Deterioration monitoring and durability synchronous improving method for flotation tank of seawater desalination plant

Abstract

The invention discloses a method for monitoring degradation and synchronously improving durability of a flotation tank of a seawater desalination plant. The method comprises the following steps: S1, preparing UHPC slurry capable of conducting electricity / heat; s2, the UHPC slurry is poured to the seawater corrosion part of the flotation tank component to serve as a mechano-electric / thermal intelligent sensing layer, and a carbon fiber cloth top electrode and a carbon fiber cloth bottom electrode are pressed into the flotation tank component before the UHPC slurry is solidified; a reference electrode and a titanium mesh electrode which are connected with a reinforcing mesh of the component are embedded in a seawater corrosion part of the component, the carbon fiber cloth top electrode is electrically connected with the titanium mesh electrode, and the carbon fiber cloth bottom electrode is electrically connected with the reference electrode; s3, electrically connecting the negative electrode of a power supply system with the reference electrode and the carbon fiber cloth bottom electrode respectively, and electrically connecting the positive electrode with the titanium mesh electrode and the carbon fiber cloth top electrode respectively to form an electric conduction / heat conduction path; and S4, electric / thermal parameters of the force electric / thermal intelligent sensing layer are tested, so that the stress, strain or displacement borne by the force electric / thermal intelligent sensing layer can be effectively sensed, and the service degradation condition of the flotation tank component is obtained in real time.

Description

Technical Field

[0001] The invention relates to the technical field of seawater desalination, and in particular to a method for synchronously monitoring degradation and improving durability of a flotation pool in a seawater desalination plant. Background Art

[0003] Desalination plants are mostly located near the sea, which is a harsh service environment with high groundwater level, alternating dry and wet conditions, large differences in seawater concentration, and seawater scouring. The flotation tank, which is the primary structural component of the desalination plant, not only has a variety of tank shapes, but also has many filter plates, weir plates, embedded parts, embedded casings, reserved water holes and other components. The large amount of corrosive ions (chloride ions, sulfate ions, etc.) contained in the underground seawater and soil will inevitably invade the interior of these reinforced concrete components, causing the performance and durability of the primary structural component, the flotation tank, to inevitably deteriorate, which in turn affects the overall service effect of the desalination plant.

[0004] However, there is currently no effective monitoring of the possible performance degradation of the flotation tank, which brings inconvenience to understanding the service degradation of the desalination plant. Summary of the invention

[0005] In view of this, the present invention provides a method for monitoring the degradation and simultaneously improving the durability of a flotation tank in a seawater desalination plant, which can effectively monitor the service degradation of flotation tank components and facilitate understanding of the service degradation of the seawater desalination plant.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A method for monitoring degradation and improving durability of a flotation tank in a seawater desalination plant comprises the following steps:

[0008] S1. Preparing UHPC slurry capable of conducting electricity and heat;

[0009] S2. Pour the UHPC slurry onto the seawater corrosion part of the flotation tank component to serve as a mechanical / electrical / thermal intelligent sensing layer, and press the carbon fiber cloth top electrode and the carbon fiber cloth bottom electrode into the component before the UHPC slurry solidifies; wherein the seawater corrosion part of the component is in contact with the seawater, and a reference electrode and a titanium mesh electrode connected to the steel mesh are buried, and the carbon fiber cloth top electrode is electrically connected to the titanium mesh electrode of the steel mesh, and the carbon fiber cloth bottom electrode is electrically connected to the reference electrode of the steel mesh;

[0010] S3, electrically connecting the negative electrode of the power supply system to the reference electrode and the carbon fiber cloth bottom electrode, and electrically connecting the positive electrode to the titanium mesh electrode and the carbon fiber cloth top electrode, respectively, to form an electrical / thermal conduction path;

[0011] S4. Test the electrical / thermal parameters of the electromechanical / thermal smart sensing layer.

[0012] Preferably, in step S1, the preparation of the electrically / thermally conductive UHPC slurry comprises:

[0013] The most compact effect of UHPC slurry is determined according to the closest packing theory, and the raw material ratio of UHPC is determined accordingly. Cement, steel fiber, fly ash, silica fume, microspheres, fine aggregate, admixtures and water are stirred and mixed evenly according to the proportion to obtain UHPC slurry that can conduct electricity and heat.

[0014] Preferably, the mass ratio of cement, steel fiber, fly ash, silica fume, microspheres, fine aggregate, admixture and water is 1: 0.005-0.02: 0.05-0.10: 0.01-0.10: 0.05-0.10: 0.95-1.5: 0.005-0.015: 0.18-0.22.

[0015] Preferably, in step S2, the step of acting as a mechanoelectric / thermal intelligent sensing layer comprises:

[0016] Serves as a durability reinforcement layer, cathodic protection layer, and electromechanical / thermal smart sensing layer.

[0017] Preferably, after step S2, the method further includes:

[0018] The water permeability resistance, chloride ion corrosion resistance and frost resistance of the durability reinforcement layer were tested using a vacuum water saturation instrument, a chloride ion rapid penetration instrument and a rapid freeze-thaw cycle machine.

[0019] Preferably, after step S2, the method further includes:

[0020] The negative electrode of the power supply system is electrically connected to the reference electrode of the steel mesh and the bottom electrode of the carbon fiber cloth, and the positive electrode is electrically connected to the titanium mesh electrode and the top electrode of the carbon fiber cloth, so as to form a steel mesh cathodic protection circuit.

[0021] Preferably, after forming the steel mesh cathodic protection loop, the method further comprises:

[0022] The electrochemical method is used to determine the corrosion immunity of the steel mesh in the seawater corrosion area of ​​the component under common seawater corrosion media and concentrations.

[0023] Preferably, in step S4, the testing of the electrical / thermal parameters of the electromechanical / thermal intelligent sensing layer includes:

[0024] The resistivity, impedance, capacitance and thermoelectric coefficient of the electromechanical / thermoelectric smart layer are tested respectively using a signal acquisition instrument, an LCR bridge or a thermoelectric coefficient acquisition instrument.

[0025] Preferably, after using a signal acquisition instrument, an LCR bridge or a thermoelectric coefficient acquisition instrument to test the resistivity, impedance, capacitance and thermoelectric coefficient of the electromechanical / thermoelectric smart layer, the method further includes:

[0026] The electrical / thermal parameters are extracted using signal differential temperature compensation and band-pass filtering modulation post-processing techniques.

[0027] It can be seen from the above technical scheme that in the method for monitoring degradation and improving durability of the flotation tank of a seawater desalination plant provided by the present invention, firstly, a UHPC slurry capable of conducting electricity and heat is prepared, and then the UHPC slurry is poured onto the seawater corrosion part of the flotation tank component to act as or be used as a mechanoelectric / thermal intelligent sensing layer, and then the negative electrode of the power supply system is electrically connected to the reference electrode and the carbon fiber cloth bottom electrode, and the positive electrode is electrically connected to the titanium mesh electrode and the carbon fiber cloth top electrode, respectively, to form a conductive / thermal conductive path, thereby constructing a flotation tank degradation monitoring system based on the UHPC mechanoelectric / thermoelectric intelligent sensing layer, and then testing the electrical / thermal parameters of the mechanoelectric / thermal intelligent sensing layer, so as to effectively perceive the stress, strain or displacement of the mechanoelectric / thermal intelligent sensing layer, so as to obtain the service degradation of the flotation tank components in real time, that is, to effectively monitor the service degradation of the flotation tank components, so as to understand the service degradation of the seawater desalination plant. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 A flow chart of a method for monitoring degradation and simultaneously improving durability of a flotation tank in a seawater desalination plant provided by an embodiment of the present invention;

[0030] Figure 2 A technical framework diagram for monitoring tank degradation and improving durability of a flotation tank in a seawater desalination plant based on a UHPC protective layer according to an embodiment of the present invention.

[0031] Among them, 1 is a UHPC thin layer (UHPC protective layer), 2 is a power supply, 3 is a cell body (cell body of a flotation cell), 4 is a carbon fiber cloth top electrode, 5 is a reference electrode, 6 is a steel mesh, 7 is a titanium mesh anode (titanium mesh electrode), and 8 is a cathodic protection / deterioration monitoring test system. DETAILED DESCRIPTION

[0032] The present invention uses the UHPC protective layer as the durability reinforcement layer, cathodic protection layer and electromechanical / thermal intelligent sensing layer of each component of the flotation tank of the seawater desalination plant, and simultaneously constructs a flotation tank durability improvement system based on the UHPC durability reinforcement layer, a flotation tank cathodic protection steel bar anti-corrosion system based on the UHPC cathodic protection layer, and a flotation tank degradation monitoring system based on the UHPC electromechanical / thermal intelligent sensing layer. The titanium mesh electrode and the carbon fiber cloth top electrode are respectively used as the positive and negative electrodes of the degradation monitoring system, thereby effectively ensuring the long-term safe operation and service life of the urban lifeline project of the seawater desalination plant under harsh environment.

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The method for monitoring degradation and improving durability of a flotation tank in a desalination plant provided by the embodiment of the present invention is as follows: Figure 1 As shown, the following steps are included:

[0035] S1. Preparing UHPC slurry capable of conducting electricity and heat;

[0036] S2, pouring UHPC slurry onto the seawater corrosion part of the flotation tank component to serve as a mechanical / electrical / thermal intelligent sensing layer, and pressing the carbon fiber cloth top electrode 4 and the carbon fiber cloth bottom electrode into the UHPC slurry before solidification; wherein, Figure 2 As shown, the seawater corrosion part of the component is in contact with seawater, and a reference electrode 5 and a titanium mesh electrode connected to the steel mesh 6 are buried, and the carbon fiber cloth top electrode 4 is electrically connected to the titanium mesh electrode of the steel mesh 6, and the carbon fiber cloth bottom electrode is electrically connected to the reference electrode 5 of the steel mesh 6;

[0037] S3, the negative electrode of the power supply system is electrically connected to the reference electrode 5 and the carbon fiber cloth bottom electrode, and the positive electrode is electrically connected to the titanium mesh electrode and the carbon fiber cloth top electrode 4, respectively, to form an electrical / thermal conduction path;

[0038] S4. Test the electrical / thermal parameters of the electromechanical / thermal smart sensing layer.

[0039] It should be noted that in step S1, the UHPC slurry, i.e., the ultra-high performance concrete slurry, utilizes the electrical / thermal conduction path of the steel fibers in the UHPC slurry, and then under the applied stress / strain, its electrical and thermal parameters will change due to the change of electrical / thermal carrier tunneling and the number of physical overlaps, thereby realizing the electromechanical / thermal sensing performance. When the UHPC slurry acts as an intelligent sensing layer, it has the ability to effectively sense the stress / strain and crack damage it is subjected to;

[0040] In step S2, the component of the flotation tank of the seawater desalination plant can be one of the filter plate, the weir plate, the embedded parts, the embedded casing, and the reserved water hole. That is, the UHPC slurry can be poured on the seawater corrosion part of the filter plate, the weir plate, the embedded parts, the embedded casing, and the reserved water hole of the flotation tank. The seawater corrosion part of the component is in contact with the seawater, and the reference electrode 5 and the titanium mesh electrode are embedded before pouring the UHPC slurry. The reference electrode 5 and the titanium mesh electrode are electrically connected to the steel mesh 6 at the seawater corrosion part of the component. The titanium mesh electrode and the carbon fiber cloth electrode are used as the negative electrode and the positive electrode of the steel mesh 6 at the seawater corrosion part of the component respectively; the carbon fiber cloth top electrode 4 and the carbon fiber cloth bottom electrode are pressed into the UHPC slurry before solidification; wherein, the carbon fiber cloth top electrode 4 is electrically connected to the titanium mesh electrode of the steel mesh 6, and the carbon fiber cloth bottom electrode is electrically connected to the reference electrode 5 of the steel mesh 6, the carbon fiber cloth top electrode 4 is equivalent to the positive electrode, and can be distributed on the top of the mechanical and electrical / thermal intelligent sensing layer, and the carbon fiber cloth bottom electrode is equivalent to the negative electrode, and can be distributed on the bottom of the mechanical and electrical / thermal intelligent sensing layer;

[0041] In step S3, the negative electrode of the power supply system is electrically connected to the reference electrode 5 and the carbon fiber cloth bottom electrode respectively through the cable, and the positive electrode is electrically connected to the titanium mesh electrode and the carbon fiber cloth top electrode 4 respectively to form an electrically conductive / thermal conductive path, thereby constructing a flotation tank degradation monitoring system based on the UHPC electromechanical / thermoelectric intelligent sensing layer; wherein the power supply system may include: a constant voltage rectifier, a constant potentiostat or a photovoltaic cell; in addition, the titanium mesh electrode (i.e., the titanium mesh anode 7) and the carbon fiber cloth top electrode 4 are respectively used as the positive electrode and the negative electrode of the flotation tank degradation monitoring system;

[0042] In step S4, the electrical / thermal parameters of the electromechanical / thermal intelligent sensing layer are tested to effectively sense the stress, strain or displacement of the electromechanical / thermal intelligent sensing layer, so as to obtain the service degradation of the flotation tank components in real time, that is, to effectively monitor the service degradation of the flotation tank components; wherein, the electrical / thermal parameters such as resistivity, impedance, capacitance, and thermoelectric coefficient of the UHPC electromechanical / thermal intelligent sensing layer can be tested by a signal acquisition instrument, an LCR bridge or a thermoelectric coefficient acquisition instrument.

[0043] Of course, the flotation tank degradation monitoring system based on the UHPC electromechanical / thermoelectric intelligent sensing layer can be built by technicians familiar with the art, mainly including power supply, positive and negative electrodes, and UHPC electromechanical / thermoelectric intelligent sensing layer. The corresponding system degradation monitoring and evaluation can also adopt technical methods familiar to the art;

[0044] In addition, the method provided in this scheme for monitoring the degradation of flotation tank components in a seawater desalination plant can also be applied to places such as the flotation tank workshop, ultrafiltration water inlet pump room, mineralization filter tank, product water pool, water delivery pump room and brine pool of a seawater desalination plant.

[0045] That is to say, this scheme actually provides a method for monitoring the degradation of flotation tank components in a seawater desalination plant. First, a UHPC slurry capable of conducting electricity and heat is prepared. Secondly, the UHPC slurry is poured onto the seawater corrosion part of the flotation tank components to act as or be used as a mechanoelectric / thermal intelligent sensing layer. Then, the negative electrode of the power supply system is electrically connected to the reference electrode 5 and the carbon fiber cloth bottom electrode, respectively, and the positive electrode is electrically connected to the titanium mesh electrode and the carbon fiber cloth top electrode 4, respectively, to form an electrically conductive / thermally conductive path, thereby constructing a flotation tank degradation monitoring system based on the UHPC mechanoelectric / thermoelectric intelligent sensing layer. Then, the electrical / thermal parameters of the mechanoelectric / thermal intelligent sensing layer are tested, thereby facilitating the effective perception of the stress, strain or displacement of the mechanoelectric / thermal intelligent sensing layer, so as to obtain the service degradation of the flotation tank components in real time, that is, to effectively monitor the service degradation of the flotation tank components, so as to understand the service degradation of the seawater desalination plant.

[0046] In step S1, the preparation of the electrically / thermally conductive UHPC slurry comprises:

[0047] The most compact effect of UHPC raw materials is determined according to the closest packing theory, and the UHPC raw material ratio is determined accordingly. Cement, steel fiber, fly ash, silica fume, microspheres, fine aggregate, admixtures and water are stirred and mixed evenly according to the ratio to obtain UHPC slurry that can conduct electricity and heat.

[0048] It should be noted that in the UHPC special mixing equipment, the most compact effect of each micro-powder of UHPC is determined according to the most compact packing theory, and then the water-cement ratio and sand ratio of the UHPC raw materials are determined, that is, the UHPC raw material ratio is determined, and then the cement, steel fiber, fly ash, silica fume, micro beads, fine aggregate, admixture and water are mixed evenly according to the ratio to obtain UHPC slurry that can conduct electricity / heat. In this way, the obtained UHPC slurry has a better compact effect; in addition, the raw materials of UHPC include the above-mentioned cement, steel fiber, fly ash, silica fume, micro beads, fine aggregate, admixture and water; among them, steel fiber can conduct electricity and heat. Of course, the preparation of UHPC slurry can adopt existing process technology.

[0049] Specifically, the mass ratio of cement, steel fiber, fly ash, silica fume, microspheres, fine aggregate, admixture and water is 1: 0.005-0.02: 0.05-0.10: 0.01-0.10: 0.05-0.10: 0.95-1.5: 0.005-0.015: 0.18-0.22.

[0050] That is to say, the ratio of UHPC raw materials is: cement: steel fiber: fly ash: silica fume: microspheres: fine aggregate: admixture: water, and the mass ratio is 1: (0.005-0.02): (0.05-0.10): (0.01-0.10): (0.05-0.10): (0.95-1.5): (0.005-0.015): (0.18-0.22); among them, cement, steel fiber, fly ash, silica fume, microspheres, fine aggregate, admixture and water are stirred and mixed evenly according to different mass ratios (ratios), so that UHPC slurry with different strength grades and different uses can be obtained. For example, to obtain C100 grade UHPC slurry, the mass ratio of cement, steel fiber, fly ash, silica fume, microspheres, fine aggregate, admixture and water in its raw materials can be 1:0.01:0.1:0.05:0.01:1.2:0.015:0.2.

[0051] In step S2, the step of acting as a mechanoelectric / thermal intelligent sensing layer includes:

[0052] Serves as a durability reinforcement layer, cathodic protection layer, and electromechanical / thermal smart sensing layer.

[0053] It should be noted that the UHPC slurry poured onto the seawater corrosion parts of the flotation tank components is the UHPC protective layer (concrete protective layer), which can serve as a durability reinforcement layer and a cathodic protection layer on the seawater corrosion parts of the flotation tank components, and can also serve as a mechanoelectric / thermal intelligent sensing layer; wherein, the UHPC protective layer has high surface mechanical toughness, good impermeability and durability, and good intelligent sensing layer, and can be well used as the durability reinforcement layer, cathodic protection layer and mechanoelectric / thermal intelligent sensing layer of the filter plate, weir plate, embedded parts, embedded casing and / or reserved water passage opening of the flotation tank, which can help to realize degradation monitoring and improve durability of the seawater corrosion parts of the flotation tank components, and thus can simultaneously realize its degradation monitoring and durability improvement effects. In addition, UHPC slurry can be buried in the pre-buried casing and reserved water holes of the flotation tank of the seawater desalination plant to serve as a durability reinforcement layer, and of course it can also serve as a cathode protection layer and a mechanoelectric / thermal intelligent sensing layer; UHPC slurry can be poured onto the filter plate and weir plate of the flotation tank, and simultaneously serve as a cathode protection layer, a mechanoelectric / thermal intelligent sensing layer, and of course it can also serve as a durability reinforcement layer, and the carbon fiber cloth counter electrode (i.e., the carbon fiber cloth top electrode and the carbon fiber cloth bottom electrode) can be pressed into it before hardening.

[0054] That is to say, this solution prepares a UHPC slurry that is electrically / thermally conductive and applies it to the components of the flotation tank of the desalination plant, and simultaneously uses it as a durability reinforcement layer (concrete protective layer), a cathodic protection layer, and a mechanoelectric / thermal intelligent sensing layer to achieve degradation monitoring and durability improvement of the components of the flotation tank of the desalination plant. Of course, this also helps to simultaneously build a flotation tank durability improvement system based on the UHPC durability reinforcement layer, a flotation tank cathodic protection steel bar anti-corrosion system based on the UHPC cathodic protection layer, and a flotation tank degradation monitoring system based on the UHPC mechanoelectric / thermoelectric intelligent layer, thereby achieving a three-in-one degradation monitoring and durability improvement effect.

[0055] After step S2, the method further includes:

[0056] The water permeability resistance, chloride ion erosion resistance and frost resistance of the durability reinforcement layer were tested using a vacuum water saturation instrument, a chloride ion rapid permeability instrument and a rapid freeze-thaw cycler, respectively. In this way, a flotation tank durability improvement system based on the UHPC durability reinforcement layer was constructed. That is, the water permeability resistance, chloride ion erosion resistance and frost resistance of the UHPC durability reinforcement layer were evaluated using a vacuum water saturation instrument, a chloride ion rapid permeability instrument and a rapid freeze-thaw cycler, respectively. Of course, the durability reinforcement layer can effectively improve the overall durability of the components (such as filter plates and weir plates) covered by the flotation tank.

[0057] After step S2, the method further includes:

[0058] The negative electrode of the power supply system is electrically connected to the reference electrode 5 of the steel mesh and the bottom electrode of the carbon fiber cloth, and the positive electrode is electrically connected to the titanium mesh electrode and the top electrode 4 of the carbon fiber cloth, to form a steel mesh cathodic protection circuit.

[0059] It should be noted that the negative electrode of the power supply system is electrically connected to the reference electrode 5 of the steel mesh (that is, the cathode of the steel mesh) and the bottom electrode of the carbon fiber cloth through the cable, and the positive electrode is electrically connected to the titanium mesh electrode of the steel mesh (which can be a titanium mesh anode plate) and the top electrode 4 of the carbon fiber cloth, respectively, to form a steel mesh cathodic protection circuit, adjust the potential and current value of the power supply system, and build an impressed current cathodic protection steel anti-corrosion system for flotation tank components (such as filter plates and weir plates). In this way, a flotation tank cathodic protection steel anti-corrosion system based on the UHPC cathodic protection layer is constructed, so that the corrosive ions of the steel mesh can be conducted away through the circuit or passage, which can have an anti-corrosion effect on the steel bars of the flotation tank components; wherein, the power supply system includes components such as a constant voltage rectifier, a constant potentiostat, and a photovoltaic cell.

[0060] In addition, the cathodic protection steel bar anti-corrosion system of the flotation tank based on the UHPC cathodic protection layer can be constructed by technical personnel familiar with the art, and mainly includes a power supply system, a reference electrode, a carbon fiber cloth top electrode 4, a UHPC cathodic protection layer, and a titanium mesh anode plate. The steel bar anti-corrosion performance test and evaluation of the corresponding system can also adopt technical methods familiar to the art; of course, the power supply system, titanium mesh electrode and carbon fiber cloth top electrode 4 in the flotation tank cathodic protection steel bar anti-corrosion system actually serve as the power supply system, positive electrode and negative electrode of the degradation monitoring system respectively.

[0061] After the steel mesh cathodic protection loop is formed, the method further comprises:

[0062] The electrochemical method is used to determine the corrosion immunity of the steel mesh in the seawater corrosion area of ​​the component under common seawater corrosion media and concentrations.

[0063] It should be noted that, in combination with the electrochemical workstation platform, the corrosion immunity of the steel mesh at the seawater corrosion site of the flotation tank components in common seawater corrosion media and concentrations (3.5% NaCl or 5.0% Na2SO4) is determined by electrochemical methods (such as half-cell potential method, polarization curve method or AC impedance method) (the corrosion potential, polarization resistance, electrochemical impedance, etc. of the steel mesh can be determined), so as to evaluate the immunity of the steel bars at the seawater corrosion site of the flotation tank components to seawater corrosion.

[0064] In other words, this solution uses the UHPC protective layer as the durability reinforcement layer, cathodic protection layer and electromechanical / thermal intelligent sensing layer of each component of the flotation tank of the seawater desalination plant, and simultaneously constructs a flotation tank durability improvement system based on the UHPC durability reinforcement layer, a flotation tank cathodic protection steel bar anti-corrosion system based on the UHPC cathodic protection layer, and a flotation tank degradation monitoring system based on the UHPC electromechanical / thermoelectric intelligent layer. The titanium mesh electrode and the carbon fiber cloth top electrode are used as the positive and negative electrodes of the degradation monitoring system respectively, effectively ensuring the long-term safe operation and service life of the urban lifeline project of the seawater desalination plant under harsh environment.

[0065] In step S4, the testing of the electrical / thermal parameters of the electromechanical / thermal intelligent sensing layer includes:

[0066] Use a signal acquisition instrument, LCR bridge or thermoelectric coefficient acquisition instrument to test the resistivity, impedance, capacitance and thermoelectric coefficient of the electromechanical / thermoelectric smart layer.

[0067] It should be noted that the resistivity, impedance, capacitance and thermoelectric coefficient of the UHPC mechanoelectric / thermoelectric smart layer are tested by a signal acquisition instrument, an LCR bridge or a thermoelectric coefficient acquisition instrument. That is, the piezoresistive sensing performance, electrical conductivity and thermoelectric coefficient of the UHPC mechanoelectric / thermoelectric smart layer are respectively tested by a signal acquisition instrument, an LCR bridge or a thermoelectric coefficient acquisition instrument, so as to effectively sense the stress, strain or displacement of the UHPC mechanoelectric / thermoelectric smart layer, so as to obtain the service degradation of the flotation tank components in real time.

[0068] After using a signal acquisition instrument, an LCR bridge or a thermoelectric coefficient acquisition instrument to test the resistivity, impedance, capacitance and thermoelectric coefficient of the electromechanical / thermoelectric smart layer, the method further includes:

[0069] The electrical / thermal parameters are extracted by using signal differential temperature compensation and band-frequency filtering modulation post-processing technology. That is, the electrical / thermal parameters are accurately extracted by using signal differential temperature compensation and band-frequency filtering modulation post-processing technology, which is equivalent to removing impurities from the electrical / thermal parameters and ensuring the accuracy of the electrical / thermal parameters.

[0070] That is to say, a method for monitoring the degradation and improving the durability of a flotation tank in a desalination plant based on a UHPC protective layer may specifically include the following steps:

[0071] S1. Preparation of UHPC protective layer:

[0072] S11. In a special mixing device for UHPC, the most compact effect of each micro-powder of UHPC is determined according to the most compact packing theory, and then the typical water-cement ratio and sand ratio are determined. Cement, steel fiber, fly ash, silica fume, microspheres, fine aggregate, admixtures and water are mixed evenly according to the proportions of UHPC of different grades and uses (the mass ratio of cement: steel fiber: fly ash: silica fume: microspheres: fine aggregate: admixture: water is 1: (0.005-0.02): (0.05-0.10): (0.01-0.10): (0.05-0.10): (0.95-1.5): (0.005-0.015): (0.18-0.22)) to obtain UHPC slurry of different strength grades and uses;

[0073] S12, burying the UHPC slurry described in S11 into the pre-buried casing and reserved water hole of the flotation tank of the seawater desalination plant to serve as a durability reinforcement layer; pouring the UHPC slurry described in S11 onto the filter plate and weir plate of the flotation tank, simultaneously serving as a cathode protection layer and a mechanical / electrical / thermal intelligent sensing layer, and pressing the carbon fiber cloth top electrode and the carbon fiber cloth bottom electrode into the filter plate and weir plate of the flotation tank before hardening; wherein, the reference electrode and the anode plate connected to the steel mesh are embedded in the filter plate and the weir plate of the flotation tank;

[0074] S2. Construction of a flotation tank durability improvement system based on the UHPC durability reinforcement layer: Use a vacuum water saturation instrument, a chloride ion rapid permeability instrument, and a rapid freeze-thaw cycler to evaluate the water permeability, chloride ion erosion resistance, and frost resistance of the UHPC durability reinforcement layer, and effectively improve the overall durability of the filter plate and weir plate components of the covered flotation tank;

[0075] S3. Construction of cathodic protection steel bar anti-corrosion system for flotation tank based on UHPC cathodic protection layer: connect the power supply system such as constant voltage rectifier, constant potentiostat or photovoltaic cell to the reference electrode of steel mesh and the bottom electrode of carbon fiber cloth through cables, connect the positive electrode of the above power supply system to the titanium mesh electrode and the top electrode of carbon fiber cloth through cables, form a steel mesh cathodic protection circuit, adjust the potential and current value of the power supply, and build an impressed current cathodic protection steel bar anti-corrosion system for flotation tank filter plate and weir plate components; combine with electrochemical workstation platform, and determine the corrosion immunity of steel mesh under common seawater corrosion medium and concentration (3.5% NaCl or 5.0% Na2SO4) of flotation tank by electrochemical method (half-cell potential method, polarization curve method or AC impedance method);

[0076] S4. Construction of a flotation tank degradation monitoring system based on the UHPC electromechanical / thermoelectric smart layer: The negative electrode of a power system such as a constant voltage rectifier, a constant potentiostat or a photovoltaic cell is electrically connected to a reference electrode and a carbon fiber cloth bottom electrode through a wire, and the positive electrode of the above power system is electrically connected to a titanium mesh electrode and a carbon fiber cloth top electrode through a wire to form a conductive / thermal conductive path. The resistivity, impedance, capacitance, thermoelectric coefficient and other electrical / thermal parameters of the UHPC electromechanical / thermoelectric smart layer are tested in combination with a signal acquisition instrument, an LCR bridge or a thermoelectric coefficient acquisition instrument to effectively sense the stress, strain or displacement (stress / strain sensing sensitivity, signal stability, hysteresis, etc.) to obtain the service degradation of the flotation tank components in real time, and the signal differential temperature compensation and band-frequency filtering modulation post-processing technology are used to accurately extract electrical and thermal signals.

[0077] Among them, in step S11, in the UHPC special mixing equipment, the most compact effect of each micro- and fine powder of UHPC is first determined according to the most compact packing theory, and then the typical water-cement ratio and sand ratio are determined, and cement, steel fiber, fly ash, silica fume, micro beads, fine aggregate, admixture, and water are mixed according to the proportions of UHPC of different grades and different uses by a special mixing equipment well known to those skilled in the art. The most compact effect of each micro- and fine powder of UHPC is determined according to the well-known most compact packing theory, and the existing mixing technology scheme is used for mixing, and UHPC slurries of different grades and different uses are prepared according to different proportions;

[0078] Among them, in step S12, the embedded casing, embedded parts, and reserved water holes of the flotation tank of the seawater desalination plant can be reserved or embedded by those skilled in the art; the filter plates and weir plates of the flotation tank can be designed, constructed, and built by those skilled in the art. The types, specifications, and sizes of the reference electrode (as the steel mesh cathode), anode plate, and carbon fiber cloth top electrode used for connecting the steel mesh of the UHPC cathode protection layer can be designed and embedded by those skilled in the art; when the UHPC protective layer slurry is poured or infused onto the surface or joints of each component of the flotation tank, the surface of the corresponding component or joint can be roughened and roughened in advance using techniques well known in the art;

[0079] Among them, in step S3, the cathodic protection steel bar anti-corrosion system of the flotation tank based on the UHPC cathodic protection layer can be constructed by technicians familiar with the art, mainly including a power supply system, a reference electrode, a carbon fiber cloth counter electrode, a UHPC cathodic protection layer, and a titanium mesh anode plate. The corresponding system steel bar anti-corrosion performance test and evaluation can also adopt technical methods familiar to the art;

[0080] Among them, in step S4, the flotation tank degradation monitoring system based on the UHPC power / thermoelectric smart layer can be built by technicians familiar with the art, mainly including power supply, positive and negative electrodes, and UHPC power / thermoelectric smart layer. The corresponding system degradation monitoring and evaluation can also adopt technical methods familiar to the art;

[0081] In addition, the method for monitoring the degradation and improving the durability of the flotation tank in a desalination plant based on a UHPC protective layer provided by the present invention can also be applied to the flotation tank workshop, ultrafiltration water inlet pump room, mineralization filter tank, product water tank, water supply pump room and brine tank of the desalination plant.

[0082] The present invention is further described below in conjunction with specific embodiments:

[0083] Example 1

[0084] The method for monitoring the degradation of the flotation tank of a seawater desalination plant based on a UHPC protective layer and improving its durability simultaneously in this embodiment has the following specific steps:

[0085] Preparation of S1 and C100 grade UHPC slurry:

[0086] S11. First, determine the most compact effect of each micro-powder of UHPC according to the most compact packing theory, and then determine that the water-solid ratio and the ratio of mineral admixture to cement are 75:25 and 35:65 respectively. Then, in a DMPH-100 type UHPC special planetary mixer, stir and mix silicate cement, steel fiber, fly ash, silica fume, microspheres, fine aggregate, admixtures, and water according to the proportion of C100 grade UHPC (P.I52.5 cement: 6mm long copper-plated steel fiber: S1 grade fly ash: 96 grade silica fume: microspheres: graded quartz sand: PCA-I type polycarboxylic acid high-efficiency water reducing agent: tap water in a mass ratio of 1:0.01:0.1:0.05:0.01:1.2:0.015:0.2) to obtain C100 grade UHPC slurry;

[0087] S12, roughening the surface of the flotation tank filter with a steel brush, welding a conductor on the steel mesh of the filter, and placing a titanium mesh anode plate with a mesh density of 0.4m×0.4m and a specification of 1.2m×1.2m×3mm; then pouring the C100-grade UHPC slurry described in S11 onto the upper surface of the filter, and embedding a carbon fiber cloth top electrode with a specification of 0.6m×0.6m×2mm before the initial setting of the UHPC slurry, to obtain a UHPC protective layer with an overall thickness of 30mm, and also embedding a carbon fiber cloth bottom electrode;

[0088] S2. Construction of the durability improvement system of the flotation tank based on the UHPC durability reinforcement layer: The single-sided water absorption rate, RCM coefficient, and dynamic elastic modulus loss rate after 200 freeze-thaw cycles of the UHPC protective layer were measured using a vacuum water saturation instrument, a chloride ion rapid permeameter, and a rapid freeze-thaw cycler, and the results were 0.5%, 1.37×10-13m2 / s, and 9.5%, respectively. It is obvious that the UHPC protective layer can serve as a UHPC durability reinforcement layer and effectively improve the overall durability of the filter plate and weir plate components of the covered flotation tank;

[0089] S3. The cathodic protection steel bar anti-corrosion system of the flotation tank based on the UHPC cathodic protection layer is constructed: the negative electrode of the 1V constant voltage rectifier power supply is electrically connected to the reference electrode of the steel mesh and the bottom electrode of the carbon fiber cloth through a cable, and the positive electrode of the 1V constant voltage rectifier power supply is electrically connected to the titanium mesh electrode (titanium mesh anode plate) and the carbon fiber cloth top electrode through a cable to form a steel mesh cathodic protection circuit, and an impressed current cathodic protection steel bar anti-corrosion system of the flotation tank filter is constructed. The corrosion potential of the steel mesh under the common seawater corrosion medium and concentration (3.5% NaCl) of the flotation tank is measured by a CS2350H type dual constant potentiostat. The corrosion potential is -126mV, the corrosion current density is 1.58×10-2μA / cm2, and the charge transfer resistance is 29.26kΩ·cm2, which is much lower than the system without cathodic protection. The anti-corrosion effect of the steel mesh in the flotation tank based on the UHPC cathodic protection layer is good;

[0090] S4. The flotation tank degradation monitoring system based on the UHPC electromechanical / thermoelectric intelligent layer is constructed as follows: the negative electrode of the 1V constant voltage rectifier power supply is electrically connected to the steel mesh cathode and the carbon fiber cloth bottom electrode through a cable, and the positive electrode of the 1V constant voltage rectifier power supply is electrically connected to the titanium mesh electrode (titanium mesh anode plate) and the carbon fiber cloth top electrode through a cable to form a conductive / thermal conductive path, thereby building a flotation tank filter degradation monitoring system. The stress sensing sensitivity, strain sensing sensitivity and signal stability of the UHPC protective layer under a stress of 0-15MPa are measured by a dynamic signal acquisition instrument with frequency filtering modulation, which are -5.6% / MPa, 214ppm / με and 1.78% respectively. Obviously, based on the UHPC electromechanical / thermoelectric intelligent layer, the service degradation of the flotation tank filter can be well obtained, and the degradation monitoring effect is good.

[0091] Example 2

[0092] The method for monitoring degradation of a flotation tank in a seawater desalination plant based on a UHPC protective layer and simultaneously improving durability of the present embodiment is substantially the same as that of Embodiment 1, except that a C80 grade UHPC protective layer is selected.

[0093] Example 3

[0094] The method for monitoring tank degradation and simultaneously improving durability of a flotation tank in a seawater desalination plant based on a UHPC protective layer in this embodiment is basically the same as that in Example 1, except that the UHPC protective layer is applied to the weir plate of the flotation tank.

[0095] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0096] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for monitoring the degradation of a flotation tank in a seawater desalination plant and improving its durability simultaneously, characterized in that: The steps include: S1. Preparing UHPC slurry capable of conducting electricity and heat; S2. Pour the UHPC slurry onto the seawater corrosion part of the flotation tank component to serve as a mechanical / electrical / thermal intelligent sensing layer, and press the carbon fiber cloth top electrode and the carbon fiber cloth bottom electrode into the component before the UHPC slurry solidifies; wherein the seawater corrosion part of the component is in contact with the seawater, and a reference electrode and a titanium mesh electrode connected to the steel mesh are buried, and the carbon fiber cloth top electrode is electrically connected to the titanium mesh electrode of the steel mesh, and the carbon fiber cloth bottom electrode is electrically connected to the reference electrode of the steel mesh; S3, electrically connecting the negative electrode of the power supply system to the reference electrode and the carbon fiber cloth bottom electrode, and electrically connecting the positive electrode to the titanium mesh electrode and the carbon fiber cloth top electrode, respectively, to form an electrical / thermal conduction path; S4. Test the electrical / thermal parameters of the electromechanical / thermal smart sensing layer.

2. The method for monitoring degradation and improving durability of a flotation tank in a seawater desalination plant according to claim 1, characterized in that: In step S1, the preparation of the electrically / thermally conductive UHPC slurry comprises: The most compact effect of UHPC slurry is determined according to the closest packing theory, and the raw material ratio of UHPC is determined accordingly. Cement, steel fiber, fly ash, silica fume, microspheres, fine aggregate, admixtures and water are stirred and mixed evenly according to the proportion to obtain UHPC slurry that can conduct electricity and heat.

3. The method for monitoring degradation and improving durability of a flotation tank in a seawater desalination plant according to claim 2, characterized in that: The mass ratio of cement, steel fiber, fly ash, silica fume, microspheres, fine aggregate, admixture and water is 1: 0.005~0.02: 0.05~0.10: 0.01~0.10: 0.05~0.10: 0.95~1.5: 0.005~0.015: 0.18~0.

22.

4. The method for monitoring degradation and improving durability of a flotation tank in a seawater desalination plant according to claim 1, characterized in that: In step S2, the step of acting as a mechanoelectric / thermal intelligent sensing layer includes: Serves as a durability reinforcement layer, cathodic protection layer, and electromechanical / thermal smart sensing layer.

5. The method for monitoring degradation and improving durability of a flotation tank in a seawater desalination plant according to claim 4, characterized in that: After step S2, the method further includes: The water permeability resistance, chloride ion corrosion resistance and frost resistance of the durability reinforcement layer were tested using a vacuum water saturation instrument, a chloride ion rapid penetration instrument and a rapid freeze-thaw cycle machine.

6. The method for monitoring degradation and improving durability of a flotation tank in a seawater desalination plant according to claim 4, characterized in that: After step S2, the method further includes: The negative electrode of the power supply system is electrically connected to the reference electrode of the steel mesh and the bottom electrode of the carbon fiber cloth, and the positive electrode is electrically connected to the titanium mesh electrode and the top electrode of the carbon fiber cloth, so as to form a steel mesh cathodic protection circuit.

7. The method for monitoring degradation and improving durability of a flotation tank in a seawater desalination plant according to claim 6, characterized in that: After the steel mesh cathodic protection loop is formed, the method further comprises: The electrochemical method is used to determine the corrosion immunity of the steel mesh in the seawater corrosion area of ​​the component under common seawater corrosion media and concentrations.

8. The method for monitoring degradation and improving durability of a flotation tank in a seawater desalination plant according to claim 1, characterized in that: In step S4, the electrical / thermal parameters of the testing electromechanical / thermal intelligent sensing layer include: The resistivity, impedance, capacitance and thermoelectric coefficient of the electromechanical / thermoelectric smart layer are tested respectively using a signal acquisition instrument, an LCR bridge or a thermoelectric coefficient acquisition instrument.

9. The method for monitoring degradation and improving durability of a flotation tank in a seawater desalination plant according to claim 8, characterized in that: After using a signal acquisition instrument, an LCR bridge or a thermoelectric coefficient acquisition instrument to test the resistivity, impedance, capacitance and thermoelectric coefficient of the electromechanical / thermoelectric smart layer, the method further includes: The electrical / thermal parameters are extracted using signal differential temperature compensation and band-pass filtering modulation post-processing techniques.

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