Wet-process phosphoric acid purification equipment

Abstract

The utility model discloses wet-process phosphoric acid purification equipment, which relates to the technical field of phosphoric acid production, and particularly comprises an adsorption tank, the top of the adsorption tank is provided with a raw material discharge port and a flushing substance filling port, the bottom of the adsorption tank is provided with a raw material filling port and a flushing substance discharge port, and the adsorption tank is filled with a resin column used for adsorbing organic substances in raw materials; the heat exchanger is connected in series with the flushing matter discharge port and is used for cooling the discharge of the flushing matter discharge port; according to the wet-process phosphoric acid purification equipment, the resin column is used as an adsorption medium, the adsorption effect of the resin column is used for adsorbing and decolorizing a product, the resin column is regenerated in a flushing mode, maintenance is easy, the use cost is low, sodium hydroxide is not needed in the regeneration process, and the product is prevented from being polluted by sodium ions.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of phosphoric acid production, more particularly to a wet-process phosphoric acid purification equipment. BACKGROUND

[0002] The purified phosphoric acid obtained in the back extraction process of the solvent extraction method for preparing wet-process purified phosphoric acid contains a small amount of solvent and other organic substances, and appears brownish yellow, so it needs to be analyzed and decolorized, on the one hand to recover the extractant (methyl isobutyl ketone, abbreviated as MIBK), and on the other hand to remove organic substances, so that the product colority meets the standard.

[0003] The existing process first uses a graphite rectifying tower to resolve the purified phosphoric acid, separates and recovers most of the organic solvents (i.e. extractants) in the acid, and then uses the adsorption of activated carbon in a decolorizing tower to remove the remaining organic substances in the phosphoric acid. This process has the problems of high investment cost of graphite tower equipment, consumption of a large amount of steam during operation, complex maintenance and repair of graphite equipment, long regeneration process and long regeneration cycle of activated carbon in the decolorizing tower, use of sodium hydroxide during regeneration, which causes the product to be easily contaminated by sodium ions, and high equipment maintenance cost.

[0004] In summary, how to provide a solution to the problems of high maintenance cost, long regeneration cycle and sodium ion contamination of the product of the wet-process phosphoric acid purification equipment is a problem that needs to be solved by the technical personnel in the field. UTILITY MODEL CONTENTS

[0005] Therefore, the utility model aims to provide a wet-process phosphoric acid purification equipment, which uses a resin column as an adsorption medium, uses the adsorption of the resin column to adsorb and decolorize the product, and regenerates the resin column in a flushing manner, so that the maintenance is simple, the use cost is low, and during the regeneration process, sodium hydroxide is not needed, which avoids the contamination of the product by sodium ions.

[0006] In order to achieve the above-mentioned purpose, the utility model provides the following technical scheme:

[0007] A wet-process phosphoric acid purification equipment, comprising:

[0008] An adsorption tank, which is provided at the top with a raw material discharge port and a flushing material filling port, and is provided at the bottom with a raw material filling port and a flushing material discharge port, and is filled with a resin column for adsorbing organic substances in the raw material;

[0009] A heat exchanger, which is connected in series to the flushing material discharge port for cooling the discharge of the flushing material discharge port.

[0010] Preferably, the adsorption tank is N groups, N ≥ 3, N is a positive integer, and the N groups of adsorption tanks are arranged in a ring-shaped series connection, and a first stop valve is arranged in the pipeline in series connection;

[0011] The raw material filling port of each adsorption tank is communicated with a raw material filling main pipeline, and a second stop valve is arranged between the raw material filling port and the raw material filling main pipeline;

[0012] The raw material discharge port of each adsorption tank is communicated with a buffer tank for storing the produced raw material, and a third stop valve is arranged between the raw material discharge port and the buffer tank.

[0013] Preferably, the flushing material discharge port of each adsorption tank is communicated with the heat exchanger, and a fourth stop valve is arranged between the flushing material discharge port and the heat exchanger;

[0014] The flushing material filling port of each adsorption tank is communicated with a flushing pipeline for supplying flushing material, and a stop valve is arranged between the flushing material filling port and the flushing pipeline.

[0015] Preferably, the flushing material filling port comprises a gas filling port and a flushing liquid filling port;

[0016] The gas filling port of each adsorption tank is respectively communicated with a gas main pipeline for supplying a gas source, and a fifth stop valve is arranged between the gas filling port and the gas main pipeline;

[0017] The flushing liquid filling port of each adsorption tank is communicated with a flushing liquid main pipeline for supplying flushing liquid, and a sixth stop valve is arranged between the flushing liquid filling port and the flushing liquid main pipeline.

[0018] Preferably, the flushing material filling port is respectively communicated with the gas main pipeline for supplying a gas source and the flushing liquid main pipeline for supplying flushing liquid through a reversing valve.

[0019] Preferably, the inlet end of the gas main pipeline is communicated with a steam pipeline and a compressed air pipeline in parallel, and a seventh stop valve is arranged between the gas main pipeline and the steam pipeline and the compressed air pipeline.

[0020] Preferably, the inlet end of the flushing liquid main pipeline is communicated with a cold water pipeline and a hot water pipeline in parallel, and an eighth stop valve is arranged between the flushing liquid main pipeline and the cold water pipeline and the hot water pipeline.

[0021] Preferably, the outlet end of the heat exchanger is provided with a phase separation tank for separating the discharge of the heat exchanger.

[0022] Compared with the prior art, the wet-process phosphoric acid purification equipment has at least the following beneficial effects:

[0023] The resin column is used as the adsorption material, the organic matter in the phosphoric acid is adsorbed by the pore diameter in the resin column, and then separation and decolorization are realized, the resin column can be regenerated, the production cost can be effectively reduced, and compared with the traditional graphite rectifying column purification mode, the resin column does not need to introduce sodium hydroxide during regeneration, so that the product is prevented from being polluted by sodium ions.

[0024] Meanwhile, the flushing material filling port and the flushing material discharge port are integrated in the adsorption tank, the resin column can be regenerated by flushing, the structure of the heat exchanger is increased, the organic matter flushed out can be collected after cooling, the recovery rate of the organic matter is improved, and the emission is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the drawings needed to be used in the following embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are only embodiments of the present application, and other drawings can be obtained by the provided drawings without creative labor for those skilled in the art.

[0026] Figure 1 The schematic diagram of the wet-process phosphoric acid purification equipment provided by the present application is shown in the figure.

[0027] Figure 2 The schematic diagram of another embodiment of the wet-process phosphoric acid purification equipment provided by the present application is shown in the figure.

[0028] Figure 3 The flowchart of the equipment regeneration method provided by the present application is shown in the figure.

[0029] Figure 4 The flowchart of the use method provided by the present application is shown in the figure.

[0030] In the figure:

[0031] 1, adsorption tank; 11, raw material filling port; 12, gas filling port; 13, flushing liquid filling port; 14, raw material discharge port; 15, flushing material discharge port;

[0032] 1a, first adsorption tank; 1b, second adsorption tank; 1c, third adsorption tank;

[0033] 2, buffer tank; 3, heat exchanger; 4, phase separation tank; 5, solvent recovery tank; 6, raw material filling main pipeline; 7, gas main pipeline; 8, flushing liquid main pipeline;

[0034] 9a, first stop valve; 9b, second stop valve; 9c, third stop valve; 9d, fourth stop valve; 9e, fifth stop valve; 9f, sixth stop valve; 9g, seventh stop valve; 9h, eighth stop valve. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model.

[0036] The core of the utility model provides a kind of wet-process phosphoric acid purification equipment, utilize resin column as adsorption medium, two processes of resolution and adsorption decolorization are combined into one, utilize the adsorption of resin column, adsorption decolorization is carried out to product, and resin column is regenerated in the way of flushing, maintenance is simple, use cost is lower, and in the regeneration process, sodium hydroxide is not needed to be used, avoid product to be polluted by sodium ion.

[0037] Please refer to Figure 1 A kind of wet-process phosphoric acid purification equipment, comprising:

[0038] Adsorption tank 1, its top is provided with raw material discharge port 14 and flushing material filling port, bottom is provided with raw material filling port 11 and flushing material discharge port 15, adsorption tank 1 is filled with resin column, for adsorbing organic matter in raw material;

[0039] Heat exchanger 3, it is connected in series in flushing material discharge port 15, for the cooling of the discharge of flushing material discharge port 15.

[0040] The way of filling resin column in adsorption tank 1 is adopted, the adsorption of organic matter in phosphoric acid is carried out by the adsorption of macropore in resin column, and the production cost is reduced;Moreover, the regeneration of resin column is carried out in the way of flushing, and the regeneration process is simple, and the regeneration cycle is short, and new metal ion is not needed to be introduced in the regeneration process, to avoid secondary pollution to finished product acid.

[0041] At the same time, adsorption tank 1 is provided with raw material filling port 11, raw material discharge port 14, flushing material filling port and flushing material discharge port 15, flushing material filling port and flushing material discharge port 15 are closed, normal production operation can be carried out, i.e. raw material such as phosphoric acid containing organic matter is injected from raw material filling port 11 at the bottom of adsorption tank 1, gradually floods resin column in adsorption tank 1, and then resin column adsorbs organic matter in raw material, and the adsorbed raw material is discharged from raw material discharge port 14 at the top of adsorption tank 1;

[0042] When the raw material filling port 11 and the raw material discharge port 14 are closed, the flushing material is filled into the flushing material filling port at the top of the adsorption tank 1, and the flushing material is flushed from top to bottom of the resin column. During the process, the shape of the adsorption tank 1 does not need to be converted, so the flushing operation is relatively simple. Compared with the traditional graphite rectifying tower and activated carbon adsorption, the production cost is small and the regeneration cycle is short, which is beneficial to reduce the overall production efficiency and production cost.

[0043] Moreover, the heat exchanger 3 is connected in series downstream of the flushing material discharge port 15, which can cool or liquefy the waste generated by flushing, promote the liquefaction and precipitation of organic substances in the waste, facilitate collection, reduce emissions, and contribute to environmental protection.

[0044] In some embodiments, the adsorption tank 1 is N groups, N≥3, N is a positive integer, and the N groups of adsorption tanks 1 are arranged in a ring shape in series, and the first stop valve 9a is arranged in the pipeline in series.

[0045] The raw material filling port 11 of all the adsorption tanks 1 is communicated with the raw material filling main pipeline 6, and the second stop valve 9b is arranged between the raw material filling port 11 and the raw material filling main pipeline 6.

[0046] The raw material discharge port 14 of all the adsorption tanks 1 is communicated with the buffer tank 2 for storing the raw material, and the third stop valve 9c is arranged between the raw material discharge port 14 and the buffer tank 2.

[0047] As shown in Figure 2 , N groups of adsorption tanks 1 are used in combination, such as the first adsorption tank 1a, the second adsorption tank 1b and the third adsorption tank 1c, and in use, the raw material filling port 11 and the raw material discharge port 14 of the first adsorption tank 1a, the second adsorption tank 1b and the third adsorption tank 1c are connected in series, and the whole is in a ring shape.

[0048] In use, three groups of adsorption tanks 1 can be used in parallel, that is, after one-stage adsorption of the raw material, the raw material is discharged into the buffer tank 2; or three groups of adsorption tanks 1 can be used in series, that is, after three-stage adsorption of the raw material, the raw material is discharged into the buffer tank 2, which increases the adsorption stages of the raw material and helps to improve the purification effect of the raw material.

[0049] At the same time, in use, when the resin column in one group of adsorption tanks 1 is saturated, one group of adsorption tanks 1 can be selected for flushing to regenerate the internal resin column, and the remaining two groups are used in series or parallel to perform two-stage or single-stage adsorption of the raw material, so as to realize non-stop regeneration of the resin column and improve the production efficiency.

[0050] And in the above production mode, when the remaining adsorption tanks 1 are used in series during the regeneration of the resin column in the adsorption tank 1, the saturation time of the resin column in the adsorption tank 1 at different adsorption stages is different, so that the regeneration of different adsorption tanks 1 can be performed in turn, and during the rotation process, the number of adsorption stages of the same adsorption tank 1 changes, and the number and order of adsorption stages experienced by each group of adsorption tanks 1 are the same, so that the regeneration interval period of each group of adsorption tanks 1 is equal, facilitating automatic control.

[0051] In some embodiments, the flushing material discharge outlets 15 of all the adsorption tanks 1 are communicated with the heat exchanger 3, and a fourth stop valve 9d is arranged between the flushing material discharge outlet 15 and the heat exchanger 3.

[0052] The flushing material filling ports of all the adsorption tanks 1 are communicated with the flushing pipeline for supplying the flushing material, and a stop valve is arranged between the flushing material filling port and the flushing pipeline.

[0053] As shown in FIG. 1, Figure 2 Each group of adsorption tanks 1 is communicated with the flushing pipeline and the heat exchanger 3, that is, any one group of adsorption tanks 1 can be independently flushed, so that the resin column inside the adsorption tank 1 is regenerated, and the normal operation of the remaining adsorption tanks 1 is not affected during the regeneration process.

[0054] In some embodiments, the flushing material filling port includes a gas filling port 12 and a flushing liquid filling port 13.

[0055] The gas filling ports 12 of all the adsorption tanks 1 are respectively communicated with the gas main pipeline 7 for supplying the gas source, and a fifth stop valve 9e is arranged between the gas filling port 12 and the gas main pipeline 7.

[0056] The flushing liquid filling ports 13 of all the adsorption tanks 1 are communicated with the flushing liquid main pipeline 8 for supplying the flushing liquid, and a sixth stop valve 9f is arranged between the flushing liquid filling port 13 and the flushing liquid main pipeline 8.

[0057] As shown in FIG. 1, Figure 1 The flushing material filling port at the top of the adsorption tank 1 includes two independent flushing liquid filling ports 13 and gas filling ports 12, and the flushing liquid filling port 13 and the gas filling port 12 of each group of adsorption tanks 1 are respectively communicated with the corresponding flushing liquid main pipeline 8 and the gas main pipeline 7, so that the flushing gas and the flushing liquid are supplied separately and do not interfere with each other.

[0058] In some embodiments, the flushing material filling port is communicated with the gas main pipeline 7 for supplying the gas source and the flushing liquid main pipeline 8 for supplying the flushing liquid through a reversing valve.

[0059] The top of the adsorption tank 1 is equipped with only one set of flushing material filling ports, and the gas main pipeline 7 and the flushing liquid main pipeline 8 are connected by a three-position three-way reversing valve. Depending on the flushing material filling situation, the corresponding main pipeline is selectively connected.

[0060] In some embodiments, the inlet end of the main gas pipeline 7 is connected to the steam pipeline and the compressed air pipeline in parallel, and a seventh shut-off valve 9g is provided between the main gas pipeline 7 and the steam pipeline and the compressed air pipeline.

[0061] like Figure 2 As shown, the inlet end of the main gas pipeline 7 is connected to both the steam pipeline and the compressed air pipeline, and the outlet ends of both the steam pipeline and the compressed air pipeline are equipped with a seventh shut-off valve 9g. Depending on the gas supply demand of the main gas pipeline 7, either the steam pipeline or the compressed air pipeline can be selectively connected.

[0062] In some embodiments, the inlet end of the flushing fluid main pipe 8 is connected to the cold water pipe and the hot water pipe in parallel, and an eighth shut-off valve 9h is provided between the flushing fluid main pipe 8 and the cold water pipe and the hot water pipe.

[0063] like Figure 2 As shown, the inlet end of the flushing fluid main pipeline 8 is connected to both a cold water pipeline and a hot water pipeline, and both the cold water pipeline and the hot water pipeline are equipped with an eighth shut-off valve 9h. Depending on the fluid supply requirements of the flushing fluid main pipeline 8, either the hot water pipeline or the cold water pipeline can be selectively connected.

[0064] In some embodiments, a phase separation tank 4 is provided at the outlet end of the heat exchanger 3 for separating the discharge from the heat exchanger 3 into phases.

[0065] like Figure 1 and Figure 2 As shown, a phase separation tank 4 is provided at the output end of the heat exchanger 3, so that the waste liquid after being cooled or condensed by the heat exchanger 3 is separated into phases in the phase separation tank 4, thereby separating the organic matter from the raw materials, and thus enabling the organic matter to be recovered into the solvent recovery tank 5.

[0066] A method for equipment regeneration applied to the above-mentioned wet-process phosphoric acid purification equipment and method is also provided, comprising the following steps:

[0067] Control the raw material inlet 11 and raw material outlet 14 to be closed, control the flushing material inlet to add hot water to rinse the resin column, and discharge the wastewater through the flushing material outlet 15;

[0068] High-temperature steam is injected through the flushing material inlet to flush the resin column, and the exhaust gas is discharged through the flushing material outlet 15.

[0069] Cold water is added through the flushing material inlet to rinse the resin column, and the wastewater is discharged through the flushing material outlet 15.

[0070] The compressed air is filled into the flushing inlet, the resin column is dried, and the waste gas is discharged through the flushing outlet 15;

[0071] The waste water or waste gas discharged from the flushing outlet 15 is controlled to enter the heat exchanger 3 to cool the waste water and condense the waste gas.

[0072] As shown in Figure 3 When the resin column is regenerated, the resin column is first rinsed with hot water to wash the raw materials attached to the surface of the resin column. During the washing process, hot water has higher solubility of raw materials than cold water, thereby ensuring the cleaning degree of the resin column. At the same time, hot water can heat the resin column once, promoting the precipitation and volatilization of organic substances inside the resin column.

[0073] Then, the resin column is heated and washed with high-temperature steam, i.e., the resin column is heated twice to increase the temperature, increase the precipitation and volatilization of organic substances, and the volatilized organic substances can be discharged with the steam flow.

[0074] The resin column is continuously rinsed with cold water, i.e., the resin column is cooled to avoid the adsorption efficiency of organic substances in the subsequent production process caused by high temperature.

[0075] Finally, the resin column is dried with compressed air to ensure the adsorption efficiency of organic substances in the production process, and the regeneration of the resin column is completed.

[0076] A use method applied to the wet-process phosphoric acid purification device and method is also provided, including the following steps:

[0077] The raw material inlet 11 and the raw material outlet 14 of the Yth-stage adsorption tank 1 are controlled to be closed, the flushing inlet of the adsorption tank 1 is controlled to be injected with flushing material, and the flushing outlet 15 of the adsorption tank 1 is controlled to discharge flushing waste, for regeneration of the resin column in the adsorption tank 1, wherein Y≤N;

[0078] The raw material inlet 11 of the Zth-stage adsorption tank 1 is controlled to be filled with raw material, and the raw material outlet 14 of the Xth-stage adsorption tank 1 is controlled to discharge raw material; when Y

[0079] As shown in Figure 2 and Figure 4As shown, when the resin column in one of the adsorption tanks 1 is saturated, taking the saturation of the resin column in the first adsorption tank 1a as an example, at this time, the regeneration of the resin column in the first adsorption tank 1a is carried out, the method adopts the above-mentioned equipment regeneration method, and the remaining second adsorption tank 1b and third adsorption tank 1c can be used in parallel or in series, taking the use in series as an example, the raw material enters from the raw material filling port 11 of the second adsorption tank 1b, is adsorbed by the internal resin column, and is then discharged from the raw material discharge port 14 of the second adsorption tank 1b, and then the raw material enters from the raw material filling port 11 of the third adsorption tank 1c, is adsorbed again by the internal resin column, and is finally discharged from the raw material discharge port 14 of the third adsorption tank 1c, in this process, the second adsorption tank 1b serves as the primary adsorption tank, and the third adsorption tank 1c serves as the secondary adsorption tank, so that the resin column in the second adsorption tank 1b is saturated preferentially, at this time, the second adsorption tank 1b is converted to be regenerated, and the third adsorption tank 1c serves as the primary adsorption tank, and the first adsorption tank 1a serves as the secondary adsorption tank, and then the regeneration of the adsorption tank 1 is carried out in turn.

[0080] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments, and the same or similar parts between various embodiments can be referred to each other.

[0081] The wet-process phosphoric acid purification equipment provided by the present application is described in detail above. In this paper, specific examples are applied to describe the principle and implementation mode of the present application, and the above embodiment is only used to help understand the method and core idea of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the principle of the present application, the present application can be improved and modified in several ways, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A wet-process phosphoric acid purification device, characterized in that, include: The adsorption tank (1) is provided with a raw material outlet (14) and a flushing material filling port at the top, and a raw material filling port (11) and a flushing material outlet (15) at the bottom. The adsorption tank (1) is filled with a resin column for adsorbing organic substances in the raw material. A heat exchanger (3) is connected in series to the flushing outlet (15) for cooling the discharge from the flushing outlet (15).

2. The wet-process phosphoric acid purification equipment according to claim 1, characterized in that, The adsorption tank (1) is in N groups, N≥3, N is a positive integer, and the N groups of adsorption tanks (1) are arranged in a ring-connected series, and a first shut-off valve (9a) is installed in the series pipeline. All of the raw material filling ports (11) of the adsorption tanks (1) are connected to the raw material filling main pipeline (6), and a second shut-off valve (9b) is provided between the raw material filling port (11) and the raw material filling main pipeline (6). The raw material outlet (14) of all the adsorption tanks (1) is connected to the buffer tank (2) for storing the produced raw materials, and a third shut-off valve (9c) is provided between the raw material outlet (14) and the buffer tank (2).

3. The wet-process phosphoric acid purification equipment according to claim 2, characterized in that, The flushing outlet (15) of all the adsorption tanks (1) is connected to the heat exchanger (3), and a fourth shut-off valve (9d) is provided between the flushing outlet (15) and the heat exchanger (3). The flushing material filling port of all the adsorption tanks (1) is connected to the flushing pipe for flushing material supply, and a shut-off valve is provided between the flushing material filling port and the flushing pipe.

4. The wet-process phosphoric acid purification equipment according to claim 3, characterized in that, The flushing material inlet includes a gas inlet (12) and a flushing fluid inlet (13); All of the gas filling ports (12) of the adsorption tanks (1) are connected to the main gas pipeline (7) for gas supply, and a fifth shut-off valve (9e) is provided between the gas filling port (12) and the main gas pipeline (7). The flushing fluid filling port (13) of all the adsorption tanks (1) is connected to the main flushing fluid pipeline (8) for flushing fluid supply, and a sixth shut-off valve (9f) is provided between the flushing fluid filling port (13) and the main flushing fluid pipeline (8).

5. The wet-process phosphoric acid purification equipment according to claim 4, characterized in that, The flushing material filling port is connected to the main gas pipeline (7) for gas supply and the main flushing liquid pipeline (8) for flushing liquid supply via a reversing valve.

6. The wet-process phosphoric acid purification equipment according to claim 4, characterized in that, The inlet end of the main gas pipeline (7) is connected to the steam pipeline and the compressed air pipeline in parallel. A seventh shut-off valve (9g) is provided between the main gas pipeline (7) and the steam pipeline and the compressed air pipeline.

7. The wet-process phosphoric acid purification equipment according to claim 4, characterized in that, The inlet end of the flushing fluid main pipe (8) is connected to the cold water pipe and the hot water pipe in parallel. An eighth shut-off valve (9h) is provided between the flushing fluid main pipe (8) and the cold water pipe and the hot water pipe.

8. The wet-process phosphoric acid purification equipment according to any one of claims 2-7, characterized in that, The heat exchanger (3) is provided with a phase separation tank (4) at the outlet end for separating the discharge of the heat exchanger (3) into phases.

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