Resourceful treatment system and method for residual mud and muck

Abstract

The invention provides a resourceful treatment system and method for residual mud muck, and the method comprises the following steps: gradually adding CaO2 into the residual mud muck, carrying out stirring reaction at 20-60 DEG C for 1-48 hours, dynamically adjusting the adding rate of CaO2, and enabling the concentration of. OH to be 0.5-1.2 [mu] M to obtain pretreated muck; cTAB is evenly sprayed to the surface of the pretreated muck, stirring and shearing mixing are conducted for 10-30 min, the adding amount of CTAB and the stirring and shearing speed are adjusted, and muck subjected to mass transfer strengthening is obtained; the muck obtained after mass transfer strengthening is put into a mold to be subjected to vibration exhausting, then pressurization curing is conducted, the pressure ranges from 20 MPa to 30 MPa, and the pressure maintaining time ranges from 5 min to 10 min; and carrying out steam curing. According to the technical scheme, full-chain cooperative treatment of efficient pollutant removal, deep dehydration and high solidification body strengthening is achieved, and an efficient low-carbon solution is provided for urban bulk solid waste recycling.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental geotechnical engineering and solid waste resource utilization, and in particular to a system and method for processing residual mud and slag resources. Background Art

[0002] In the process of urbanization in my country, tunnel shield construction, subway construction and other projects generate more than 2 billion tons of high-clay residual mud and debris every year. The clay content (particle size <2μm) is generally higher than 40%, and the specific surface area is as high as 800m 2 / g (montmorillonite), with bound water accounting for 65%-70%, and a moisture content of ≥60% for a long time. It also suffers from complex pollution issues such as heavy metals (As, Pb), petroleum hydrocarbons, and residual construction additives (PAM, surfactants), creating a significant conflict between environmental risks and resource utilization. Current mainstream treatment technologies have the following core flaws:

[0003] 1. Traditional step-by-step processes are inefficient and lack synergy

[0004] The existing "dehydration-solidification-stabilization" step-by-step process uses a combination of centrifugal dehydration (water content reduced to 45%-50%) and cement solidification (addition 15%-20%), which has significant bottlenecks: (1) The process is lengthy: dehydration requires the addition of flocculants (PAM 0.5‰-1‰) and mechanical filtration for 48-72 hours, and solidification and curing for more than 7 days, with a total cycle of more than 10 days. (2) High energy consumption and cost: Desorption of bound water requires overcoming an activation energy of 15.2 kJ / mol, resulting in a processing cost of 120-150 yuan / ton, with thermal drying energy accounting for more than 60%. (3) Large performance fluctuations: The compressive strength of the solidified body is only 8-20 MPa (standard deviation ±4.2 MPa), and the heavy metal leaching concentration (such as As 0.15-0.3 mg / L) is close to the limit value (0.3 mg / L) of "GB 5085.3-2007".

[0005] 2. Single oxidation / curing technology has significant functional defects

[0006] Chemical oxidation technology: Although the Fenton method can degrade PAM (efficiency 70%-80%), the utilization rate of H2O2 is less than 30%, and Fe 2+ Residue>200mg / kg, prone to secondary pollution;

[0007] Alkali-activated solidification: Geopolymers made from slag / fly ash have a compressive strength of 25-30 MPa, but are unable to simultaneously degrade pollutants. Furthermore, the interlayer domain structure (1.2 nm) of high-clay slag hinders gel network penetration, resulting in a cracking rate of >15% in the solidified body.

[0008] Application limitations of calcium peroxide (CaO2): H2O2 and ·OH released by CaO2 face mass transfer efficiency attenuation (diffusion coefficient is only 35% of free solution), ROS quenching (Fe 2+ / humic acid quenching rate>60%) and pore clogging problems, the actual dehydration rate increased by less than 10%.

[0009] 3. The multi-scale mechanism is broken and lacks quantitative regulation

[0010] Molecular-pore scale separation: Existing technologies analyze ROS oxidation (e.g., EPR measurement of OH concentration) or pore mass transfer (e.g., mercury intrusion porosimetry) in isolation, without establishing cross-scale correlation models. For example, the confinement effect of montmorillonite interlayers increases the local concentration of H2O2 by 20%, but the increased tortuosity of the diffusion path causes the oxidant dosage to exceed the theoretical value by 40%-60%.

[0011] Lack of dynamic matching mechanism: dehydration and solidification stages affect Ca 2+ There is a timing conflict in demand, early Ca 2+ Used to compress the double layer (Zeta potential -35mV→-12mV), and external Ca supplementation is required in the later curing stage 2+ (Cost increased by 25%), the existing process cannot be dynamically adjusted;

[0012] Gap in intelligent control: Traditional parameter optimization relies on trial and error, and does not integrate ROS monitoring (such as FLIM imaging), mass transfer simulation (COMSOL multiphysics) and strength prediction (ML algorithm). The process robustness is poor, and the coefficient of variation of compressive strength is as high as 0.35.

[0013] The above mainstream processing technologies all face three major scientific challenges:

[0014] (1) Failure of ROS spatiotemporal synergy: The slow release of H2O2 and transient oxidation of OH cannot match the multi-stage requirements of pollutant degradation-dehydration-solidification;

[0015] (2) Pore-interface mass transfer barrier: The molecular sieving effect of nanopores (<2 nm) attenuates the effective concentration of ROS by 60%, and the double layer reconstruction energy barrier (ΔG>15 kJ / mol) inhibits the release of bound water;

[0016] (2) Lack of dynamic control of multiple processes: oxidant addition, Ca 2+ Migration and gel formation rates are disconnected, leading to a break in the process chain.

[0017] In general, existing technologies face technical bottlenecks in the treatment of high-clay sludge and debris, such as residual pollutants, low dehydration efficiency and poor solidification performance. Summary of the Invention

[0018] In response to the above technical problems, the present invention discloses a system and method for the resource processing of residual mud and slag. Based on the resource processing of high-clay residual mud and slag regulated by the coordinated regulation of calcium peroxide (CaO2), the oxidation-mass transfer-solidification coupling coordinated mechanism of reactive oxygen species (ROS) is used to achieve efficient removal of pollutants, deep dehydration and high strengthening of the solidified body in the whole chain coordinated processing, providing key technical support for the construction of "zero-waste cities".

[0019] To this end, the technical solution adopted in the present invention is:

[0020] A method for recycling residual mud and slag, comprising the following steps:

[0021] Step S1, gradually adding CaO2 to the residual mud and slag, stirring and reacting at 20-60°C for 1-48 hours; monitoring the ·OH concentration of the reaction system by electron paramagnetic resonance and fluorescent probe, dynamically adjusting the CaO2 addition rate to make the ·OH concentration 0.5-1.2 μM, and obtaining pretreated slag; wherein the total addition amount of CaO2 is 2%-10% of the dry weight of the residual mud and slag;

[0022] Step S2, uniformly spraying CTAB onto the surface of the pretreated soil and performing stirring and shear mixing for 10-30 minutes, dynamically monitoring the diffusion path of ROS using fluorescence lifetime imaging (FLIM), adjusting the dosage of CTAB and the stirring and shear rate to increase the effective diffusion coefficient of ROS in the soil to 60%-85% of that in pure water solution, thereby obtaining soil with enhanced mass transfer; wherein the amount of CTAB added is 0.2%-0.8% of the mass of the pretreated soil;

[0023] Step S3: placing the mass transfer enhanced slag into a mold for vibration degassing, adding 0.1%-0.5% sodium polyacrylate dispersant to adjust the surface charge distribution, and then pressurizing and curing at a pressure of 20-30 MPa for 5-10 minutes; and then steam curing.

[0024] As a further improvement of the present invention, step S1 further includes adding a citric acid buffer to adjust the pH value of the reactants to 9-11. Furthermore, the dosage of the citric acid buffer is 0.05-0.1 mol / L.

[0025] As a further improvement of the present invention, in step S1, the CaO2 is added in a gradient manner, with an initial addition of 4% of the dry weight of the residual mud and soil, and thereafter 2% of the dry weight of the residual mud and soil is added every 2 hours.

[0026] As a further improvement of the present invention, in step S1, the stirring speed is 50-150 rpm.

[0027] As a further improvement of the present invention, in step S1, the Ca content of the pre-treated slag is 2+ The concentration is 0.5-1.5mol / L.

[0028] As a further improvement of the present invention, in step S1, the physical and chemical indicators of the reaction system are monitored by an online pH / ORP sensor.

[0029] As a further improvement of the present invention, in step S1, the stirring reaction temperature is 20-30° C., and the stirring reaction time is 4-6 h.

[0030] As a further improvement of the present invention, in step S2, hexadecyltrimethylammonium bromide is evenly sprayed at a flow rate of 0.5-2 L / min, with a droplet size of 50-100 μm, so that the interlayer domain of montmorillonite in the slag is expanded to 2.5-3.0 nm.

[0031] As a further improvement of the present invention, in step S2, a high shear mixer is used for stirring and shear mixing, wherein the gap between the rotor and the stator of the high shear mixer is 0.2-0.5 mm, and the shear rate is 100-150 s -1 , the continuous processing time is 10-20min.

[0032] As a further improvement of the present invention, in step S2, each batch is sampled once, and a synchrotron radiation X-ray micro-tomography offline detection unit is used for three-dimensional pore network reconstruction.

[0033] As a further improvement of the present invention, in step S2, the migration path of H2O2 in the nanopores is tracked by FLIM, and the mass transfer parameters are optimized in combination with molecular dynamics simulation to obtain the effective diffusion coefficient of ROS.

[0034] As a further improvement of the present invention, in step S3, the vibration frequency of the vibration exhaust is 50-60 Hz, and the amplitude is 1-2 mm.

[0035] As a further improvement of the present invention, in step S3, the steam curing temperature is 60±5° C., the humidity is ≥95%, and the time is 24-48 hours.

[0036] As a further improvement of the present invention, in step S3, if the residual sludge is high-silicon-alumina sludge, nano-SiO2 sol is sprayed into the mass transfer enhanced sludge to enhance the crosslinking degree of the C-(A)-SH gel. Furthermore, the amount of the nano-SiO2 sol added is 0.5% to 1% of the mass of the mass transfer enhanced sludge.

[0037] As a further improvement of the present invention, in step S1, data of the reaction system is collected by an online pH / ORP sensor, and the temperature of the reaction system is monitored by a temperature probe. In step S3, the temperature and humidity of the steam curing are collected by a PID temperature control valve and a humidity sensor. The collected data of the online pH / ORP sensor, temperature probe, electron paramagnetic resonance and fluorescence probe, FLIM, PID temperature control valve and humidity sensor are analyzed by an intelligent control unit, and the NSGA-II algorithm is used to screen the Pareto optimal solution set, and the CaO2 dosage, CTAB dosage, stirring shear rate and curing temperature are dynamically adjusted.

[0038] Furthermore, the multi-objective optimization function adopted by the NSGA-II algorithm is shown in formula (1):

[0039]

[0040] Where F is the multi-objective optimization function, ROS is the concentration of reactive oxygen species, △W is the change in the weight update matrix, σ c is the compressive strength of the material.

[0041] The present invention discloses a system for the above-mentioned residual mud and slag resource treatment method, comprising: a pretreatment reactor, a mass transfer enhancement unit, and a solidification unit;

[0042] The pretreatment reactor is equipped with a feeding port, an online pH / ORP sensor, a temperature probe, an electron paramagnetic resonance and fluorescence probes; the mass transfer enhancement unit includes a mass transfer reactor, a high shear mixer and a FLIM probe are provided in the mass transfer reactor, and a CTAB sprayer is provided above the opening of the mass transfer reactor; the pretreatment reactor is connected to the inlet of the mass transfer reactor via a screw conveyor; and the curing unit includes a hydraulic molding machine, a mold, a vibration table and a steam curing chamber.

[0043] As a further improvement of the present invention, the pretreatment reactor is a double-layer stirred reactor, the inner wall of the double-layer stirred reactor is provided with a corrosion-resistant coating, the double-layer stirred reactor is provided with a double-layer turbine stirring paddle, an online pH / ORP sensor, a temperature probe, an electron paramagnetic resonance and a fluorescence probe, and the outlet of the automatic feeder is facing the feed port, which is used to achieve precise control of CaO2 gradient addition (initial 4% + 2% supplement every 2 hours) and citric acid buffer (0.05-0.1 mol / L).

[0044] As a further improvement of the present invention, the double-layer stirred reactor is provided with a jacket, heat transfer oil is provided in the jacket, and the jacket is connected to a circulation system;

[0045] As a further improvement of the present invention, the inclination angle of the screw conveyor is 30°.

[0046] As a further improvement of the present invention, the curing unit further includes a curing agent spraying device for spraying the nano-SiO2 sol.

[0047] As a further improvement of the present invention, the hydraulic forming machine has a built-in pressure sensor.

[0048] As a further improvement of the present invention, the residual mud and slag resource processing system includes an intelligent control unit, and the online pH / ORP sensor, temperature probe, electron paramagnetic resonance and fluorescence probe, FLIM, PID temperature control valve, humidity sensor, stirred reactor, automatic feeder, screw conveyor, high shear mixer, CTAB sprayer, steam curing chamber, and hydraulic molding machine are electrically connected. The intelligent control unit collects data from the online pH / ORP sensor, temperature probe, electron paramagnetic resonance and fluorescence probe, FLIM, PID temperature control valve and humidity sensor through a data collector to control the stirred reactor, automatic feeder, screw conveyor, high shear mixer, CTAB sprayer, steam curing chamber, and hydraulic molding machine.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] The technical solution of this invention achieves efficient pollutant degradation and removal through a coupled mechanism of dynamic reactive oxygen species (ROS) generation, optimized pore mass transfer, and controlled interfacial energy barriers. As(III) oxidation rates are ≥72%, PAM degradation rates are ≥85%, and heavy metal leaching concentrations are below the 50% limit set by GB 5085.3-2007. Deep dehydration is achieved, with a moisture content of ≤40%. The solidified material is highly reinforced, achieving a compressive strength of 18-25 MPa, a 100%-120% improvement over traditional processes, meeting standards for brickmaking (GB / T 5101-2017) and roadbed materials (JTGE40-2007). Furthermore, the system integrates electron paramagnetic resonance (EPR), synchrotron radiation microscopy (SR-μCT), and intelligent control algorithms, reducing treatment costs by 40% and energy consumption by 35%, providing a highly efficient and low-carbon solution for the resource utilization of large-scale urban solid waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 3D clay pore network diagram reconstructed by SR-μCT according to an embodiment of the present invention, where the black portion represents the montmorillonite interlayer domain and the white portion represents the kaolinite lattice pore.

[0052] Figure 2 This is a FLIM image of the spatiotemporal distribution of ROS according to an embodiment of the present invention, showing the H2O2 concentration gradient and the ·OH hotspot area.

[0053] Figure 3 This is a synergistic optimization curve of compressive strength and moisture content of the solidified body according to an embodiment of the present invention.

[0054] Figure 4 It is a schematic flow chart of a residual mud and slag resource processing system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0055] The preferred embodiments of the present invention are described in further detail below.

[0056] A method for recycling residual mud and slag, also a method for recycling high-clay residual mud and slag based on the coordinated regulation of calcium peroxide (CaO2), achieves the full-chain treatment of residual mud and slag, including pollutant degradation, deep dehydration, and high-strengthening of the solidified body, through the synergistic effect of dynamic generation of reactive oxygen species (ROS), optimization of pore confinement effects, and regulation of interfacial energy barriers. Specifically, the method includes:

[0057] Step S1, adding CaO2 to the residual mud and slag in a gradient manner, stirring and reacting at 20-30°C for 4-6 hours, the initial addition of CaO2 is 4% of the dry weight of the residual mud and slag, and then adding 2% of the dry weight of the residual mud and slag every 2 hours, and the total addition of CaO2 is 2%-10% of the dry weight of the residual mud and slag, and the stirring speed is 50-150rpm. The ROS generated by the reaction include H2O2, ·OH and O2· - The concentration of ·OH in the reaction system was monitored by electron paramagnetic resonance and fluorescence probe, and the CaO2 addition rate was dynamically adjusted to make the ·OH concentration 0.5-1.2μM. The physical and chemical indicators of the reaction system were monitored by online pH / ORP sensor. Finally, the pretreated slag was obtained, in which Ca 2+ The concentration is 0.5-1.5mol / L.

[0058] Initially, due to the hydrolysis of CaO2, the pH value of the reaction system is 8-12. During the reaction, a citric acid buffer is added to adjust the pH value of the reactants to 9-11. The dosage of the citric acid buffer is 0.05-0.1 mol / L.

[0059] In step S1, by regulating the CaO2 dosage (2%-10% dry basis), pH and temperature, a synergistic system of H2O2 slow-release oxidation (half-life 8.2h) and ·OH instantaneous strong oxidation (concentration 0.5-1.2μM) is constructed, namely, a ROS gradient oxidation system, to achieve targeted degradation of pollutants: ·OH preferentially attacks organic pollutants (such as the CN bond of PAM), H2O2 continuously oxidizes heavy metals (As(III)→As(V) conversion rate ≥72%), and O2 ·- Through electron transfer (Fe 3+ / Fe 2+By integrating electron paramagnetic resonance (EPR) and a fluorescent probe (Amplex UltraRed), the ROS concentration distribution is monitored in real time, and the CaO2 injection rate is dynamically adjusted to avoid hydrophilic rebound caused by excessive oxidation (maintaining a contact angle of ≥70°).

[0060] Step S2: Spray CTAB uniformly onto the surface of the pretreated soil at a flow rate of 0.5-2 L / min, with a droplet size of 50-100 μm and an amount of CTAB of 0.2%-0.8% of the mass of the pretreated soil, so that the interlayer domain of montmorillonite in the soil expands from 1.2 nm to 2.5-3.0 nm. A high shear mixer is used for stirring and shear mixing for 10-20 minutes at a shear rate of 100-150 s. -1 .

[0061] In this step, samples were taken once per batch and an offline detection unit using synchrotron radiation X-ray microtomography was used to reconstruct the three-dimensional pore network (resolution ≤ 50 nm). Figure 1 shown.

[0062] FLIM was used to dynamically monitor the diffusion path of ROS in nano-voids such as the interlayer domain of montmorillonite (1.2nm) and the lattice pores of kaolinite (<2nm). The FLIM imaging of the spatiotemporal distribution of ROS is shown in Figure 2. Figure 2 As shown, the migration path of H₂O₂ within the nanopores was tracked, and mass transfer parameters were optimized using molecular dynamics simulations to obtain the effective ROS diffusion coefficient. The CTAB dosage and stirring shear rate were then adjusted to increase the effective ROS diffusion coefficient in the slag to 60%-85% of that in the free solution, resulting in slag with enhanced mass transfer. In this step, by adjusting the CTAB dosage and stirring shear rate, the pore size distribution and surface charge density were adjusted to increase the effective ROS diffusion coefficient to 60%-85% of that in pure water. Furthermore, the proportion of pores with a diameter greater than 5 nm was optimized to 30%-50%, and the zeta potential was adjusted to -20mV to -10mV for surface charge density.

[0063] In this step, pore network reconstruction and chemical modification combined technology, confined mass transfer optimization and double-layer directional compression were used. Specifically:

[0064] Pore ​​network reconstruction-chemical modification combined technology: Based on the montmorillonite interlayer domain ratio identified by the synchrotron radiation X-ray microtomography offline detection unit (SR-μCT), which is 30%-40% in this embodiment, 0.2%-0.8% of the mass of the pretreated slag is added with cetyltrimethylammonium bromide (CTAB) for intercalation and pore expansion treatment, which expands the interlayer domain width from 1.2nm to 2.5-3.0nm; at the same time, the ROS migration rate is dynamically monitored by FLIM, and the CTAB dosage and stirring shear rate are feedback-adjusted.

[0065] Confined mass transfer optimization: Fluorescence lifetime imaging is used to track the migration path of H2O2 in nanopores, and molecular dynamics (MD) simulation is combined to optimize mass transfer parameters (such as increasing the local H2O2 concentration in the montmorillonite interlayer by 25%), thereby increasing the effective ROS diffusion coefficient to 60%-85% of that in the free solution.

[0066] Directional compression of the double layer: using Ca 2+ (Concentration 0.5-1.5 mol / L) compresses the double layer of clay particles, the Zeta potential rises from -35mV to -12mV, combined with ROS oxidation to destroy the surface hydration film, releasing bound water, and the release rate of weakly bound water T2 = 10-100ms is ≥75%.

[0067] In step S3, the enhanced mass transfer soil is placed in a mold and vibrated to remove air, reducing internal porosity. The vibration frequency is 50-60 Hz, with an amplitude of 1-2 mm. The soil is then pressurized and cured at a pressure of 20-30 MPa for 5-10 minutes. Steam curing is then performed at a temperature of 60±5°C and a humidity of ≥95% for 24-48 hours.

[0068] In this step, Ca generated by CaO2 hydrolysis 2 The double electrical layer is compressed by adding a 0.5-1.5 mol / L sodium polyacrylate dispersant (0.1%-0.5%) to the composite, modulating the surface charge distribution and raising the zeta potential from -35mV to -12mV. This simultaneously generates a C-(A)-SH gel, resulting in a solidified compressive strength of 18-25MPa and a bound water release rate of ≥65%, meeting standards for brickmaking (moisture content ≤40%) and roadbed materials (CBR ≥8%).

[0069] 3-5 samples are randomly inspected in each batch, and the material is automatically discharged after the compressive strength reaches the standard. The obtained solidified body compressive strength and moisture content synergistic optimization curve is as follows Figure 3 shown.

[0070] This step is the collaborative construction process of the gel network: Ca(OH)2 generated by the hydrolysis of CaO2 provides an alkaline environment to activate the silicate and Ca 2+The reaction generates C-(A)-SH gel; ROS oxidizes silicate minerals to release active silicon monomers (Si-OH density is reduced by 30%), increasing the cross-linking degree of the gel by 40% and the compressive strength to 18-25 MPa.

[0071] In this step, if the residual sludge is high-silicon-aluminum sludge, nano-SiO2 sol is sprayed into the mass transfer enhanced sludge to enhance the crosslinking degree of the C-(A)-SH gel. Furthermore, the amount of the nano-SiO2 sol added is 0.5%-1% of the mass of the mass transfer enhanced sludge.

[0072] Furthermore, this step also includes interfacial energy barrier regulation: X-ray photoelectron spectroscopy (XPS) is used to analyze the Si-O-Si / Si-OH reconstruction pattern on the clay surface, and low-field nuclear magnetic resonance (LF-NMR) is used to quantify the activation energy of bound water desorption (Ea is reduced from 15.2 kJ / mol to 9.8 kJ / mol), thereby achieving dynamic matching of dehydration and solidification.

[0073] In the above steps, step S1 collects data of the reaction system through an online pH / ORP sensor, and monitors the temperature of the reaction system through a temperature probe. In step S3, the temperature and humidity of the steam curing are collected through a PID temperature control valve and a humidity sensor. The system analyzes the collected data of the online pH / ORP sensor, temperature probe, electron paramagnetic resonance and fluorescence probe, FLIM, PID temperature control valve and humidity sensor through an intelligent control unit, uses the NSGA-II algorithm to screen the Pareto optimal solution set, and dynamically adjusts the CaO2 dosage, CTAB dosage, stirring shear rate and curing temperature.

[0074] The NSGA-II algorithm uses moisture content, compressive strength and treatment cost as a multi-objective function, as shown in formula (1). The number of iterations is 100-200 to generate a Pareto optimal solution set, the convergence threshold ΔF<0.05, and the treatment cost is reduced by 30%-40%.

[0075]

[0076] Where F is the multi-objective optimization function, ROS is the concentration of reactive oxygen species, △W is the change in the weight update matrix, σ c is the resulting compressive strength of the material.

[0077] A residual mud and slag resource treatment system, that is, a system using the residual mud and slag resource treatment method, such as Figure 4 As shown, the system includes the following core modules:

[0078] 1. Pretreatment reactor

[0079] The pretreatment reactor adopts a double-layer stirred reactor (volume 5-10m3 , 316L stainless steel), equipped with a corrosion-resistant coating (such as PTFE) to resist the alkaline environment (pH 8-12) generated by CaO2 hydrolysis.

[0080] The stirring system of the pretreatment reactor adopts a double-layer turbine stirring blade (blade diameter / kettle diameter ratio 0.3-0.5), a rotation speed of 50-150rpm, and a power of 7.5-15kW to ensure uniform mixing of the slag and the oxidant.

[0081] Parameter control unit:

[0082] The pretreatment reactor is integrated with an online pH / ORP sensor (accuracy ±0.1pH, sampling frequency 1Hz) and a Pt100 temperature probe (accuracy ±0.5°C), which provide real-time feedback to the PLC controller.

[0083] Dosing system: Equipped with an automatic dosing machine (accuracy ±0.5%) to achieve precise control of CaO2 gradient addition (initial 4% + 2% supplement every 2 hours) and citric acid buffer (0.05-0.1mol / L).

[0084] Temperature control design:

[0085] External jacket circulation system (heat transfer oil medium), temperature control range 20-60℃ (fluctuation ±2℃), response time ≤5min.

[0086] The materials after the reaction in the pretreatment reactor are transported to the mass transfer enhancement unit through a screw conveyor (inclination angle 30°, power 3kW). The screw conveyor has an inclination angle of 30°, a power of 3kW, and a residence time of ≤5min to avoid secondary agglomeration.

[0087] 2. Multi-scale mass transfer enhancement unit

[0088] The mass transfer enhancement unit includes a reactor equipped with a high shear mixer and a mass transfer monitoring system. A CTAB atomizing nozzle is provided above the opening of the reactor to evenly spray cetyltrimethylammonium bromide (CTAB, concentration 0.2%-0.8%) onto the surface of the slag, intercalating and expanding the pores of the montmorillonite interlayer domain (width expanded from 1.2nm to 2.5-3.0nm) to modify the pore structure.

[0089] The high shear mixer adopts a rotor-stator structure with a gap of 0.2-0.5 mm and a shear rate of 100-150 s. -1 , continuous processing time is 10-20min.

[0090] The mass transfer monitoring system includes an integrated fluorescence lifetime imaging (FLIM) probe (spatial resolution ≤ 50 nm) to capture the migration path of ROS (such as H2O2) in nanopores in real time, and the data is fed back to the intelligent control unit.

[0091] Synchrotron radiation X-ray micro-tomography (SR-μCT) offline detection unit with a resolution of ≤50 nm was used for 3D pore network reconstruction (one sampling test per batch).

[0092] 3. Curing unit, including:

[0093] Molding equipment, namely hydraulic molding machine and mold, the pressure of hydraulic molding machine is 20-30MPa, the holding time is 5-10min, and the mold specification is standard brick type (240×115×53mm) or roadbed aggregate (particle size 10-30mm).

[0094] Vibration table: used to place the mass transfer-enhanced soil into the mold for vibration degassing to reduce internal porosity. The vibration table has a frequency of 50-60 Hz and an amplitude of 1-2 mm, which assists in degassing and reduces internal porosity (≤5%).

[0095] Maintenance system:

[0096] Steam curing room, temperature 60±5℃, humidity ≥95%, time 24-48h, equipped with PID temperature control valve and humidity sensor (error ±3%).

[0097] Automatic curing agent spraying device: for high silicon-alumina slag, add 0.5%-1% nano-SiO2 sol to enhance the cross-linking degree of C-(A)-SH gel.

[0098] Strength testing mechanism: The hydraulic forming machine is equipped with a built-in pressure sensor (range 0-50MPa, accuracy ±0.5%FS). 3-5 samples are randomly inspected in each batch, and the material is automatically discharged when the compressive strength meets the standard.

[0099] 4. Intelligent control unit

[0100] (1) Structural aspects

[0101] Hardware configuration: Industrial-grade PLC (such as Siemens S7-1500), equipped with a multi-channel data acquisition card (sampling rate 1kHz), real-time processing of sensor signals.

[0102] Edge computing terminals (such as NVIDIA Jetson AGX Xavier) run the genetic algorithm (iterations 100-200 times, convergence threshold ΔF < 0.05).

[0103] Algorithm implementation:

[0104] Multi-objective optimization function:

[0105]

[0106] The NSGA-II algorithm was used to screen the Pareto optimal solution set and dynamically adjust the CaO2 dosage, CTAB concentration and curing temperature.

[0107] Human-computer interaction:

[0108] The touch screen operation interface (10.1 inches, IP65 protection grade) supports real-time curve display (such as pH, temperature, intensity trend) and fault alarm log.

[0109] Remote monitoring interface (4G / 5G module) supports cloud data storage and mobile access.

[0110] This embodiment adopts the "oxidation-mass transfer-curing" full chain coupling mechanism, based on ROS oxidation (degradation of pollutants), Ca 2+ The spatiotemporal synergistic laws of mass transfer (compression of the double electrical layer) and gel formation (curing enhancement) shorten the treatment cycle from >7 days to ≤48 hours through the timing strategy of "oxidation directional triggering-dehydration synchronous enhancement-curing delayed activation".

[0111] Secondly, this embodiment adopts nano-confined mass transfer enhancement technology, based on the multi-scale pore analysis of SR-μCT and FLIM, adopts a "pre-oxidation-sustained release enhancement" mass transfer strategy, and utilizes the confinement effect of the montmorillonite interlayer domain (1.2nm) to enhance the local ROS concentration, breaking through the bottleneck of the traditional homogeneous model prediction deviation >40%.

[0112] Third, this embodiment adopts a dynamic control model of the interfacial energy barrier to establish a quantitative relationship of "oxidation intensity (·OH concentration)-desorption energy (E_a)-gelation rate (dC / dt)", and realizes the simultaneous optimization of the bound water release rate (≥65%) and the compressive strength (≥18MPa) through the combination of LF-NMR and XPS technology.

[0113] The same residual mud and debris were treated using the aforementioned method and system, along with the traditional "dehydration-solidification-stabilization" process, which combines centrifugal dehydration (reducing the moisture content to 45%-50%) with cement solidification (at a dosage of 15%-20%). Table 1 compares the performance, treatment results, and other technical indicators of the resulting products.

[0114] Table 1

[0115] Technical indicators Traditional step-by-step process The present invention (embodiment) Processing cycle (h) >168 ≤48 Compressive strength (MPa) 8-20 18-25 Bound water release rate (%) 40-50 ≥65 PAM degradation rate (%) - ≥85 As(III) oxidation rate (%) - ≥72 Energy consumption (kJ / kg soil) 2800 1800 Cost (yuan / ton) 120-150 70-90

[0116] A comparison in Table 1 shows that the technical solution of this embodiment achieves efficient pollutant removal, with a PAM degradation rate ≥85%, an As(III) oxidation rate ≥72%, and heavy metal leaching concentrations below the 50% limit set by GB 5085.3-2007. It also achieves deep dehydration and high-strength curing: moisture content ≤40%, compressive strength 18-25 MPa (a 100%-120% improvement over traditional processes), meeting standards for brickmaking (GB / T 5101-2017) and roadbed materials (JTG E40-2007). It also offers low-carbon economics: processing costs are 70-90 yuan / ton (a 40% reduction), and carbon emissions are 60% lower than cement curing.

[0117] The above is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A method for recycling residual mud and slag, characterized by: The steps include: Step S1, gradually adding CaO2 to the residual mud and slag, stirring and reacting at 20-60°C for 1-48 hours; monitoring the ·OH concentration of the reaction system by electron paramagnetic resonance and fluorescent probe, dynamically adjusting the CaO2 addition rate to make the ·OH concentration 0.5-1.2 μM, and obtaining pretreated slag; wherein the total addition amount of CaO2 is 2%-10% of the dry weight of the residual mud and slag; Step S2: evenly spraying CTAB onto the surface of the pretreated soil and performing stirring and shear mixing for 10-30 minutes. FLIM is used to dynamically monitor the diffusion path of ROS, and the dosage of CTAB and the stirring and shear rate are adjusted to increase the effective diffusion coefficient of ROS in the soil to 60%-85% of that in pure water solution, thereby obtaining soil with enhanced mass transfer. The amount of CTAB added is 0.2%-0.8% of the mass of the pretreated soil. Step S3: placing the mass transfer enhanced slag into a mold for vibration degassing, adding 0.1%-0.5% sodium polyacrylate dispersant to adjust the surface charge distribution, and then pressurizing and curing at a pressure of 20-30 MPa for 5-10 minutes; and then steam curing.

2. The method for recycling residual mud and slag according to claim 1, characterized in that: In step S1, a citric acid buffer is added to adjust the pH value of the reactants to 9-11; the dosage of the citric acid buffer is 0.05-0.1 mol / L.

3. The method for recycling residual mud and slag according to claim 2, characterized in that: In step S1, the CaO2 is added in a gradient manner, with an initial addition of 4% of the dry weight of the residual mud and soil, and then 2% of the dry weight of the residual mud and soil is added every 2 hours; the stirring speed is 50-150rpm; the CaO2 of the pre-treated soil is 2+ The concentration is 0.5-1.5 mol / L; In step S1, the physical and chemical indicators of the reaction system are monitored by an online pH / ORP sensor.

4. The method for recycling residual mud and slag according to claim 1, characterized in that: In step S2, cetyltrimethylammonium bromide is evenly sprayed at a flow rate of 0.5-2 L / min, with a droplet size of 50-100 μm, so that the interlayer domain of montmorillonite in the slag is expanded to 2.5-3.0 nm.

5. The method for recycling residual mud and slag according to claim 4, characterized in that: In step S2, a high shear mixer is used for stirring and shear mixing, wherein the gap between the rotor and the stator of the high shear mixer is 0.2-0.5 mm and the shear rate is 100-150 s -1 , the continuous processing time is 10-20min; each batch is sampled once, and a synchrotron radiation X-ray microtomography offline detection unit is used to reconstruct the three-dimensional pore network; the migration path of H2O2 in the nanopores is tracked by FLIM, and the mass transfer parameters are optimized by molecular dynamics simulation to obtain the effective diffusion coefficient of ROS.

6. The method for recycling residual mud and slag according to claim 1, characterized in that: In step S3, the vibration frequency of the vibration exhaust is 50-60 Hz, and the amplitude is 1-2 mm; the temperature of the steam curing is 60±5° C., the humidity is ≥95%, and the time is 24-48 hours.

7. The method for recycling residual mud and slag according to claim 6, characterized in that: In step S3, if the residual mud is high-silicon-aluminum mud, nano-SiO2 sol is sprayed into the mud after mass transfer enhancement to enhance the crosslinking degree of C-(A)-SH gel; wherein the addition amount of the nano-SiO2 sol is 0.5%-1% of the mass of the mud after mass transfer enhancement.

8. The method for recycling residual mud and slag according to any one of claims 1 to 7, characterized in that: Also includes: In step S1, data of the reaction system is collected through an online pH / ORP sensor, and the temperature of the reaction system is monitored through a temperature probe. In step S3, the temperature and humidity of the steam curing are collected through a PID temperature control valve and a humidity sensor. The collected data of the online pH / ORP sensor, temperature probe, electron paramagnetic resonance and fluorescence probe, FLIM, PID temperature control valve and humidity sensor are analyzed by an intelligent control unit, and the Pareto optimal solution set is screened using the NSGA-II algorithm to dynamically adjust the CaO2 dosage, CTAB dosage, stirring shear rate and curing temperature. The multi-objective optimization function used by the NSGA-II algorithm is shown in formula (1): Where F is the multi-objective optimization function, ROS is the concentration of reactive oxygen species, △W is the change in the weight update matrix, σ c is the compressive strength of the material.

9. A system for recycling residual mud and slag, characterized in that: The residual mud and slag resource treatment method according to any one of claims 1 to 8 is used for treatment, wherein the residual mud and slag resource treatment system comprises: a pretreatment reactor, a mass transfer enhancement unit, and a solidification unit; The pretreatment reactor is equipped with a feeding port, an online pH / ORP sensor, a temperature probe, an electron paramagnetic resonance and fluorescence probes; the mass transfer enhancement unit includes a mass transfer reactor, a high shear mixer and a FLIM probe are provided in the mass transfer reactor, and a CTAB sprayer is provided above the opening of the mass transfer reactor; the pretreatment reactor is connected to the inlet of the mass transfer reactor via a screw conveyor; and the curing unit includes a hydraulic molding machine, a mold, a vibration table and a steam curing chamber.

10. The residual mud and slag resource processing system according to claim 9 is characterized in that: The pretreatment reactor is a double-layer stirred reactor, the inner wall of which is provided with a corrosion-resistant coating, and the double-layer stirred reactor is provided with a double-layer turbine stirring paddle, an online pH / ORP sensor, a temperature probe, an electron paramagnetic resonance and a fluorescence probe. The outlet of the automatic feeder faces the feed port, and the double-layer stirred reactor is provided with a jacket, and heat-conducting oil is provided in the jacket, and the jacket is connected to a circulation system; The inclination angle of the screw conveyor is 30°; The curing unit further comprises a curing agent spraying device for spraying nano-SiO2 sol. The hydraulic forming machine has a built-in pressure sensor; The residual mud and slag resource processing system includes an intelligent control unit. The online pH / ORP sensor, temperature probe, electron paramagnetic resonance and fluorescence probe, FLIM, PID temperature control valve, humidity sensor, stirred reactor, automatic feeder, screw conveyor, high shear mixer, CTAB sprayer, steam curing chamber, and hydraulic molding machine are electrically connected. The intelligent control unit collects data from the online pH / ORP sensor, temperature probe, electron paramagnetic resonance and fluorescence probe, FLIM, PID temperature control valve, and humidity sensor through a data collector to control the stirred reactor, automatic feeder, screw conveyor, high shear mixer, CTAB sprayer, steam curing chamber, and hydraulic molding machine.

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