Directional allocation of hydrolysis liquid of kitchen waste and LDH carrier synergistic treatment process of bio-carbon source

Abstract

The present application relates to the technical field of water treatment, and discloses a kind of kitchen waste hydrolysate directional deployment biological carbon source and LDH carrier synergistic treatment process, comprising: adjusting the molar ratio of binary and unary organic acid root in primary hydrolysate to 0.15 to 0.35, mixing the deployed biological carbon source with layered double hydroxide carrier and controlling the Reynolds number to 300 to 800, introducing effluent to adjust the pH of mixed solution to 6.5 to 8.5 periodically, inducing the change of hydroxyl dissociation state on the surface of carrier layer, using the generated potential gradient to drive binary organic acid root into the interlayer of carrier, and discharging the loaded carrier into the biochemical system.The present application induces charge fluctuation by pH switching, effectively solves the problem of carrier orifice closure, improves the utilization rate of active sites, and realizes the matching of carbon source release and synergistic phosphorus removal.

Description

Technical Field

[0001] This invention belongs to the field of water treatment technology, and in particular relates to a process for the synergistic treatment of food waste hydrolysate with a biocarbon source and an LDH carrier. Background Technology

[0002] Currently, deep denitrification and phosphorus removal in urban wastewater relies on a stable external carbon source. The existing treatment process utilizes acidic hydrolysate from the anaerobic fermentation of kitchen waste as an alternative carbon source, combined with a layered double hydroxide carrier with anion exchange function. The layered double hydroxide, with its unique interlayer structure, acts as a storage and release matrix for biological carbon sources while removing phosphates from wastewater. However, the composition of kitchen waste hydrolysate is complex. Volatile fatty acids and phosphates in the wastewater dynamically compete when entering the carrier interlayer. High-affinity organic acid anions tend to accumulate at the edges of the carrier crystals, creating steric hindrance and causing pore blockage, thus blocking the migration path of anions into the crystal interior. This results in the active sites in the central region of the carrier being idle, leading to low carrier utilization. Simultaneously, loosely adsorbed organic acid anions undergo uncontrolled burst shedding after entering the wastewater treatment system, causing a time mismatch between the carbon source release rate and the metabolic needs of denitrifying bacteria, resulting in carbon source waste and increasing the risk of COD exceeding standards in the effluent.

[0003] The industry has adopted methods such as increasing the stirring rate or extending the contact conditioning time to improve the load distribution. However, simply improving the physical pore morphology of the carrier is difficult to cope with the dynamic mass transfer resistance of complex biochemical systems. For example, Chinese invention patent application CN104703918A discloses a layered double hydroxide modification, which uses acetone hydrophilic organic solvent to replace interlayer water molecules to prevent particle agglomeration during the drying process and increase the specific surface area and pore volume of the material. The solvent replacement static pretreatment effect is limited to the initial preparation stage of the material. When facing high viscosity and high organic load kitchen waste hydrolysate, it lacks a dynamic potential driving mechanism that responds to environmental changes in real time. The pre-constructed open pore structure is prone to steric hindrance accumulation at the pore opening by high affinity organic acid radicals or colloidal substances in the early stage of contact. The deep internal active sites of the modification cannot be utilized, and the method does not solve the problem of interface deactivation caused by oil film encapsulation during long-term operation.

[0004] Therefore, the technical problem to be solved by this invention is how to overcome interlayer diffusion barriers and achieve orderly storage and directional release of carbon sources by regulating the interfacial interaction logic between hydrolysate components and carriers. Summary of the Invention

[0005] This invention provides a process for the targeted formulation of biocarbon source and LDH carrier for the synergistic treatment of kitchen waste hydrolysate, comprising the following steps:

[0006] Step S101, directional blending step: obtain the primary hydrolysate produced by anaerobic fermentation of kitchen waste through solid-liquid separation; add exogenous acetic acid or propionic acid to the primary hydrolysate according to the total volatile fatty acid concentration in the primary hydrolysate; adjust the molar ratio of dibasic organic acid ions to monobasic organic acid ions in the primary hydrolysate to 0.15 to 0.35 to obtain a directional blended biological carbon source.

[0007] Step S102, the mixing and contacting step, involves adding powdered LDH carrier to the contact conditioning tank and injecting a directionally formulated biocarbon source into the contact conditioning tank. The Reynolds number of the mixture in the contact conditioning tank is controlled to be between 300 and 800 by adjusting the rotation speed of the stirring equipment in the contact conditioning tank.

[0008] Step S103, Interlayer Exchange Enhancement Step: During the mixing and contacting step, effluent from the biochemical system is introduced into the contact conditioning tank to periodically switch the pH value of the mixed solution between 6.5 and 8.5. The surface charge density of the LDH carrier is adjusted by changing the hydroxyl dissociation state on the surface of the LDH carrier layer. The potential gradient formed between the mixed solution and the LDH carrier layer drives the directional distribution of the dibasic organic acid anions in the biological carbon source into the interlayer interior of the LDH carrier.

[0009] Step S104, the synergistic phosphorus removal step, involves discharging the loaded LDH carrier into the anoxic zone of the biochemical system. The phosphate in the anoxic zone of the biochemical system undergoes ion exchange with the organic acid anions between the LDH carrier layers. While releasing a directionally distributed biological carbon source into the anoxic zone of the biochemical system, the phosphate in the anoxic zone of the biochemical system is adsorbed.

[0010] Preferably, in step S101, while adjusting the organic acid components, a polyhydroxy polyol is added to the primary hydrolysate to make the mass concentration of the polyhydroxy polyol in the directionally adjusted biocarbon source between 50 mg / L and 150 mg / L; the polyhydroxy polyol forms a polarity regulating layer on the surface of the LDH carrier to limit the diffusion of mono-inorganic anions in the mixture into the interlayer of the LDH carrier.

[0011] Preferably, in step S102, a magnesium-aluminum bimetallic hydroxide is selected as the LDH carrier, and the molar ratio of Mg to Al in the cations of the LDH carrier is 2 to 4; the concentration of the LDH carrier in the contact conditioning tank is controlled to be 200 mg / L to 600 mg / L, and the mass ratio of the bio-carbon source to the LDH carrier is 20:1 to 50:1.

[0012] Preferably, in step S103, the single fluctuation cycle of the pH value Hydraulic residence time of the mixture in the contact conditioning tank The following relationship must be satisfied: in, It represents a single fluctuation period, with the unit being hours (h). The preset residence time of the mixture in the contact conditioning tank is expressed in hours (h). The preset number of cycle switching times, and It is an integer between 3 and 6.

[0013] Preferably, before performing the targeted formulation step, a transition metal enrichment step is also included: using a membrane separation unit to retain iron ions, manganese ions and nickel ions in the primary hydrolysate, adjusting the total molar concentration of transition metal ions in the targeted formulated biocarbon source to 0.05 mmol / L to 0.2 mmol / L, so that the transition metal ions are loaded onto the surface defect sites of the LDH support along with the binary organic acid anions.

[0014] Preferably, after the LDH carrier enters the biochemical system, the redox potential fluctuations generated when the biochemical system switches between anoxic and aerobic conditions are used to induce transition metal ions to generate free radicals, thereby oxidizing and stripping the extracellular polymers deposited on the surface of the LDH carrier.

[0015] Preferably, in step S102, the rotation speed of the stirring device is 40 r / min to 120 r / min.

[0016] Preferably, the sludge retention time of the LDH carrier in the anoxic zone of the biochemical system is controlled. The treatment period is 12 to 20 days. Monitor the total phosphorus concentration in the effluent from the secondary sedimentation tank of the biochemical system. If the total phosphorus concentration exceeds 0.5 mg / L, increase the initial dosage of LDH carrier in step S102 by 5% to 10%.

[0017] Preferably, in step S101, the dibasic organic acid anions include at least one of the following: succinate, malate, and oxalate; by adjusting the proportion of the dibasic organic acid anions, the distribution density of the directionally formulated biocarbon source between the LDH carrier layers is adapted to the surface charge density of the layers.

[0018] Preferably, before the mixed liquor enters the anoxic zone of the biochemical system, a degassing step is also included: using an aeration unit to remove dissolved carbon dioxide from the mixed liquor and adjusting the alkalinity of the mixed liquor to 200 mg / L to 400 mg / L.

[0019] Compared with existing technologies, the present invention's process for the synergistic treatment of food waste hydrolysate with a targeted blending of biological carbon source and LDH carrier has the following advantages:

[0020] 1. In the synergistic treatment of biological carbon source and LDH carrier, by directionally adjusting the ratio of dicarboxylic acid to monovalent volatile fatty acid in the hydrolysate, and utilizing the dual-site anchoring effect of dicarboxylic acid between the layered double hydroxide plates, an organic acid skeleton with spatial support function is constructed inside the carrier. This widens and maintains the interlayer spacing, avoiding the pore blockage phenomenon caused by the rapid accumulation of high-affinity organic acid anions at the crystal edges. This allows monovalent volatile fatty acids in the hydrolysate to permeate into the central region of the carrier along the physical channels opened by the dicarboxylic acid, achieving full-domain saturation loading of active sites. This increases the carrier's carbon source storage capacity, transforming the carbon source release mode in the anoxic section of wastewater from a sudden shedding to a linear constant-rate release that matches the denitrification rate, thus reducing the load fluctuation of the biochemical system.

[0021] 2. By utilizing the long-chain fatty acids and polyhydroxy polyols associated with the hydrolysate of kitchen waste, a composite shielding system with both steric hindrance and charge repulsion functions is constructed on the carrier surface. The long-chain fatty acids, with their amphoteric molecular structure, form a hydrophobic shielding layer at the edge of the carrier grains, preventing the deposition of large molecular proteins, oils, and colloidal substances in the wastewater on the carrier surface to form a bio-passivation film. Meanwhile, the polyhydroxy polyols form a hydrated dipole shielding layer through the hydrogen bond network between the hydroxyl groups and the surface of the layers. The directional arrangement of water molecules generates steric hindrance, restricting the random diffusion of monobasic anions with small hydration radii, such as chloride ions, into the crystal lattice. This ensures that phosphates with specific orientation tendencies can be directionally introduced into the interlayer for replacement, improving the system's operational stability under high salinity and high organic load environments.

[0022] 3. By enriching trace transition metal ions separated from kitchen waste and anchoring them synchronously with organic acid radicals at surface defect sites on the carrier, a catalytically active micro-reaction center is constructed at the carrier interface. Utilizing the endogenous redox potential fluctuations generated when the wastewater treatment system switches between anoxic and aerobic conditions, trace free radicals are induced to generate and trigger in-situ oxidation reactions. These reactions degrade and strip away residual grease and extracellular polymers accumulated on the carrier surface, maintaining the ion penetration performance of the carrier interface. This achieves long-term online recovery of carrier activity in complex wastewater environments, avoids phosphorus removal efficiency degradation caused by surface scaling, and extends the effective service life of the carrier. Attached Figure Description

[0023] Figure 1 This is a flow chart of the process for the targeted formulation of kitchen waste hydrolysate and the synergistic treatment with LDH carrier according to the present invention;

[0024] Figure 2 This is a time-series diagram of the interlayer exchange enhancement and microscopic interaction mechanism based on pH periodic switching, as described in this invention. Detailed Implementation

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

[0026] It should be noted that all directional and positional terms used in this invention, such as: up, down, left, right, front, back, vertical, horizontal, inner, outer, top, low, lateral, longitudinal, center, etc., are only used to explain the relative positional relationship and connection between components in a specific state (as shown in the accompanying drawings). They are only for the convenience of describing this invention and do not require that this invention be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention. In addition, the descriptions of "first," "second," etc., in this invention are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly indicating the number of technical features indicated.

[0027] In the description of this invention, unless otherwise explicitly specified and limited, the terms installation, connection, and linking should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to the internal communication between two components. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0028] In the description of this specification, references to the terms "an embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example, and the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0029] This invention provides a process for the targeted formulation of biological carbon sources and synergistic treatment of food waste hydrolysate with LDH carriers. By controlling the composition of the primary hydrolysate produced from the anaerobic fermentation of food waste, and utilizing the interlayer ion exchange and charge relaxation effect of the LDH carrier, precise carbon source release and simultaneous phosphate adsorption are achieved in the wastewater biochemical treatment system. This includes targeted formulation of the primary hydrolysate, mixed loading, enhanced interlayer exchange, and synergistic phosphorus removal by the biochemical system. This process addresses the high concentration of volatile fatty acids in the food waste hydrolysate. With phosphates in wastewater To address the competitive adsorption problem at active sites, a targeted formulation process was implemented to obtain the primary hydrolysate from the anaerobic fermentation of kitchen waste through solid-liquid separation; based on the content of the primary hydrolysate... The mass concentration of the primary hydrolysate is adjusted by supplementing it with exogenous acetic acid or propionic acid to regulate the molar ratio of dibasic organic acid ions to monobasic organic acid ions in the primary hydrolysate to the range of 0.15 to 0.35, thereby obtaining a targeted bio-carbon source. The dibasic organic acid ions include at least one of succinate, malate, or oxalate. During the formulation process, the redox potential of the second phase of the anaerobic fermentation system is monitored and maintained below -250 mV, and the dibasic organic acid is enriched by utilizing the shift in the microbial metabolic pathway. Through the dual-site anchoring effect of the dibasic organic acid ions between LDH layers, a framework with spatial support function is constructed inside the carrier.

[0030] against The system addresses the technical challenge of carriers being prone to pore blockage and low utilization of internal active sites in complex wastewater electrolyte environments. It employs a flow-field controlled mixing and loading procedure to transport powdered carriers... The carrier is added to the contact conditioning tank, and the directionally formulated biocarbon source is injected into the contact conditioning tank; the rotation speed of the stirring equipment is adjusted to... to To control the Reynolds number of the mixture, i.e. exist to between; The concentration of the carrier added in the contact conditioning tank is to And targeted allocation of biocarbon sources and The mass ratio of the carrier is maintained at to Between; utilizing the shear force of the flow field to keep the carrier particles in a fully suspended state, providing a stable mass transfer interface for subsequent deep ion migration; to ensure that the flow field state during the mixing contact process satisfies the Reynolds number. For process requirements of 300 to 800, execute the parameter calibration procedure, Reynolds number The calculation formula is determined based on the fluid motion state equation within the stirred tank, as follows: ,in The density of the mixture is expressed in units of fluid density. The measured density value of the primary hydrolysate after solid-liquid separation was obtained. The rotational speed of the agitator blades in the mixing equipment, in units ; Characteristic diameter of the agitator blade, in units of For standard blades, the outer edge rotation diameter is used; for non-standard blades, the equivalent hydraulic diameter is used. The dynamic viscosity of the mixture is expressed in units of... The process temperature is 15. Up to 25 Viscosity of the primary hydrolysate was measured, and the mixed solution in the contact conditioning tank was measured before project implementation. and Reference value; Select the characteristic diameter of the agitator blades based on the geometry of the contact conditioning tank. ; Calculate the corresponding rotational speed based on the formula The range of values ​​ensures that the flow field is in a transitional flow state, and the transitional flow generates controlled shear force to maintain the suspension of the LDH carrier and renew the liquid film on the particle surface.

[0031] The electrostatic repulsion barrier generated by the surface charge density of the carrier plates limits the saturation loading of the carbon source. An interlayer exchange enhancement procedure based on charge relaxation is introduced. During mixed loading, effluent from the biological system is introduced into the contact conditioning tank to regulate the mixed liquor. Value at to Periodic switching occurs between them; A single fluctuation cycle of the value Hydraulic residence time of the mixture in the contact conditioning tank The following relationship must be satisfied: ,in, For a single fluctuation period, the unit is ; The preset residence time of the mixture in the contact conditioning tank, in units of ; The preset number of cycle switching times, and for to Integers between; through Value fluctuation changes The hydroxyl dissociation state on the surface of the carrier layer is adjusted to regulate the surface charge density, and the mixture is used in conjunction with... The potential gradient formed between the carrier layers drives the diffusion of binary organic acid anions from the bio-carbon source towards the central region of the carrier layers, thereby activating the active sites. Under high solids content conditions in the contact conditioning tank, an online monitoring feedback system based on the flow current (SC) is used to replace offline Zeta potential measurement. The procedure is based on the double-layer compression theory, characterizing the electrokinetic potential of the particle surface by measuring the induced current generated when charged particles move in a shear field. This includes a flow current detector installed on the circulation pipeline of the contact conditioning tank. During the process start-up phase, a correlation calibration step is performed: a mixed solution sample is collected from the contact conditioning tank, and the Zeta potential is measured by electrophoretic light scattering in a laboratory environment. Synchronously record the online instrument current readings at the sampling time. Multiple data pairs were obtained by adjusting the sample pH value within the range of pH 6.5 to 8.5, and a linear regression model was constructed. and Transformation function In actual operation, the controller collects the current readings of the current-carrying device in real time. Using conversion functions The controller calculates the current surface potential state. When the calculated potential value deviates from the preset target adsorption potential range (e.g., +20mV to +30mV) by more than 10%, the controller automatically fine-tunes the inlet flow rate of the biochemical system or the dosage of acid-base regulator. This method solves the problem of optical measurement obstruction in turbid systems and realizes real-time quantitative monitoring of the surface charge density of the carrier.

[0032] The entry of binary organic acid groups into the LDH interlayer is driven by periodic pH switching. The mechanism is based on the electromigration term in the Nernst-Planck equation. In the low pH stage (pH 6.5), metal hydroxide groups on the LDH interlayer surface... and The protonation reaction increases the positive charge density on the surface of the laminate. Increased surface charge density creates an enhanced electrostatic field at the solid-liquid interface. For negatively charged binary organic acid anions, this electrostatic field provides a driving force for the electric field pointing into the interlayer. The calculation relationship is as follows: ,in The effective charge of the anion in a diprotic organic acid is expressed in units of... ; For the surface charge density of the laminate Determines the local electric field strength, unit electric field driving force Overcoming diffusion resistance and pore steric hindrance within the confined ion space, the deprotonated charge density on the surface of the laminate decreases at the high pH stage (pH 8.5), weakening electrostatic attraction. Organic acid anions that have entered the interlayer diffuse deeper into the crystal lattice under the influence of concentration gradient, completing site rearrangement. An active transport process, similar to a charge pump, is achieved through alternating protonation and deprotonation cycles, ensuring deep utilization of active sites. To address the issue of the carrier being susceptible to high salt interference and biofilm passivation during long-term operation, the system simultaneously constructs interface shielding and self-cleaning centers during the directional formulation stage. Multi-hydroxy polyols are added to the primary hydrolysate, ensuring that the mass concentration of multi-hydroxy polyols in the directionally formulated biocarbon source is [missing information]. to Polyhydroxy polyols in A polarity regulation layer is formed on the carrier surface, utilizing steric hindrance to restrict the random diffusion of monolithic inorganic anions into the interlayer. A membrane separation unit retains iron, manganese, and nickel ions from the primary hydrolysate, adjusting the total molar concentration of transition metal ions in the bio-carbon source. to Transition metal ions are loaded onto the binary organic acid anions. Surface defect sites of the carrier.

[0033] During the synergistic phosphorus removal stage, the load is completed. The carrier is discharged into the anoxic zone of the biochemical system, utilizing the phosphate in the anoxic zone to react with... Organic acid ions between the carrier layers undergo ion exchange, releasing carbon sources to the biological system while adsorbing phosphates in the wastewater; this controls the anoxic zone within the biological system. The sludge retention time of the carrier, i.e. for to Monitor the total phosphorus concentration in the effluent from the secondary sedimentation tank. If the total phosphorus concentration exceeds... Then according to to The proportion increased The amount of carrier added; before entering the biochemical system, the dissolved carbon dioxide in the mixed liquor is removed by the aeration unit, and the alkalinity is adjusted to... to After the carrier enters the biochemical system, the redox potential fluctuations generated by switching between anoxic and aerobic conditions induce free radicals in surface-anchored transition metal ions, which then oxidize and strip extracellular polymers deposited on the carrier surface in situ. A controlled self-cleaning mechanism is constructed using differences in microscopic reaction kinetics and steric hindrance effects, allowing transition metal ions anchored at defect sites on the LDH surface to generate free radicals. , As a Fenton-like reaction catalytic center, it catalyzes the generation of short-lived hydroxyl radicals from dissolved oxygen or endogenous peroxides in water under the induction of ORP fluctuations in the biochemical system. The interlayer spacing of the LDH carrier is 0.8nm to 1.5nm, which is smaller than the size of the extracellular polymer macromolecule EPS. EPS is only attached to the outer surface of the carrier. The dibasic organic acid anions have been pre-intercalated into the interlayer of the carrier through the preceding steps. The extremely short mean free path and high reactivity of free radicals limit the oxidation to the Debye length range of the outer surface of the carrier. This results in free radicals preferentially attacking and degrading the macromolecular EPS film layer covering the outer surface of the carrier, restoring the permeability of the carrier pores. The bio-carbon source located inside the interlayer is physically shielded by the layer structure and protected from direct oxidation attack by free radicals. The outer surface oxidation and the inner interlayer protection space selectively solve the problem of compatibility between descaling and carbon storage.

[0034] Example 1: In a centralized wastewater treatment facility for catering establishments, the influent total phosphorus concentration is at... to Fluctuations between these ranges are due to the fact that the proportion of volatile fatty acid components in the primary hydrolysate shows a trend towards a single monocarboxylic acid, varying with the source of the kitchen materials. Direct addition of powdered form... When the carrier is used, high-affinity monocarboxylic acid anions occupy the active sites on the outer edge of the carrier and create steric hindrance. A dense organic coating layer forms on the carrier surface, restricting the migration of ions into the internal pores of the carrier, resulting in a lower phosphorus removal capacity utilization rate than that of the carrier. Furthermore, the carbon source experiences a burst release due to unstable surface adsorption, resulting in a higher total phosphorus concentration in the effluent of the biological system than expected. Furthermore, denitrification efficiency decreases. To address the mass transfer resistance caused by carrier surface passivation and pore blockage, the proposed solution obtains the primary hydrolysate through solid-liquid separation, determines the total volatile fatty acid concentration using an online monitoring unit, replenishes the primary hydrolysate with succinic acid as a dicarboxylic acid, and adjusts the molar ratio of dicarboxylic organic acid anions to monocarboxylic organic acid anions to a certain value. To obtain a targeted biocarbon source; to mix the targeted biocarbon source with a mass concentration of powder The carrier is injected into the contact conditioning tank, and the stirring speed is adjusted to adjust the Reynolds number of the mixture in the tank. Stable at The structure utilizes the dual-site anchoring effect of dibasic organic acid anions between the layers to form a supporting framework; simultaneously, it leverages the iron and manganese ions present in the primary hydrolysate to control the total molar concentration of transition metal ions within a specific range. And anchor it to the defect site on the carrier surface.

[0035] During the mixing and contact process, the system adjusts the return flow rate of the effluent from the biological system to regulate the mixing liquid in the contact equalization tank. Value at to The system switches between these states periodically, with a set number of cycles. for This process generates a charge relaxation effect, lowering the electrostatic repulsion barrier for organic acid anions migrating to the interlayer center, and inducing hydrolysate components to fill vacancies within the crystal grains. When the loaded carrier is discharged into the anoxic zone of the biological system, phosphates with higher charge density in the wastewater act as replacement factors, entering the interlayer and driving the uniform release of pre-loaded organic acid anions into the water for denitrifying bacteria metabolism. Simultaneously, the potential fluctuations generated by switching between anoxic and aerobic conditions in the biological system induce surface-anchored transition metal ions to generate free radicals, which then peel off the attached oils from the carrier surface. Ultimately, the total phosphorus concentration in the effluent from the biological system stabilizes at [value missing]. The following is a breakdown of the utilization rate of the active site of the vector. Upgraded to .

[0036] Example 2: In a scenario demonstrating the advanced treatment of restaurant wastewater containing high concentrations of chloride ions and emulsified grease interference, the system faces a chloride ion mass concentration of... to High salinity environment impact and the total phosphorus concentration in the influent is maintained at High position; using volume as A continuous flow biochemical reactor equipped with a temperature control accuracy of The heating device and the sampling frequency are Water quality monitoring sensor; the test process actively introduced a signal-to-noise ratio of To simulate complex industrial environments, fluctuations in the primary hydrolysate are controlled by adjusting the molar ratio of dibasic to monobasic organic acid anions. exist to They are distributed in a gradient and in coordination with each other. Pulse-induced load procedure; molar ratio The value of directly determines the interlayer support strength and the proportion of effective adsorption sites, as well as the number of periodic switching cycles. Setting a balance between charge relaxation driving force and system return energy consumption; when for And the alkalinity of the mixture is At that time, determine exist to Switching between parameters improves mass transfer efficiency; Table 1 is a comparison table of directional adjustment parameter gradients and collaborative processing performance, presenting and including... The operating data of the experimental group and the control group were collected in an environment with suspended oil, and the intermediate characteristic value was selected as the interlayer load density.

[0037] Table 1: Comparison of Targeted Allocation Parameter Gradient and Cooperative Processing Efficiency

[0038]

[0039] See Table 1, when the molar ratio Depend on Upgraded to At that time, the carrier loading density increased, proving that the binary organic acid anions constructed stable interlayer support channels, and when Increase to At that time, the load density decreased to Furthermore, the increased total phosphorus concentration in the effluent indicates that excessive dicarboxylic acid occupies too many adsorption sites, thus confirming... to The range is the preferred working window for this process; data from control group 3 indicate that, in the absence of... During charge relaxation driven by periodic switching, the load density is only that of test group 2. This verified the role of the pH pulse mechanism in overcoming mass transfer resistance; control group 4 was running Later, due to the passivation of grease, the phosphorus removal efficiency deteriorated. However, in Experiment 2, the interfacial permeability was maintained by the Fenton-like reaction induced by transition metal ions, and the effluent indicators were finally stabilized and met the standards.

[0040] Example 3: This example combines Figures 1 to 2 The process for the synergistic treatment of food waste hydrolysate with a targeted formulation of biocarbon source and LDH carrier is described, such as... Figure 1 As shown, in step S101, the primary hydrolysate produced by the anaerobic fermentation of kitchen waste is obtained through solid-liquid separation. Exogenous acetic acid or propionic acid is added according to the total volatile fatty acid concentration, and the molar ratio of binary to monobasic organic acid anions is adjusted to 0.15 to 0.35 to obtain a directionally formulated biocarbon source. In step S102, powdered LDH carrier is added to the contact conditioning tank and the directionally formulated biocarbon source is injected. The Reynolds number of the mixed liquid is controlled to be 300 to 800 by adjusting the speed of the stirring equipment to achieve full mixing and contact between the carrier and the carbon source. Then, in step S103, the effluent from the biochemical system is introduced to adjust the pH value of the mixed liquid to 6.5 to 8.5 and periodically switch it to change the hydroxyl dissociation state of the carrier layer to adjust the surface charge density. The potential gradient is used to drive the binary organic acid anions into the interior of the carrier layer. Finally, in step S104, the loaded carrier is discharged into the anoxic zone of the biochemical system. The phosphate in the anoxic zone is used to exchange ions with the organic acid anions in the interlayer. At the same time, the directionally formulated biocarbon source is released into the biochemical system, and the phosphate in the anoxic zone is adsorbed.

[0041] like Figure 2 As shown, this interactive logic involves multiple units including a pH controller, effluent from the biological system, a contact conditioning tank, LDH carrier plates, the LDH interlayer region, and binary organic acid anions. The process begins with pH adjustment initiation. The pH controller sets the switching cycle T to satisfy T=HRT / n, where n is 3 to 6. Simultaneously, effluent from the biological system is introduced, and the pH is adjusted to 6.5. During the low pH phase, charge changes occur, and the pH controller maintains a low pH environment, causing hydroxyl protonation of the LDH carrier plates. This results in an increase in surface positive charge and the generation of a potential gradient, attracting binary organic acid anions into the LDH interlayer region. Subsequently, a pH cycle switching occurs, and the pH controller adjusts the pH to 8.5. Under the influence of the high pH environment, hydroxyl deprotonation occurs in the LDH carrier plates, leading to a change in surface charge density. Afterward, a high pH phase of deep migration occurs, using the potential gradient change to drive the organic acid anions to migrate towards the center, occupying deep active sites and forming a supporting framework through dual-site anchoring. Finally, in the cycle switching completion phase, after n cycles of switching, the LDH interlayer region achieves full-domain saturation loading and hierarchical orderly distribution of active sites.

[0042] Example 4: When the inlet water temperature is consistently lower than In the deep phosphorus removal process of urban wastewater treatment plants, the increased viscosity of the wastewater leads to... The ion migration barrier between the support layers is increased, and the measured mass transfer resistance is lower than that of the previous layer. Improved working conditions The system uses online potential sensors to monitor the contact conditioning tank. Surface potential of the carrier ,set up The value switching slope is and record The time constant for the potential to switch from equilibrium to the target potential When the time constant Exceeding the hydraulic residence time of At that time, according to Step size is adjusted upwards to correct the number of loop switches. The increased switching frequency is used to offset the charge response hysteresis and maintain the diffusion flux of the directed biological carbon source to the central region of the carrier interlayer.

[0043] Use small corner X-ray scattering technology for monitoring different molar ratios Layer spacing of the download body In molar ratio for And the molar concentration of transition metal ions is Under operating conditions, the interlayer spacing From the original carrier Expand to At this time, the redox potential gradient between the anoxic and aerobic zones of the biochemical system is controlled. for The induced generation of hydroxyl radicals on the carrier surface helps to detach attached oils and extracellular polymers. The measured total phosphorus concentration in the effluent of the biochemical system decreased from [previous value]. Down to .

[0044] Example 5: Under the condition of seasonal fluctuations in food waste material, the total volatile fatty acid mass concentration of the primary hydrolysate is within... to The system utilizes the variation between these values ​​to adjust the conductivity. Correlation curves were established between the total volatile fatty acid mass concentration and the hydrolysate stock solution before deployment. Based on these curves, the correlation ratio between the exogenous dicarboxylic acid replenishment flux and the primary hydrolysate influent flow rate was determined. When the sensor detected conductivity... When the change exceeds the deviation limit, the system adjusts the dosing pump frequency to adjust the dosage of the exogenous dicarboxylic acid, and adjusts the molar ratio of dicarboxylic acid to monocarboxylic acid before the mixture enters the contact equalization tank. Controlled .

[0045] When the system is applied to wastewater treatment environments with alkalinity differences, the acid-base buffer capacity of the wastewater mixture directly affects the response frequency of the charge relaxation driving force. Alkalinity gradients under different reflux ratios were simulated in a calibration vessel, and a directionally formulated biological carbon source was injected. An online pH meter was used to record the response time required for the pH of the mixture to decrease from 8.5 to 6.5 at a constant acid dosing rate. The measured alkalinity Alk was compared with the response time. The corresponding value is stored in the controller's storage unit, and the corresponding switching slope is matched according to the real-time monitored alkalinity Alk. If the response time... Increasing the number of cycles n decreases the number of cycles while simultaneously increasing the single fluctuation period T. Under conditions of alkalinity of 450 mg / L, with the number of cycles n set to 3 and the switching slope at 0.6 / min, the measured interlayer displacement flux of the LDH carrier is... Furthermore, the total phosphorus concentration in the effluent from the biochemical system is below 0.25 mg / L.

[0046] Example 6: In the co-processing of kitchen waste with an influent total alkalinity exceeding 600 mg / L and significant fluctuations in sludge settling performance, the high alkalinity background increases the lag in pH adjustment of the mixed liquor. Before operation, the system underwent carrier physical parameter adaptation and degassing process calibration. The particle size distribution of the LDH carrier was determined based on the sludge volume index (SVI) in the anoxic zone of the biochemical system. The uniformity of the carrier distribution was maintained by controlling the settling velocity of the LDH carrier to be no less than 1.2 times that of the activated sludge flocs. In actual testing, with an SVI of 150 mL / g, the median particle size D50 was selected as... The powdered LDH carrier reduces the risk of carrier loss with residual sludge.

[0047] In the degassing process, the system removes dissolved carbon dioxide to stabilize alkalinity by adjusting the air-to-water ratio of the aeration unit. The physical parameters of the degassing equilibrium state are determined by the mixed liquor. The absolute value of the time derivative of the value is lower than The calibration process sets the aeration intensity to ensure the air-to-water ratio is within a certain range. to Perform gradient testing on intervals and extract the corresponding values. Response slope: To address judgment biases caused by sensor signal drift, the controller executes a real-time verification program based on comparing the response slope with a historical benchmark curve. When the detected slope deviation exceeds... The system automatically adjusts the operating frequency of the dosing pump to correct the replenishment ratio of dibasic organic acid ions. Under high alkalinity conditions, the air-to-water ratio is set accordingly. And match the number of loop switches for This generates a charge relaxation driving force that drives the directional migration of ions, thus stabilizing the total phosphorus concentration in the effluent of the biochemical system at a certain level. the following.

[0048] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A process for the synergistic treatment of food waste hydrolysate with a bio-carbon source and an LDH carrier, characterized in that, Includes the following steps: Step S101, directional blending step: Obtain the primary hydrolysate produced by anaerobic fermentation of kitchen waste through solid-liquid separation; add dibasic organic acids to the primary hydrolysate according to the total volatile fatty acid concentration in the primary hydrolysate; the dibasic organic acid anions include at least one of the following: succinate, malate, oxalate; adjust the molar ratio of dibasic organic acid anions to monobasic organic acid anions in the primary hydrolysate to 0.15 to 0.35 to obtain a directional blended biocarbon source; Step S102, the mixing and contacting step, involves adding powdered LDH carrier to the contact conditioning tank and injecting a directionally formulated biocarbon source into the contact conditioning tank. The Reynolds number of the mixture in the contact conditioning tank is controlled to be between 300 and 800 by adjusting the rotation speed of the stirring equipment in the contact conditioning tank. Step S103, Interlayer Exchange Enhancement Step: During the mixing and contacting step, effluent from the biochemical system is introduced into the contact conditioning tank to periodically switch the pH value of the mixed solution between 6.5 and 8.

5. The surface charge density of the LDH carrier is adjusted by changing the hydroxyl dissociation state on the surface of the LDH carrier layer. The potential gradient formed between the mixed solution and the LDH carrier layer drives the directional distribution of the dibasic organic acid anions in the biological carbon source into the interlayer interior of the LDH carrier. Step S104, the synergistic phosphorus removal step, involves discharging the loaded LDH carrier into the anoxic zone of the biochemical system. The phosphate in the anoxic zone of the biochemical system undergoes ion exchange with the organic acid anions between the LDH carrier layers. While releasing a directionally distributed biological carbon source into the anoxic zone of the biochemical system, the phosphate in the anoxic zone of the biochemical system is adsorbed.

2. The process for the directional blending of biological carbon source and LDH carrier in the hydrolysate of kitchen waste according to claim 1, characterized in that, In step S101, while adjusting the organic acid components, a polyhydroxy polyol is added to the primary hydrolysate to make the mass concentration of the polyhydroxy polyol in the biocarbon source directionally adjusted to be 50 mg / L to 150 mg / L; the polyhydroxy polyol forms a polarity regulating layer on the surface of the LDH carrier to limit the diffusion of mono-inorganic anions in the mixture into the interlayer of the LDH carrier.

3. The process for the directional blending of biocarbon source and LDH carrier in the hydrolysate of kitchen waste according to claim 1, characterized in that, In step S102, magnesium-aluminum bimetallic hydroxide is selected as the LDH carrier, and the molar ratio of Mg to Al cations in the LDH carrier is 2 to 4. The concentration of LDH carrier added in the contact conditioning tank is controlled to be 200 mg / L to 600 mg / L, and the mass ratio of biological carbon source to LDH carrier is 20:1 to 50:

1.

4. The process for the directional blending of biological carbon source and LDH carrier in the hydrolysate of kitchen waste according to claim 1, characterized in that, In step S103, the single fluctuation cycle of pH value Hydraulic residence time of the mixture in the contact conditioning tank The following relationship must be satisfied: in, It represents a single fluctuation period, with the unit being hours (h). The preset residence time of the mixture in the contact conditioning tank is expressed in hours (h). The preset number of cycle switching times, and It is an integer between 3 and 6.

5. The process for the directional blending of biocarbon source and LDH carrier in the hydrolysate of kitchen waste according to claim 1, characterized in that, Before performing the targeted formulation step, a transition metal enrichment step is also included: using a membrane separation unit to retain iron, manganese and nickel ions in the primary hydrolysate, adjusting the total molar concentration of transition metal ions in the targeted formulation of the bio-carbon source to 0.05 mmol / L to 0.2 mmol / L, so that the transition metal ions are loaded onto the surface defect sites of the LDH support along with the binary organic acid anions.

6. The process for the directional blending of biocarbon source and LDH carrier in the hydrolysate of kitchen waste according to claim 5, characterized in that, After the LDH carrier enters the biochemical system, the redox potential fluctuations generated when the biochemical system switches between anoxic and aerobic conditions are used to induce transition metal ions to generate free radicals, which then oxidize and strip the extracellular polymers deposited on the surface of the LDH carrier.

7. The process for the directional blending of biocarbon source and LDH carrier in the hydrolysate of kitchen waste according to claim 1, characterized in that, In step S102, the rotation speed of the stirring device is 40 r / min to 120 r / min.

8. The process for the directional blending of biocarbon source and LDH carrier in the hydrolysate of kitchen waste according to claim 1, characterized in that, Controlling the sludge retention time of the LDH carrier in the anoxic zone of the biochemical system The duration is 12 to 20 days; Monitor the total phosphorus concentration in the effluent from the secondary sedimentation tank of the biochemical system. If the total phosphorus concentration exceeds 0.5 mg / L, increase the initial dosage of LDH carrier in step S102 by 5% to 10%.

9. The process for the directional blending of biocarbon source and LDH carrier in the hydrolysate of kitchen waste according to claim 1, characterized in that, Before entering the anoxic zone of the biochemical system, the mixed liquor also includes a degassing step: the dissolved carbon dioxide in the mixed liquor is removed by the aeration unit, and the alkalinity of the mixed liquor is adjusted to 200 mg / L to 400 mg / L.

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