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WO2021248774A1 - Dispositif de cristallisation de nitrate de potassium de type à circulation - Google Patents

Dispositif de cristallisation de nitrate de potassium de type à circulation Download PDF

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Publication number
WO2021248774A1
WO2021248774A1 PCT/CN2020/123678 CN2020123678W WO2021248774A1 WO 2021248774 A1 WO2021248774 A1 WO 2021248774A1 CN 2020123678 W CN2020123678 W CN 2020123678W WO 2021248774 A1 WO2021248774 A1 WO 2021248774A1
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WO
WIPO (PCT)
Prior art keywords
circulating
pipe
cylinder
side wall
tube
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2020/123678
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English (en)
Chinese (zh)
Inventor
赵晨
熊云生
田野
梁廷刚
李武平
孙红喜
赵遵闻
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Golden Potassium Technology Co Ltd
Original Assignee
Golden Potassium Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Golden Potassium Technology Co Ltd filed Critical Golden Potassium Technology Co Ltd
Publication of WO2021248774A1 publication Critical patent/WO2021248774A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D9/00—Crystallisation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D9/00—Crystallisation
    • B01D9/02—Crystallisation from solutions
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
    • C01D9/00—Nitrates of sodium, potassium or alkali metals in general
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
    • C01D9/00—Nitrates of sodium, potassium or alkali metals in general
    • C01D9/18—Preparation in the form of shaped products, e.g. granules

Definitions

  • the invention relates to the technical field of potassium nitrate preparation, in particular to a circulating potassium nitrate crystallizer.
  • Potassium nitrate is a colorless transparent rhombic or rhombic crystal white powder, easily soluble in water, insoluble in ethanol, and not easy to deliquesce in the air. The product is a strong oxidant and can burn and explode in contact with organic matter. Potassium nitrate is widely used in the agricultural market. Potassium nitrate is a chlorine-free potassium and nitrogen compound fertilizer. The total content of phytonutrient potassium and nitrogen can reach about 60%, and it has good physical and chemical properties. Potassium nitrate applied to tobacco has high fertilizer efficiency, is easy to absorb, promotes the early emergence of seedlings, increases tobacco yield, and improves tobacco quality.
  • the Oslo evaporative crystallizer is a kind of mother liquor circulating continuous crystallizer.
  • the operating material liquid is added to the circulating tube, mixed with the circulating mother liquid in the tube, and sent to the heating chamber by the pump.
  • the heated solution evaporates in the evaporation chamber and reaches supersaturation, and enters the crystal fluidized bed below the evaporation chamber through the central tube.
  • the supersaturated solute in the solution deposits on the surface of the suspended particles, causing the crystals to grow.
  • the crystal fluidized bed performs hydraulic classification of the particles, with large particles on the bottom and small particles on the top, and the crystalline product with a relatively uniform particle size is discharged from the bottom of the fluidized bed.
  • the fine particles in the fluidized bed flow into the circulation pipe with the mother liquor, and the tiny crystals are dissolved when reheated. If the heating chamber of the Oslo evaporative crystallizer is replaced by a cooling chamber and the evaporative chamber and the like are removed, the Oslo cooling crystallizer is constructed.
  • the purpose of the present invention is to provide a circulating potassium nitrate crystallization device to solve the problem that the existing Oslo cooling crystallizer proposed in the background art is used for potassium nitrate crystallization, which easily blocks the discharge port and cannot discharge the material.
  • a circulating potassium nitrate crystallization device which is characterized in that it comprises a crystallizer cylinder, an overflow box, a circulating pipe, a first circulating pump, a heat exchanger, a central pipe, and a circulating flushing pipe.
  • the upper end of the crystallizer cylinder is open,
  • the crystallizer cylinder includes an upper cylindrical part, a conical part, a lower cylindrical part, and an arc-shaped cylinder bottom in sequence from top to bottom.
  • the arc-shaped cylinder bottom is provided with a discharge tube, and the center tube It is set in the middle of the mold cylinder and inserted straight into the upper end of the bottom of the arc-shaped cylinder from the upper end of the mold cylinder.
  • the lower end of the center tube is set as a conical tube whose diameter gradually expands downwards.
  • the overflow box is set in the mold On the outer side wall of the upper end of the cylinder, the inner cavity is communicated with the inner cavity of the crystallizer cylinder, and the bottom is provided with an overflow port.
  • the first circulation pump and the heat exchanger are both arranged on the outside of the crystallizer cylinder, and the circulation pipe is provided with multiple sections. , The overflow box, the first circulating pump, the heat exchanger, and the central pipe are connected in sequence.
  • the circulating punching pipe is provided with a number of pieces, which are evenly distributed around the outer wall of the mold cylinder.
  • the upper end of the circulating punching pipe The lower end of the circulation punch pipe is inserted into the lower cylindrical portion tangentially from the outer side wall of the lower cylindrical portion from the outer side wall of the middle portion of the cone portion and sealedly connected.
  • Circulating pump is used to pump out the mother liquor from the cone part, and then rush into the lower cylinder part from the tangential direction of the lower cylinder part, so that the mother liquor at the lower end of the mold cylinder produces a rotating vortex, which drives the flow of the crystal grains at the bottom of the arc-shaped cylinder to prevent discharge The tube is clogged.
  • the diameter of the circulating flushing pipe is set to 80-100 mm.
  • crystallizer cylinder overflow box, central pipe, circulation pipe, and circulation flushing pipe are all made of 316 stainless steel.
  • the heat exchanger adopts a tube-and-tube heat exchanger.
  • the discharging pipe is provided with two pieces, and they are arranged obliquely at an angle of 30 degrees to the horizontal plane.
  • first support rods uniformly distributed on the circumference
  • second support rods uniformly distributed on the circumference
  • the motor of the first circulating pump adopts an adjustable motor, and the flow rate of the first circulating pump is adjusted by adjusting the rotation speed of the motor, thereby adjusting the crystal grain size in the circulating mother liquor and the number of crystal grains discharged from the discharge pipe.
  • the present invention has the following beneficial effects: 1) adopting a mother liquor circulating continuous crystallization structure, so that potassium nitrate can be continuously and uninterruptedly crystallized and discharged, which greatly improves production efficiency; 2) adopting a plurality of uniformly distributed in a circle
  • the circulating flushing tube makes the crystal liquid at the bottom of the crystallizer rotate, which can effectively prevent the accumulation of crystal grains from clogging the discharge pipe and ensure smooth discharge; 3)
  • the bottom of the crystallizer cylinder is set to an arc-shaped cylinder bottom, which improves the liquid crystal
  • the flow state in the crystallizer prevents the formation of dead zones to accumulate crystal grains.
  • Figure 1 is a schematic structural diagram of an embodiment of the present invention
  • Figure 2 is a schematic top view of the structure of an embodiment of the present invention.
  • FIG. 3 is a schematic diagram of the distribution structure of a multi-person circulation flushing pipe according to an embodiment of the present invention.
  • Mold cylinder 101, upper cylindrical part, 102, conical part, 103, lower cylindrical part, 104, arc-shaped cylinder bottom, 105, first support rod, 106, second support rod, 107 , Discharge pipe, 2, overflow box, 201, overflow port, 3, circulation pipe 1, 4, first circulation pump, 5, circulation pipe 2, 6, heat exchanger, 7, circulation pipe 3, 8. Central tube, 9, circulation flushing tube, 901, second circulation pump.
  • the embodiment of the present invention includes a crystallizer cylinder 1, an overflow box 2, a circulating pipe, a first circulating pump 4, a heat exchanger 6, a central pipe 8, and a circulating flushing pipe 9.
  • the upper end of the mold cylinder 1 is open for mother liquor.
  • the mold cylinder 1 includes an upper cylindrical portion 101, a cone portion 102, a lower cylindrical portion 103, an arc-shaped barrel bottom 104, and an arc-shaped barrel from top to bottom.
  • the bottom 104 is provided with a discharging tube 107, and the discharging tube 107 is provided with two pieces, which are inclined at an angle of 30 degrees with the horizontal plane.
  • the central tube 8 is set in the middle of the mold cylinder 1, and is inserted straight into the upper end of the arc-shaped cylinder bottom 104 from the upper end of the mold cylinder 1. Between the inner side wall of the part 101 and the outer side wall of the central tube 8 are provided a plurality of first support rods 105 uniformly distributed on the circumference. The pieces are second support rods 106 evenly distributed around the circumference.
  • the overflow box 2 is arranged on the outer side wall of the upper end of the crystallizer cylinder 1, the inner cavity is communicated with the inner cavity of the crystallizer cylinder 1, and an overflow port 201 is provided at the bottom.
  • the first circulating pump 4 and the heat exchanger 6 are both arranged on the outside of the crystallizer cylinder 1.
  • the heat exchanger 6 is a tubular heat exchanger with a water inlet at the upper end and a water outlet at the lower end.
  • the mother liquor flows from bottom to top in the tube, and the cold water flows from top to bottom on the outside of the tube, cold and hot convection, so that the mother liquid quickly cools down to the potassium nitrate saturated solution;
  • the motor of the first circulating pump 4 adopts an adjustable motor, and the motor is adjusted.
  • the rotation speed is used to adjust the flow rate of the first circulating pump 4, thereby adjusting the crystal grain size in the circulating mother liquor and the number of crystal grains discharged from the discharge pipe.
  • the circulation pipe is equipped with circulation pipe 1 3, circulation pipe 2 5, circulation pipe 3 7, overflow box 2, circulation pipe 1 3, first circulation pump 4, circulation pipe 2 5, heat exchanger 6, circulation pipe 3 7, and
  • the central pipes are connected in a sealed manner.
  • circulating punching pipes 9 arranged uniformly around the outer side wall of the mold cylinder 1.
  • the upper end of the circulating punching pipe 9 is radially inserted into the cone portion 102 from the outer side wall of the middle of the cone portion 102 and connected in a sealed manner.
  • the circulating punching pipe 9 The lower end is tangentially inserted into the lower cylindrical part 103 from the outer wall circumference of the lower part of the lower cylindrical part 103 and connected in a sealed manner.
  • the cylindrical part 103 punches into the lower cylindrical part 103 in a tangential direction, so that the mother liquor at the lower end of the mold cylinder 1 generates a swirling vortex, which drives the crystal grains at the bottom 104 of the arc-shaped cylinder to flow, preventing the crystal grains from clogging the discharge tube 107 and failing to discharge the material. .
  • the diameter of the circulating punch 9 is set to 80-100 mm.
  • the mold cylinder 1, the overflow box 2, the central pipe 8, the circulating pipe one 3, the circulating pipe two 5, the circulating pipe three 7, and the circulating punching pipe 9 are all made of 316 stainless steel.
  • the working mode of the present invention the mother liquor of 80 degrees is continuously added into the crystallizer cylinder 1, when the liquid level of the mother liquor exceeds the height of the overflow at the bottom of the overflow tank 2, the mother liquor will flow into the circulation pipe 3 from the overflow and start In the first circulation pump 4, the mother liquor enters the heat exchanger 6, and the mother liquor from the heat exchanger 6 is cooled to below 35 degrees, and then enters the central pipe 8, where potassium nitrate crystals are precipitated in the central pipe, and finally from the cone at the lower end of the central pipe 8.
  • the nozzle of the shaped pipe flows into the bottom of the arc-shaped cylinder and discharges the material from the discharge port.
  • a plurality of second circulating pumps 901 are activated to make the mother liquor in the cone part 102 enter the lower cylinder tangentially from the circumference of the lower cylindrical part 103 through the circulating punching pipe.
  • the lower end of the crystallizer cylinder 1 causes the mother liquor to generate a swirling vortex, which drives the crystal grains at the bottom 104 of the arc-shaped cylinder to flow, thereby preventing the crystal grains from clogging the discharge pipe 107 and ensuring smooth discharge.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Agronomy & Crop Science (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

Dispositif de cristallisation de nitrate de potassium de type à circulation, comprenant un réservoir de cristallisoir (1), une boîte de trop-plein (2), des tuyaux de circulation (3, 5, 7), une première pompe de circulation (4), un échangeur de chaleur (6), un tuyau central (8) et des tuyaux de rinçage en circulation (9). Le tuyau central (8) est disposé au milieu du réservoir de cristallisoir (1), et la boîte de trop-plein (2) est disposée sur la paroi latérale externe d'une extrémité supérieure du réservoir de cristallisoir (1). Les tuyaux de circulation (3, 5, 7) relient de manière séquentielle la boîte de trop-plein (2), la première pompe de circulation (4), l'échangeur de chaleur (6) et le tuyau central (8) de manière étanche. Plusieurs tuyaux de rinçage en circulation (9), sont répartis de manière régulière autour de la paroi latérale externe du réservoir de cristallisoir (1) de manière circonférentielle. Les extrémités supérieures des tuyaux de rinçage en circulation (9) sont insérées dans une partie conique (102) dans la direction radiale à partir de la paroi latérale externe du milieu de la partie conique (102) et sont reliées de manière étanche, et les extrémités inférieures du tuyau de rinçage en circulation (9) sont insérées tangentiellement dans une partie cylindrique inférieure (103) à partir de la circonférence de la paroi latérale externe d'une partie inférieure de la partie cylindrique inférieure (103) et sont reliées de manière étanche. Une seconde pompe de circulation (901) est disposée au milieu du tuyau de rinçage en circulation (9). Une structure de cristallisation continue par circulation de liqueur mère est utilisée, ce qui améliore considérablement l'efficacité de production. Une pluralité de tuyaux de rinçage en circulation (9) qui sont répartis de manière circonférentielle et uniforme sont utilisés pour permettre à un liquide cristallin au fond du cristallisoir de tourner, de sorte à empêcher efficacement que des grains cristallins s'accumulent et bloquent un tuyau d'évacuation, et une évacuation régulière est ainsi garantie.
PCT/CN2020/123678 2020-06-12 2020-10-26 Dispositif de cristallisation de nitrate de potassium de type à circulation Ceased WO2021248774A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202021080598.7U CN212504022U (zh) 2020-06-12 2020-06-12 一种循环式硝酸钾结晶装置
CN202021080598.7 2020-06-12

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114275837A (zh) * 2021-12-28 2022-04-05 江苏卓生源环保科技有限公司 一种冷冻结晶处理系统
CN114984609A (zh) * 2022-06-15 2022-09-02 朱虹静 一种硝酸钠结晶系统
CN115920441A (zh) * 2022-12-26 2023-04-07 安徽海华科技集团有限公司 一种连续结晶器旋转进料装置
CN117146483A (zh) * 2023-09-06 2023-12-01 内蒙古伊东集团东兴化工有限责任公司 一种取代膜法除硝冷冻机组的换热装置及换热方法
CN117299002A (zh) * 2023-11-29 2023-12-29 崇义绿冶新能源有限公司 一种碳酸锂制备用碳酸氢锂热解装置
CN117462989A (zh) * 2023-12-28 2024-01-30 山西铱倍力科技有限公司 一种氯铱酸生产用结晶设备
CN119075362A (zh) * 2024-11-05 2024-12-06 山东彩客东奥化学有限公司 一种对硝基甲苯的连续结晶装置
CN119367803A (zh) * 2024-12-26 2025-01-28 江西巍华化学有限公司 一种熔融结晶塔及结晶方法
CN119771010A (zh) * 2024-11-27 2025-04-08 湖北鄂中生态农业科技有限公司 一种微波加热辅助结晶水溶肥的连续结晶器

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115193088A (zh) * 2021-04-08 2022-10-18 长沙鑫本助剂有限公司 一种硝酸钾连续结晶装置及其操作工艺

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EP0923969A1 (fr) * 1997-12-18 1999-06-23 Niro Process Technology B.V. Système et méthode de cryoconcentration de substances
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CN108057258A (zh) * 2018-01-18 2018-05-22 江西金利达钾业有限责任公司 一种硝酸钾喷雾结晶器
CN108083299A (zh) * 2018-01-18 2018-05-29 江西金利达钾业有限责任公司 一种硝酸钾结晶生产系统
CN207493260U (zh) * 2017-10-18 2018-06-15 天津华景化工新技术开发有限公司 一种用于硝酸盐生产的结晶器

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4288285A (en) * 1980-07-28 1981-09-08 Evaporator Technology Corporation Apparatus for forming a vortex
EP0923969A1 (fr) * 1997-12-18 1999-06-23 Niro Process Technology B.V. Système et méthode de cryoconcentration de substances
CN103083947A (zh) * 2011-11-02 2013-05-08 上海远跃制药机械股份有限公司 轻重油水分离器
CN105289037A (zh) * 2015-11-11 2016-02-03 广东鑫国泰科技有限公司 氯酸钠结晶器
CN207493260U (zh) * 2017-10-18 2018-06-15 天津华景化工新技术开发有限公司 一种用于硝酸盐生产的结晶器
CN108057258A (zh) * 2018-01-18 2018-05-22 江西金利达钾业有限责任公司 一种硝酸钾喷雾结晶器
CN108083299A (zh) * 2018-01-18 2018-05-29 江西金利达钾业有限责任公司 一种硝酸钾结晶生产系统

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114275837A (zh) * 2021-12-28 2022-04-05 江苏卓生源环保科技有限公司 一种冷冻结晶处理系统
CN114984609A (zh) * 2022-06-15 2022-09-02 朱虹静 一种硝酸钠结晶系统
CN115920441A (zh) * 2022-12-26 2023-04-07 安徽海华科技集团有限公司 一种连续结晶器旋转进料装置
CN115920441B (zh) * 2022-12-26 2025-09-16 安徽海华科技集团有限公司 一种连续结晶器旋转进料装置
CN117146483B (zh) * 2023-09-06 2024-03-26 内蒙古伊东集团东兴化工有限责任公司 一种取代膜法除硝冷冻机组的换热装置及换热方法
CN117146483A (zh) * 2023-09-06 2023-12-01 内蒙古伊东集团东兴化工有限责任公司 一种取代膜法除硝冷冻机组的换热装置及换热方法
CN117299002A (zh) * 2023-11-29 2023-12-29 崇义绿冶新能源有限公司 一种碳酸锂制备用碳酸氢锂热解装置
CN117299002B (zh) * 2023-11-29 2024-03-19 崇义绿冶新能源有限公司 一种碳酸锂制备用碳酸氢锂热解装置
CN117462989B (zh) * 2023-12-28 2024-03-01 山西铱倍力科技有限公司 一种氯铱酸生产用结晶设备
CN117462989A (zh) * 2023-12-28 2024-01-30 山西铱倍力科技有限公司 一种氯铱酸生产用结晶设备
CN119075362A (zh) * 2024-11-05 2024-12-06 山东彩客东奥化学有限公司 一种对硝基甲苯的连续结晶装置
CN119771010A (zh) * 2024-11-27 2025-04-08 湖北鄂中生态农业科技有限公司 一种微波加热辅助结晶水溶肥的连续结晶器
CN119367803A (zh) * 2024-12-26 2025-01-28 江西巍华化学有限公司 一种熔融结晶塔及结晶方法

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