%～26.33%、NaCl 1.15%～2.01%。

Further, in the steps (3) and (5), the vibrating screen is a high-frequency vibrating screen, the size of the screen hole is 0.75 mm-1 mm, and the screening washing mother liquor is the size mixing mother liquor.

Further, in the steps (4) and (10), the washing fresh water is fresh water obtained by collecting, precipitating and clarifying various production sewage such as production workshop mechanical seal water, cooling water, working platform flushing water and the like, and is used for dissolving KCl in tailings and reducing the KCl grade of the tailings.

Further, in the step (14), the crude potassium is washed by fresh water.

The invention has the beneficial effects that: the processing recovery rate of the potassium chloride is obviously improved by adjusting the process flow, and the process flow is simple, easy to operate, low in production cost, less in environmental pollution, good in product quality and suitable for large-scale production.

Detailed Description

The present invention will be further described with reference to the following examples.

The carnallite used in the examples described below was a solid carnallite in the ground.

Example 1

(1) Mixing carnallite ore (main salt component mass content is KCl 17.17%, MgCl)₂18.77 percent and NaCl 38.98 percent) are conveyed into the decomposing crystallizer by a rubber belt conveyor, and the ore loading of the carnallite is 200 t/h;

(2) adding a slurry-adjusting mother liquor (250 m) into a cold decomposition crystallizer³The mass content of the main components is KCl 4.05 percent and MgCl₂18.39%, NaCl 2.35%) and refined potassium mother liquor (8.5 m)³The mass content of the main components is KCl 10.57 percent and MgCl₂2.43 percent of NaCl and 16.63 percent of NaCl) carries out decomposition and crystallization on the carnallite to obtain decomposed crystallization underflow pulp and decomposed crystallization overflow;

(3) decomposing the crystal underflow slurry (273 m)³H) feeding to No. 1 vibrating screen for sieving (mesh diameter is 0.75mm), and adding decomposition mother liquor (64 m)³The mass content of main components is KCl 3.67 percent and MgCl₂25.52 percent of NaCl and 1.15 percent of NaCl) as screening washing water, and oversize products (49t/h, the mass content of main components is KCl 5.97 percent and MgCl₂89.93% and NaCl 1.53%) are sent to a screening washing stirring barrel for washing, and pulp (302 m) under the screen is obtained³H) sending the mixture to a No. 1 thickening tank for thickening;

(4) overflowing the tailing thickening tankMother liquor (35 m)³The mass content of the main components is KCl 4.05 percent and MgCl₂18.39%, NaCl 2.35%) and fresh water (15 m)³Adding fresh water obtained by collecting, precipitating and clarifying various production sewage such as production workshop mechanical seal water, cooling water, working platform flushing water and the like into a screening, washing and stirring barrel to wash oversize products of a No. 1 vibrating screen to obtain washed ore pulp (81 m)³/h)；

(5) The washed ore pulp obtained by the screening, washing and stirring barrel is sent to a No. 2 vibrating screen (the diameter of a screen hole is 0.75mm) for screening, and meanwhile, the size mixing mother liquor (28 m) is added³The mass content of the main components is KCl 4.05 percent and MgCl₂18.39 percent and NaCl 2.35 percent) as screening flushing water, and oversize products are sent to a tailing washing stirring barrel and undersize ore pulp (76 m)³The mass content of the main components is KCl 4.05 percent and MgCl₂18.39% and NaCl 2.35%) back to the decomposing crystallizer;

(6) overflow of decomposed crystals (48 m)³The mass content of main components is KCl 3.67 percent and MgCl₂25.52 percent of NaCl and 1.15 percent of NaCl) are sent to a No. 2 thickening tank for thickening, and the underflow of the No. 2 thickening tank (0.65 m)³H) sending the mixture to a flotation dosing and pulp mixing stirring barrel, and overflowing the mixture (47 m)³The mass content of main components is KCl 3.67 percent and MgCl₂25.52% and NaCl 1.15%) are sent to a salt pan for natural evaporation and crystallization;

(7) no. 1 thickening tank underflow (211 m)³H) is sent to a dosing and size mixing stirring barrel and overflows (91 m)³H) sending to a salt pan for natural evaporation;

(8) adding a flotation reagent (YC-8850 g/t crude ore) into a chemical-adding pulp-mixing stirring barrel, and fully stirring to obtain chemical-adding ore pulp;

(9) after adding the chemicals, feeding the ore pulp to flotation to obtain flotation concentrate ore pulp and flotation tailing ore pulp after flotation, feeding the flotation concentrate ore pulp to a crude potassium filter for filtering, and feeding the flotation tailing ore pulp to a tailing washing stirring barrel for washing;

(10) fresh water for flotation tailing washing (31 m)³Fresh water obtained by collecting, precipitating and clarifying various production sewage such as mechanical sealing water, cooling water, working platform flushing water and the like in a production workshop) is added into a tailing washing and stirring barrel to float tailings and oversize materials of a No. 2 vibrating screenWashing, and conveying the washed ore pulp to a tailing thickening tank for thickening;

(11) washed mixed tailing pulp (343 m)³H) thickening the tailings in a thickening tank, and then thickening the underflow in the thickening tank (127.5 m)³H) sending the mixture to a tailing filter for filtering, and overflowing mother liquor (280 m)³H) returning to a stock solution storage tank;

(12) filtering with tailing filter to obtain tailing filter cake (98t/h, mass content of main components is KCl 1.87%, MgCl)₂3.99%, NaCl 83.69%) and tailings mother liquor (65 m)³The mass content of main components is KCl 4.07 percent and MgCl₂19.41 percent of NaCl and 3.29 percent of NaCl), sending the tailings to a salt field tailing dam or an underground filling station, and returning the tailing mother liquor to a tailing thickening pool;

(13) filtering the flotation concentrate pulp by a crude potassium filter to obtain crude potassium (35t/h, the mass content of main components is KCl 81.91 percent, and MgCl)₂3.52%, NaCl 7.18%) and crude potassium mother liquor (58 m)³The mass content of main components is KCl 3.94 percent and MgCl₂19.97 percent of NaCl and 1.62 percent of NaCl), sending the crude potassium to a crude potassium washing and stirring barrel for washing, and sending the crude potassium mother liquor to a size mixing mother liquor storage tank;

(14) crude Potassium Wash fresh Water (7 m)³H, fresh water) and the mother liquor of refined potassium (6 m) obtained by subsequent filtration³The mass content of the main components is KCl 10.57 percent and MgCl₂2.43 percent of NaCl and 16.63 percent of NaCl) are added into a crude potassium washing and stirring barrel to wash the crude potassium, so as to obtain refined potassium pulp;

(15) sending the refined potassium ore slurry to a refined potassium filter for filtering to obtain refined potassium (28t/h, the mass content of the main components is KCl 96.83%, MgCl)₂0.20%, NaCl 0.72%) and refined potassium mother liquor (13 m)³The mass content of the main components is KCl 10.57 percent and MgCl₂2.43 percent of NaCl and 16.63 percent of NaCl, and the refined potassium is sent to a drying workshop for dehydration and drying to obtain a high-quality potassium chloride product (28t/h) with the concentration of 95 percent and the surplus refined potassium mother liquor (7 m)³And/h) returning to the decomposing crystallizer for decomposing and crystallizing the carnallite.

The mass content of the main component of the obtained potassium chloride product is that the KCl content reaches 96.83%, the yield is 28t/h, and the KCl recovery rate is 76.90%.

Example 2

(1) Will be provided withSome native carnallite (the mass content of main components is KCl 18.31%, MgCl)₂15.62 percent and 48.12 percent of NaCl) to be crushed to below 8mm, and the ore loading of the carnallite is 220 t/h;

(2) sending the carnallite ore crushed in the step (1) into a decomposing crystallizer through a rubber belt conveyor, and adding a slurry adjusting mother solution (262 m) into the cold decomposing crystallizer³The mass content of the main components is KCl 4.31 percent and MgCl₂17.85% NaCl 3.20%) and refined potassium mother liquor (8.8 m)³The mass content of the main components is KCl 11.36 percent and MgCl₂1.92 percent and NaCl 16.19 percent) carries out decomposition and crystallization on the carnallite to obtain decomposed crystallization underflow ore pulp and decomposed crystallization overflow;

(3) decomposing and crystallizing underflow ore pulp (378 m)³H) feeding to No. 1 vibrating screen for sieving (mesh diameter is 1mm), and adding decomposition mother liquor (64 m)³The mass content of the main components is KCl 3.85 percent and MgCl₂25.21 percent and NaCl 2.01 percent) as screening washing water, and oversize products (84t/h, the mass content of main components is KCl 5.26 percent and MgCl₂0.93 percent and NaCl 87.45 percent) is sent to a screening washing stirring barrel for washing, and pulp (394m below the screen)³H) sending the mixture to a No. 1 thickening tank for thickening;

(4) overflowing mother liquor (54 m) of a tailing thickening tank³The mass content of the main components is KCl 4.31 percent and MgCl₂17.85%, NaCl 3.20%) and fresh water (13 m)³Adding fresh water obtained by collecting, precipitating and clarifying various production sewage such as production workshop mechanical seal water, cooling water, working platform flushing water and the like into a screening, washing and stirring barrel to wash oversize products of a No. 1 vibrating screen to obtain washed ore pulp (112 m)³/h)；

(5) Conveying the washed ore pulp obtained by screening, washing and stirring barrels to a No. 2 vibrating screen (the diameter of a screen hole is 1mm) for screening, and simultaneously adding size mixing mother liquor (28 m)³The mass content of the main components is KCl 4.31 percent and MgCl₂17.85 percent and 3.20 percent of NaCl) are taken as screening flushing water, oversize products are sent to a tailing washing stirring barrel, and undersize ore pulp (94 m)³The mass content of the main components is KCl 4.31 percent and MgCl₂17.85 percent and 3.20 percent of NaCl) are returned to the decomposition crystallizer;

(6) overflow of decomposed crystals (5.5 m)³The mass content of the main components is KCl 3.85 percent and MgCl₂25.21 percent of NaCl 2.01 percent) is sent to a No. 2 thickening tank for thickening, and the underflow of the No. 2 thickening tank (0.90 m)³H) sending the mixture to a flotation dosing and pulp mixing stirring barrel, and overflowing the mixture (4.6 m)³The mass content of the main components is KCl 3.85 percent and MgCl₂25.21 percent and NaCl 2.01 percent) are sent to a stock solution storage tank or a chemical evaporation plant for forced evaporation and crystallization;

(7) no. 1 thickening tank underflow (293 m)³H) sending the mixture to a chemical adding and size mixing stirring barrel, and overflowing (101 m)³H) sending the slurry-mixing mother liquor to a slurry-mixing mother liquor storage tank or a chemical evaporation workshop for forced evaporation and crystallization;

(8) adding a flotation reagent (YC-8960 g/t crude ore) into a chemical-adding pulp-mixing stirring barrel, and fully stirring to obtain chemical-adding ore pulp;

(9) after adding the chemicals, feeding the ore pulp to flotation to obtain flotation concentrate ore pulp and flotation tailing ore pulp after flotation, feeding the flotation concentrate ore pulp to a crude potassium filter for filtering, and feeding the flotation tailing ore pulp to a tailing washing stirring barrel for washing;

(10) fresh water for flotation tailing washing (31 m)³Fresh water obtained by collecting, precipitating and clarifying various production sewage such as production workshop mechanical seal water, cooling water, working platform flushing water and the like) is added into a tailing washing and stirring barrel to wash flotation tailings and oversize products of a No. 2 vibrating screen, and the ore pulp after washing is sent to a tailing thickening tank for thickening;

(11) washed mixed tailing pulp (417 m)³H) thickening in a tailing thickening tank, and then thickening the underflow in the thickening tank (181.5 m)³H) sending to a tailing filter for filtering, and overflowing mother liquor (328 m)³H) returning to a stock solution storage tank;

(12) filtering with tailing filter to obtain tailing filter cake (140t/h, mass content of main components is KCl 1.96%, MgCl)₂2.83%, NaCl 87.60%) and tailings mother liquor (93 m)³The mass content of the main components is KCl 4.31 percent and MgCl₂17.85 percent of NaCl and 3.20 percent of NaCl), sending the tailings to a salt field tailing dam or an underground filling station, and returning the tailing mother liquor to a tailing thickening tank;

(13) the flotation concentrate ore pulp is filtered by a crude potassium filter to obtain crude potassium (45t/h, the mass content of main components is KCl 78.21%,MgCl₂2.97%, NaCl 9.81%) and crude potassium mother liquor (99 m)³The mass content of the main components is KCl 4.19 percent and MgCl₂19.74 percent of NaCl and 1.88 percent of NaCl), sending the crude potassium to a crude potassium washing and stirring barrel for washing, and sending the crude potassium mother liquor to a size mixing mother liquor storage tank;

(14) crude Potassium Wash fresh Water (12 m)³H, fresh water) and the refined potassium mother liquor (12 m) obtained by subsequent filtration³The mass content of the main components is KCl 11.36 percent and MgCl₂1.92 percent and NaCl 16.19 percent) are added into a crude potassium washing and stirring barrel to wash the crude potassium, so as to obtain refined potassium pulp;

(15) the fine potassium ore pulp is sent to a fine potassium filter for filtration to obtain fine potassium (33t/h, the mass content of the main components is KCl 96.71 percent, MgCl₂0.15%, NaCl 0.80%) and refined potassium mother liquor (20 m)³The mass content of the main components is KCl 11.36 percent and MgCl₂1.92 percent of NaCl 16.19 percent of potassium chloride, and refined potassium is sent to a drying workshop for dehydration and drying to obtain a high-quality potassium chloride product (33t/h) with the concentration of 95 percent and redundant refined potassium mother liquor (8 m)³And/h) returning to the decomposing crystallizer for decomposing and crystallizing the carnallite.

The mass content of the main component of the obtained potassium chloride product is that the KCl content reaches 96.71%, the yield is 33t/h, and the KCl recovery rate is 78.29%.

Example 3

(1) Mixing carnallite ore (KCl 15.49 wt% and MgCl as main components) in salt field₂17.21 percent and NaCl 41.94 percent) are conveyed into a decomposing crystallizer by a rubber belt conveyor, and the ore loading of the carnallite is 240 t/h;

(2) adding the prepared mother liquor (274 m) into the decomposition tank³The mass content of the main components is KCl 4.12 percent and MgCl₂20.74%, NaCl 2.25%) and refined potassium mother liquor (8 m)³The mass content of the main components is KCl 10.82 percent and MgCl₂3.25 percent and NaCl 16.35 percent) of the carnallite are decomposed and crystallized to obtain decomposed crystallization underflow pulp and decomposed crystallization overflow;

(3) decomposing the crystal underflow ore pulp (347 m)³H) sieving with No. 1 vibrating screen (mesh diameter 0.75mm), and adding decomposition mother liquor (95 m)³The mass content of the main components is KCl 3.53 percent and MgCl₂26.33% NaCl 1.28%) as sieve washWashing with water, sieving with screen (69t/h, mass content of main components KCl 4.15%, MgCl₂93.24 percent and NaCl 1.85 percent) are sent to a screening washing stirring barrel for washing, and pulp (403 m) below the screen is obtained³H) sending the mixture to a No. 1 thickening tank for thickening;

(4) overflowing mother liquor (46 m) of a tailing thickening tank³The mass content of the main components is KCl 4.12 percent and MgCl₂20.74%, NaCl 2.25%) and fresh water (10 m)³Adding fresh water obtained by collecting, precipitating and clarifying various production sewage such as production workshop mechanical seal water, cooling water, working platform flushing water and the like into a screening, washing and stirring barrel to wash oversize products of a No. 1 vibrating screen to obtain washed ore pulp (93 m)³/h)；

(5) The washed ore pulp obtained by the screening, washing and stirring barrel is sent to a No. 2 vibrating screen (the diameter of a screen hole is 0.75mm) for screening, and meanwhile, the size mixing mother liquor (28 m) is added³The mass content of the main components is KCl 4.12 percent and MgCl₂20.74 percent and NaCl 2.25 percent) as screening flushing water, and oversize products are sent to a tailing washing stirring barrel and undersize ore pulp (83 m)³The mass content of the main components is KCl 4.12 percent and MgCl₂20.74% and NaCl 2.25%) back to the decomposing crystallizer;

(6) overflow of decomposed crystals (19 m)³The mass content of the main components is KCl 3.53 percent and MgCl₂26.33 percent of NaCl and 1.28 percent of NaCl) are sent to a No. 2 thickening tank for thickening, and the underflow of the No. 2 thickening tank (0.75 m)³H) sending the mixture to a flotation dosing and pulp mixing stirring barrel, and overflowing the mixture (18 m)³The mass content of the main components is KCl 3.53 percent and MgCl₂26.33 percent of NaCl and 1.28 percent of NaCl) to a salt pan natural evaporation crystallization or size mixing mother liquor storage tank;

(7) no. 1 thickening tank bottom flow (243 m)³H) sending the mixture to a chemical adding and size mixing stirring barrel, and overflowing (160 m)³H) sending the salt pan to a natural evaporation crystallization or size mixing mother liquor storage tank;

(8) adding a flotation reagent (YC-8545 g/t raw ore) into a chemical-adding pulp-mixing stirring barrel, and fully stirring to obtain chemical-adding ore pulp;

(9) after adding the chemicals, feeding the ore pulp to flotation to obtain flotation concentrate ore pulp and flotation tailing ore pulp after flotation, feeding the flotation concentrate ore pulp to a crude potassium filter for filtering, and feeding the flotation tailing ore pulp to a tailing washing stirring barrel for washing;

(10) fresh water (30 m) for washing flotation tailings³Fresh water obtained by collecting, precipitating and clarifying various production sewage such as production workshop mechanical seal water, cooling water, working platform flushing water and the like) is added into a tailing washing and stirring barrel to wash flotation tailings and oversize products of a No. 2 vibrating screen, and the ore pulp after washing is sent to a tailing thickening tank for thickening;

(11) washed mixed tailing pulp (367 m)³H) thickening the tailings in a thickening tank, and then thickening the underflow of the thickening tank (147 m)³H) sending to a tailing filter for filtering, and overflowing mother liquor (295 m)³H) returning to a stock solution storage tank;

(12) filtering with tailing filter to obtain tailing filter cake (113t/h, mass content of main components is KCl 0.74%, MgCl)₂3.05%, NaCl 84.48%) and tailings mother liquor (75 m)³The mass content of the main components is KCl 4.17 percent and MgCl₂19.45 percent of NaCl and 3.35 percent of NaCl), sending the tailings to a salt field tailing dam or an underground filling station, and returning the tailing mother liquor to a tailing thickening tank;

(13) filtering the flotation concentrate pulp by a crude potassium filter to obtain crude potassium (40t/h, the mass content of main components is KCl 79.44 percent and MgCl)₂3.31%, NaCl 8.67%) and crude potassium mother liquor (81 m)³The mass content of the main components is KCl 3.95 percent and MgCl₂20.15 percent of NaCl and 1.33 percent of NaCl), sending the crude potassium to a crude potassium washing and stirring barrel for washing, and sending the crude potassium mother liquor to a size mixing mother liquor storage tank;

(14) crude Potassium Wash fresh Water (7 m)³H, fresh water) and the refined potassium mother liquor (7 m) obtained by subsequent filtration³The mass content of the main components is KCl 10.82 percent and MgCl₂2.25 percent of NaCl and 16.35 percent of NaCl) are added into a crude potassium washing and stirring barrel to wash the crude potassium, so as to obtain refined potassium pulp;

(15) sending the refined potassium ore slurry to a refined potassium filter for filtering to obtain refined potassium (32t/h, the mass content of the main components is KCl 95.68%, MgCl)₂0.30%, NaCl 0.85%) and refined potassium mother liquor (15 m)³The mass content of the main components is KCl 10.82 percent and MgCl₂2.25 percent of NaCl and 16.35 percent of NaCl), and the refined potassium is sent to a drying workshop for dehydration and drying to obtain a high-quality potassium chloride product (32t/h) with the concentration of 95 percent and the surplus potassium chloride productRefined potassium mother liquor (8 m)³And/h) returning to the decomposing crystallizer for decomposing and crystallizing the carnallite.

The mass content of the main component of the obtained potassium chloride product is that the KCl content reaches 95.68%, the yield is 32t/h, and the KCl recovery rate is 80.15%.