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CN-121990676-A - Printing and dyeing wastewater three-phase catalytic oxidation treatment system

CN121990676ACN 121990676 ACN121990676 ACN 121990676ACN-121990676-A

Abstract

The invention discloses a printing and dyeing wastewater three-phase catalytic oxidation treatment system, belongs to the technical field of wastewater treatment, and solves the problems of wastewater treatment by ozone catalysis, monitoring and missing trace toxic byproducts and metal leaching, poisoning water and ozone consumption, acidification deactivation circulation and silent collapse of the system. The multi-phase catalytic oxidation reactor comprises a pulse electrolysis pretreatment unit, a multi-phase catalytic oxidation main reactor and a control unit, wherein the pulse electrolysis pretreatment unit is used for decomposing pollutants through pulse electrolysis oxidation and adjusting current and duty ratio according to catalyst health degree and bromide ion concentration. The method reduces bromide ions through pulse electrolysis, utilizes on-line metal monitoring to dynamically regulate and control the reaction environment to prevent the catalyst from collapsing, combines biological toxicity real-time early warning as final decision, and enables the whole treatment process to be capable of perceiving and breaking the vicious circle of toxicity generation and catalyst failure in advance, thereby ensuring long-term safety and stability of effluent.

Inventors

  • CHEN FEIYU
  • YANG LIFENG
  • LIU YINHAI
  • SONG HUALONG
  • ZHU CHAOGANG
  • CHEN WEI

Assignees

  • 绍兴水处理发展有限公司

Dates

Publication Date
20260508
Application Date
20260204

Claims (7)

  1. 1. A three-phase catalytic oxidation treatment system for printing and dyeing wastewater is characterized by comprising A pulse electrolysis pretreatment unit (1) for decomposing pollutants by pulse electrolysis oxidation and adjusting the current and the duty ratio according to the catalyst health degree and the bromide ion concentration; the heterogeneous catalytic oxidation main reactor (2) is used for catalyzing ozone to generate hydroxyl radical oxidation pollutants by using a supported catalyst and dynamically optimizing the ozone addition amount, the pH value and the oxidation-reduction potential according to the oxidation efficiency and the toxicity risk which are evaluated in real time; the gas-liquid separation and ozone recycling unit (3) is used for performing gas-liquid separation on the reaction tail gas and recycling the tail gas containing ozone to the ozone generator after compression and drying; the on-line metal ion monitoring and adsorbing enrichment unit (5) is used for monitoring the concentration of leached catalyst metal ions in the effluent in real time and selectively adsorbing and enriching when the concentration exceeds the standard; the tail end biotoxicity online early warning unit (4) is used for evaluating the biotoxicity of water by using online behavioral monitoring of aquatic organisms as a supplement and final safety criterion of traditional chemical index monitoring; the central intelligent control unit (6) is used for executing multi-source data fusion, risk real-time calculation, multi-unit cooperative regulation and control, safety decision and self-learning algorithm and overall coordination of the work of each unit; The device comprises a pulse electrolysis pretreatment unit (1), a heterogeneous catalytic oxidation main reactor (2), a gas-liquid separation and ozone recycling unit (3) and a tail end biotoxicity online early warning unit (4), wherein the pulse electrolysis pretreatment unit, the heterogeneous catalytic oxidation main reactor, the gas-liquid separation and ozone recycling unit and the tail end biotoxicity online early warning unit (4) are sequentially connected through pipelines, sampling ports of an online metal ion monitoring and adsorption enrichment unit (5) are connected in parallel to a water outlet pipeline of the heterogeneous catalytic oxidation main reactor (2), and a central intelligent control unit (6) is connected with other units through a communication bus.
  2. 2. The three-phase catalytic oxidation treatment system for printing and dyeing wastewater according to claim 1, wherein the pulse electrolysis pretreatment unit (1) comprises an anti-corrosion electrolytic tank body, a high-frequency pulse power supply and a digital signal processor, wherein a water outlet of the anti-corrosion electrolytic tank body is connected with a water inlet of a multi-phase catalytic oxidation main reactor (2) through a pipeline, a first electrode plate group and a second electrode plate group are alternately arranged in the anti-corrosion electrolytic tank body in parallel along the vertical direction, the first electrode plate group is formed by connecting a plurality of titanium-based mixed metal oxide coating net anode plates in series through a first titanium-copper composite conductive rod, the second electrode plate group is formed by connecting a plurality of stainless steel perforated cathode plates in series through a second titanium-copper composite conductive rod, the first and second titanium copper composite conductive bars are fixed on and penetrate through the side wall of the anticorrosion electrolytic tank body through insulating sealing sleeves, the anticorrosion electrolytic tank body is fixedly connected with a tubular anion exchange membrane component positioned in the fluid downstream direction of the second electrode plate group and at a preset distance from the second electrode plate group, the direct current positive power output end of the high-frequency pulse power supply is connected to the extending end of the first titanium copper composite conductive bar outside the tank body through a first power cable, the direct current negative power output end of the high-frequency pulse power supply is connected to the extending end of the second titanium copper composite conductive bar outside the anticorrosion electrolytic tank body through a second power cable, each driving signal input pin of the insulated gate bipolar transistor driving plate inside the high-frequency pulse power supply is connected to a corresponding enhanced pulse width modulation signal output pin on the digital signal processor through a flat cable, the digital signal processor is connected to the network of the central intelligent control unit (6) through the RS-485 transceiver by the transmitting pin and the receiving pin of the onboard serial communication interface.
  3. 3. The three-phase catalytic oxidation treatment system for printing and dyeing wastewater according to claim 1, wherein the heterogeneous catalytic oxidation main reactor (2) comprises a pressure-bearing reaction tower body, an ozone adding and mixing subsystem, a catalyst bed layer and a safety monitoring and control subsystem, the pressure-bearing reaction tower body is of a vertical cylindrical structure, a water inlet is arranged at the top of the pressure-bearing reaction tower body and is connected with a water outlet of the pulse electrolysis pretreatment unit (1) through a first pipeline, a water outlet is arranged at the bottom of the pressure-bearing reaction tower body and is connected with a water inlet of the gas-liquid separation and ozone recycling unit (3) through a second pipeline, the ozone adding and mixing subsystem comprises an ozone generator and a venturi jet mixer, a gas outlet of the ozone generator is connected to a gas suction interface of the venturi jet mixer through an ozone conveying pipeline, the venturi jet mixer is communicated with a water inlet main pipeline of the pressure-bearing reaction tower body, the catalyst bed layer is filled in the pressure-bearing reaction tower body, the catalyst bed layer comprises a plurality of layers of catalyst modules and inert filler layers which are arranged at intervals in an alternating manner from top to bottom, the catalyst modules comprise spherical composite metal oxide catalysts, the safety monitoring and control subsystem comprises a first probe used for monitoring pH value, a second probe used for monitoring oxidation-reduction potential, a third probe used for detecting conductivity, a temperature sensor used for monitoring temperature, a pressure sensor used for monitoring pressure, a liquid level switch arranged on the pressure-bearing reaction tower body, a flowmeter arranged on the water inlet main pipeline of the pressure-bearing reaction tower body, and the first probe, the second probe, the third probe and the temperature sensor, the pressure sensor is embedded in the side wall of the pressure-bearing reaction tower body at different heights, a cooling water pipe is communicated with a coil in the pressure-bearing reaction tower body, a water flow switch is communicated with the cooling water pipe, a remote control interface and an analog power adjusting interface of the ozone generator are connected to a central intelligent control unit (6), and a normally closed contact of the liquid level switch, a low-flow alarming contact of the flowmeter and a normally closed contact of the water flow switch are connected in series and then connected to a coil loop of a main power contactor of the ozone generator through a control cable.
  4. 4. The three-phase catalytic oxidation treatment system for printing and dyeing wastewater according to claim 1, wherein the gas-liquid separation and ozone recycling unit (3) comprises a gas-liquid separator, a gas compression purification assembly, a recycling control valve group and an ozone concentration monitor, wherein the gas inlet of the gas-liquid separator is connected with the top tail gas outlet of the multi-phase catalytic oxidation main reactor (2) through a third pipeline, the bottom liquid phase outlet of the gas-liquid separator is connected with the treated water body through a fourth pipeline, the top gas phase outlet of the gas-liquid separator is sequentially connected with the gas inlet of the gas compression purification assembly through a fifth pipeline, the gas compression purification assembly sequentially comprises a vortex gas compressor, a freeze dryer and a molecular sieve adsorption tank which are communicated through flanges and sealing pipelines along the gas flow direction, the purified gas outlet of the molecular sieve adsorption tank is connected with the fresh oxygen mixing gas inlet of an ozone generator in the multi-phase catalytic oxidation main reactor (2) through a sixth pipeline, the recycling control valve comprises a pneumatic control valve arranged on the sixth pipeline, the control signal input end of the valve positioner in the pneumatic control valve is connected with the analog quantity output module of the central intelligent control unit (6) through a twisted pair shielding, the analog quantity detector is connected with the analog quantity output module of the analog quantity detector through the intelligent quantity detector, the analog quantity detector is connected with the analog quantity signal input module of the analog quantity analyzer through the analog quantity analog signal input module of the analog quantity analyzer, the start-stop end of the control loop of the vortex type gas compressor is connected to a normally open contact of an intermediate relay driven by a digital quantity output module in a central intelligent control unit (6) through a control cable.
  5. 5. The three-phase catalytic oxidation treatment system according to claim 1, wherein the terminal biotoxicity online early warning unit (4) comprises a biotrophic tank body, an image acquisition subsystem and an auxiliary control subsystem, wherein a water inlet of the biotrophic tank body is connected with a water outlet of an air-liquid separation and ozone recycling unit (3) through a pipeline, the biotrophic tank body is a stepped water flowing tank made of transparent materials, the inside of the biotrophic tank body is divided into at least two mutually communicated observation chambers through a partition plate, an inert matrix is paved at the bottom of each observation chamber for accommodating specific types of indicative aquatic organisms, the image acquisition subsystem comprises industrial cameras, each industrial camera is fixed right above the observation chamber through an adjustable bracket, each industrial camera is connected to an industrial ethernet switch in a central intelligent control unit (6) through a network cable, the auxiliary control subsystem comprises an LED strobe light source and a synchronous trigger, an external trigger input end on the LED strobe light source is arranged above the side of the observation chamber and is connected to an output end of the synchronous trigger through a signal line, and the output end of the synchronous trigger is connected to an output end of the synchronous trigger through the intelligent control unit (6).
  6. 6. The three-phase catalytic oxidation treatment system for printing and dyeing wastewater according to claim 1, wherein the online metal ion monitoring and adsorption enrichment unit (5) comprises a monitoring sampling module, a signal conditioning circuit and an adsorption switching execution module, the monitoring sampling module comprises a detection tank, a water inlet and a water outlet of the detection tank are respectively communicated with a second pipeline between a water outlet of a multi-phase catalytic oxidation main reactor (2) and a water inlet of a gas-liquid separation and ozone recycling unit (3) through a three-way valve, an ion selective electrode and a reference electrode are packaged in the detection tank, a signal output line of the ion selective electrode passes through the detection tank, a signal input interface of the signal conditioning circuit is connected with the output lines of the ion selective electrode and the reference electrode through a shielding cable, the signal conditioning circuit comprises a junction field effect transistor operational amplifier, a precise operational amplifier chip and a microcontroller, an output end of the junction field effect transistor operational amplifier is connected with an input end of the precise operational amplifier, an output end of the precise operational amplifier is connected with the analog-digital converter chip, a peripheral microcontroller is connected with the three-way valve through a serial port, the two-phase operational amplifier is connected with the three-way valve through the three-way valve, the three-way valve is connected with the three-way valve adsorption unit through the three-way valve, the adsorption unit is jointly connected with the three-port adsorption unit through the three-way valve, the adsorption unit, the three-port adsorption unit is connected with the three-phase adsorption unit through one adsorption unit, and three-phase adsorption unit through one pipeline, the air inlet three-way valve and the air outlet three-way valve are double-coil electromagnetic valves, and coils of the double-coil electromagnetic valves are connected to an intermediate relay contact controlled by a digital quantity output module in the central intelligent control unit (6) through control lines.
  7. 7. The three-phase catalytic oxidation treatment system according to claim 1, wherein the central intelligent control unit (6) comprises a main controller, a communication network device and a signal input/output module, the main controller is a programmable logic controller and is connected with the signal input/output module through a back board bus, the communication network device comprises an industrial Ethernet switch, a plurality of network ports of the industrial Ethernet switch are respectively connected to a digital signal processor in the pulse electrolysis pretreatment unit (1), an ozone generator in the multiphase catalytic oxidation main reactor (2), a microcontroller in the online metal ion monitoring and adsorption enrichment unit (5) and an industrial camera in the terminal biotoxicity online early warning unit (4) through Ethernet cables, the signal input/output module comprises an analog quantity input module, an analog quantity output module, a digital quantity input module and a digital quantity output module, wherein a plurality of input channels of the analog quantity input module are respectively connected to a first probe, a second probe, a third probe, a temperature sensor, a pressure sensor and a standard current signal output end of an ozone concentration monitor in a gas-liquid separation and ozone recycling unit (3) in a heterogeneous catalytic oxidation main reactor (2) through shielded twisted pairs, and a plurality of output channels of the analog quantity output module are respectively connected to an analog setting end of a high-frequency pulse power supply in a pulse electrolysis pretreatment unit (1) through shielded twisted pairs, a power regulating end of an ozone generator in the heterogeneous catalytic oxidation main reactor (2), and a valve positioner control end for pneumatic adjustment in the gas-liquid separation and ozone recycling unit (3), wherein a plurality of output channels of the digital quantity output module are respectively connected to a gas inlet three-way valve and a gas outlet three-way valve in the on-line metal ion monitoring and adsorption enrichment unit (5) and coils of a plurality of intermediate relays of the vortex type gas compressor in the gas-liquid separation and ozone recycling unit (3) through control cables.

Description

Printing and dyeing wastewater three-phase catalytic oxidation treatment system Technical Field The invention relates to the technical field of sewage treatment, in particular to a three-phase catalytic oxidation treatment system for printing and dyeing wastewater. Background The three-phase catalytic oxidation treatment of printing and dyeing wastewater is an efficient advanced treatment technology, belongs to the Fenton or similar advanced oxidation technology category, and utilizes strong-oxidability free radicals to thoroughly degrade refractory organic matters such as dye, auxiliary agent and the like remained after biochemical treatment by constructing a gas-liquid-solid three-phase coexisting reaction environment in a specific reactor, so that the power-assisted wastewater can realize up-to-standard emission or recycling. Compared with the traditional homogeneous Fenton method, the three-phase turbulence formed by aeration in the reactor can obviously enhance the contact efficiency of pollutants, oxidants and catalyst active sites, quicken the reaction process, broaden the application range of pH, reduce the medicament consumption and the salt increase of acid regulation and alkali regulation, reduce the sludge yield and lighten the difficulty and the cost of subsequent sludge treatment. In engineering application, the device is often used as a deep treatment unit and is arranged after biochemical treatment, a typical flow comprises pretreatment, biochemical treatment, three-phase catalytic oxidation reaction, neutralization precipitation and other links, and the operation parameters need to be combined with the actual water quality to determine an optimal value through experiments. At present, the technology has moved from research to engineering application, has stable treatment effect, can lead the indexes such as waste water COD to reach the discharge standard, can be coupled with technologies such as membrane separation and the like, constructs a more efficient integrated treatment system, and is suitable for the treatment requirements of different printing and dyeing wastewater. In order to meet zero direct discharge standard, large chemical fiber printing and dyeing enterprises in coastal areas introduce an ozone three-phase catalytic oxidation process to treat high-salt bromine-containing organic amine-containing wastewater, conventional online monitoring is only aimed at macroscopic indexes such as COD, pH and the like, trace amounts of brominated amine-brominated nitromethane and other genetic toxicity byproducts generated by catalysis on the surface of a catalyst cannot be identified, slow leaching of catalyst metal ions caused by complexing agents and instantaneous low pH is difficult to capture in early stage, so that the treatment process is hidden with two major associated fatal problems, firstly, an active site of the catalyst unexpectedly becomes an assembly platform for converting harmless halogen into high-toxicity organic halide, so that effluent is hidden in an up-to-standard appearance, secondly, trace leached metal ions are used for causing out-of-control homogeneous catalytic reaction in a liquid phase, hijacking and consuming a large amount of ozone, operators can further reduce pH to accelerate metal leaching, finally, the system is subjected to triple operation cost of high-level and high-quality biological toxicity of water, high-standard and high-quality chemical oxygen demand, and permanent inactivation of the catalyst are caused under the condition of no effective early warning, so that the whole treatment unit is completely and completely lost in economy and environment is caused. Therefore, a three-phase catalytic oxidation treatment system for printing and dyeing wastewater is provided to solve or alleviate the problems. Disclosure of Invention The invention aims to solve the defects in the prior art, and provides a three-phase catalytic oxidation treatment system for printing and dyeing wastewater. In order to achieve the above purpose, the present invention adopts the following technical scheme: a three-phase catalytic oxidation treatment system for printing and dyeing wastewater comprises The pulse electrolysis pretreatment unit is used for decomposing pollutants through pulse electrolysis oxidation and adjusting current and duty ratio according to the catalyst health degree and the bromide ion concentration; The heterogeneous catalytic oxidation main reactor is used for catalyzing ozone to generate hydroxyl radical oxidation pollutants by using a supported catalyst and dynamically optimizing the ozone addition amount, the pH value and the oxidation-reduction potential according to the oxidation efficiency and the toxicity risk which are evaluated in real time; The gas-liquid separation and ozone recycling unit is used for performing gas-liquid separation on the reaction tail gas and recycling the tail gas containing ozone to the ozone generator after compression