Recovery treatment process of high-salinity wastewater

Abstract

The invention provides a recovery treatment process of high-salinity wastewater, and relates to the technical field of wastewater treatment, and the recovery treatment process comprises the following steps: step 1, analyzing the composition of organic matters in each high-salinity wastewater, and determining the composition and content of materials in the wastewater; 2, making a corresponding treatment scheme according to specific components in the high-salinity wastewater; 3, the high-salinity wastewater is treated according to the treatment scheme, scheme adjustment and optimization are conducted, organic matter in the high-salinity wastewater is removed, and the chroma of the high-salinity wastewater is reduced; and 4, evaporating the qualified wastewater to separate out salt, and preparing to obtain qualified byproduct salt or byproduct sodium sulfite. Compared with traditional methods for removing organic matters from wastewater through Fenton oxidation, biochemistry and the like, the method is cleaner, more environmentally friendly and more effective, and the treatment cost of the high-salinity wastewater is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, in particular to a recycling and treatment process for high-salt wastewater. Background Art

[0002] High-salinity wastewater treatment reduces COD and ammonia nitrogen content in wastewater and separates the salt, enabling the recovery and utilization of industrial salt and fresh water. Currently, there are over ten methods for high-salinity wastewater treatment, including electrodialysis, evaporation crystallization, membrane separation, ion exchange, incineration, biological treatment, oxidation-reduction, and coagulation sedimentation.

[0003] For high-salinity biodegradable wastewater, the integration of distillation and biochemical methods involves pre-treating the wastewater using a multi-effect evaporation, concentration, and crystallization process to reduce the concentration of soluble inorganic salt ions before selecting an appropriate activated sludge process for COD removal. For high-COD and high-calorific value wastewater, the integration of distillation and incineration involves pre-treatment followed by incineration to ensure that the wastewater meets discharge standards. While treating high-salinity wastewater, increasing emphasis is being placed on resource recycling. For example, specific processes and technologies are being used to convert salts in the wastewater into usable products.

[0004] Currently, high-salt wastewater treatment solutions, such as Fenton oxidation and biochemical methods for removing organic matter from wastewater, have the following problems: they are unable to completely remove organic matter from the wastewater, resulting in the resulting waste salt still containing a large amount of organic matter, which cannot be utilized as a by-product salt for resource utilization; they are not clean enough and are costly. Summary of the Invention

[0005] The present invention provides a high-salt wastewater recovery and treatment process to solve at least one of the technical problems raised in the above background technology.

[0006] In order to solve the above technical problems, the present invention discloses a high-salt wastewater recovery and treatment process, comprising:

[0007] Step 1: Analyze the composition of organic matter in each high-salt wastewater to determine the composition and content of the materials in the wastewater;

[0008] Step 2: Develop corresponding treatment plans for the specific components in each high-salt wastewater;

[0009] Step 3: Treat the high-salinity wastewater according to the treatment plan, and adjust and optimize the plan to remove organic matter in the high-salinity wastewater and reduce the chroma of the high-salinity wastewater;

[0010] Step 4: Evaporating and precipitating the qualified wastewater to prepare qualified by-product salt or by-product sodium sulfite.

[0011] Preferably, the high-salt wastewater is quizalofop-ethyl cyclization-acidification wastewater, and the treatment process of the quizalofop-ethyl cyclization-acidification wastewater sequentially comprises:

[0012] Step 301: adding liquid alkali to the quizalofop-ethyl cyclization acidification wastewater to adjust the pH value to a certain value;

[0013] Step 302: adding hydrogen peroxide and heating to a certain temperature, and then keeping the temperature to react;

[0014] Step 303: After the reaction is completed, liquid alkali is added for neutralization, and the residue is filtered and removed;

[0015] Step 304: Add activated carbon to the filtrate for decolorization and filtration;

[0016] The filtrate obtained in step 4 and step 304 is subjected to MVR evaporation and salt precipitation, and the obtained crude wet salt is then added with saturated salt water at room temperature for pulping and centrifugation to obtain the final by-product wet salt;

[0017] The filtered waste residue is sent to a qualified unit for treatment, the mother liquor is evaporated and concentrated to remove the "three wastes" for biochemical treatment, and the mother liquor is pulped and centrifuged and applied to evaporate and precipitate salt.

[0018] Preferably, the high-salt wastewater is DHPPA secondary acidification wastewater, and the treatment process of the DHPPA secondary acidification wastewater comprises:

[0019] Step 311: After the DHPPA secondary acidification wastewater is adsorbed by the resin, liquid alkali is added for neutralization;

[0020] Step 312: After the resin is regenerated, the wastewater obtained in step 311 is transferred to the resin again for secondary adsorption and decolorization. The resin after decolorization and adsorption does not need to be regenerated and can be directly used for resin adsorption of the next batch of wastewater;

[0021] In step 4, the decolorized effluent obtained in step 3 is subjected to MVR evaporation and salt precipitation to obtain by-product wet salt;

[0022] The evaporated concentrated mother liquor is combined with the DHPPA secondary acidification wastewater and then subjected to resin adsorption treatment;

[0023] The resin regeneration process includes: first adding water for pre-washing, then methanol decomposition and water decomposition, biochemical treatment of the pre-wash water, combining the decomposed methanol with the decomposed water, adding liquid alkali for neutralization and then distilling to recover the methanol, recovering the methanol and applying it to methanol decomposition, and sending the distillation kettle residue to a qualified unit for treatment.

[0024] Preferably, the high-salt wastewater is nicotine wastewater;

[0025] When the nicotine wastewater is nicotine monoamination wastewater, the treatment process of the nicotine monoamination wastewater sequentially includes:

[0026] Step 321: adding liquid caustic soda to the nicotine monoamination wastewater, raising the temperature to reflux, and absorbing the dimethylamine tail gas generated by the reflux into secondary water to produce a dimethylamine aqueous solution;

[0027] Step 322: The wastewater after ammonia removal is neutralized and then distilled to remove light components, which are used as biochemical carbon sources. The wastewater after light components are filtered and then subjected to resin adsorption;

[0028] In step 4, the adsorbed water obtained in step 3 is subjected to MVR evaporation and salt precipitation to obtain by-product salt;

[0029] Evaporation and concentration of the mother liquor is applied to the resin for adsorption;

[0030] The resin regeneration process includes: first adding water for pre-washing, then methanol desorption and water desorption, pre-washing water debiochemical treatment, desorption methanol and desorption water are combined and then distilled to recover methanol, the recovered methanol is applied to methanol desorption, and the distillation kettle residue is sent to a qualified unit for treatment;

[0031] When the nicotine wastewater is diamination wastewater from nicotine, the treatment process of the diamination wastewater from nicotine sequentially includes:

[0032] Step 331: adding liquid caustic soda to the diamination wastewater from nicotine, raising the temperature to reflux, and absorbing the ammonia gas generated by the reflux into ammonia water by secondary water;

[0033] Step 332: The wastewater after ammonia removal is acidified, filtered, and then subjected to resin adsorption;

[0034] Step 333: Liquid alkali is added to neutralize the adsorbed water, and after the resin regeneration is completed, the resin adsorption and decolorization are performed again. The resin after decolorization and adsorption does not need to be regenerated and can be directly used for the next batch of wastewater resin adsorption;

[0035] In step 4, the decolorized wastewater obtained in step 3 is evaporated and salt is precipitated to obtain by-product salt;

[0036] Evaporation and concentration of the mother liquor is applied to the resin for adsorption;

[0037] The resin regeneration process includes: first adding water for pre-washing, then methanol desorption and water desorption, biochemical treatment of pre-wash water, combining desorption methanol with desorption water, adding liquid alkali for neutralization and then distilling to recover methanol, recovering methanol and applying it to methanol desorption, and sending the distillation kettle residue to a qualified unit for treatment;

[0038] When the nicotine wastewater is triacetone wastewater in nicotine, the treatment process of the triacetone wastewater in nicotine sequentially includes:

[0039] Step 341: removing light components from triacetone wastewater in nicotine, and using the light components as a biochemical carbon source;

[0040] Step 342: The wastewater from which the light components have been removed is filtered and then subjected to resin adsorption;

[0041] In step 4, the adsorbed water obtained in step 3 is evaporated and salt is precipitated to obtain by-product salt;

[0042] Evaporation and concentration of the mother liquor is applied to the resin for adsorption;

[0043] The resin regeneration process includes: first adding water for pre-washing, then performing methanol decomposition and water decomposition, removing the biochemical treatment of the pre-washing water, combining the decomposed methanol with the decomposed water and then distilling to recover the methanol, and applying the recovered methanol to methanol decomposition. The residue from the distillation kettle is sent to a qualified unit for treatment.

[0044] Preferably, when the high-salt wastewater is sodium sulfite wastewater, the treatment process of the sodium sulfite wastewater includes:

[0045] Step 351: adding liquid caustic soda to the sodium sulfite wastewater to adjust the pH to a certain value, and filtering;

[0046] Step 352: The filtrate is heated and distilled under negative pressure to be concentrated to a certain multiple, and then discharged and centrifuged at a certain temperature to obtain wet sodium sulfite salt as a by-product;

[0047] The filter residue is sent to a qualified unit for treatment; the evaporated and concentrated mother liquor is reused for evaporation and salt precipitation.

[0048] Preferably, the treatment scheme includes resin adsorption, and the resin adsorption is performed based on a resin separation device;

[0049] During the resin adsorption process, a resin separation status evaluation process is performed periodically;

[0050] During each resin separation status assessment process, the wastewater flow rate at the wastewater inlet of the resin separation device, the wastewater flow rate on the resin inlet side of the resin separation device, and the wastewater flow rate on the resin outlet side of the resin separation device are detected, as well as the flow rate at the outlet of the wastewater outlet valve of the resin separation device at the current valve opening;

[0051] and determining a first ratio of an average value of the wastewater flow rate at the resin outlet side to an average value of the wastewater flow rate at the resin inlet side corresponding to each resin separation state evaluation process;

[0052] Based on each resin separation state evaluation process, the wastewater retention coefficient is determined by the average value of the flow rate of the outlet of the corresponding wastewater outlet valve at the current valve opening and the average value of the wastewater flow rate of the wastewater inlet; and when the first ratio is greater than the first preset value, the valve flow rate loss coefficient is determined;

[0053] When any one of the following occurs: the first ratio is less than or equal to the first preset value, or the valve flow rate loss coefficient is greater than the preset loss coefficient, the control alarm device 1 is controlled to issue an early warning.

[0054] Preferably, the resin adsorption process for the current wastewater to be adsorbed includes:

[0055] Step 301: When the alarm is not sounding, the valve flow rate loss coefficients obtained from the latest several resin separation status evaluation processes are obtained, a time-valve loss coefficient variation curve is constructed, the required flow rate range of the current wastewater to be adsorbed passing through the valve outlet of the resin separation device is obtained, and a valve opening-standard flow rate variation curve corresponding to the current wastewater to be adsorbed is obtained; the valve is not cleaned during the time period corresponding to each time-valve loss coefficient variation curve;

[0056] Step 302: Based on the selected flow rates selected according to a predetermined rule within the required flow rate range and the time-valve loss coefficient variation curve obtained in step 301, determine the current predicted retention coefficient corresponding to each selected flow rate;

[0057] Step 303: Obtaining a curve of the standard flow rate range of the wastewater and the resin adsorption effect evaluation value under the corresponding standard conditions for the current wastewater to be adsorbed;

[0058] Step 304: Determine a comprehensive evaluation value for each selected flow rate based on the current predicted retention coefficient corresponding to each selected flow rate determined in step 303, the first ratio determined in the latest resin separation state evaluation process, and a curve of the standard flow rate range of wastewater and the resin adsorption effect evaluation value;

[0059] Step 305: Determine the average of N selected flow rates with the largest comprehensive evaluation values ​​and a comprehensive evaluation value greater than a preset evaluation value as the first flow rate, and determine the target valve opening corresponding to the valve opening corresponding to the current wastewater to be adsorbed-standard flow rate change curve of the first flow rate;

[0060] Step 306: Adjust the actual valve opening of the valve to the target valve opening, and set the actual water inlet flow rate to the corresponding rated water inlet flow rate for the current wastewater to be adsorbed, and perform resin adsorption on the current wastewater to be adsorbed until the valve opening adjustment condition is met.

[0061] Preferably, the conditions for adjusting the valve opening are: the difference between the first ratio determined in step 302 and the first ratio determined in the subsequent resin separation state evaluation process is greater than a first preset difference, the difference between the valve loss coefficient determined in the subsequent resin separation state evaluation process and the valve loss coefficient determined in step 302 is greater than a second preset difference, or the type of wastewater to be adsorbed changes.

[0062] Preferably, step 4 includes:

[0063] Step 41: pre-treating the qualified wastewater by heating;

[0064] Step 42: Inputting the wastewater after heating pretreatment into an evaporation device for evaporation;

[0065] Step 41 is performed based on a heat exchange device, which includes: a main heat exchanger and several auxiliary heat exchangers arranged in sequence, wherein the wastewater outlet of the preceding heat exchanger is connected to the wastewater inlet of the succeeding heat exchanger through a first pipe, a branch pipe is fixedly connected to the middle of the first pipe, a second valve is provided on the branch pipe, a first valve is provided on the first pipe near the wastewater inlet of the succeeding heat exchanger, the branch pipe is connected to a second pipe, and the second pipe is connected to the wastewater inlet of the evaporation device, and the main heat exchanger and the several auxiliary heat exchangers are all connected to a steam inlet pipe; when the first valve and the second valve are in operation, they operate at the corresponding rated opening;

[0066] During use, each heat exchanger performs a heat exchange state evaluation process for a second time period every first time period. The current heat exchange state evaluation process includes:

[0067] Determining, based on the detection, the actual heat exchange efficiency and the actual wastewater flow rate efficiency of the operating heat exchanger and the wastewater flow rate efficiency of the wastewater inlet of the operating auxiliary heat exchanger and the wastewater outlet of the previous operating heat exchanger within the current second time period;

[0068] When any of the actual heat exchange efficiency and actual wastewater flow rate efficiency of the running heat exchanger and the wastewater flow rate efficiency of the wastewater inlet of the running auxiliary heat exchanger and the wastewater outlet of the previous running heat exchanger is not within the corresponding preset range, an alarm is issued through the second alarm.

[0069] Preferably, the step 41 includes:

[0070] Step 411: obtaining the current steam parameters of the steam inlet pipe and the current temperature of the wastewater to be evaporated before entering the main heat exchanger, and obtaining the latest determined operating status evaluation parameters; the heat exchange device was not cleaned, replaced, or repaired when the current and latest determined operating status evaluation parameters were determined.

[0071] Step 412: Obtain target heat exchange parameters for the current type of wastewater to be evaporated, and determine a target inlet flow rate of the current type of wastewater to be evaporated into the main heat exchanger based on the target heat exchange parameters and step 411. The target heat exchange parameters include: a target temperature entering the evaporation device and a target flow rate range entering the evaporation device;

[0072] Step 413: Obtain a curve of wastewater flow rate-theoretical heat exchange efficiency change of the current type of wastewater to be evaporated in each heat exchanger;

[0073] Step 414: Based on steps 411, 412, and 413, the heat exchange satisfaction value of the main heat exchanger is first determined. When the heat exchange satisfaction value of the main heat exchanger is greater than or equal to 1, the actual flow rate of the wastewater inlet of the main heat exchanger is controlled to be the target inlet flow rate, the valve 1 corresponding to the main heat exchanger is controlled to be closed and the valve 2 is controlled to be opened, and the valves 1 and 2 corresponding to all auxiliary heat exchangers are controlled to be closed, thereby achieving heat exchange for the current wastewater to be evaporated (belonging to the current type of wastewater to be evaporated);

[0074] Step 415: When the heat exchange satisfaction value of the main heat exchanger is less than 1, the number of auxiliary heat exchangers that need to be operated is determined based on steps 411, 412, and 413, and valve 1 of the last auxiliary heat exchanger that needs to be operated is controlled to be closed and valve 2 is controlled to be opened, and valve 1 of the other auxiliary heat exchangers that need to be operated is controlled to be opened and valve 2 is controlled to be closed.

[0075] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments.

[0076] Compared with the prior art, the present invention has the following beneficial effects:

[0077] The alkali dosage of the quizalofop-ethyl cyclization acidification wastewater of the present invention is reduced to 2.70-3.0 eq, which is significantly lower than 4.0-6.0 eq of the existing process, effectively reducing environmental protection costs and being suitable for industrial production.

[0078] The high-salt wastewater is pretreated, and the scheme is adjusted and optimized to achieve the goal of removing organic matter in the wastewater and reducing the chroma of the wastewater, and obtaining qualified by-product salt and by-product acid.

[0079] Compared with traditional Fenton oxidation, biochemical and other methods of removing organic matter from wastewater, the technology of this project is cleaner, more environmentally friendly and more effective, greatly reducing the treatment cost of high-salt wastewater.

[0080] After treatment of chemical high-salt wastewater, the separated by-product industrial salt meets the first-level indicator of the sodium chloride industrial dry salt standard (GB / T5462-2015).

[0081] After the industrial high-salt wastewater is treated, the separated by-product sodium sulfite meets the qualified product indicators of the industrial anhydrous sodium sulfite standard (HGT2967-2010). BRIEF DESCRIPTION OF THE DRAWINGS

[0082] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0083] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0084] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0085] In addition, in the present invention, descriptions such as "first" and "second" are only used for descriptive purposes, and do not specifically refer to the order or sequence, nor are they used to limit the present invention. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions and technical features between the various embodiments can be combined with each other, but this must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0086] The present invention provides the following embodiments:

[0087] Example 1: This invention provides a high-salt wastewater recovery and treatment process, such as Figure 1 Shown, including:

[0088] Step 1: Analyze the composition of organic matter in each high-salt wastewater to determine the composition and content of the materials in the wastewater;

[0089] Step 2: Develop corresponding treatment plans for the specific components in each high-salt wastewater;

[0090] Step 3: Treat the high-salinity wastewater according to the treatment plan, and adjust and optimize the plan to remove organic matter in the high-salinity wastewater and reduce the chroma of the high-salinity wastewater;

[0091] Step 4: Evaporating and precipitating the qualified wastewater to prepare qualified by-product salt or by-product sodium sulfite.

[0092] When the high-salt wastewater is quizalofop-ethyl cyclization-acidification wastewater, the treatment process of the quizalofop-ethyl cyclization-acidification wastewater sequentially comprises:

[0093] Step 301: adding liquid alkali to the quizalofop-ethyl cyclization acidification wastewater to adjust the pH value to a certain value (which may be 10-12);

[0094] Step 302: adding hydrogen peroxide and heating to a certain temperature (which may be 60-80°C), and then keeping the temperature to react;

[0095] Step 303: After the reaction is completed, liquid alkali is added for neutralization, and the residue is filtered and removed;

[0096] Step 304: Add activated carbon to the filtrate for decolorization and filtration;

[0097] In the above step 4, the filtrate obtained in step 304 is subjected to MVR evaporation and salt precipitation, and the obtained crude wet salt is then added with saturated salt water at room temperature for pulping and centrifugation to obtain the final by-product wet salt;

[0098] The filtered waste residue is sent to a qualified unit for treatment, the mother liquor is evaporated and concentrated to remove the "three wastes" for biochemical treatment, and the mother liquor is pulped and centrifuged and applied to evaporate and precipitate salt.

[0099] The high-salt wastewater is DHPPA secondary acidification wastewater, and the treatment process of the DHPPA secondary acidification wastewater includes:

[0100] Step 311: After the DHPPA secondary acidification wastewater is adsorbed by the resin, liquid alkali is added for neutralization;

[0101] Step 312: After the resin is regenerated, the wastewater obtained in step 311 is transferred to the resin again for secondary adsorption and decolorization. The resin after decolorization and adsorption does not need to be regenerated and can be directly used for resin adsorption of the next batch of wastewater;

[0102] In step 4, the decolorized effluent obtained in step 3 is subjected to MVR evaporation and salt precipitation to obtain by-product wet salt;

[0103] The evaporated concentrated mother liquor is combined with the DHPPA secondary acidification wastewater and then subjected to resin adsorption treatment;

[0104] The resin regeneration process includes: first adding water for pre-washing, then methanol decomposition and water decomposition, biochemical treatment of the pre-wash water, combining the decomposed methanol with the decomposed water, adding liquid alkali for neutralization and then distilling to recover the methanol, recovering the methanol and applying it to methanol decomposition, and sending the distillation kettle residue to a qualified unit for treatment.

[0105] When the high-salt wastewater is nicotine wastewater;

[0106] When the nicotine wastewater is nicotine monoamination wastewater, the treatment process of the nicotine monoamination wastewater sequentially includes:

[0107] Step 321: adding liquid caustic soda to the nicotinamide amination wastewater, raising the temperature to reflux, and absorbing the dimethylamine tail gas generated in the reflux by secondary water to produce a dimethylamine aqueous solution (returned to the nicotinamide amination section);

[0108] Step 322: The wastewater after ammonia removal is neutralized and then distilled to remove light components, which are used as biochemical carbon sources. The wastewater after light components are filtered and then subjected to resin adsorption;

[0109] In step 4, the adsorbed water obtained in step 3 is subjected to MVR evaporation and salt precipitation to obtain by-product salt;

[0110] Evaporation and concentration of the mother liquor is applied to the resin for adsorption;

[0111] The resin regeneration process includes: first adding water for pre-washing, then methanol desorption and water desorption, pre-washing water debiochemical treatment, desorption methanol and desorption water are combined and then distilled to recover methanol, the recovered methanol is applied to methanol desorption, and the distillation kettle residue is sent to a qualified unit for treatment;

[0112] When the nicotine wastewater is diamination wastewater from nicotine, the treatment process of the diamination wastewater from nicotine sequentially includes:

[0113] Step 331: Liquid caustic soda is added to the nicotine diamination wastewater, and the temperature is raised to reflux. The ammonia generated in the reflux is absorbed by secondary water to produce ammonia water (recycled to the nicotine disulfonamide section); the secondary water is the graded water used to absorb the tail gas in the process.

[0114] Step 332: The wastewater after ammonia removal is acidified, filtered, and then subjected to resin adsorption;

[0115] Step 333: Liquid alkali is added to neutralize the adsorbed water, and after the resin regeneration is completed, the resin adsorption and decolorization are performed again. The resin after decolorization and adsorption does not need to be regenerated and can be directly used for the next batch of wastewater resin adsorption;

[0116] In step 4, the decolorized wastewater obtained in step 3 is evaporated and salt is precipitated to obtain by-product salt;

[0117] Evaporation and concentration of the mother liquor is applied to the resin for adsorption;

[0118] The resin regeneration process includes: first adding water for pre-washing, then methanol desorption and water desorption, biochemical treatment of pre-wash water, combining desorption methanol with desorption water, adding liquid alkali for neutralization and then distilling to recover methanol, recovering methanol and applying it to methanol desorption, and sending the distillation kettle residue to a qualified unit for treatment;

[0119] When the nicotine wastewater is triacetone wastewater in nicotine, the treatment process of the triacetone wastewater in nicotine sequentially includes:

[0120] Step 341: removing light components from triacetone wastewater in nicotine, and using the light components as a biochemical carbon source;

[0121] Step 342: The wastewater from which the light components have been removed is filtered and then subjected to resin adsorption;

[0122] In step 4, the adsorbed water obtained in step 3 is evaporated and salt is precipitated to obtain by-product salt;

[0123] Evaporation and concentration of the mother liquor is applied to the resin for adsorption;

[0124] The resin regeneration process includes: first adding water for pre-washing, then performing methanol decomposition and water decomposition, removing the biochemical treatment of the pre-washing water, combining the decomposed methanol with the decomposed water and then distilling to recover the methanol, and applying the recovered methanol to methanol decomposition. The residue from the distillation kettle is sent to a qualified unit for treatment.

[0125] When the high-salt wastewater is sodium sulfite wastewater, the treatment process of the sodium sulfite wastewater includes:

[0126] Step 351: adding liquid caustic soda to the sodium sulfite wastewater to adjust the pH to a certain value, and filtering;

[0127] Step 352: The filtrate is heated and distilled under negative pressure to be concentrated to a certain multiple, and then discharged and centrifuged at a certain temperature to obtain wet sodium sulfite salt as a by-product;

[0128] The filter residue is sent to a qualified unit for treatment; the evaporated and concentrated mother liquor is reused for evaporation and salt precipitation.

[0129] (1) The wastewater from the cyclization of quinquinol mainly contains acetic acid, sulfide and some phenolic substances. The wastewater has a strong odor and a dark color. The wastewater is pre-treated with oxidants such as hydrogen peroxide and hypochlorous acid to oxidize and remove most of the sulfide and phenolic substances. Then, activated carbon decolorization or resin adsorption is carried out according to the specific treatment conditions. After obtaining qualified treated wastewater, it is evaporated to obtain qualified by-product salt.

[0130] (2) DHPPA secondary acidification wastewater

[0131] DHPPA secondary acidification wastewater contains about 1% phenolic substances, and its biochemical treatment effect is poor. The wastewater can be treated with resin adsorption to remove organic phenols in the wastewater, and then evaporated and salted to obtain qualified by-product salt.

[0132] (3) Nicosulfuron wastewater

[0133] The wastewater from the monoamination of nicotine mainly contains dimethylamine and a small amount of organic matter. The wastewater is first treated to remove ammonia, and then a small amount of organic matter is removed by resin adsorption before evaporation and salt precipitation.

[0134] The diamination wastewater in nicotine mainly contains ammonia and a small amount of organic matter. The wastewater is first treated to remove ammonia, and then a small amount of organic matter is removed by resin adsorption before evaporation and salt precipitation.

[0135] The triacetone wastewater in nicotine contains a small amount of acetone, ethanol and a small amount of organic matter. It can be directly treated with resin adsorption or the solvent can be removed by distillation and then treated with resin adsorption to remove a small amount of organic matter and then evaporate and precipitate salt.

[0136] (4) Sodium sulfite wastewater

[0137] Sodium sulfite wastewater comes from the tail gas absorption of the chlorination reaction using thionyl chloride. The chlorinated tail gas produces hydrogen chloride and sulfur dioxide. The chlorinated tail gas is absorbed by tertiary water to remove hydrogen chloride in the tail gas, and then the sulfur dioxide is absorbed by liquid alkali to form sodium sulfite wastewater. During the absorption process, the oxygen entering the system needs to be controlled to avoid the oxidation of sulfurous acid into sulfuric acid. After the absorption is saturated, the salt can be evaporated and precipitated to obtain the by-product sodium sulfite.

[0138] Traditional methods of removing organic matter from wastewater, such as Fenton oxidation and biochemical treatment, have the following drawbacks:

[0139] Fenton oxidation:

[0140] Chemical consumption and sludge generation: large amounts of H2O2 and Fe need to be added 2+ The cost of chemicals is high and iron-containing sludge is produced. If the sludge is not properly disposed of (such as landfill), the iron ions and undegraded organic matter in it may seep into the soil and water, causing secondary pollution.

[0141] Acidic conditions and equipment corrosion: The reaction needs to be carried out in an acidic environment (around pH 2-4), which places high demands on the equipment material. If anti-corrosion measures are not in place, equipment corrosion will lead to the dissolution of metal ions, polluting wastewater, and may also shorten the equipment life and increase the generation of solid waste (scrapped equipment).

[0142] Biochemistry:

[0143] High requirements for wastewater quality: Microorganisms are sensitive to water quality (such as pH, temperature, and toxic substances). If the wastewater contains high concentrations of difficult-to-degrade organic matter, heavy metals, and highly toxic substances (such as phenols and cyanides), it will inhibit or even kill the microorganisms, causing the treatment system to collapse. If it goes directly to biochemical treatment without pretreatment, it is equivalent to "transferring the pollution risk" and destroying the environmental friendliness of biological treatment.

[0144] Sludge disposal issues: The biochemical process produces residual sludge. If the sludge has a high moisture content and is not properly treated (such as not undergoing anaerobic digestion and reduction, or not being landfilled or incinerated to meet standards), the organic matter, pathogens, and heavy metals in the sludge will pollute the soil, water, and atmosphere, posing a new environmental hazard.

[0145] Limitation of degradation efficiency: For some difficult-to-degrade, complex organic substances (such as polycyclic aromatic hydrocarbons and long-chain alkyl compounds), simple biochemical methods have slow degradation and low removal rates, and need to be combined with pretreatment / deep treatment processes such as Fenton oxidation. Otherwise, they cannot meet strict environmental emission standards, which indirectly reduces the "cleanliness" of the single biochemical method.

[0146] The beneficial effects of the above technical solution are:

[0147] The alkali dosage of the quizalofop-ethyl cyclization acidification wastewater of the present invention is reduced to 2.70-3.0 eq, which is significantly lower than 4.0-6.0 eq of the existing process, effectively reducing environmental protection costs and being suitable for industrial production.

[0148] The high-salt wastewater is pretreated, and the scheme is adjusted and optimized to achieve the goal of removing organic matter in the wastewater and reducing the chroma of the wastewater, and obtaining qualified by-product salt and by-product acid.

[0149] Compared with traditional Fenton oxidation, biochemical and other methods of removing organic matter from wastewater, the technology of this project is cleaner, more environmentally friendly and more effective, greatly reducing the treatment cost of high-salt wastewater.

[0150] After treatment of chemical high-salt wastewater, the separated by-product industrial salt meets the first-level indicator of the sodium chloride industrial dry salt standard (GB / T5462-2015).

[0151] After the industrial high-salt wastewater is treated, the separated by-product sodium sulfite meets the qualified product indicators of the industrial anhydrous sodium sulfite standard (HGT2967-2010).

[0152] Example 2, based on Example 1, the treatment scheme includes resin adsorption, and the resin adsorption is performed based on a resin separation device;

[0153] During the resin adsorption process, a resin separation status evaluation process is performed periodically;

[0154] During each resin separation status assessment process, the wastewater flow rate at the wastewater inlet of the resin separation device is tested (the corresponding rated water inlet flow rate is set for each type of wastewater to be adsorbed), the wastewater flow rate on the resin inlet side of the resin separation device, and the wastewater flow rate on the resin outlet side of the resin separation device, as well as the flow rate at the outlet of the valve of the wastewater outlet of the resin separation device at the current valve opening are tested; in each resin separation status assessment process, the above parameters are tested simultaneously; the above rated flow rate is: for a specific type of wastewater to be adsorbed (such as a type of wastewater with fixed parameters such as composition and concentration (or within the same range)), after process design and verification, the standard flow rate that should be maintained at the wastewater inlet when the resin separation device is able to treat it stably and efficiently.

[0155] and determining a first ratio of an average value of the wastewater flow rate at the resin outlet side to an average value of the wastewater flow rate at the resin inlet side corresponding to each resin separation state evaluation process;

[0156] Based on each resin separation state evaluation process, the wastewater retention coefficient is determined based on the average value of the flow rate of the outlet of the corresponding wastewater outlet valve at the current valve opening and the average value of the wastewater flow rate of the wastewater inlet; and when the first ratio is greater than the first preset value, the valve flow rate loss coefficient is determined; the wastewater outlet pipe of the wastewater outlet is connected to a valve;

[0157] When any one of the following occurs: the first ratio is less than or equal to the first preset value, or the valve flow rate loss coefficient is greater than the preset loss coefficient, the control alarm device 1 is controlled to issue an early warning.

[0158] Wherein, the first ratio=the average value of the wastewater flow rate at the resin outlet side ÷ the average value of the wastewater flow rate at the resin inlet side;

[0159] Among them, the valve flow rate loss coefficient of the resin separation state evaluation process is for: ,in, For the resin separation status evaluation process, the average flow rate of the wastewater outlet valve at the current valve opening is The theoretical flow rate of the outlet of the valve serving as the wastewater outlet at the current opening of the valve (determined based on the initially used valve and wastewater outlet pipe);

[0160] The wastewater retention coefficient K of the resin separation status evaluation process is calculated based on the following formula:

[0161] ; Wherein, Q is the average value of the wastewater flow rate of the wastewater inlet during the resin separation state evaluation process; B is the internal diameter of the wastewater outlet pipe at the valve outlet; is the inner diameter of the resin separation device; h is the height of the resin in the resin separation device; t is the unit time.

[0162] The beneficial effects of the above technical solution are:

[0163] Simultaneously monitor the wastewater inlet flow rate, the flow rate on both sides of the resin, and the rated valve opening flow rate, capturing state changes throughout the entire process from "fluid input - resin adsorption - fluid output." For example, when the resin is clogged, the flow rate on the resin outlet decreases. This first ratio allows for precise identification, avoiding misjudgment based on a single parameter.

[0164] Valve flow loss coefficient: Compares the actual flow rate with the theoretical flow rate at the rated valve opening to identify valve wear and blockage (such as scaling causing insufficient opening) and avoid system pressure fluctuations caused by valve failure.

[0165] Wastewater retention coefficient: Combined with flow rate, pipe diameter, and resin height, it quantifies the residence time and flow state of wastewater in the resin separation device, ensures the adequacy of the adsorption reaction, and indirectly monitors the resin adsorption efficiency (if the residence time is too short, the adsorption is insufficient, and if it is too long, it may cause secondary pollution).

[0166] Periodic status assessments prevent equipment damage caused by accumulated faults. By providing early warnings of resin blockage and valve wear, resin can be cleaned and valves maintained in a timely manner, reducing resin breakage and pipeline corrosion caused by long-term abnormal operation, and lowering equipment operation and maintenance costs and replacement frequency.

[0167] The early warning is triggered by the dual conditions of "first ratio + valve flow rate loss coefficient", covering the two core problems of "resin section blockage" and "valve section failure".

[0168] The long-term monitored first ratio and valve flow rate loss coefficient can provide reverse guidance for resin selection (such as replacing with anti-pollution resin if frequent blockage occurs) and pipeline / valve design (such as optimizing valve flow channels to reduce wear), thereby promoting continuous process iteration and adapting to wastewater treatment needs in different water quality and water volume scenarios.

[0169] Example 3, based on Example 2, the resin adsorption process for the current wastewater to be adsorbed includes:

[0170] Step 301: When the alarm device 1 is not sounding, obtain the valve flow rate loss coefficients obtained from the latest several resin separation state evaluation processes, construct a time-valve loss coefficient variation curve (the abscissa of the time-valve loss coefficient variation curve is time (specifically, the time of the last detection in each resin separation state evaluation process), and the ordinate is the valve loss coefficient determined by the corresponding resin separation state evaluation process), obtain the current required flow rate range of the wastewater to be adsorbed through the valve outlet of the resin separation device (determined according to process efficiency requirements, etc.), and obtain the valve opening-standard flow rate variation curve corresponding to the current wastewater to be adsorbed; the valve is not cleaned during the time period corresponding to each time-valve loss coefficient variation curve;

[0171] The valve opening-standard flow rate curve corresponding to the current wastewater to be adsorbed is determined through testing based on the initially used valve, resin separation device, the same type of wastewater as the current wastewater to be adsorbed (e.g., parameters such as composition and concentration are identical or within the same range), the rated flow rate corresponding to the current type of wastewater to be adsorbed, and the initially used resin for the current type of wastewater to be adsorbed. In the valve opening-standard flow rate curve, the horizontal axis represents the valve opening, and the vertical axis represents the flow rate at the valve outlet obtained through testing.

[0172] Step 302: Based on the selected flow rates selected according to a predetermined rule within the required flow rate range (which may be selected according to a preset flow rate interval), and the time-valve loss coefficient variation curve obtained in step 301, determine the current predicted retention coefficient corresponding to each selected flow rate;

[0173] ;

[0174] Where D is the valve flow loss coefficient determined during the latest resin separation status assessment process; The rated flow rate corresponding to the current wastewater to be adsorbed; Select the flow rate for the fth one; The height of the resin corresponding to the current wastewater to be adsorbed; is the average value of the valve loss coefficient decrease per unit time obtained based on the time-valve loss coefficient variation curve obtained in step 301; The ideal valve opening adjustment time interval corresponding to the current wastewater to be adsorbed (the "ideal" time interval determined in advance through testing or simulation is used to standardize the frequency of valve opening evaluation and adjustment, so that the parameter adjustment of the entire adsorption process has a time rhythm, which is neither too frequent (to avoid frequent equipment operation loss and data fluctuation interference) nor too long (to prevent the accumulation of changes in valve status, water quality, etc. that affect the adsorption effect));

[0175] Step 303: Obtain a curve of the standard flow rate range of the wastewater under corresponding standard conditions and the resin adsorption effect evaluation value (determined through experiments, where the abscissa is the flow rate at the valve outlet during the experiment, and the ordinate is the resin adsorption effect evaluation value corresponding to the abscissa).

[0176] The standard conditions corresponding to the current wastewater to be adsorbed are: the initially used valve, resin separation device and the same type of wastewater as the current wastewater to be adsorbed (such as the same or within the same range of parameters such as composition and concentration), the rated flow corresponding to the same type of wastewater as the current wastewater to be adsorbed, and the initially used resin corresponding to the same type of wastewater as the current wastewater to be adsorbed.

[0177] The resin adsorption effect evaluation value is calculated based on the following formula: ;

[0178] T is the number of evaluation indicators for resin adsorption effect (including the removal rate of each target pollutant); is the evaluation weight of the j-th resin adsorption effect evaluation index (the value is greater than 0 and less than 1); is the compliance of the jth resin adsorption effect evaluation index. When the jth resin adsorption effect evaluation index meets the corresponding resin adsorption effect evaluation index requirements, then The value is 1, otherwise The value is 0;

[0179] Step 304: Determine a comprehensive evaluation value for each selected flow rate based on the current predicted retention coefficient corresponding to each selected flow rate determined in step 303, the first ratio determined in the latest resin separation state evaluation process, and a curve of the standard flow rate range of wastewater and the resin adsorption effect evaluation value;

[0180] ;

[0181] is the comprehensive evaluation value of the f-th selected flow velocity; Select the flow rate for the fth one; The standard flow rate range of wastewater - resin adsorption effect evaluation value curve for the current wastewater to be adsorbed under the corresponding standard conditions Corresponding resin adsorption effect evaluation value; 、 They are the first ratio evaluation weight and the retention coefficient evaluation weight (both are greater than 0 and less than 1, such as 0.6 and 0.4 respectively); is the predicted retention coefficient corresponding to f selected flow rates; is the ideal retention coefficient of the current wastewater to be adsorbed; a first ratio value determined during the most recent resin separation status assessment process; is the ideal first ratio of the current wastewater to be adsorbed; the ideal retention coefficient of the current wastewater to be adsorbed and the ideal first ratio of the current wastewater to be adsorbed are the retention coefficient and first ratio when the resin adsorption effect evaluation value is the maximum, determined based on the current wastewater to be adsorbed after adjusting the retention coefficient and the first ratio test under the corresponding standard conditions;

[0182] Step 305: Determine N (N can be 5) with the largest comprehensive evaluation values ​​that are greater than a preset evaluation value, select the average of the flow rates as the first flow rate, and determine the target valve opening corresponding to the valve opening corresponding to the current wastewater to be adsorbed - standard flow rate change curve for the first flow rate;

[0183] Step 306: Adjust the actual valve opening of the valve to the target valve opening, and set the actual water inlet flow rate to the corresponding rated water inlet flow rate for the current wastewater to be adsorbed, and perform resin adsorption on the current wastewater to be adsorbed until the valve opening adjustment condition is met.

[0184] The conditions for adjusting the valve opening are: the difference between the first ratio (such as 0.9) determined in step 302 and the first ratio (such as 0.8) determined in the subsequent resin separation state evaluation process is greater than a first preset difference (such as 0.5); the difference between the valve loss coefficient (such as 0.2) determined in the subsequent resin separation state evaluation process and the valve loss coefficient (such as 0.1) determined in step 302 is greater than a second preset difference (such as 0.7); or the type of wastewater to be adsorbed changes.

[0185] The beneficial effects of the above technical solution are:

[0186] Using the "time-valve loss coefficient curve" and "valve opening-standard flow rate curve" (step 301), the valve state decay pattern is tracked in real time. Combined with the process requirements (required flow rate range) of the wastewater to be adsorbed, the valve opening is dynamically matched to the required wastewater flow rate. For example, the valve loss coefficient varies over time, and the curve accurately reflects this change, preventing flow rate loss caused by valve aging and ensuring a stable adsorption process.

[0187] Using the "predicted retention coefficient" (step 302) and "comprehensive evaluation value" (step 304) models, parameters such as valve status, flow rate, and resin adsorption performance are quantitatively correlated. This ability to predict adsorption performance at different flow rates allows process control to be upgraded from "experience-driven" to "data-driven," significantly improving adsorption accuracy.

[0188] Based on the "standard wastewater flow rate range - resin adsorption effect evaluation value curve" (step 303), the flow rate with the "optimal comprehensive evaluation value" is selected (step 305). This maximizes wastewater treatment capacity while ensuring pollutant removal rate (e.g., the target pollutant removal rate is constrained by the evaluation value). For example, the "first flow rate" is obtained by averaging N optimal flow rates. This avoids excessively high flow rates that lead to insufficient adsorption, while also preventing excessively low flow rates that limit production capacity, thus achieving a balance between "treatment efficiency" and "effect."

[0189] The parameter adjustment is dynamically triggered by the “conditions for valve opening adjustment” (step 306) to adapt to working conditions such as water quality fluctuations (changes in wastewater types) and equipment aging (changes in valve loss coefficients).

[0190] The opening-flow rate curve and effect evaluation value curve (steps 301 and 303) constructed based on "standard conditions" (initial valve, resin, and wastewater parameters) can be directly reused in similar wastewater treatment scenarios. New projects only need to replace water quality parameters to quickly adapt the process, shortening the technology development cycle and reducing project implementation costs.

[0191] Example 4, based on Example 1, step 4 includes:

[0192] Step 41: pre-treating the qualified wastewater by heating;

[0193] Step 42: Inputting the wastewater after heating pretreatment into an evaporation device for evaporation;

[0194] Step 41 is performed based on a heat exchange device, which includes: a main heat exchanger and several auxiliary heat exchangers arranged in sequence, wherein the wastewater outlet of the preceding heat exchanger is connected to the wastewater inlet of the succeeding heat exchanger through a first pipe, a branch pipe is fixedly connected to the middle of the first pipe, a second valve is provided on the branch pipe, a first valve is provided on the first pipe near the wastewater inlet of the succeeding heat exchanger, the branch pipe is connected to a second pipe, and the second pipe is connected to the wastewater inlet of the evaporation device, and the main heat exchanger and the several auxiliary heat exchangers are all connected to a steam inlet pipe; when the first valve and the second valve are in operation, they operate at the corresponding rated opening;

[0195] During use, each heat exchanger performs a heat exchange state evaluation process for a second time period every first time period. The current heat exchange state evaluation process includes:

[0196] Determine operating status evaluation parameters within the current second time period based on the detection, the operating status evaluation parameters including: actual heat exchange efficiency (determined based on a heat exchange efficiency model of the heat exchanger) and actual wastewater flow rate efficiency (average flow rate at the wastewater outlet of the heat exchanger during the current second time period divided by average flow rate at the wastewater inlet of the heat exchanger during the current second time period), and wastewater flow rate efficiency between the wastewater inlet of the operating auxiliary heat exchanger and the wastewater outlet of the previous operating heat exchanger (average flow rate at the wastewater inlet of the auxiliary heat exchanger during the current second time period divided by average flow rate at the wastewater outlet of the previous operating heat exchanger).

[0197] When any of the operating status evaluation parameters is out of the corresponding preset range, an alarm is sounded through the second alarm.

[0198] The beneficial effects of the above scheme are:

[0199] A series heat exchanger network (primary heat exchanger + auxiliary heat exchanger) connects the wastewater outlet of the preceding heat exchanger to the wastewater inlet of the succeeding heat exchanger in a series configuration, achieving a cascaded heat utilization system. For example, the primary heat exchanger preheats the wastewater to a certain temperature, and the auxiliary heat exchanger further heats it. This reduces steam consumption compared to a single-stage heat exchanger (the steam heat is absorbed in multiple stages).

[0200] By adjusting the wastewater flow direction through valves 1 and 2 (such as bypassing some auxiliary heat exchangers), the system can maintain continuous operation when some heat exchangers fail or their efficiency decreases, while avoiding interruption of the entire process due to failure of a single heat exchanger.

[0201] The heat exchange status is assessed for a second duration (e.g., 30 seconds to 2 minutes) every first duration (e.g., 5-30 minutes, which can be adjusted based on the specific efficiency determined in the previous assessment). Key parameters such as actual heat exchange efficiency and wastewater flow rate efficiency are monitored in real time. Alarm 2 triggers an alarm when any parameter deviates from the preset range, facilitating timely cleaning of scale and equipment maintenance to prevent a decrease in evaporation efficiency due to heat exchanger performance degradation.

[0202] The present invention sets a main heat exchanger according to all wastewater to be treated that can be preheated by the heat exchange device, ensuring that all wastewater to be treated that can be preheated by the heat exchange device needs to use the main heat exchanger for heat exchange, but the number of auxiliary heat exchangers that need to be opened (which may be 0) varies according to different types of wastewater, so as to meet the heat exchange requirements of different types of wastewater and avoid the situation where a fixed heat exchanger can meet the heat exchange requirements of a small number of types of wastewater; and the number of auxiliary heat exchangers can be increased when the actual heat exchange efficiency, wastewater flow rate efficiency, etc. of the above-mentioned heat exchange device deviate but do not reach the warning state.

[0203] Example 4, based on Example 3, step 41 includes:

[0204] Step 411: obtaining the current steam parameters (including steam temperature and steam flow) of the steam inlet pipe and the current temperature of the wastewater to be evaporated before entering the main heat exchanger, and obtaining the latest determined operating status evaluation parameters;

[0205] Step 412: Obtain the target heat exchange parameters of the wastewater to be evaporated, and determine the target flow rate of the wastewater to be evaporated into the main heat exchanger based on the target heat exchange parameters and step 411. ,The target heat exchange parameters include: target temperature entering the evaporation device, target flow rate range entering the evaporation device;

[0206] ;

[0207] is the maximum value of the target flow rate range entering the evaporation device among the target heat exchange parameters of the current type of wastewater to be evaporated; The product of the efficiency of all heat exchangers initially required for the current type of wastewater to be evaporated and the corresponding latest determined actual wastewater flow rate; The product of the wastewater flow rate efficiency of the wastewater inlet of the newly determined auxiliary heat exchanger and the wastewater outlet of the previously operated heat exchanger for all heat exchangers initially required for the current type of wastewater to be evaporated;

[0208] All heat exchangers required initially are: the minimum heat exchanger configuration set determined through heat balance calculation and testing based on the baseline wastewater temperature, the target heat exchange parameters of the wastewater to be evaporated, the baseline steam parameters, and other basic conditions, all in their initial operating state (the aforementioned efficiencies are relatively high). Same type of wastewater: parameters such as composition and concentration are the same or within the same range;

[0209] Step 413: Obtain a curve showing the change in wastewater flow rate versus theoretical heat exchange efficiency for each heat exchanger for the current type of wastewater to be evaporated (the horizontal axis represents the average wastewater flow rate for the heat exchanger, and the vertical axis represents the theoretical heat exchange efficiency corresponding to the horizontal axis, which is determined by testing based on the heat exchanger initially used for the current type of wastewater to be evaporated). The curve showing the change in wastewater flow rate versus theoretical heat exchange efficiency for each heat exchanger is determined based on a heat exchange efficiency model or test based on a baseline wastewater temperature and baseline steam parameters for each heat exchanger in its initial use state.

[0210] Step 414: Based on steps 411, 412, and 413, the heat exchange satisfaction value of the main heat exchanger is first determined. When the heat exchange satisfaction value of the main heat exchanger is greater than or equal to 1, the actual flow rate of the wastewater inlet of the main heat exchanger is controlled to be the target inlet flow rate, the valve 1 corresponding to the main heat exchanger is controlled to be closed and the valve 2 is controlled to be open, and the valves 1 and 2 corresponding to all auxiliary heat exchangers are controlled to be closed to achieve heat exchange of the current wastewater to be evaporated. The actual flow rate of the current wastewater to be evaporated entering the main heat exchanger is the target inlet flow rate. ;

[0211] ;

[0212] in, is the heat transfer satisfaction value of the main heat exchanger; The minimum value of the target temperature of the wastewater entering the evaporation device among the target heat exchange parameters of the current wastewater to be evaporated; is the steam temperature (the steam temperature in the current steam parameters of the steam inlet pipe); Actual wastewater flow rate efficiency of the main heat exchanger in the evaluation parameters for the most recently determined operating state; The current temperature of the wastewater to be evaporated before entering the main heat exchanger; for The vertical coordinate corresponding to the wastewater flow rate-theoretical heat exchange efficiency change curve of the main heat exchanger corresponding to the current type of wastewater to be evaporated; The actual heat transfer efficiency of the main heat exchanger in the evaluation parameters for the most recently determined operating state; The vertical coordinate of the wastewater flow rate-theoretical heat exchange efficiency change curve corresponding to the average wastewater flow rate of the main heat exchanger in the latest determined operating status evaluation parameters; 、 They are flow rate weight 1 and flow rate weight 2 (the values ​​are greater than 0 and less than 1, and can be 0.5 and 0.5 respectively); Based on the heat transfer efficiency model and Determine the temperature of the wastewater after heat exchange; is the average flow rate of wastewater in the heat exchanger; is the current steam flow rate of the steam inlet pipe;

[0213] The heat transfer efficiency model may be an existing heat transfer efficiency model, such as:

[0214] ;

[0215] is the heat transfer efficiency of the current heat exchanger (the heat transfer efficiency of the main heat exchanger is substituted into the above , other heat exchangers can be substituted in for reference); 、 They are the wastewater temperature at the wastewater outlet and the wastewater temperature at the wastewater inlet of the current heat exchanger (substitute ); is the specific heat capacity of the current wastewater; for the current; is the average flow rate of the wastewater in the current heat exchanger (the average flow rate of the wastewater in the main heat exchanger is substituted ); are respectively the steam inlet flow rate of the current heat exchanger, the specific heat capacity of the steam, the steam temperature at the steam inlet, and the steam temperature at the steam outlet; , is the radius of the wastewater pipe in the current heat exchanger;

[0216] Step 415: When the heat exchange satisfaction value of the main heat exchanger is less than 1, the number of auxiliary heat exchangers that need to be operated is determined based on steps 411, 412, and 413, and valve 1 of the last auxiliary heat exchanger that needs to be operated is closed and valve 2 is opened, and valve 1 of the other auxiliary heat exchangers that need to be operated is opened and valve 2 is closed. The actual flow rate of the wastewater to be evaporated entering the main heat exchanger is the target flow rate. ;

[0217] Based on the heat exchange efficiency model, the heat exchange satisfaction value of each auxiliary heat exchanger is calculated in turn until the heat exchange satisfaction value is greater than or equal to 1. Then the auxiliary heat exchanger corresponding to the heat exchange satisfaction value greater than or equal to 1 and the main heat exchanger and auxiliary heat exchanger calculated before it need to be operated.

[0218] The beneficial effects of the above technical solution are:

[0219] By collecting steam parameters, initial wastewater temperature, actual heat transfer efficiency, and flow rate efficiency (step 411), the solution comprehensively correlates the state parameters of the hot fluid (steam) and the cold fluid (wastewater). For example, steam temperature and wastewater temperature before entering the heat exchanger serve as basic inputs, combined with the heat exchanger's actual heat transfer efficiency (reflecting equipment attenuation) and flow rate efficiency (reflecting flow channel conditions), achieving "full parameter perception" of the heat exchange process. This multi-dimensional collaboration elevates heat transfer efficiency from "empirical judgment" to "data quantification," ensuring that the temperature and flow rate of the wastewater entering the evaporation device precisely match the target parameters (step 412).

[0220] Based on the wastewater flow rate-theoretical heat exchange efficiency curve (step 413), the solution can predict the theoretical heat exchange efficiency based on the actual flow rate. For example, when the wastewater flow rate changes, the theoretical efficiency is quickly inferred from the curve. Combined with steam parameters, the "heat exchange satisfaction value" is calculated to dynamically determine whether to activate the auxiliary heat exchanger. This dynamic adaptation allows the system to accurately respond to fluctuations in wastewater and steam temperatures, ensuring stable wastewater parameters after heat exchange.

[0221] The design incorporates a "primary primary heat exchanger, supplemented by auxiliary heat exchangers as needed" logic (steps 414 / 415): Auxiliary heat exchangers are gradually activated only when the primary heat exchanger's heat transfer efficiency is insufficient (satisfying a coefficient < 1). Compared to the traditional "full auxiliary heat exchanger activation" model, this reduces steam consumption (no additional steam is required for auxiliary equipment when the primary heat exchanger is fully loaded). For example, under low-load conditions, the primary heat exchanger can operate independently to meet demand, improving steam utilization.

[0222] The solution calculates the "target inlet flow rate" (step 412) and, through the heat exchange efficiency model (step 414), deeply couples wastewater flow rate with heat exchange efficiency. For example, when the actual efficiency of the main heat exchanger decreases, the wastewater flow rate can be increased to compensate for heat exchange capacity before adding an auxiliary heat exchanger, rather than adjusting steam parameters. This is particularly applicable to addressing instability in the secondary steam of an MVR evaporation and salt precipitation unit (the secondary steam from the MVR evaporation and salt precipitation unit enters the heat exchange unit for heat exchange).

[0223] The solution introduces periodic updates (step 411) of the actual heat exchange efficiency, actual wastewater flow rate efficiency, and the wastewater flow rate efficiency at the wastewater inlet of the auxiliary heat exchanger and the wastewater outlet of the previous heat exchanger. This allows real-time monitoring of heat exchanger and pipeline performance degradation caused by scaling and wear. For example, scaling during heat exchanger operation can reduce actual heat exchange efficiency. The system automatically adjusts the flow rate or activates the auxiliary heat exchanger based on coefficient calculations to compensate for the reduced heat exchange capacity caused by equipment degradation, ensuring long-term stable system operation (preventing uncontrolled evaporation unit feed parameters due to equipment aging).

[0224] Whether it is a change in wastewater type, fluctuation in wastewater temperature, or change in steam parameters, the solution is adaptively compatible with multiple working conditions through a closed loop of "dynamic calculation of target parameters - on-demand commissioning of heat exchangers - precise control of flow rate".

[0225] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A high-salt wastewater recovery and treatment process, characterized by: include: Step 1: Analyze the composition of organic matter in each high-salt wastewater to determine the composition and content of the materials in the wastewater; Step 2: Develop corresponding treatment plans for the specific components in each high-salt wastewater; Step 3: Treat the high-salinity wastewater according to the treatment plan, and adjust and optimize the plan to remove organic matter in the high-salinity wastewater and reduce the chroma of the high-salinity wastewater; Step 4: Evaporating and precipitating the qualified wastewater to prepare qualified by-product salt or by-product sodium sulfite.

2. The high-salt wastewater recovery process according to claim 1, characterized in that: The high-salt wastewater is quizalofop-ethyl cyclization-acidification wastewater, and the treatment process of the quizalofop-ethyl cyclization-acidification wastewater sequentially comprises: Step 301: adding liquid alkali to the quizalofop-ethyl cyclization acidification wastewater to adjust the pH value to a certain value; Step 302: adding hydrogen peroxide and heating to a certain temperature, and then keeping the temperature to react; Step 303: After the reaction is completed, liquid alkali is added for neutralization, and the residue is filtered and removed; Step 304: Add activated carbon to the filtrate for decolorization and filtration; The filtrate obtained in step 4 and step 304 is subjected to MVR evaporation and salt precipitation, and the obtained crude wet salt is then added with saturated salt water at room temperature for pulping and centrifugation to obtain the final by-product wet salt; The filtered waste residue is sent to a qualified unit for treatment, the mother liquor is evaporated and concentrated to remove the "three wastes" for biochemical treatment, and the mother liquor is pulped and centrifuged and applied to evaporation and salt precipitation.

3. The high-salt wastewater recovery process according to claim 1, characterized in that: The high-salt wastewater is DHPPA secondary acidification wastewater, and the treatment process of the DHPPA secondary acidification wastewater includes: Step 311: After the DHPPA secondary acidification wastewater is adsorbed by the resin, liquid alkali is added for neutralization; Step 312: After the resin is regenerated, the wastewater obtained in step 311 is transferred to the resin again for secondary adsorption and decolorization. The resin after decolorization and adsorption does not need to be regenerated and can be directly used for resin adsorption of the next batch of wastewater; In step 4, the decolorized effluent obtained in step 3 is subjected to MVR evaporation and salt precipitation to obtain by-product wet salt; The evaporated concentrated mother liquor is combined with the DHPPA secondary acidification wastewater and then subjected to resin adsorption treatment; The resin regeneration process includes: first adding water for pre-washing, then methanol decomposition and water decomposition, biochemical treatment of the pre-wash water, combining the decomposed methanol with the decomposed water, adding liquid alkali for neutralization and then distilling to recover the methanol, recovering the methanol and applying it to methanol decomposition, and sending the distillation kettle residue to a qualified unit for treatment.

4. The high-salt wastewater recovery process according to claim 1, characterized in that: The high-salt wastewater is nicotine wastewater; When the nicotine wastewater is nicotine monoamination wastewater, the treatment process of the nicotine monoamination wastewater sequentially includes: Step 321: adding liquid caustic soda to the nicotine monoamination wastewater, raising the temperature to reflux, and absorbing the dimethylamine tail gas generated by the reflux into secondary water to produce a dimethylamine aqueous solution; Step 322: The wastewater after ammonia removal is neutralized and then distilled to remove light components, which are used as biochemical carbon sources. The wastewater after light components are filtered and then subjected to resin adsorption; In step 4, the adsorbed water obtained in step 3 is subjected to MVR evaporation and salt precipitation to obtain by-product salt; Evaporation and concentration of the mother liquor is applied to the resin for adsorption; The resin regeneration process includes: first adding water for pre-washing, then methanol desorption and water desorption, pre-washing water debiochemical treatment, desorption methanol and desorption water are combined and then distilled to recover methanol, the recovered methanol is applied to methanol desorption, and the distillation kettle residue is sent to a qualified unit for treatment; When the nicotine wastewater is diamination wastewater from nicotine, the treatment process of the diamination wastewater from nicotine sequentially includes: Step 331: adding liquid caustic soda to the diamination wastewater from nicotine, raising the temperature to reflux, and absorbing the ammonia gas generated by the reflux into ammonia water; Step 332: The wastewater after ammonia removal is acidified, filtered, and then subjected to resin adsorption; Step 333: Liquid alkali is added to neutralize the adsorbed water, and after the resin regeneration is completed, the resin is adsorbed and decolorized again. The resin after decolorization and adsorption does not need to be regenerated and can be directly used for the next batch of wastewater resin adsorption; In step 4, the decolorized wastewater obtained in step 3 is evaporated and salt is precipitated to obtain by-product salt; Evaporation and concentration of the mother liquor is applied to the resin for adsorption; The resin regeneration process includes: first adding water for pre-washing, then methanol desorption and water desorption, biochemical treatment of pre-wash water, combining desorption methanol with desorption water, adding liquid alkali for neutralization and then distilling to recover methanol, recovering methanol and applying it to methanol desorption, and sending the distillation kettle residue to a qualified unit for treatment; When the nicotine wastewater is triacetone wastewater in nicotine, the treatment process of the triacetone wastewater in nicotine sequentially includes: Step 341: removing light components from triacetone wastewater in nicotine, and using the light components as a biochemical carbon source; Step 342: The wastewater from which the light components have been removed is filtered and then subjected to resin adsorption; In step 4, the adsorbed water obtained in step 3 is evaporated to separate out salt to obtain by-product salt; Evaporation and concentration of the mother liquor is applied to the resin for adsorption; The resin regeneration process includes: first adding water for pre-washing, then performing methanol decomposition and water decomposition, removing the biochemical treatment of the pre-washing water, combining the decomposed methanol with the decomposed water and then distilling to recover the methanol, and applying the recovered methanol to methanol decomposition. The residue from the distillation kettle is sent to a qualified unit for treatment.

5. The high-salt wastewater recovery process according to claim 1, characterized in that: When the high-salt wastewater is sodium sulfite wastewater, the treatment process of the sodium sulfite wastewater includes: Step 351: adding liquid caustic soda to the sodium sulfite wastewater to adjust the pH to a certain value, and filtering; Step 352: The filtrate is heated and distilled under negative pressure to be concentrated to a certain multiple, and then discharged and centrifuged at a certain temperature to obtain wet sodium sulfite salt as a by-product; The filter residue is sent to a qualified unit for treatment; the evaporated and concentrated mother liquor is reused for evaporation and salt precipitation.

6. The high-salt wastewater recovery and treatment process according to claim 1, characterized in that: The treatment scheme includes resin adsorption, which is performed based on a resin separation device; During the resin adsorption process, a resin separation status evaluation process is performed periodically; During each resin separation status assessment process, the wastewater flow rate at the wastewater inlet of the resin separation device, the wastewater flow rate on the resin inlet side of the resin separation device, and the wastewater flow rate on the resin outlet side of the resin separation device are detected, as well as the flow rate at the outlet of the wastewater outlet valve of the resin separation device at the current valve opening; and determining a first ratio of an average value of the wastewater flow rate at the resin outlet side to an average value of the wastewater flow rate at the resin inlet side corresponding to each resin separation state evaluation process; Based on each resin separation status evaluation process, the wastewater retention coefficient is determined by the average value of the flow rate of the corresponding wastewater outlet valve at the current valve opening and the average value of the wastewater flow rate at the wastewater inlet; and determining a valve flow rate loss coefficient when the first ratio is greater than a first preset value; When any one of the following occurs: the first ratio is less than or equal to the first preset value, or the valve flow rate loss coefficient is greater than the preset loss coefficient, the control alarm device 1 is controlled to issue an early warning.

7. The high-salt wastewater recovery process according to claim 6, characterized in that: The resin adsorption process for the current wastewater to be adsorbed includes: Step 301: When the alarm is not sounding, the valve flow rate loss coefficients obtained from the latest several resin separation status evaluation processes are obtained, a time-valve loss coefficient variation curve is constructed, the required flow rate range of the current wastewater to be adsorbed passing through the valve outlet of the resin separation device is obtained, and a valve opening-standard flow rate variation curve corresponding to the current wastewater to be adsorbed is obtained; the valve is not cleaned during the time period corresponding to each time-valve loss coefficient variation curve; Step 302: Based on the selected flow rates selected according to a predetermined rule within the required flow rate range and the time-valve loss coefficient variation curve obtained in step 301, determine the current predicted retention coefficient corresponding to each selected flow rate; Step 303: Obtaining a curve of the standard flow rate range of the wastewater and the resin adsorption effect evaluation value under the corresponding standard conditions for the current wastewater to be adsorbed; Step 304: Determine a comprehensive evaluation value for each selected flow rate based on the current predicted retention coefficient corresponding to each selected flow rate determined in step 303, the first ratio determined in the latest resin separation state evaluation process, and a curve of the standard flow rate range of wastewater and the resin adsorption effect evaluation value; Step 305: Determine the average of N selected flow rates with the largest comprehensive evaluation values ​​and a comprehensive evaluation value greater than a preset evaluation value as the first flow rate, and determine the target valve opening corresponding to the valve opening corresponding to the current wastewater to be adsorbed-standard flow rate change curve of the first flow rate; Step 306: Adjust the actual valve opening of the valve to the target valve opening, and set the actual water inlet flow rate to the corresponding rated water inlet flow rate for the current wastewater to be adsorbed, and perform resin adsorption on the current wastewater to be adsorbed until the valve opening adjustment condition is met.

8. The high-salt wastewater recovery and treatment process according to claim 7, characterized in that: The conditions for adjusting the valve opening are: the difference between the first ratio determined in step 302 and the first ratio determined in the subsequent resin separation state evaluation process is greater than a first preset difference, the difference between the valve loss coefficient determined in the subsequent resin separation state evaluation process and the valve loss coefficient determined in step 302 is greater than a second preset difference, or the type of wastewater to be adsorbed changes.

9. The high-salt wastewater recovery and treatment process according to claim 1, characterized in that: The step 4 comprises: Step 41: pre-treating the qualified wastewater by heating; Step 42: Inputting the wastewater after heating pretreatment into an evaporation device for evaporation; Step 41 is performed based on a heat exchange device, which includes: a main heat exchanger and several auxiliary heat exchangers arranged in sequence, wherein the wastewater outlet of the preceding heat exchanger is connected to the wastewater inlet of the succeeding heat exchanger through a first pipe, a branch pipe is fixedly connected to the middle of the first pipe, a second valve is provided on the branch pipe, a first valve is provided on the first pipe near the wastewater inlet of the succeeding heat exchanger, the branch pipe is connected to a second pipe, and the second pipe is connected to the wastewater inlet of the evaporation device, and the main heat exchanger and the several auxiliary heat exchangers are all connected to a steam inlet pipe; when the first valve and the second valve are in operation, they operate at the corresponding rated opening; During use, each heat exchanger performs a heat exchange state evaluation process for a second time period every first time period. The current heat exchange state evaluation process includes: Determining, based on the detection, within the current second time period, operating status evaluation parameters, the operating status evaluation parameters including: actual heat exchange efficiency and actual wastewater flow rate efficiency of the operating heat exchanger, and wastewater flow rate efficiency between the wastewater inlet of the operating auxiliary heat exchanger and the wastewater outlet of the previous operating heat exchanger; When any of the operating status evaluation parameters is out of the corresponding preset range, an alarm is sounded through the second alarm.

10. The high-salt wastewater recovery and treatment process according to claim 9, characterized in that: The step 41 includes: Step 411: obtaining the current steam parameters of the steam inlet pipe and the current temperature of the wastewater to be evaporated before entering the main heat exchanger, and obtaining the latest determined operating status evaluation parameters; Step 412: Obtain target heat exchange parameters for the current type of wastewater to be evaporated, and determine a target inlet flow rate of the current type of wastewater to be evaporated into the main heat exchanger based on the target heat exchange parameters and step 411. The target heat exchange parameters include: a target temperature entering the evaporation device and a target flow rate range entering the evaporation device; Step 413: Obtain a curve of wastewater flow rate-theoretical heat exchange efficiency change of the current type of wastewater to be evaporated in each heat exchanger; Step 414: Based on steps 411, 412, and 413, the heat exchange satisfaction value of the main heat exchanger is first determined. When the heat exchange satisfaction value of the main heat exchanger is greater than or equal to 1, the actual flow rate of the wastewater inlet of the main heat exchanger is controlled to be the target inlet flow rate, valve 1 corresponding to the main heat exchanger is controlled to be closed and valve 2 is controlled to be opened, and valves 1 and 2 corresponding to all auxiliary heat exchangers are controlled to be closed, thereby achieving heat exchange for the current wastewater to be evaporated; Step 415: When the heat exchange satisfaction value of the main heat exchanger is less than 1, the number of auxiliary heat exchangers that need to be operated is determined based on steps 411, 412, and 413, and valve 1 of the last auxiliary heat exchanger that needs to be operated is controlled to be closed and valve 2 is controlled to be opened, and valve 1 of the other auxiliary heat exchangers that need to be operated is controlled to be opened and valve 2 is controlled to be closed.

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