A distillation recovery process based on potassium perchlorate waste brine

Abstract

The invention relates to the technical field of potassium perchlorate waste brine treatment, and specifically discloses a distillation recovery process based on potassium perchlorate waste brine, comprising the following steps: roughly filtering the potassium perchlorate waste brine, heating it, and passing the pre-heated potassium perchlorate waste brine into an evaporator for evaporation and crystallization; calculating and obtaining the potassium perchlorate precipitation value and wastewater inflow in the evaporation and heating process of the evaporator within a unit time t based on the evaporation initial value of the potassium perchlorate waste brine in the evaporator; comparing with the target evaporation temperature value of the potassium perchlorate waste brine and generating a control signal; adjusting the evaporation information of the evaporator based on the control signal, separating the crystal from the solution after the crystallization is completed, ensuring the stability of the evaporation and crystallization of the potassium perchlorate waste brine, avoiding the fluctuation of the crystallization precipitation rate in the crystallization process, thereby affecting the crystallization quality of potassium perchlorate, facilitating the uniform growth of potassium perchlorate crystals, and ensuring the quality of evaporation and crystallization.

Description

Technical Field

[0001] The invention relates to the technical field of potassium perchlorate waste brine treatment, and in particular to a distillation recovery process based on potassium perchlorate waste brine. Background Art

[0002] Potassium perchlorate is one of the important varieties of perchlorate, mainly used in the manufacture of fireworks, safety matches, explosives, meteorological rockets, civilian ignition coal, oxidants, etc. The traditional potassium perchlorate production process is: sodium chlorate is electrolyzed into sodium perchlorate, and then it is subjected to double decomposition reaction with potassium chloride, cooled and centrifuged to obtain potassium perchlorate. The double decomposition mother liquor after centrifugation is mainly sodium chloride, and a small amount of chlorate and perchlorate. After freezing, part of the potassium perchlorate is recovered and then discharged.

[0003] The existing potassium perchlorate production process will produce a large amount of potassium perchlorate waste brine. Since perchlorate is not easy to decompose, it will cause long-term pollution to the environment, resulting in soil salinization and a greater impact on the environment. Avoiding the discharge or recovery of potassium perchlorate waste brine has become an important treatment link; among them, evaporation of wastewater by evaporation and crystallization recovery of potassium perchlorate is a better treatment method;

[0004] However, in the process of potassium perchlorate evaporation crystallization, in order to improve the evaporation crystallization efficiency, during the evaporation process, crystal separation is carried out while potassium perchlorate waste brine is continuously introduced. At this time, during the evaporation crystallization process, it is easy to have unstable crystals, slow crystal growth, and uneven crystal quality. Summary of the invention

[0005] The object of the present invention is to provide a distillation recovery process based on potassium perchlorate waste brine to solve the above-mentioned background problems.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A distillation recovery process based on potassium perchlorate waste brine comprises the following steps:

[0008] Step 1: Pre-filtration and heating: coarsely filter the potassium perchlorate waste brine to remove impurities in the potassium perchlorate waste brine to obtain a pre-treated liquid, and then heat the pre-treated liquid through a preheater to make the potassium perchlorate waste brine reach a preheating temperature;

[0009] Step 2: passing the preheated potassium perchlorate waste brine into an evaporator for evaporation; during the evaporation process, the steam is condensed into water in the condenser and discharged, and after the potassium perchlorate waste brine is evaporated, the potassium perchlorate waste brine is controlled to be crystallized and separated;

[0010] Based on the evaporation initial value ZC of the potassium perchlorate waste brine in the evaporator, a target evaporation temperature value ZTM of the potassium perchlorate waste brine and a solubility value RJN of the potassium perchlorate waste brine at the target evaporation temperature value ZTM are obtained;

[0011] Obtain the evaporation amount of potassium perchlorate waste brine during the evaporation heating process of the evaporator within unit time t, and mark it as ZTJ; calculate and obtain the precipitation value XCZ of potassium perchlorate during the evaporation heating process of the evaporator within unit time t;

[0012] Obtain the inflow information of potassium perchlorate waste brine within unit time t; calculate the wastewater inflow LR within unit time t in the evaporator;

[0013] Based on the inflow temperature value LRT under the wastewater inflow LR; compare with the target evaporation temperature value ZTM of potassium perchlorate waste brine and generate a control signal;

[0014] Adjusting the evaporation information of the evaporator based on the control signal;

[0015] Step 3: After crystallization is complete, separate the crystals from the solution.

[0016] As a further solution of the present invention: the precipitation value XCZ of potassium perchlorate in the evaporation heating process of the evaporator within unit time t is calculated by XCZ=ZTJ×RJN.

[0017] As a further solution of the present invention: the inflow information includes an inflow temperature value LRT and an inflow concentration value LRN;

[0018] pass Calculate and obtain the wastewater inflow LR in the evaporator per unit time t.

[0019] As a further solution of the present invention: the control signal includes a cooling signal, a crystallization signal and a heating signal.

[0020] As a further solution of the present invention: comparing the inflow temperature value LRT of the potassium perchlorate waste brine with the target evaporation temperature value ZTM of the potassium perchlorate waste brine;

[0021] If the inflow temperature value LRT of the potassium perchlorate waste brine is greater than the target evaporation temperature value ZTM of the potassium perchlorate waste brine, a cooling signal is generated;

[0022] If the inflow temperature value LRT of the potassium perchlorate waste brine is equal to the target evaporation temperature value ZTM of the potassium perchlorate waste brine, a crystallization signal is generated;

[0023] The inflow temperature value LRT of the potassium perchlorate waste brine is less than the target evaporation temperature value ZTM of the potassium perchlorate waste brine, and a heating signal is generated.

[0024] As a further solution of the present invention: based on the cooling signal, the cooling medium flow rate and the cooling evaporation pressure value in the cooling pipe of the evaporator are calculated and adjusted at the same time, and then evaporation is performed; including:

[0025] Obtain the inflow temperature value LRT under the wastewater inflow LR under the cooling signal;

[0026] pass Calculate and obtain cooling information; wherein the cooling information includes a cooling medium flow value QL of the cooling pipeline; wherein b is a cooling time coefficient; and n is a cooling medium flow coefficient;

[0027] Obtain the wastewater inflow LR, and calculate the cooling evaporation pressure value PL based on the evaporation temperature and pressure model;

[0028] The total cooling capacity LZ of the potassium perchlorate waste brine in the evaporator is obtained by calculating LZ=ZC-ZTJ+LR;

[0029] Obtain the inflow temperature value LRT and target evaporation temperature value ZTM of potassium perchlorate waste brine, and further use the evaporation temperature and pressure model The cooling evaporation pressure value PL is calculated; wherein c is the cooling pressure evaporation influence coefficient, and d is the temperature evaporation influence coefficient;

[0030] Then, the potassium perchlorate waste brine in the evaporator is evaporated and crystallized within a unit time t while maintaining a cooling medium flow rate of QL and a cooling evaporation pressure value PL.

[0031] As a further solution of the present invention: based on the crystallization signal, the target evaporation temperature value ZTM is maintained, and then the evaporation temperature and pressure model is used The crystallization evaporation pressure value PL is calculated and then the target evaporation temperature is maintained, and the potassium perchlorate waste brine is evaporated within the unit time t at the crystallization evaporation pressure value PL.

[0032] As a further solution of the present invention: based on the heating signal, the evaporation heating power value and the heating evaporation pressure value are calculated, and evaporation crystallization is performed; comprising:

[0033] pass Calculate and obtain the evaporation heating power value Pj of the evaporator; where a is the temperature rise influence coefficient and k is the correction coefficient;

[0034] The total cooling capacity LZ of the potassium perchlorate waste brine in the evaporator is obtained by calculating LZ=ZC-ZTJ+LR;

[0035] Obtain the inflow temperature value LRT and target evaporation temperature value ZTM of potassium perchlorate waste brine, and use the evaporation work pressure model The heating evaporation pressure value PJ is calculated; wherein f is the heating pressure evaporation influence coefficient, and e is the power evaporation influence coefficient;

[0036] Then, the evaporation heating power of the evaporator is adjusted to Pj within the unit time t, and evaporation crystallization is performed at the state of the heating evaporation pressure value PJ.

[0037] As a further solution of the present invention: the evaporation temperature and pressure model is obtained in the following manner:

[0038] Obtain the evaporation amount ZTJ per unit time t under the evaporation initial value ZC and the target evaporation temperature value ZTM, and at the same time, obtain historical evaporation crystallization data, including historical inflow temperature values ​​LRTs, historical inflow concentration values ​​LRNs, and historical inflow flow values ​​LRs;

[0039] The total cooling amount LZs of potassium perchlorate waste brine in the evaporator is obtained by calculating LZs=ZC-ZTJ+LRs;

[0040] Obtain the historical cooling evaporation pressure value PLs when the total cooling amount value LZS is evaporated to complete the historical inflow flow value LRs within the unit time t;

[0041] The historical inflow temperature value LRTs, the historical inflow flow value LRs and the total cooling value LZs are put into the formula In the above method, the cooling pressure evaporation influence coefficient c and the temperature evaporation influence coefficient d are calculated; the evaporation temperature and pressure model can be calculated.

[0042] As a further solution of the present invention: the evaporation work pressure model is obtained in the following manner:

[0043] pass Calculate and obtain the historical evaporation heating power value Pjs when the total cooling amount LZS evaporates to complete the historical inflow flow value LRs within the unit time t;

[0044] Based on the historical evaporation heating power value Pjs, when the historical evaporation heating power value Pjs is obtained, the historical heating evaporation pressure value PJs of the historical inflow flow value LRs completed by evaporation within the unit time t;

[0045] The historical evaporation heating power value Pjs, the historical heating evaporation pressure value PJs, the historical inflow temperature value LRTs, the historical inflow flow value LRs and the total cooling value LZs are proposed to the formula In the above, the heating pressure evaporation influence coefficient f and the power evaporation influence coefficient e are calculated, and the evaporation work pressure model can be obtained.

[0046] Beneficial effects of the present invention:

[0047] In the present invention, by comparing the inflow temperature value of potassium perchlorate waste brine with the target evaporation temperature value of potassium perchlorate waste brine, different control signals are obtained, and based on the difference in the control signals, the cooling medium flow rate of the evaporator, the pressure in the evaporator and the evaporation heating power value are quickly adjusted, so that the wastewater inflow of the potassium perchlorate waste brine flowing in within the unit time t can be evaporated, and potassium perchlorate with the same precipitation value as that within the previous unit time t can be obtained; the stability of the evaporation crystallization of the potassium perchlorate waste brine is ensured, and the fluctuation of the crystallization precipitation rate during the crystallization process is avoided, thereby affecting the crystallization quality of potassium perchlorate; the adjustment is rapid and accurate, which is conducive to the uniform growth of potassium perchlorate crystals, and the quality of evaporation crystallization is ensured;

[0048] In the present invention, during the evaporation crystallization process, the execution data and the monitoring data are sent to a historical database. At this time, the historical database reconstructs the evaporation temperature and pressure model and the evaporation work pressure model based on the newly added execution data and monitoring data, that is, the cooling pressure evaporation influence coefficient c and the temperature evaporation influence coefficient d, the heating pressure evaporation influence coefficient f and the power evaporation influence coefficient e of the evaporation temperature and pressure model and the evaporation work pressure model are calculated and updated, and a more accurate evaporation temperature and pressure model and evaporation work pressure model are further obtained, which effectively ensures that accurate execution data can be obtained in a timely and effective manner during the subsequent evaporation crystallization execution process; and ensures the accuracy of potassium perchlorate crystallization and the stability of growth. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The present invention will be further described below in conjunction with the accompanying drawings.

[0050] Figure 1 It is a schematic diagram of the process structure of the present invention;

[0051] Figure 2 It is a schematic diagram of the control signal working method in the present invention. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] Embodiment 1

[0054] See also Figure 1 and Figure 2 As shown, the present invention is a distillation recovery process based on potassium perchlorate waste brine, comprising the following steps:

[0055] Step 1: Pre-filtration and heating: coarsely filter the potassium perchlorate waste brine to remove impurities in the potassium perchlorate waste brine to obtain a pre-treated liquid, and then heat the pre-treated liquid through a preheater to make the potassium perchlorate waste brine reach a preheating temperature;

[0056] Step 2: passing the preheated potassium perchlorate waste brine into an evaporator for evaporation; during the evaporation process, the steam is condensed into water in the condenser and discharged, and after the potassium perchlorate waste brine is evaporated, the potassium perchlorate waste brine is controlled to be crystallized and separated;

[0057] Step A: based on the evaporation initial value ZC of the potassium perchlorate waste brine in the evaporator, a target evaporation temperature value of the potassium perchlorate waste brine is obtained and marked as ZTM, and the potassium perchlorate waste brine is evaporated and heated;

[0058] Step B: Based on the solubility curve of potassium perchlorate waste brine, the solubility value of potassium perchlorate waste brine at the target evaporation temperature value ZTM is obtained and marked as RJN;

[0059] Obtain the evaporation amount of potassium perchlorate waste brine during the evaporation heating process of the evaporator within unit time t, and mark it as ZTJ;

[0060] The precipitation value XCZ of potassium perchlorate during the evaporation heating process of the evaporator within unit time t is calculated by XCZ=ZTJ×RJN;

[0061] Step C: Based on the evaporation amount ZTJ of the evaporator within the unit time t, the inflow information of the potassium perchlorate waste brine within the unit time t is obtained; wherein the inflow information includes the inflow temperature value LRT and the inflow concentration value LRN;

[0062] pass Calculate and obtain the wastewater inflow LR per unit time t in the evaporator;

[0063] That is, potassium perchlorate crystals with a precipitation value of XCZ are obtained after the evaporation of potassium perchlorate waste brine in the previous unit time t. Therefore, after replenishing the wastewater inflow LR to meet the precipitation value of XCZ, potassium perchlorate crystals with the same precipitation value XCZ can be obtained in the next unit time t;

[0064] Step D: Based on the inflow temperature value LRT under the wastewater inflow LR; compare with the target evaporation temperature value ZTM of potassium perchlorate waste brine and generate a control signal, wherein the control signal includes a cooling signal, a crystallization signal and a heating signal;

[0065] The inflow temperature value LRT of the potassium perchlorate waste brine is compared with the target evaporation temperature value ZTM of the potassium perchlorate waste brine;

[0066] If the inflow temperature value LRT of the potassium perchlorate waste brine is greater than the target evaporation temperature value ZTM of the potassium perchlorate waste brine, a cooling signal is obtained; and step E is executed;

[0067] If the inflow temperature value LRT of the potassium perchlorate waste brine is equal to the target evaporation temperature value ZTM of the potassium perchlorate waste brine, a crystallization signal is obtained; and step F is executed;

[0068] The inflow temperature value LRT of the potassium perchlorate waste brine is less than the target evaporation temperature value ZTM of the potassium perchlorate waste brine, and a heating signal is obtained; step G is executed;

[0069] Step E: Calculate and obtain the cooling medium flow rate and cooling evaporation pressure value in the cooling pipeline of the evaporator, adjust them simultaneously, and then perform evaporation;

[0070] Specifically include:

[0071] Step E1: obtaining an inflow temperature value LRT under a wastewater inflow LR under a cooling signal;

[0072] pass The cooling information is obtained by calculation; wherein the cooling information includes the cooling medium flow value QL of the cooling pipeline; that is, after the cooling signal is obtained, the cooling pipeline is started to open, and the temperature value of the potassium perchlorate waste brine in the evaporator is reduced to the target evaporation temperature value ZTM by controlling the cooling medium flow rate of the cooling pipeline; wherein b is the cooling time coefficient; and n is the cooling medium flow coefficient;

[0073] Step E2: Obtain the wastewater inflow LR, and calculate the cooling evaporation pressure value PL based on the evaporation temperature and pressure model;

[0074] Specifically: the total cooling amount LZ of the potassium perchlorate waste brine in the evaporator is obtained by calculating LZ=ZC-ZTJ+LR;

[0075] Obtain the inflow temperature value LRT and target evaporation temperature value ZTM of potassium perchlorate waste brine, and further use the evaporation temperature and pressure model Calculate and obtain the cooling evaporation pressure value PL;

[0076] Among them, c is the cooling pressure evaporation influence coefficient, and d is the temperature evaporation influence coefficient;

[0077] Then, the potassium perchlorate waste brine in the evaporator is evaporated and crystallized within a unit time t while maintaining a cooling medium flow rate of QL and a cooling evaporation pressure value of PL;

[0078] When the precipitation value of potassium perchlorate in unit time t is XCZ, the evaporation amount of potassium perchlorate waste brine is ZTJ. In the next unit time, based on the wastewater inflow LR of the potassium perchlorate waste brine and the inflow temperature value LRT, the cooling medium flow value QL and the cooling evaporation pressure value PL of the evaporator are calculated, and the cooling medium flow rate of the evaporator and the pressure in the evaporator are quickly adjusted. The wastewater inflow LR of the potassium perchlorate waste brine flowing in the unit time t can be evaporated, and potassium perchlorate having the same precipitation value XCZ as that in the previous unit time t is obtained; the stability of the evaporation crystallization of the potassium perchlorate waste brine is ensured, and fluctuations in the crystallization precipitation rate during the crystallization process are avoided, thereby affecting the crystallization quality of potassium perchlorate, which is conducive to the uniform growth of potassium perchlorate crystals and ensures the quality of evaporation crystallization;

[0079] Step F: Get the crystallization signal, keep the target evaporation temperature value ZTM, and then use the evaporation temperature and pressure model The crystallization evaporation pressure value PL is calculated; it should be noted that at this time, since the inflow temperature value LRT of the potassium perchlorate waste brine is equal to the target evaporation temperature value ZTM of the potassium perchlorate waste brine, the evaporation temperature and pressure model

[0080] Then, the target evaporation temperature is maintained, and the potassium perchlorate waste brine is evaporated within the unit time t at the crystallization evaporation pressure value PL;

[0081] After the new potassium perchlorate waste brine is introduced, the wastewater inflow LR of the potassium perchlorate waste brine needs to be evaporated within the next unit time t. At this time, since the target evaporation temperature value is the same as the inflow temperature value, in order to ensure the stability of the potassium perchlorate precipitation value XCZ within the unit time t, the evaporation pressure value is quickly adjusted, and the adjustment is rapid and accurate to ensure the uniform growth of potassium perchlorate crystals.

[0082] It should be noted that, under the crystallization signal state, the evaporation temperature and pressure model is used for regulation instead of the evaporation work pressure model, because the evaporation temperature and pressure model only needs to adjust the pressure under this signal, the regulation is rapid, and the regulation result is accurate;

[0083] Step G: Calculate the evaporation heating power value and the heating evaporation pressure value, and perform evaporation crystallization;

[0084] Step G1: Pass Calculate and obtain the evaporation heating power value Pj of the evaporator; where a is the temperature rise influence coefficient and k is the correction coefficient;

[0085] Step G2: obtaining the total cooling amount LZ of the potassium perchlorate waste brine in the evaporator by calculation through LZ=ZC-ZTJ+LR;

[0086] Obtain the inflow temperature value LRT and target evaporation temperature value ZTM of potassium perchlorate waste brine, and use the evaporation work pressure model The heating evaporation pressure value PJ is calculated; wherein f is the heating pressure evaporation influence coefficient, and e is the power evaporation influence coefficient;

[0087] Then, the evaporation heating power of the evaporator is adjusted to Pj within the unit time t, and evaporation crystallization is performed at the state of the heating evaporation pressure value PJ;

[0088] Since the inflow temperature value of the potassium perchlorate waste brine is lower than the target evaporation temperature value, after the new potassium perchlorate waste brine is introduced, the temperature value of the potassium perchlorate waste brine in the evaporator will be lower than the target temperature value. At this time, it is necessary to quickly increase the temperature of the potassium perchlorate waste brine, and at the same time, it is necessary to quickly evaporate the potassium perchlorate waste brine, that is, evaporate the wastewater inflow of the potassium perchlorate waste brine to obtain the same potassium perchlorate waste precipitation value as the previous unit time, and then calculate the heating evaporation pressure value. At this time, when the power of heating the potassium perchlorate waste brine is increased, the pressure is adjusted synchronously, that is, the inflowing potassium perchlorate waste brine and the potassium perchlorate waste brine in the evaporator can be quickly heated and heated, and the evaporation pressure value is increased at the same time, so that the potassium perchlorate precipitation value in the unit time t is the same as the precipitation value in the previous unit time t, and the inflow of the potassium perchlorate waste brine in this time period is completely evaporated to ensure the quality of evaporation crystallization;

[0089] Step 3: After crystallization is complete, separate the crystals from the solution.

[0090] By comparing the inflow temperature value LRT of the potassium perchlorate waste brine with the target evaporation temperature value ZTM of the potassium perchlorate waste brine, different control signals are obtained. Based on the difference in the control signals, the cooling medium flow rate of the evaporator, the pressure in the evaporator and the evaporation heating power value are quickly adjusted, so that the wastewater inflow LR of the potassium perchlorate waste brine flowing in within the unit time t can be evaporated, and potassium perchlorate having the same precipitation value XCZ as that within the previous unit time t is obtained; the stability of the evaporation crystallization of the potassium perchlorate waste brine is ensured, and fluctuations in the crystallization precipitation rate during the crystallization process are avoided, thereby affecting the crystallization quality of potassium perchlorate; the adjustment is rapid and accurate, which is conducive to the uniform growth of potassium perchlorate crystals and ensures the quality of evaporation crystallization;

[0091] Embodiment 2

[0092] Regarding the first embodiment, the evaporation temperature and pressure model in step E2 is obtained in the following manner:

[0093] Obtain the evaporation amount ZTJ per unit time t under the evaporation initial value ZC and the target evaporation temperature value ZTM, and at the same time, obtain historical evaporation crystallization data, including historical inflow temperature values ​​LRTs, historical inflow concentration values ​​LRNs, and historical inflow flow values ​​LRs;

[0094] It should be noted that, in this embodiment, the historical inflow temperature values ​​LRTs are all greater than the target evaporation temperature value ZTM;

[0095] The total cooling amount LZs of potassium perchlorate waste brine in the evaporator is obtained by calculating LZs=ZC-ZTJ+LRs;

[0096] Obtain the historical cooling evaporation pressure value PLs when the total cooling amount value LZS is evaporated to complete the historical inflow flow value LRs within the unit time t;

[0097] Based on historical cooling evaporation pressure value PLs

[0098] The historical inflow temperature value LRTs, the historical inflow flow value LRs and the total cooling value LZs are put into the formula Calculate the cooling pressure evaporation influence coefficient c and the temperature evaporation influence coefficient d;

[0099] The evaporation temperature and pressure model can be calculated

[0100] Embodiment 3

[0101] Regarding the first embodiment, the evaporation work pressure model in step G2 is obtained in the following manner:

[0102] Obtain the evaporation amount ZTJ per unit time t under the evaporation initial value ZC and the target evaporation temperature value ZTM, and obtain historical evaporation crystallization data, including historical inflow temperature values ​​LRTs, historical inflow concentration values ​​LRNs, and historical inflow flow values ​​LRs;

[0103] In this embodiment, the historical inflow temperature values ​​LRTs are all less than the target evaporation temperature value ZTM;

[0104] The total cooling amount LZs of potassium perchlorate waste brine in the evaporator is obtained by calculating LZs=ZC-ZTJ+LRs;

[0105] pass Calculate and obtain the historical evaporation heating power value Pjs when the total cooling amount LZS evaporates to complete the historical inflow flow value LRs within the unit time t;

[0106] Based on the historical evaporation heating power value Pjs, when the historical evaporation heating power value Pjs is obtained, the historical heating evaporation pressure value PJs of the historical inflow flow value LRs completed by evaporation within the unit time t;

[0107] The historical evaporation heating power value Pjs, the historical heating evaporation pressure value PJs, the historical inflow temperature value LRTs, the historical inflow flow value LRs and the total cooling value LZs are proposed to the formula In the calculation, the heating pressure evaporation influence coefficient f and the power evaporation influence coefficient e are obtained;

[0108] The evaporation work pressure model can be obtained

[0109] Embodiment 4

[0110] In the process of evaporation and crystallization, the control process in step E and step G sends the execution data and the monitoring data to the historical database. At this time, the historical database reconstructs the evaporation temperature and pressure model and the evaporation work pressure model based on the newly added execution data and monitoring data, that is, the cooling pressure evaporation influence coefficient c and the temperature evaporation influence coefficient d, the heating pressure evaporation influence coefficient f and the power evaporation influence coefficient e of the evaporation temperature and pressure model and the evaporation work pressure model are calculated and updated, and a more accurate evaporation temperature and pressure model and evaporation work pressure model are further obtained, which effectively ensures that in the subsequent evaporation and crystallization execution process, accurate execution data can be obtained in a timely and effective manner; the accuracy of potassium perchlorate crystallization and the stability of growth are ensured.

[0111] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A distillation recovery process based on potassium perchlorate waste brine, characterized in that: The following steps are involved: Step 1: Pre-filtration and heating: coarsely filter the potassium perchlorate waste brine to remove impurities in the potassium perchlorate waste brine to obtain a pre-treated liquid, and then heat the pre-treated liquid through a preheater to make the potassium perchlorate waste brine reach a preheating temperature; Step 2: passing the preheated potassium perchlorate waste brine into an evaporator for evaporation; during the evaporation process, the steam is condensed into water in the condenser and discharged, and after the potassium perchlorate waste brine is evaporated, the potassium perchlorate waste brine is controlled to be crystallized and separated; Based on the evaporation initial value ZC of the potassium perchlorate waste brine in the evaporator, a target evaporation temperature value ZTM of the potassium perchlorate waste brine and a solubility value RJN of the potassium perchlorate waste brine at the target evaporation temperature value ZTM are obtained; Obtain the evaporation amount of potassium perchlorate waste brine during the evaporation heating process of the evaporator within unit time t, and mark it as ZTJ; calculate and obtain the precipitation value XCZ of potassium perchlorate during the evaporation heating process of the evaporator within unit time t; Obtain the inflow information of potassium perchlorate waste brine within unit time t; calculate the wastewater inflow LR within unit time t in the evaporator; Based on the inflow temperature value LRT under the wastewater inflow LR; compare with the target evaporation temperature value ZTM of potassium perchlorate waste brine and generate a control signal; the control signal includes a cooling signal, a crystallization signal and a heating signal; The inflow temperature value LRT of the potassium perchlorate waste brine is compared with the target evaporation temperature value ZTM of the potassium perchlorate waste brine; If the inflow temperature value LRT of the potassium perchlorate waste brine is greater than the target evaporation temperature value ZTM of the potassium perchlorate waste brine, a cooling signal is generated; If the inflow temperature value LRT of the potassium perchlorate waste brine is equal to the target evaporation temperature value ZTM of the potassium perchlorate waste brine, a crystallization signal is generated; The inflow temperature value LRT of the potassium perchlorate waste brine is less than the target evaporation temperature value ZTM of the potassium perchlorate waste brine, and a heating signal is generated; Adjusting the evaporation information of the evaporator based on the control signal; Based on the cooling signal, the cooling medium flow rate and cooling evaporation pressure value in the cooling pipe of the evaporator are calculated and adjusted at the same time, and then evaporation is performed; including: Obtain the inflow temperature value LRT under the wastewater inflow LR under the cooling signal; pass Calculate and obtain cooling information; wherein the cooling information includes a cooling medium flow value QL of the cooling pipeline; wherein b is a cooling time coefficient; and n is a cooling medium flow coefficient; Obtain the wastewater inflow LR, and calculate the cooling evaporation pressure value PL based on the evaporation temperature and pressure model; The total cooling capacity LZ of the potassium perchlorate waste brine in the evaporator is obtained by calculating LZ=ZC-ZTJ+LR; Obtain the inflow temperature value LRT and target evaporation temperature value ZTM of potassium perchlorate waste brine, and further use the evaporation temperature and pressure model The cooling evaporation pressure value PL is calculated; wherein c is the cooling pressure evaporation influence coefficient, and d is the temperature evaporation influence coefficient; Then, the potassium perchlorate waste brine in the evaporator is evaporated and crystallized within a unit time t while maintaining a cooling medium flow rate of QL and a cooling evaporation pressure value of PL; Based on the crystallization signal, the target evaporation temperature value ZTM is maintained, and then the evaporation temperature and pressure model is used Calculate and obtain the crystallization evaporation pressure value PL; then maintain the target evaporation temperature value, and evaporate the potassium perchlorate waste brine within the unit time t at the crystallization evaporation pressure value PL; Based on the heating signal, the evaporation heating power value and the heating evaporation pressure value are calculated, and evaporation crystallization is performed; including: pass Calculate and obtain the evaporation heating power value Pj of the evaporator; where a is the temperature rise influence coefficient and k is the correction coefficient; The total cooling capacity LZ of the potassium perchlorate waste brine in the evaporator is obtained by calculating LZ=ZC-ZTJ+LR; Obtain the inflow temperature value LRT and target evaporation temperature value ZTM of potassium perchlorate waste brine, and use the evaporation work pressure model The heating evaporation pressure value PJ is calculated; wherein f is the heating pressure evaporation influence coefficient, and e is the power evaporation influence coefficient; Then, the evaporation heating power of the evaporator is adjusted to Pj within the unit time t, and evaporation crystallization is performed at the state of the heating evaporation pressure value PJ; Step 3: After crystallization is complete, separate the crystals from the solution.

2. A distillation recovery process based on potassium perchlorate waste brine according to claim 1, characterized in that: The precipitation value XCZ of potassium perchlorate during the evaporation and heating process of the evaporator within unit time t is obtained by calculation XCZ=ZTJ×RJN.

3. A distillation recovery process based on potassium perchlorate waste brine according to claim 1, characterized in that: The inflow information includes an inflow temperature value LRT and an inflow concentration value LRN; pass Calculate and obtain the wastewater inflow LR in the evaporator per unit time t.

4. A distillation recovery process based on potassium perchlorate waste brine according to claim 1, characterized in that: The evaporation temperature and pressure model is obtained as follows: Obtain the evaporation amount ZTJ per unit time t under the evaporation initial value ZC and the target evaporation temperature value ZTM, and at the same time, obtain historical evaporation crystallization data, including historical inflow temperature values ​​LRTs, historical inflow concentration values ​​LRNs, and historical inflow flow values ​​LRs; The total cooling amount LZs of potassium perchlorate waste brine in the evaporator is obtained by calculating LZs=ZC-ZTJ+LRs; Obtain the historical cooling evaporation pressure value PLs when the total cooling amount value LZS is evaporated to complete the historical inflow flow value LRs within the unit time t; The historical inflow temperature value LRTs, the historical inflow flow value LRs and the total cooling value LZs are put into the formula In the above method, the cooling pressure evaporation influence coefficient c and the temperature evaporation influence coefficient d are calculated; the evaporation temperature and pressure model can be calculated.

5. A distillation recovery process based on potassium perchlorate waste brine according to claim 1, characterized in that: The evaporation work pressure model is obtained in the following manner: pass Calculate and obtain the historical evaporation heating power value Pjs when the total cooling amount LZS evaporates to complete the historical inflow flow value LRs within the unit time t; Based on the historical evaporation heating power value Pjs, when the historical evaporation heating power value Pjs is obtained, the historical heating evaporation pressure value PJs of the historical inflow flow value LRs completed by evaporation within the unit time t; The historical evaporation heating power value Pjs, the historical heating evaporation pressure value PJs, the historical inflow temperature value LRTs, the historical inflow flow value LRs and the total cooling value LZs are proposed to the formula In the above, the heating pressure evaporation influence coefficient f and the power evaporation influence coefficient e are calculated, and the evaporation work pressure model can be obtained.

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