Pendimethalin process wastewater decoking process

Abstract

The present application relates to the field of water pollution control and treatment, and discloses a kind of pyridate process wastewater defocusing process, comprising the following steps: step 1, inorganic crystal nucleus inducer and modified sodium lignosulfonate are added to pyridate synthesis coke wastewater;Step 2, add alkali regulator to the mixed system after step 1 treatment;Step 3, add backflow sludge to the mixed solution of step 2, and open ultrasonic treatment at the same time;Step 4, calculate the lattice energy dissipation index according to the acoustic impedance change of multiphase fluid;Then combine the clarity and conductivity of water sample, adjust the addition rate of crystal nucleus agent and alkali regulator;Step 5, co-sedimentation separation is carried out through solid-liquid separation equipment, the present application uses inorganic solid phase lattice to harden the space confinement of organic coke, to block its thermal adhesion activity, solves the technical contradiction between the defocusing efficiency improvement and equipment pollution, eliminates the equipment surface coke scale and improves the settling velocity.

Description

Technical Field

[0001] This invention belongs to the field of water pollution control and treatment technology, and particularly relates to a coke removal process for wastewater from dimethyl pendimethalin process. Background Technology

[0002] Current solid-liquid separation methods generally employ inorganic component coagulation combined with acid-base adjustment. By controlling the surface charge of the wastewater system, emulsified and dissolved pollutants undergo molecular aggregation, transforming liquid pollutants into solid sludge that can be settled by gravity or mechanically intercepted, thus reducing the organic fouling load on subsequent biological or membrane separation units. However, for high-salt, high-viscosity organic coke wastewater generated from dimethylpentylamine synthesis, the polynitroaniline condensates and unsaturated hydrocarbon tar in the wastewater have a wide phase transition temperature range and strong wetting and adhesion capabilities at the solid-liquid interface. Traditional charge neutralization processes easily cause disordered aggregation and homogeneous nucleation of high-viscosity liquid coke, generating highly plastic amorphous coke scale. This scale adheres extensively to the inner walls of transfer pumps, reaction channels, and heat exchange pipelines, resulting in decreased heat exchange efficiency, reduced channel diameter, and scaling and contamination of detection sensors. Ultimately, the system requires frequent shutdowns for coke removal.

[0003] Besides the limitations of the equipment and reagents themselves, existing multi-stage deep physicochemical control schemes also have shortcomings. For example, the o-nitroaniline wastewater treatment process disclosed in CN120794241A uses flocculation followed by magnetic activated carbon adsorption, then series oxidation and macroporous resin adsorption; this scheme is not suitable for dimethylpentylamine synthesis wastewater. Strongly adhesive high-molecular-weight polynitroaniline condensates in the wastewater quickly coat and clog the activated carbon and resin micropores, causing adsorption site failure and equipment scaling. This process lacks in-situ lattice locking of the wetting activity of organic tar within the phase transition range, making continuous anti-clogging operation difficult when dealing with high-viscosity, high-salt wastewater affected by the common ion effect, resulting in high treatment and media regeneration costs.

[0004] Conventional improvement methods involve increasing the coagulant dosage or enhancing the shear field; however, in near-saturated inorganic salt systems, excessive dosage can trigger the common ion effect, causing premature spontaneous crystallization of inorganic salts. This not only fails to inhibit the wetting and adhesion of viscous coke to the equipment walls but also forms an interwoven scale layer of inorganic crystals and plastic coke, exacerbating scaling. To regulate the solid-liquid interface wettability of high-viscosity organic coke in multiphase flow systems, eliminate its surface adhesion activity, avoid multi-signal interference from high-salt complex operating conditions on dosing feedback control, achieve efficient coke removal, and ensure the anti-fouling and continuous stable operation of the water treatment system, we propose a coke removal process using pendimethalin. Summary of the Invention

[0005] This invention aims to solve the problems of strong adhesion and clogging of heat exchange pipelines at the solid-liquid interface of highly viscous organic coke, as well as the distortion of dosing control signals caused by complex, high-salt, and variable operating conditions.

[0006] In this technical solution, a coke removal process for wastewater from a dimethyl pendimethalin process includes the following steps:

[0007] Step 1: Add inorganic nucleation inducer and modified sodium lignosulfonate to the dimethylpentylene synthesis coke wastewater. Under acidic conditions, the modified sodium lignosulfonate is adsorbed on the surface of the online test probe to form a protective layer.

[0008] Step 2: Add an alkali adjuster to the mixed system after Step 1 to adjust its pH value to 8.8 to 9.5;

[0009] Step 3: Add refluxed sludge to the mixture from Step 2, and simultaneously turn on ultrasonic treatment at a frequency of 25-40 kHz and a sound energy density of 0.4-0.8 W / cm².

[0010] Step 4: Calculate the lattice energy dissipation index based on the change in acoustic impedance of ultrasound in the multiphase fluid. When the index is less than 0.35, switch the ultrasound to a pulse mode with a duty cycle of 1:2. Then, in combination with the water sample clarity and conductivity, adjust the dosing rate of nucleating agent and alkali regulator simultaneously to keep the total amount of solids in the system within the set range.

[0011] Step 5: Co-sedimentation separation is carried out using a solid-liquid separation device to remove crystals adsorbed with organic coke.

[0012] Preferably, in step 4, the lattice energy dissipation index is calculated based on the acoustic impedance change rate of ultrasonic cavitation in the multiphase fluid. When the index is less than 0.35, the ultrasound switches from continuous operation to a pulse mode with a duty cycle of 1:2 to break through the viscous barrier and achieve crystal encapsulation precipitation.

[0013] Preferably, step 1 includes the following sub-steps: Step 11: continuously feeding the coke wastewater generated from the synthesis of dimethylpentylamine into a mixed-phase reactor and adjusting the pH of the system to 1.8-2.4; Step 12: adding an inorganic nucleation inducer to the reactor, with the volume ratio of the inducer to wastewater controlled at 0.003:1-0.006:1, so that inorganic nucleation precursors with rough surfaces precipitate out of the wastewater.

[0014] Preferably, step 2 includes the following sub-steps: step 21: send the mixture after step 1 into a hardening reactor, add an alkaline regulator, and adjust the pH of the system to 8.8-9.5; step 22: allow inorganic salts to nucleate and crystallize on the surface of inorganic crystal precursors, and encapsulate organic coke molecules through crystallization.

[0015] Preferably, in step 1, the inorganic nucleation inducer is a 15% (w / w) aluminum ammonium sulfate solution, and 0.02% (w / w) of modified sodium lignosulfonate is pre-doped into the inorganic nucleation inducer.

[0016] Preferably, the method further includes step 6, which involves adding the returned sludge discharged from the solid-liquid separation equipment into the mixing system of step 1 through the returned pipeline, and controlling the volume ratio of the returned sludge to the dimethylpentylamine synthetic coke wastewater to be 0.05:1 to 0.12:1.

[0017] Preferably, step 6 includes the following sub-steps: Step 61: Detect the density and flow rate of the sludge slurry using a differential pressure sensor in the return pipe, and calculate the effective specific surface area factor of the seed crystals; Step 62: If the factor is lower than 1.25, open the clean water flushing valve and increase the dosage ratio of the inorganic crystal nucleation inducer in S1 by 15%.

[0018] Preferably, in steps 1 to 5, the reaction temperature of the mixing system is controlled to be stable at 40°C to 60°C.

[0019] Compared with existing technologies, the dimethylpentylamine process wastewater coking removal technology of the present invention has the following advantages:

[0020] 1. First, the wastewater from the dimethylpentylamine process is adjusted to the acidic metastable region, precipitating inorganic crystal nuclei precursors with rough surfaces. Subsequently, the alkalinity is adjusted in reverse, and the emulsified organic tar is demulsified and directionally adsorbed as it drifts with its isoelectric point. As the alkalinity increases, the precursor undergoes in-situ crystalline phase transformation to form a dense three-dimensional lattice network of amphoteric metal hydroxides. Through spatial confinement and entrainment, the highly active groups of the viscous organic condensate are sealed in the crystal micro-regions. This cuts off the wetting path of the organic tar on the equipment wall, reduces thermal adhesion on the surface of the conveying and heat exchange equipment, and obtains high-density composite crystalline particles that can settle by gravity.

[0021] 2. A fluid shear damping structure with staggered silicon carbide limiting grids is installed in the pre-drainage channel. The high-viscosity emulsified coke is broken into small-diameter droplets through mechanical shearing, which increases the specific surface area of ​​organic unsaturated hydrocarbons and reduces the heterogeneous nucleation capture threshold. A low dose of modified sodium lignin sulfonate structure stabilizing factor is pre-added to the inorganic nucleation inducer. Under acidic conditions, it selectively adsorbs on the surface of the online probe to form a dynamic hydration hydrophilic oil-removing layer, which inhibits the adhesion and scaling of coke on the probe wall and reduces the sensor signal distortion caused by operating disturbances.

[0022] 3. Online acquisition of effluent clarity index and conductivity change rate; control unit constructs dual-source differential cooperative adaptive architecture to identify interference caused by high salt fluctuations leading to common ion effect and premature precipitation of inorganic salts, avoiding misjudgment of single clarity index leading to overload of crystal nucleation inducer addition; based on the dynamic trend of the signal, the addition flow rate of crystal nucleation inducer and the droplet acceleration rate of alkaline regulator are adjusted in linkage to ensure that the effluent coke residue meets the standard and maintain the dynamic balance of total solid phase in the multiphase hardening system. Attached Figure Description

[0023] Figure 1 This is a flowchart of a method for removing coke from dimethyl pendimethalin synthetic coke wastewater according to the present invention;

[0024] Figure 2 This is a diagram of the process for removing coke from the dimethyl pendimethalin synthetic coke wastewater of the present invention. Detailed Implementation

[0025] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0026] Reference Figures 1-2 A decoking process for wastewater from a dimethyl pendimethalin process includes the following steps:

[0027] Step 1: Add inorganic nucleation inducer and modified sodium lignosulfonate to the dimethylpentylene synthesis coke wastewater. Under acidic conditions, the modified sodium lignosulfonate is adsorbed on the surface of the online test probe to form a protective layer.

[0028] Step 2: Add an alkali adjuster to the mixed system after Step 1 to adjust its pH value to 8.8 to 9.5;

[0029] Step 3: Add refluxed sludge to the mixture from Step 2, and simultaneously turn on ultrasonic treatment at a frequency of 25-40 kHz and a sound energy density of 0.4-0.8 W / cm².

[0030] Step 4: Calculate the lattice energy dissipation index based on the change in acoustic impedance of ultrasound in the multiphase fluid. When the index is less than 0.35, switch the ultrasound to a pulse mode with a duty cycle of 1:2. Then, in combination with the water sample clarity and conductivity, adjust the dosing rate of nucleating agent and alkali regulator simultaneously to keep the total amount of solids in the system within the set range.

[0031] Step 5: Co-sedimentation separation is carried out using a solid-liquid separation device to remove crystals adsorbed with organic coke.

[0032] In step 4, the lattice energy dissipation index is calculated based on the acoustic impedance change rate of ultrasonic cavitation in the multiphase fluid. When the index is less than 0.35, the ultrasound switches from continuous operation to a pulse mode with a duty cycle of 1:2 to break through the viscous barrier and achieve crystal encapsulation precipitation.

[0033] Step 1 includes the following sub-steps: Step 11: continuously feed the coke wastewater generated from the synthesis of dimethylpentylamine into a mixed-phase reactor and adjust the pH of the system to 1.8-2.4; Step 12: add an inorganic nucleation inducer to the reactor, and control the volume ratio of the inducer to the wastewater at 0.003:1-0.006:1, so that inorganic nucleation precursors with rough surfaces precipitate out of the wastewater.

[0034] Step 2 includes the following sub-steps: Step 21: The mixture after Step 1 is sent into a hardening reactor, an alkaline regulator is added, and the pH of the system is adjusted to 8.8-9.5; Step 22: Inorganic salts are nucleated and crystallized on the surface of inorganic crystal precursors, and organic coke molecules are encapsulated by crystallization.

[0035] In step 1, the inorganic nucleation inducer is a 15% (w / w) aluminum ammonium sulfate solution, and 0.02% (w / w) of modified sodium lignin sulfonate is pre-doped into the inorganic nucleation inducer.

[0036] It also includes step 6, which is as follows: the return sludge discharged from the solid-liquid separation equipment is added to the mixing system of step 1 through the return pipeline, and the volume ratio of the return sludge to the dimethyl pendimethalin synthetic coke wastewater is controlled to be 0.05:1 to 0.12:1.

[0037] Step 6 includes the following sub-steps: Step 61: Detect the density and flow rate of the sludge slurry using a differential pressure sensor in the return pipeline, and calculate the effective specific surface area factor of the seed crystals; Step 62: If the factor is lower than 1.25, open the clean water flushing valve and simultaneously increase the dosage of the inorganic nucleation inducing agent in S1 by 15%. The effective specific surface area factor is used to measure the activity of the returned sludge seed crystals, representing the relative size of the effective surface area of ​​the seed crystal particles that can actually participate in crystallization and encapsulation. A low value indicates that the seed crystals have caking, the surface is covered by contaminants, and the reactivity has decreased.

[0038] In steps 1 to 5, the reaction temperature of the mixture is controlled to be stable between 40°C and 60°C.

[0039] In the following examples, the test wastewater was taken from the dimethyl pendimethalin production line, with an initial coke concentration of 4850 mg / L, a salt content of 5.3%, a wastewater flow rate of 15-20 m³ / h, and an acidity regulator of 20%-30% industrial dilute sulfuric acid and an alkalinity regulator of 30% sodium hydroxide solution.

[0040] Example 1: A process for removing coke from wastewater from a dimethyl pendimethalin process, comprising the following steps:

[0041] Step 1 involves adding an inorganic nucleation inducer and modified sodium lignosulfonate to the coke wastewater from the dimethylpentylene synthesis process. Under acidic conditions, the modified sodium lignosulfonate is adsorbed onto the surface of the online test probe to form a protective layer. Step 1 includes the following sub-steps: Step 11: The coke wastewater generated from the dimethylpentylene synthesis process is continuously fed into a mixed-phase reactor, and the pH of the system is adjusted to 1.8. Step 12: An inorganic nucleation inducer is added to the reactor, with the volume ratio of the inducer to the wastewater controlled at 0.003:1, so that inorganic nucleation precursors with rough surfaces precipitate out of the wastewater. In Step 1, the inorganic nucleation inducer is a 15% (w / w) aluminum ammonium sulfate solution, and 0.02% (w / w) of modified sodium lignosulfonate is pre-doped into the inorganic nucleation inducer.

[0042] Step 2: Add an alkaline regulator to the mixed system after Step 1 to adjust its pH value to 8.8. Step 2 includes the following sub-steps: Step 21: Send the mixed solution after Step 1 into the hardening reactor, add an alkaline regulator, and adjust the pH of the system to 8.8; Step 22: Allow the inorganic salt to nucleate and crystallize on the surface of the inorganic crystal precursor, and encapsulate the organic coke molecules through crystallization.

[0043] Step 3: Add refluxed sludge to the mixture from Step 2, and simultaneously start ultrasonic treatment at a frequency of 25 kHz and a sound energy density of 0.4 W / cm².

[0044] Step 4: Calculate the lattice energy dissipation index based on the change in acoustic impedance of ultrasound in the multiphase fluid. When the index is less than 0.35, switch the ultrasound to a pulse mode with a duty cycle of 1:2 to break through the viscosity barrier and achieve crystal encapsulation and precipitation. Then, combine the water sample clarity and conductivity to simultaneously adjust the dosing rate of the nucleating agent and the alkali regulator to maintain the total amount of solids in the system within the set range.

[0045] Step 5: Co-sedimentation separation is carried out using a solid-liquid separation device to remove crystals adsorbed with organic coke.

[0046] In steps 1 to 5, the reaction temperature of the mixture is controlled to be stable at 40°C.

[0047] The process also includes step 6, which involves adding the returned sludge discharged from the solid-liquid separation equipment to the mixing system in step 1 via a return pipeline, controlling the volume ratio of the returned sludge to the dimethylpentylamine synthetic coke wastewater to be 0.05:1. Step 6 includes the following sub-steps: Step 61: Detect the density and flow rate of the sludge slurry using a differential pressure sensor in the return pipeline, and calculate the effective specific surface area factor of the seed crystals; Step 62: If the factor is lower than 1.25, open the clean water flushing valve and simultaneously increase the dosage ratio of the inorganic crystal nucleation inducer in S1 by 15%.

[0048] In Example 1, the coke removal rate was 99.1% and the COD removal rate was 44.1%; the solid cake after pressure filtration was non-adhesive and could be completely peeled off.

[0049] Example 2, a coke removal process for wastewater from dimethyl pendimethalin process, includes the following steps:

[0050] Step 1 involves adding an inorganic nucleation inducer and modified sodium lignosulfonate to the coke wastewater from the synthesis of dimethylpentylamine. Under acidic conditions, the modified sodium lignosulfonate is adsorbed onto the surface of the online test probe to form a protective layer. Step 1 includes the following sub-steps: Step 11: The coke wastewater generated from the synthesis of dimethylpentylamine is continuously fed into a mixed-phase reactor, and the pH of the system is adjusted to 2.4; Step 12: An inorganic nucleation inducer is added to the reactor, with the volume ratio of inducer to wastewater controlled at 0.006:1, so that inorganic nucleation precursors with rough surfaces precipitate out of the wastewater. In Step 1, the inorganic nucleation inducer is a 15% (w / w) aluminum ammonium sulfate solution, and 0.02% (w / w) of modified sodium lignosulfonate is pre-doped into the inorganic nucleation inducer.

[0051] Step 2: Add an alkaline regulator to the mixed system after Step 1 to adjust its pH value to 9.5. Step 2 includes the following sub-steps: Step 21: Send the mixed solution after Step 1 into the hardening reactor, add an alkaline regulator, and adjust the pH of the system to 9.5; Step 22: Allow the inorganic salt to nucleate and crystallize on the surface of the inorganic crystal precursor, and encapsulate the organic coke molecules through crystallization.

[0052] Step 3: Add refluxed sludge to the mixture from Step 2, and simultaneously start ultrasonic treatment at a frequency of 40kHz and a sound energy density of 0.8W / cm².

[0053] Step 4: Calculate the lattice energy dissipation index based on the change in acoustic impedance of ultrasound in the multiphase fluid. When the index is less than 0.35, switch the ultrasound to a pulse mode with a duty cycle of 1:2 to break through the viscosity barrier and achieve crystal encapsulation and precipitation. Then, combine the water sample clarity and conductivity to simultaneously adjust the dosing rate of the nucleating agent and the alkali regulator to maintain the total amount of solids in the system within the set range.

[0054] Step 5: Co-sedimentation separation is carried out using a solid-liquid separation device to remove crystals adsorbed with organic coke.

[0055] In steps 1 to 5, the reaction temperature of the mixture is controlled to be stable at 60°C.

[0056] The process also includes step 6, which involves adding the returned sludge discharged from the solid-liquid separation equipment to the mixing system in step 1 via a return pipeline, controlling the volume ratio of the returned sludge to the dimethylpentylamine synthetic coke wastewater to be 0.12:1. Step 6 includes the following sub-steps: Step 61: Detecting the density and flow rate of the sludge slurry using a differential pressure sensor in the return pipeline, and calculating the effective specific surface area factor of the seed crystals; Step 62: If the factor is lower than 1.25, opening the clean water flushing valve and simultaneously increasing the dosage ratio of the inorganic crystal nucleation inducer in S1 by 15%.

[0057] In Example 2, the coke removal rate was 99.3% and the COD removal rate was 45.9%; the solid cake after pressure filtration was free of adhesion and could be completely peeled off.

[0058] Example 3, a decoking process for wastewater from dimethyl pendimethalin process, includes the following steps:

[0059] Step 1 involves adding an inorganic nucleation inducer and modified sodium lignosulfonate to the coke wastewater from the synthesis of dimethylpentylamine. Under acidic conditions, the modified sodium lignosulfonate is adsorbed onto the surface of the online test probe to form a protective layer. Step 1 includes the following sub-steps: Step 11: The coke wastewater generated from the synthesis of dimethylpentylamine is continuously fed into a mixed-phase reactor, and the pH of the system is adjusted to 2.1; Step 12: An inorganic nucleation inducer is added to the reactor, with the volume ratio of inducer to wastewater controlled at 0.004:1, so that inorganic nucleation precursors with rough surfaces precipitate out of the wastewater. In Step 1, the inorganic nucleation inducer is a 15% (w / w) aluminum ammonium sulfate solution, and 0.02% (w / w) of modified sodium lignosulfonate is pre-doped into the inorganic nucleation inducer.

[0060] Step 2: Add an alkaline regulator to the mixed system after Step 1 to adjust its pH value to 9.0. Step 2 includes the following sub-steps: Step 21: Send the mixed solution after Step 1 into the hardening reactor, add an alkaline regulator, and adjust the pH of the system to 9.0; Step 22: Allow the inorganic salt to nucleate and crystallize on the surface of the inorganic crystal precursor, and encapsulate the organic coke molecules through crystallization.

[0061] Step 3: Add refluxed sludge to the mixture from Step 2, and simultaneously start ultrasonic treatment at a frequency of 30kHz and a sound energy density of 0.6W / cm².

[0062] Step 4: Calculate the lattice energy dissipation index based on the change in acoustic impedance of ultrasound in the multiphase fluid. When the index is less than 0.35, switch the ultrasound to a pulse mode with a duty cycle of 1:2 to break through the viscosity barrier and achieve crystal encapsulation and precipitation. Then, combine the water sample clarity and conductivity to simultaneously adjust the dosing rate of the nucleating agent and the alkali regulator to maintain the total amount of solids in the system within the set range.

[0063] Step 5: Co-sedimentation separation is carried out using a solid-liquid separation device to remove crystals adsorbed with organic coke.

[0064] In steps 1 to 5, the reaction temperature of the mixture is controlled to be stable at 50°C.

[0065] The process also includes step 6, which involves adding the returned sludge discharged from the solid-liquid separation equipment to the mixing system in step 1 via a return pipeline, controlling the volume ratio of the returned sludge to the dimethylpentylamine synthetic coke wastewater to be 0.08:1. Step 6 includes the following sub-steps: Step 61: Detect the density and flow rate of the sludge slurry using a differential pressure sensor in the return pipeline, and calculate the effective specific surface area factor of the seed crystals; Step 62: If the factor is lower than 1.25, open the clean water flushing valve and simultaneously increase the dosage ratio of the inorganic crystal nucleation inducer in S1 by 15%.

[0066] In Example 3, the coke removal rate was 99.3% and the COD removal rate was 49.8%; the solid cake after pressure filtration was free of adhesion and could be completely peeled off.

[0067] In Examples 1-3, the residual coke in the effluent is ≤20mg / L; the scaling rate of equipment and pipelines is reduced by more than 95%; the unplanned descaling shutdown cycle is extended from 48 hours to more than 720 hours, and long-term continuous and stable operation is possible.

[0068] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit of this application and the scope of protection of this invention, and all of these forms are within the protection scope of this application.

Claims

1. A process for removing coke from wastewater from a dimethyl pendimethalin process, characterized in that, Includes the following steps: Step 1: Add inorganic nucleation inducer and modified sodium lignosulfonate to the dimethylpentylene synthesis coke wastewater. Under acidic conditions, the modified sodium lignosulfonate is adsorbed on the surface of the online test probe to form a protective layer. Step 2: Add an alkali adjuster to the mixed system after Step 1 to adjust its pH value to 8.8 to 9.5; Step 3: Add refluxed sludge to the mixture from Step 2, and simultaneously perform ultrasonic treatment at a frequency of 25–40 kHz and a sound energy density of 0.4–0.8 W / cm³. 2 ; Step 4: Calculate the lattice energy dissipation index based on the change in acoustic impedance of ultrasound in the multiphase fluid. When the index is less than 0.35, switch the ultrasound to a pulse mode with a duty cycle of 1:

2. Then, in combination with the water sample clarity and conductivity, adjust the dosing rate of nucleating agent and alkali regulator simultaneously to keep the total amount of solids in the system within the set range. Step 5: Co-sedimentation separation is carried out using a solid-liquid separation device to remove crystals adsorbed with organic coke.

2. The decoking process for wastewater from the dimethylpentylene process according to claim 1, characterized in that, In step 4, the lattice energy dissipation index is calculated based on the acoustic impedance change rate of ultrasonic cavitation in the multiphase fluid. When the index is less than 0.35, the ultrasound switches from continuous operation to a pulse mode with a duty cycle of 1:2 to break through the viscous barrier and achieve crystal encapsulation precipitation.

3. The decoking process for wastewater from the dimethylpentylene process according to claim 1, characterized in that, Step 1 includes the following sub-steps: Step 11: continuously feed the coke wastewater generated from the synthesis of dimethylpentylamine into a mixed-phase reactor and adjust the pH of the system to 1.8-2.4; Step 12: add an inorganic nucleation inducer to the reactor, and control the volume ratio of the inducer to the wastewater at 0.003:1-0.006:1, so that inorganic nucleation precursors with rough surfaces precipitate out of the wastewater.

4. The decoking process for dimethyl pendimethalin process wastewater according to claim 1, characterized in that, Step 2 includes the following sub-steps: Step 21: The mixture after Step 1 is sent into a hardening reactor, an alkaline regulator is added, and the pH of the system is adjusted to 8.8-9.5; Step 22: Inorganic salts are nucleated and crystallized on the surface of inorganic crystal precursors, and organic coke molecules are encapsulated by crystallization.

5. The decoking process for dimethyl pendimethalin process wastewater according to claim 1, characterized in that, In step 1, the inorganic nucleation inducer is a 15% (w / w) aluminum ammonium sulfate solution, and 0.02% (w / w) of modified sodium lignin sulfonate is pre-doped into the inorganic nucleation inducer.

6. The decoking process for wastewater from the dimethylpentylene process according to claim 1, characterized in that, It also includes step 6, which is as follows: the return sludge discharged from the solid-liquid separation equipment is added to the mixing system of step 1 through the return pipeline, and the volume ratio of the return sludge to the dimethyl pendimethalin synthetic coke wastewater is controlled to be 0.05:1 to 0.12:

1.

7. The dimethylpentylene process wastewater decoking process according to claim 6, characterized in that, Step 6 includes the following sub-steps: Step 61: Detect the density and flow rate of the sludge slurry using the differential pressure sensor in the return pipe, and calculate the effective specific surface area factor of the seed crystals; Step 62: If the factor is lower than 1.25, open the clean water flushing valve and increase the dosage ratio of the inorganic crystal nucleation inducer in S1 by 15%.

8. The decoking process for dimethyl pendimethalin process wastewater according to claim 1, characterized in that, In steps 1 to 5, the reaction temperature of the mixture is controlled to be stable between 40°C and 60°C.

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