阅读说明：本技术 一种钾肥生产中水浴除尘废水的回收方法 (Method for recovering water bath dedusting wastewater in potash fertilizer production ) 是由 李小飞 田红斌 哈占方 岳宏伟 窦永钦 郝红军 张生太 孟浩 赵小刚 方敏 杨小 于 2019-10-17 设计创作，主要内容包括：本发明公开一种钾肥生产中水浴除尘废水的回收方法,其中,所述回收方法为：第一钾肥生产系统通过第一氯化钾生产工艺生产氯化钾,并通过水浴除尘器对所述氯化钾除尘,产生含氯化钾的废水,所述废水提供至第一钾肥生产系统的第一氯化钾生产工艺和/或第二钾肥生产系统的第二氯化钾生产工艺以回收利用。本发明提供的钾肥生产中水浴除尘废水的回收方法中,将第一钾肥生产系统产生的含氯化钾的废水提供至第一钾肥生产系统的第一氯化钾生产工艺和/或第二钾肥生产系统的第二氯化钾生产工艺,便于将其中的氯化钾和水资源进行回收利用,也可以减少添加的淡水量,从而减少对环境的污染,提高了物料的利用率。(The invention discloses a method for recovering water bath dedusting wastewater in potash fertilizer production, wherein the method comprises the following steps: the first potash fertilizer production system produces potassium chloride through a first potassium chloride production process, and removes dust from the potassium chloride through a water bath dust remover to produce wastewater containing potassium chloride, and the wastewater is supplied to the first potassium chloride production process of the first potash fertilizer production system and/or a second potassium chloride production process of the second potash fertilizer production system for recycling. In the method for recovering the water bath dedusting wastewater in the potash fertilizer production, the wastewater containing potassium chloride and generated by the first potash fertilizer production system is provided to the first potassium chloride production process of the first potash fertilizer production system and/or the second potassium chloride production process of the second potash fertilizer production system, so that the potassium chloride and water resources in the wastewater can be conveniently recycled, and the amount of added fresh water can be reduced, thereby reducing the pollution to the environment and improving the utilization rate of materials.)

1. A method for recovering water bath dedusting wastewater in potash fertilizer production is disclosed, wherein the method comprises the following steps: the first potash fertilizer production system (1) produces potassium chloride through a first potassium chloride production process (11), and removes dust from the potassium chloride through a water bath dust remover (12), so as to produce waste water containing potassium chloride, and the waste water is supplied to the first potassium chloride production process (11) of the first potash fertilizer production system (1) and/or a second potassium chloride production process (21) of the second potash fertilizer production system (2) for recycling.

2. The method for recovering the dust-removing wastewater in the potash fertilizer production according to claim 1, wherein the first potassium chloride production process (11) of the first potash fertilizer production system (1) is any one of a reverse flotation-cold crystallization process, a cold crystallization-direct flotation process, and a cold decomposition-direct flotation process.

3. The method for recovering the dust-removing wastewater in the potash fertilizer production according to claim 1, wherein the second potassium chloride production process (21) of the second potash fertilizer production system (2) is any one of a reverse flotation-cold crystallization process, a cold crystallization-positive flotation process, and a cold decomposition-positive flotation process.

4. The method for recovering the water bath dedusting wastewater in the potash fertilizer production according to claim 1, wherein a first potassium chloride production process (11) of the first potash fertilizer production system (1) is the same as a second potassium chloride production process (21) of the second potash fertilizer production system (2).

5. The method for recovering the dust-removing wastewater in the potash fertilizer production according to claim 1, wherein a first potassium chloride production process (11) of the first potash fertilizer production system (1) is different from a second potassium chloride production process (21) of the second potash fertilizer production system (2).

6. The method for recycling the dust-removing wastewater in the potash fertilizer production according to claim 3, wherein when the second potassium chloride production process (21) of the second potash fertilizer production system (2) is a reverse flotation-cold crystallization process, the reverse flotation-cold crystallization process is provided with a crystallizer (211), and the wastewater is provided to the crystallizer (211) for recycling.

7. The method for recovering the water bath dedusting wastewater in the potash fertilizer production according to claim 3, wherein when the second potassium chloride production process (21) of the second potassium fertilizer production system (2) is a reverse flotation-cold crystallization process, the reverse flotation-cold crystallization process is provided with a first repulping washing system (212), and the wastewater is provided to the first repulping washing system (212) for recycling.

8. The method for recovering the water bath dedusting wastewater in the potash fertilizer production according to claim 3, wherein when the second potassium chloride production process (21) of the second potash fertilizer production system (2) is a cold crystallization-direct flotation process, the cold crystallization-direct flotation process is provided with a second repulping washing system (213), and the wastewater is provided to the second repulping washing system (213) for recycling.

9. The method for recovering the dust removing wastewater in the potash fertilizer production according to claim 3, wherein when the second potassium chloride production process (21) of the second potash fertilizer production system (2) is a cold decomposition-direct flotation process, the cold decomposition-direct flotation process is provided with a cold decomposition system (214), and the wastewater is provided to the cold decomposition system (214) for recycling.

10. The method for recovering the water bath dedusting wastewater in the potash fertilizer production as recited in claim 1, wherein the water bath deduster (12) is a centrifugal water bath deduster.

Technical Field

The invention relates to the technical field of wastewater recovery, in particular to a method for recovering water bath dedusting wastewater in potash fertilizer production.

Background

In the production of potash fertilizers, no matter which production process is adopted, the dust remover is required to be used for removing dust of potash fertilizers such as potassium chloride and the like in the later period of the process, the dust removing equipment is various, and the water bath dust remover is widely applied to the advantages of high dust removing efficiency, wide application range, purification effect and difficulty in blocking.

However, the water bath dust remover has a defect that waste water with high concentration is generated, and the waste water in the water bath dust remover is discharged periodically after the water bath dust remover operates for a period of time; in chemical production, waste water is often subjected to simple treatment and then directly discharged into a designated pool to be naturally evaporated or directly discharged into the environment, so that the environment is greatly polluted, the waste of water resources is caused, and the waste water often contains substances such as potassium chloride and the like and is also wasted; if the part of waste water is further purified, the technical requirements on purification treatment equipment are high, and the treatment is difficult.

Disclosure of Invention

The invention aims to provide a method for recovering water bath dedusting wastewater in potash fertilizer production, which is used for solving the problems of environmental pollution, material waste and difficult purification treatment caused by direct discharge of the water bath dedusting wastewater in the prior art.

In order to achieve the above purpose, the invention provides the following technical scheme: a method for recovering water bath dedusting wastewater in potash fertilizer production comprises the following steps: the first potash fertilizer production system produces potassium chloride through a first potassium chloride production process, and removes dust from the potassium chloride through a water bath dust remover to produce wastewater containing potassium chloride, and the wastewater is supplied to the first potassium chloride production process of the first potash fertilizer production system and/or a second potassium chloride production process of the second potash fertilizer production system for recycling.

Further, the first potassium chloride production process of the first potash fertilizer production system is any one of a reverse flotation-cold crystallization process, a cold crystallization-direct flotation process and a cold decomposition-direct flotation process.

Further, the second potassium chloride production process of the second potassium fertilizer production system is any one of a reverse flotation-cold crystallization process, a cold crystallization-direct flotation process and a cold decomposition-direct flotation process.

Further, the first potassium chloride production process of the first potassium fertilizer production system is the same as the second potassium chloride production process of the second potassium fertilizer production system.

Further, a first potassium chloride production process of the first potassium fertilizer production system is different from a second potassium chloride production process of the second potassium fertilizer production system.

Further, when the second potassium chloride production process of the second potassium fertilizer production system is a reverse flotation-cold crystallization process, the reverse flotation-cold crystallization process is provided with a crystallizer, and the wastewater is provided to the crystallizer for recycling.

Further, when the second potassium chloride production process of the second potassium fertilizer production system is a reverse flotation-cold crystallization process, the reverse flotation-cold crystallization process is provided with a first repulping washing system, and the wastewater is provided to the first repulping washing system for recycling.

Further, when the second potassium chloride production process of the second potassium fertilizer production system is a cold crystallization-direct flotation process, the cold crystallization-direct flotation process is provided with a second repulping and washing system, and the wastewater is provided to the second repulping and washing system for recycling.

Further, when the second potassium chloride production process of the second potassium fertilizer production system is a cold decomposition-direct flotation process, the cold decomposition-direct flotation process is provided with a cold decomposition system, and the wastewater is provided to the cold decomposition system for recycling.

Further, the water bath dust remover is a centrifugal water bath dust remover.

Compared with the prior art, the method for recovering the water bath dedusting wastewater in the potash fertilizer production has the following advantages:

in the method for recovering the water bath dedusting wastewater in the potash fertilizer production, the wastewater containing potassium chloride and generated by the first potash fertilizer production system is provided to the first potassium chloride production process of the first potash fertilizer production system and/or the second potassium chloride production process of the second potash fertilizer production system, so that the potassium chloride and water resources in the wastewater can be conveniently recycled, and the amount of added fresh water can be reduced, thereby reducing the pollution to the environment and improving the utilization rate of materials.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for the purpose of illustrating preferred embodiments and are not to be construed as limiting the technical scope of the present invention. In the drawings:

FIG. 1 is a schematic flow chart of a method for recovering water bath dedusting wastewater in potash fertilizer production according to a preferred embodiment of the present invention;

FIG. 2 is a schematic flow chart of the method for recovering water-bath dust-removal wastewater in potash fertilizer production according to example 1 provided in the present invention;

FIG. 3 is a schematic flow chart of the method for recovering the water bath dedusting wastewater in the potash fertilizer production according to example 2 of the present invention;

FIG. 4 is a schematic flow chart of the method for recovering the water bath dedusting wastewater in the potash fertilizer production according to example 3 of the present invention;

FIG. 5 is a schematic flow chart of the method for recovering water-bath dedusting wastewater in potash fertilizer production according to example 4 of the present invention.

Reference numerals:

1-a first potash fertilizer production system, 11-a first potassium chloride production process,

12-a water bath dust remover, 2-a second potassium fertilizer production system,

21-second potassium chloride production process, 211-crystallizer,

212-first repulp wash system, 213-second repulp wash system,

214-cold decomposition system.

Detailed Description

The present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific examples described in the following embodiments of the present invention are merely illustrative of specific embodiments of the present invention and do not limit the scope of the invention.

The invention is further described with reference to the following figures and detailed description of embodiments.

As shown in FIG. 1, FIG. 1 is a schematic flow chart of a method for recovering water bath dedusting wastewater in potash fertilizer production according to a preferred embodiment of the present invention.

The invention provides a method for recovering water bath dedusting wastewater in potash fertilizer production, which comprises the following steps: the first potash fertilizer production system 1 produces potassium chloride through the first potassium chloride production process 11, and removes dust from the potassium chloride through the water bath dust collector 12 to produce wastewater containing potassium chloride, which is provided to the first potassium chloride production process 11 of the first potash fertilizer production system 1 and/or the second potassium chloride production process 21 of the second potash fertilizer production system 2 for recycling.

In the method for recovering the water bath dedusting wastewater in the potash fertilizer production, the wastewater containing potassium chloride and generated by the first potash fertilizer production system is provided to the first potassium chloride production process of the first potash fertilizer production system and/or the second potassium chloride production process of the second potash fertilizer production system, so that the potassium chloride and water resources in the wastewater can be conveniently recycled, and the amount of added fresh water can be reduced, thereby reducing the pollution to the environment and improving the utilization rate of materials.

In the application, the wastewater is the water bath dust removal wastewater, that is, the wastewater generated by the water bath dust remover 12 contains potassium chloride and the like, and potassium-containing dust generated in the potassium fertilizer production process.

Further, the first potassium chloride production process 11 of the first potash fertilizer production system 1 is any one of a reverse flotation-cold crystallization process, a cold crystallization-direct flotation process, and a cold decomposition-direct flotation process. The recovery method provided by the application is suitable for various potassium chloride production processes, and the generated wastewater can be recycled.

Carnallite (KCl MgCl)₂˙6H₂O) is a complex salt which can stably exist in a large temperature range (-21 ℃ to 167.65 ℃), and most of raw ores of a reverse flotation-cold crystallization process, a cold crystallization-positive flotation process and a cold decomposition-positive flotation process are carnallite ores.

The reverse flotation-cold crystallization process comprises the following steps: a relatively advanced process in large-scale production. When the potash fertilizer is produced, adding a flotation reagent into a saturated flotation medium in a flotation machine to selectively increase the hydrophobicity of the surface of sodium chloride without increasing the hydrophobicity of carnallite, wherein the sodium chloride is adhered to foam in the flotation machine and is separated along with the foam, the carnallite is left in ore pulp, and high-grade low-sodium carnallite is obtained after dehalogenation; and (2) feeding the low-sodium carnallite into a crystallizer, adding water or circulating mother liquor to carry out decomposition crystallization, controlling the decomposition crystallization to ensure that potassium chloride in the solution is supersaturated, the potassium chloride crystal particles grow, and preparing the finished product potassium chloride through the working procedures of a filtering system, a repulping washing system and the like, wherein the produced potassium chloride product has high content, high particle size and low moisture.

The cold crystallization-direct flotation process comprises the following steps: compared with the traditional process in large-scale production. During production, carnallite and circulating mother liquor are decomposed and crystallized in a crystallizer, carnallite is dissolved in the circulating mother liquor to form supersaturated solution of potassium chloride, potassium chloride crystal particles grow at normal temperature by utilizing the supersaturation degree of a carnallite decomposition system, coarse potassium crystals with larger particles are separated out from the supersaturated solution to obtain slurry containing the coarse potassium, the slurry enters a flotation system to carry out a positive flotation process, and the fine potassium slurry obtained by flotation is subjected to solid-liquid separation and drying processes by a filtering system, a repulping washing system, a centrifugal machine to obtain a finished product of potassium chloride, so that the energy consumption is low, and the particle size is good.

A cold decomposition-direct flotation process; carnallite is decomposed in a cold decomposition system under the action of fresh water and slurry mixing mother liquor, magnesium chloride solid phase in the carnallite is converted into liquid phase to the maximum extent to obtain slurry, the slurry enters a flotation system for a direct flotation process in a medium of high-magnesium mother liquor, and the refined potassium slurry obtained by flotation is processed by a filtering system and a repulping and washing system to obtain a finished product potassium chloride, so that the process is simple and the conditions are mild.

Further, the second potassium chloride production process 21 of the second potassium fertilizer production system 2 is any one of a reverse flotation-cold crystallization process, a cold crystallization-direct flotation process, and a cold decomposition-direct flotation process. The recovery method provided by the application is suitable for various potassium chloride production processes, and is wide in application range.

Further, the first potassium chloride production process 11 of the first potassium fertilizer production system 1 is the same as the second potassium chloride production process 21 of the second potassium fertilizer production system 2. In the same potassium chloride production process, the water bath dedusting wastewater can be recycled, and the wastewater discharge is reduced.

Further, the first potassium chloride production process 11 of the first potassium fertilizer production system 1 is different from the second potassium chloride production process 21 of the second potassium fertilizer production system 2. Even different potassium chloride production processes, the water bath dedusting wastewater can be recycled without process limitation.

Further, the water bath dust collector 12 is a centrifugal water bath dust collector. The efficiency is higher when the same energy is consumed; the dust removal efficiency for purifying high specific resistance, high humidity, high temperature, inflammable and explosive dust-containing gas is high; the dust particles of the dust-containing gas can be removed, and simultaneously, the water vapor and certain toxic and harmful gas pollutants in the gas can be removed; the water bath dust collector is internally provided with a small gap and a small orifice, so that the flue gas with higher dust concentration can be treated without blockage.