A method for collecting inert particles of food waste slurry based on a venturi particle collector

Abstract

The present application relates to the collection device of the inert particles in food waste slurry, in particular to the device and method for collecting the inert particles in food waste slurry by using the Venturi effect. The method comprises the steps of the inert particle collection device based on the Venturi effect, the pipeline flow velocity cloud chart drawing method, the inert particle concentration statistical method, etc. By the method of the flow velocity, the slurry inert concentration and the particle density of the target food waste slurry, the optimal arrangement scheme of the inert particle collector is determined. The Venturi type inert particle collection device of the present application comprises the inert particle settling device, the particle storage device and the connecting part between the devices. The present application takes the stable recovery of the inert particles in food waste slurry as the target, simulates and on-site debugs the slurry flow condition and the inert content, and adjusts the feedback according to the inert recovery condition each time, so as to obtain the stable recovery period and finally realize the sustainable and stable recovery of the inert particles in food waste slurry.

Description

Technical Field

[0001] The present invention belongs to the field of restaurant waste pretreatment equipment and relates to a method for collecting inert particles in restaurant waste slurry, in particular to a restaurant waste slurry inert particle collector controlled by a Venturi effect, as well as the fields of solid sedimentation, fluid mechanics, environmental engineering, etc. Background Art

[0002] Inert particles in catering waste refer to various inorganic or organic particles and fragments that exist in the slurry after catering waste pulping and cannot be used by subsequent anaerobic fermentation microorganisms. The pretreatment of catering waste is carried out by screening to remove large-sized impurities (>20mm) and then crushing and pulping. The remaining fine inert particles remain in the pipeline and are pumped into the anaerobic fermentation tank together with the garbage slurry. The scum floats on the top of the slurry or sinks to the bottom of the anaerobic tank, causing blockage. The presence of inert particles poses a great obstacle to the pretreatment of catering waste and the sustainability of anaerobic fermentation. At present, the separation of inerts is mainly carried out by cyclone sand removal, centrifugal impurity removal and other methods, which are costly and occupy a large area. They are not suitable for the improvement of existing processes. At the same time, there is no special technology for removing fine inert particles in the slurry.

[0003] my country generates a huge amount of catering waste every year, and inert materials account for a certain proportion of the catering waste. At present, the collection method of inert materials in the pre-treatment of catering waste is relatively simple, and the commonly used process is crushing, screening and separation. Before pulping catering waste, the original waste is first screened out impurities larger than 60mm by a large material sorter, and then screened out impurities larger than 20mm by a fine separator, mainly including small-particle debris such as bottle caps and chopsticks, and lightweight debris such as plastic and paper. Materials below 20mm are made into slurry below 8mm, and then pumped into the sand and impurity removal unit, which removes heavy materials such as shells, glass, porcelain pieces, sand and gravel, and other fine fibers in the material, and then enters the oil extraction unit.

[0004] At present, the sorting of materials in the pre-treatment process of catering waste is the main technical difficulty. There are currently two main types of catering waste sorting technologies. One is to set up only one comprehensive sorting device, and the other is to set up multi-stage sorting equipment, which basically adopts the process of crushing, screening, sand removal and impurity removal. Due to the complexity of catering waste raw materials, when a comprehensive sorting device is used, the catering waste flow must be large and the processing speed must be fast. In order to ensure that the discharge screening particle size is not very small, there are many impurities and large particles in the slurry after pulping. At the same time, equipment replacement will be very frequent, affecting normal production. Multiple grading equipment will lead to problems such as too long a pre-treatment process and increased organic matter loss.

[0005] Existing processes are unable to screen out all inerts during the pretreatment stage, and multi-stage sorting will make the inert particles finer, making them more difficult to settle. Therefore, the benefits of adding screening or settling equipment to existing processes are disproportionate to the costs. The already broken inert fine particles will cause varying degrees of wear and tear on subsequent pretreatment facilities such as three-phase centrifuges and transportation pipelines. Whether inerts promote the anaerobic fermentation of catering waste is currently unknown. However, excessive inerts can reduce the effective volume of the anaerobic tank and hinder material inlet and outlet flow. The replacement and maintenance costs of large-scale equipment are very high. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to process catering waste, especially to quickly and efficiently collect inert particles in catering waste slurry, so as to realize periodic and sustainable collection of inert particles in catering waste slurry.

[0007] In order to solve the above problems, the present invention designs a method for collecting inert particles in catering waste slurry using a Venturi-type catering waste inert particle collector, and designs a catering waste slurry inert particle collector based on the Venturi effect to realize a sustainable collection solution for catering waste slurry inert particles.

[0008] To achieve the above-mentioned object, the method for collecting slurry inert particles of the present invention comprises the following two stages:

[0009] First, the slurry flow rate and viscosity are investigated based on the process conditions at the target pretreatment project site. The initial flow rate is measured using a flowmeter, with tests conducted at the inlet and outlet of the slurry pipe section and at the observation port. A flow velocity distribution diagram for the pretreatment slurry pipe section is plotted. Viscosity is measured using a rheometer. After collecting samples, the initial concentration of inert particles is measured by drying and gravimetric methods. The measured data is used to plot a slurry flow nephogram and a particle distribution nephogram. Based on the slurry flow nephogram and velocity nephogram, an appropriate installation pipe section is selected. Once the pipe section is determined, the straight pipe length of the collector, the location of the inert discharge port, and the ratio of the front and rear pipe diameters are determined based on the initial flow rate, initial inert concentration, and density of the on-site process slurry. These are then determined through parametric scanning using device design experiments and ANSYS FLUENT fluid simulation experiments, and adjusted based on the actual inert content of the slurry.

[0010] Secondly, the collection mechanism of inert particles in catering waste slurry is realized.

[0011] Flow velocity (or current velocity) refers to the displacement of a liquid per unit time. Flow velocity distribution refers to the distribution of the direction and magnitude of the flow velocity at various points on a specific cross-section.

[0012] Currently, there are relatively few studies that measure the types of inerts in food waste and their concentrations in slurries. This method uses random sampling experiments to quantify fluid dynamics data such as the content and types of inerts in the slurry. A two-phase flow model for food waste slurry flow is developed based on previous laboratory simulations and experimental results.

[0013] Simulation process: The initial geometric model of the collector is designed based on the inlet pipe diameter, flow rate, etc. (the parameters can be randomly selected within the range). After meshing, the slurry fluid mechanics data is input into the two-phase flow simulation model as the basic simulation parameters. The slurry flow is simulated for 30 minutes and 1 hour to observe the changes in the dispersed phase concentration and the locations where inert materials can accumulate in the pipeline.

[0014] Based on the inlet diameter d0, the front-to-back diameter ratio D / d is selected within a range of 1.5-3. The throat diameter d and the settling pipe diameter D are also selected. The throat angle (preferably horizontal) and length (preferably equal to the pipe diameter) are also determined. The length of the collector pipe is determined based on the simulation results of the distance at which the slurry flow stabilizes after the Venturi effect. A parametric sweep optimization is performed for all combinations of these parameters (i.e., each parameter combination is simulated and the changes in dispersed phase concentration are observed). The parameter combination and location with the lowest dispersed phase concentration are finally determined, which is the inert discharge location.

[0015] Specifically, the present invention provides a method for collecting inert particles in restaurant waste slurry, comprising the following steps:

[0016] (1) The initial flow rate test, initial concentration of inert particles, and density test of the catering waste slurry in a specific pipe section are conducted and statistically analyzed to determine the design parameters of the collection device and the optimal layout position and operating conditions, and to estimate the amount of inert removal and the number and cycle of collector layout.

[0017] Preferably, it is necessary to first investigate the pretreatment pipe section and select the three pipe sections: the pipe section after pulping (the connecting pipe section between the pulping machine and the sand and impurity removal unit), the pipe section after sand and impurity removal (the connecting pipe section between the sand and impurity removal and the oil removal unit), and the pipe section after three-phase separation (the pipe section before entering the homogenization tank). The collector should be installed with a pipe section with a stable flow rate.

[0018] Based on the parametric sweep results, the result with the lowest inert particle concentration at the final simulation state (e.g., after 20-60 minutes of testing) is selected, and the inert removal amount is estimated by the difference between the two. The number of placers is determined by the required inert removal rate. If the initial simulation concentration is a%, the minimum particle concentration after simulation is b%, and the required concentration is c%, then the required number of placers, n, is calculated as follows:

[0019]

[0020] Just round up.

[0021] The operation cycle is to collect twice a day, that is, once every 4 hours. The cycle can be adjusted every day according to the slurry quality.

[0022] (2) Arrange the Venturi-type inert particle collector at the optimal location determined in step (1), hang the filter in the collection device, and ensure that the pipe interface is firm; conduct a preliminary sedimentation test, adjust and optimize the parameters, and put it into formal use after the test is completed.

[0023] First, the need to adjust the opening position and the diameter of the particle collection pipe can be determined based on the initial sedimentation effect. Then, the need to change the screen aperture can be determined based on the on-site inert material flushing and screening conditions. Finally, the final sedimentation cycle can be determined based on the sedimentation effect.

[0024] (3) A reasonable recovery period of the inert particles is calculated based on the concentration and density of the inert particles measured and estimated in step (1). After each test, the collection pipe is opened manually to discharge the settled inert particles through the collection pipe. The position of the collector and the settling period are adjusted according to the collection situation. The collected inert particles enter the pretreatment slag discharge system, and the slurry passing through the filter returns to the pretreatment system.

[0025] (4) Repeat step (3) until a stable inert recovery cycle is obtained, forming a streamlined collection system for inert particles in catering waste slurry, reducing the content of fine inert particles in the slurry, and entering a sustainable removal mode stage.

[0026] Preferably, when the height fluctuation of the particles collected by the inert collecting tube is less than 5 cm every day and the effect of collecting the inert particles is stable for one week, it can be considered to be stable.

[0027] Preferably, the initial flow rate determination method comprises:

[0028] The flow rate was measured using a flow meter, and the viscosity was measured using a rheometer;

[0029] Draw out the flow velocity distribution diagram of the pre-treated slurry pipe section;

[0030] After collecting the samples, the initial concentration of the inert particles is measured by drying and weight method, and the slurry flow cloud map and particle distribution cloud map are drawn based on the measured data.

[0031] It will be determined based on the on-site process slurry initial flow rate measurement, inert initial concentration, density measurement, device design experiments and ANSYS FLUENT fluid simulation tests, and adjusted according to the actual slurry inert content.

[0032] Preferably, the Venturi structure design for the target pipe section is based on existing slurry flow rate measurements and initial concentration and density data of inert particles in the slurry. A simulated parametric sweep of the Venturi tube parameters is performed to obtain the optimal combination of parameters such as settling time, diameter ratio, initial flow rate, and Venturi throat diameter. Specific device parameters and location are then selected based on the simulation results. The throat refers to the smallest diameter straight section of the Venturi tube.

[0033] Preferably, the Venturi-type catering waste slurry inert particle collector includes an inlet pipe interface, a variable-diameter Venturi tube, a straight sedimentation pipe, an observation flushing pipe, a particle collection pipe, a filter, a slurry flow pipe, a tapered pipe, and an outlet pipe interface.

[0034] Preferably, the inert particle collection device utilizes the Venturi effect to separate the inert particles from the slurry body. The inert particle collection device is mainly composed of a straight sedimentation pipe. According to simulation results, openings are set at the places where the inert particles in the straight pipe settle and accumulate, and observation flushing ports are set at the upper parts of the corresponding positions of the openings to facilitate observation of the sedimentation situation and flushing when collecting the inert particles.

[0035] Preferably, an inert particle collection device is located behind the variable-diameter Venturi tube, wherein a straight sedimentation tube is connected to the Venturi tube, an observation and flushing tube is connected to the upper end of the straight sedimentation tube, the lower end is connected to the particle collection tube, and the straight tube outlet is connected to the tapered tube and the outlet pipe interface. The three parts together constitute the inert particle collection device.

[0036] Preferably, the catering waste slurry inert particle collector comprises five parts: a straight sedimentation pipe, an observation flushing pipe, a connecting pipe, a particle collection pipe, and a slurry flow pipe. The observation flushing pipe is used to observe the deposition of inert matter and flush water during collection to facilitate the entry of all inert matter into the collection pipe. The particle collection pipe is provided with a filter and can be disassembled into two parts. The liquid phase passes through the filter and returns to the slurry pool, and the inert particles are collected and transported out.

[0037] Preferably, the filter replacement operation is performed manually by disassembling the slurry flow pipe of the catering waste slurry inert particle collector, directly taking out the particle collection pipe section, and taking out the inert matter therein together, and replacing the new collection filter, reconnecting it to the slurry flow pipe, and starting a new round of garbage collection process.

[0038] Accordingly, the present invention further provides a device for collecting inert particles in a slurry of restaurant waste, including a Venturi-type collector for inert particles in a slurry of restaurant waste; the Venturi-type collector for inert particles in a slurry of restaurant waste includes an inlet pipe interface, a variable-diameter Venturi tube, a straight settling pipe, an observation flushing pipe, a particle collection pipe, a slurry flow pipe, a tapered pipe, and an outlet pipe interface;

[0039] The inlet pipe interface, the variable diameter venturi tube, the settling straight pipe, the slurry flow pipe, the tapered pipe, and the outlet pipe interface are connected in sequence. The inner diameter of the settling straight pipe is larger than the diameters of the inlet pipe interface and the outlet pipe interface. The inner diameter of the variable diameter venturi tube is the smallest inner diameter part of the venturi-type catering waste slurry inert particle collector.

[0040] An observation flushing pipe is arranged on one side of the sedimentation straight pipe, and a particle collecting pipe is arranged on the other side of the sedimentation straight pipe corresponding to the observation flushing pipe.

[0041] Preferably, the particle collection pipe includes a connecting pipe and a filter screen. The slurry that passes through the filter screen is returned to the slurry pool, and the inert particles are collected and transported out. A connecting pipe cap is provided between the connecting pipe and the particle collection pipe. Preferably, the slurry is directly fed into the slurry pool, but the slurry can also be collected and then sent to the slurry pool.

[0042] like Figure 1 As shown, the Venturi-type catering waste slurry inert particle collector is composed of the following characteristic components: (1) inlet pipe interface; (2) variable diameter Venturi tube; (3) variable diameter straight pipe; (4) observation flushing pipe; (5) connecting pipe; (6) particle collection pipe cover; (7) particle storage pipe; (8) filter screen; (9) slurry flow pipe; (10) outlet pipe interface.

[0043] The Venturi effect, also known as the Venturi effect, occurs when a restricted flow passes through a narrowing flow path, increasing its velocity. The velocity is inversely proportional to the flow path. Bernoulli's principle states that this increase in velocity is accompanied by a decrease in fluid pressure, a phenomenon commonly known as the Venturi phenomenon. In layman's terms, this effect creates a low pressure near a high-speed flow, leading to adsorption. Pipes that exploit this effect are called Venturi tubes.

[0044] The present invention provides a Venturi-type collection device for inert particles in restaurant waste slurry. The device consists of an inlet and outlet pipe interface, a variable-diameter Venturi tube, and an inert particle collector. The inert particle collector comprises an observation flushing pipe, a straight settling pipe, and a particle collection pipe. The observation flushing pipe is used to monitor the inert deposition and flush water during collection to ensure that all inert particles enter the collection pipe. The particle collection pipe is equipped with filter holes and is removable into a connecting pipe, a particle storage pipe, and a slurry flow pipe. The slurry that passes through the filter returns to the slurry tank, while the inert particles are collected and transported out.

[0045] The optimal value of the front-to-back radius ratio and the throat length of the variable-diameter Venturi tube is determined through fluid simulation. The slurry flow is rapidly accelerated in the throat by relying on the Venturi effect. After entering the variable-diameter settling straight tube, the inert particles are separated from the main body of the slurry due to gravity and settle to the bottom of the tube.

[0046] The observation flushing pipe is connected to the top of the settling pipe. An observation port 50mm larger than the collection pipe diameter is set directly above the collection pipe to facilitate observation of the particle settling status during the cleaning of inert particles. At the same time, process water can be flushed in from above to help all inert particles enter the collection pipe.

[0047] The particle collection pipe consists of four parts: a connecting pipe, a particle storage pipe, a filter screen, and a slurry flow pipe. The particle storage pipe stores the deposited inert particles, and the filter screen can block the particles and allow the liquid slurry to pass through. A short connecting pipe similar to a tee is made at the outlet of the inert material in the sedimentation straight pipe ( Figure 1 ), that is, the sedimentation straight pipe and the connecting pipe are integrated, and the particle collection pipe is connected to the connecting pipe and is in a vertical relationship with the sedimentation straight pipe.

[0048] The restaurant waste slurry inert particle collection device of the present invention can be used for modular processing of restaurant waste slurry inert particle collection and sustainable recycling.

[0049] Preferably, an observation flushing pipe is connected above the straight sedimentation pipe, and an observation port 50 mm larger than the diameter of the collection pipe is set directly above the collection pipe to facilitate observation of the particle sedimentation state when cleaning the inert particles; or process water is flushed in from above to help all the inert particles enter the collection pipe.

[0050] Preferably, in the inert particle collection pipe, a pipe cover is provided on the connecting pipe portion. The pipe cover is closed during normal process operation. After the sedimentation period is reached, the pipe cover is manually opened and connected to the particle collection pipe with a filter. The washed inert particles are intercepted by the filter and stored in the storage pipe. The slurry and small organic particles pass through the filter and return to the pretreatment system.

[0051] The aforementioned inlet pipe interface is generally of the same diameter as the process transport pipeline so as to unify the initial flow rate setting.

[0052] The aforementioned outlet pipe interface is a variable diameter outlet, which can increase the slurry speed. After the diameter is reduced, it is the same as the original process pipe diameter. The front and rear pipe diameters remain unchanged, so the overall process can be modified without changing.

[0053] The aforementioned inert particle collection pipe is divided into two parts, and a pipe cover is provided on the connecting pipe part. The pipe cover is closed when the process is operating normally. After the sedimentation period is reached, the pipe cover is manually opened and connected to the particle storage pipe with a filter. The washed inert particles are intercepted by the filter and stored in the storage pipe. The slurry and small organic particles pass through the filter and return to the pretreatment system.

[0054] The present invention uses the Venturi effect as the power for collecting inert particles in catering waste slurry for the first time, and forms a complete modular method for collecting and sustainably recycling inert particles in catering waste slurry by using a collection device based on this effect.

[0055] Currently, no reports on methods for removing fine inert particles from slurry have been found. The method for collecting inert particles from restaurant waste slurry of the present invention has the following advantages:

[0056] By adding a certain number of Venturi-type inert particle collectors to the pretreatment pipeline, the inert particles can be collected, reducing wear on pretreatment pipelines and equipment and lowering the amount of inerts entering the anaerobic tank. This device eliminates the need for large-scale equipment in existing processes, occupies a small footprint, and is low-cost. When not needed, it can be directly replaced by a straight pipe of the same length. This modular design reduces processing costs and enables periodic and sustainable recovery of inert particles, facilitating the resource recovery of food waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, each drawing described below is for some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0058] Figure 1 This is a schematic structural diagram of the Venturi-type catering waste slurry inert particle collection device used in this method.

[0059] In the figure: 1 is the inlet pipe interface, 2 is the variable diameter venturi tube, 3 is the sedimentation straight pipe, 4 is the observation flushing pipe, 5 is the connecting pipe, 6 is the connecting pipe cover, 7 is the particle storage pipe, 8 is the filter screen, 9 is the slurry flow pipe, and 10 is the outlet pipe interface.

[0060] Figure 2 Flowchart for the implementation of this method. DETAILED DESCRIPTION

[0061] The following examples of the present application will clearly and completely describe the technical solution. Obviously, the described examples are only some preferred embodiments of the present application, not all embodiments. Based on the examples in the present application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0062] Example 1

[0063] In a certain catering waste pretreatment process section, the slurry pipeline after pulping is 1000mm wide and the flow rate ranges from 1-2m / s.

[0064] Velocity was measured in each pipe section after slurry preparation using a flowmeter. The collected samples were used to create velocity distribution contours. Inert particle samples were collected to calculate the particle density and estimate the initial inert concentration. The measured initial inert concentration was 6%, with an average particle size of approximately 4 mm. Following ANSYS FLUENT simulations and field pilot experiments, a collector geometry model was designed based on inlet pipe diameter, flow velocity, and other parameters. The slurry fluid dynamics data was used as the basic simulation parameters and input into the two-phase flow simulation model. A 0.5-hour flow simulation was performed to observe changes in the dispersed phase concentration.

[0065] Based on the inlet diameter d0, the front-to-back diameter ratio D / d is selected within a range of 1.5-3. The throat diameter d and the settling pipe diameter D are also selected. The throat angle and length are determined according to the design manual (national standard GB / T-2624). The collector pipe length is determined based on the distance the slurry reaches after the Venturi effect, as determined by simulation results. A parametric sweep optimization is performed for all combinations of these parameters, ultimately determining the parameter combination and location with the lowest dispersed phase concentration, which is the inert discharge location.

[0066] The main difficulties are:

[0067] 1. In the early stage, the fluid dynamics properties of catering waste slurry were measured, the inert particles were screened and the properties were determined, and the database required for slurry-inert simulation was established.

[0068] 2. Catering waste is a non-Newtonian fluid. During the simulation process, the model parameters of the two-phase flow model are adjusted to make the slurry flow closer to reality.

[0069] 3. Arrange all combinations of multiple parameters and simulate them one by one to finally select the parameter combination with the best effect.

[0070] After multiple tests and repeated optimization, the optimal Venturi-type collection device for inert particles in restaurant waste slurry has a 1 / 3 ratio of the Venturi tube, a 500mm throat length, a 7500mm straight settling tube length, a 1500mm diverging tube length, a 1000mm converging tube length, and a 3mm filter mesh aperture.

[0071] Example 2

[0072] A collection device was installed in the pipe section, collecting inert particles daily. The collection cycle was changed and the test was repeated for 14 days. After sedimentation, the inert concentration remained below 4%. The maximum amount collected per time was used as the required reservoir volume. The optimal collection pipe diameter, 1000 mm and 800 mm in length, was calculated, the same as the straight settling pipe. Furthermore, the observation and flushing pipe diameter was set to the same as the collection pipe diameter. The optimal cycle was to collect particles twice daily.

[0073] The above data is combined to finally determine the layout of the Venturi-type slurry inert particle collection device, and the final device is produced and fixed manually.

[0074] A collection filter is installed on the inert particle storage cylinder. After operation, collection is carried out according to the calculated optimal cycle. The filter status is manually checked and replaced in time after one month. The replacement frequency is adjusted according to the slurry incoming material situation. When the amount of inert particles is large, the collection and screen replacement cycle should be shortened appropriately. When the amount of inert particles is small, the collection and screen replacement cycle should be increased appropriately.

[0075] Repeat the above process of replacing and adjusting the filter screen until the cycle of each collection device tends to be stable. The removed filter screen can be reused after cleaning until it is worn out and completely damaged, forming a long-term and stable inert particle collection mode, alleviating the wear of the pretreatment equipment pipeline and reducing the content of inert particles in the slurry entering the anaerobic system.

[0076] The embodiments described above are merely specific implementations of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be imagined by any person skilled in the art within the technical scope disclosed in the present application without resorting to creative effort should be included within the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims in the present application.

Claims

1. A method for collecting inert particles in restaurant waste slurry, characterized in that: include: (1) By testing the initial flow rate, initial concentration and density of inert particles in the pre-treatment pipe section of the restaurant waste slurry and conducting statistical analysis, the design parameters of the collection device and the optimal layout position and operating conditions are determined, and the inert removal amount, the number of collector layouts, and the cycle are estimated; First, it is necessary to investigate the pretreatment pipe section and select the pipe section after pulping, the pipe section after sand and impurity removal, and the pipe section after three-phase separation. The collector should be installed in the pipe section with stable flow rate; Based on the results of the parametric sweep, the result with the minimum final inert particle concentration is selected, and the inert removal amount is estimated by the difference between the two. The number of placers is determined by the required inert removal rate. If the initial concentration of the simulation is a%, the minimum particle concentration after the simulation is b%, and the required concentration is c%, then the required number of placers n is calculated as follows: ， Just round it up; The operation cycle is to collect twice a day, i.e. once every 4 hours, and the cycle is adjusted every day according to the slurry quality; (2) Arrange the Venturi-type inert particle collector at the optimal location determined in step (1), hang the filter in the collection device, and ensure that the pipe interface is firm; conduct a preliminary sedimentation test, adjust and optimize the parameters; First, based on the initial sedimentation results, determine whether the opening position and the diameter of the particle collection pipe need to be adjusted. Then, based on the on-site inert material flushing and screening conditions, determine whether the screen aperture needs to be changed. Finally, determine the final sedimentation cycle based on the sedimentation results. (3) Calculate a reasonable recovery cycle of inert particles based on the concentration and density of the inert particles measured and estimated in step (1). After each test, manually open the collection pipe to discharge the settled inert particles through the collection pipe. Adjust the collector position and the settling cycle according to the collection situation. The collected inert particles enter the pretreatment slag discharge system, and the slurry passing through the filter returns to the pretreatment system. (4) Repeat step (3) until a stable inert recovery cycle is obtained, forming a streamlined collection system for inert particles in catering waste slurry, reducing the content of fine inert particles in the slurry, and entering a sustainable removal mode stage.

2. The method for collecting inert particles in restaurant waste slurry according to claim 1, characterized in that: The initial flow rate determination method comprises: The flow rate was measured using a flow meter, and the viscosity was measured using a rheometer; Draw out the flow velocity distribution diagram of the pre-treated slurry pipe section; After collecting the samples, the initial concentration of the inert particles is measured by drying and weight method, and the slurry flow cloud map and particle distribution cloud map are drawn based on the measured data.

3. The method for collecting inert particles from restaurant waste slurry according to claim 1, characterized in that: The length of the settling straight pipe and the ratio of the front and rear pipe diameters of the Venturi-type inert particle collector will be determined based on the initial flow rate of the on-site process slurry. The initial concentration and density of the inert particles will be determined through device design experiments and ANSYS FLUENT fluid simulation tests, and will be adjusted based on the actual inert content of the slurry.

4. The method for collecting inert particles from restaurant waste slurry according to claim 1, characterized in that: The design of the Venturi structure of the target pipe section is based on the existing slurry flow rate measurement and the initial concentration and density data of the slurry inert particles. The parameters of the Venturi tube are simulated and parametrically scanned to obtain the optimal combination of sedimentation time, diameter ratio, initial flow rate, and throat diameter parameters. The specific device parameters and setting location are selected according to the simulation results.

5. The method for collecting inert particles from restaurant waste slurry according to claim 1, characterized in that: The Venturi-type catering waste slurry inert particle collector comprises an inlet pipe interface, a variable-diameter Venturi tube, a straight sedimentation pipe, an observation flushing pipe, a particle collection pipe, a filter screen, a slurry flow pipe, a tapered pipe, and an outlet pipe interface.

6. The method for collecting inert particles from restaurant waste slurry according to claim 5, characterized in that: The inert particle collector utilizes the Venturi effect to separate the inert particles from the main body of the slurry. The inert particle collector is mainly composed of a straight settling pipe. According to simulation results, openings are set at the locations where the inert particles settle and accumulate in the straight pipe. An observation flushing port is set above the corresponding position of the opening to facilitate observation of the sedimentation situation and flushing when collecting the inert particles.

7. The method for collecting inert particles from restaurant waste slurry according to claim 5, characterized in that: The variable diameter venturi tube is connected to the inert particle collector, wherein the sedimentation straight pipe is directly connected to the variable diameter venturi tube, the observation flushing pipe is connected to the upper end of the sedimentation straight pipe, the lower end is connected to the particle collection pipe, and the straight pipe outlet is connected to the tapered pipe and the outlet pipe interface. The three parts together constitute the inert particle collection device.

8. The method for collecting inert particles from restaurant waste slurry according to claim 5, characterized in that: The catering waste slurry inert particle collector comprises five parts: a straight sedimentation pipe, an observation flushing pipe, a connecting pipe, a particle collection pipe, and a slurry flow pipe. The observation flushing pipe is used to observe the sedimentation of the inert matter and flush water during collection to facilitate the entry of all the inert matter into the collection pipe. The particle collection pipe is provided with a filter and can be disassembled into two parts. The liquid phase passes through the filter and returns to the slurry pool, while the inert particles are collected and transported out.

9. A device for collecting inert particles from restaurant waste slurry according to any one of claims 1 to 8, characterized in that: It includes a Venturi-type catering waste slurry inert particle collector; the Venturi-type catering waste slurry inert particle collector includes an inlet pipe interface, a variable diameter Venturi tube, a settling straight pipe, an observation flushing pipe, a particle collection pipe, a slurry flow pipe, a tapered pipe, and an outlet pipe interface; The inlet pipe interface, the variable diameter venturi tube, the settling straight pipe, the slurry flow pipe, the tapered pipe, and the outlet pipe interface are connected in sequence. The inner diameter of the settling straight pipe is larger than the diameters of the inlet pipe interface and the outlet pipe interface. The inner diameter of the variable diameter venturi tube is the smallest inner diameter part of the venturi-type catering waste slurry inert particle collector. An observation flushing pipe is arranged on one side of the sedimentation straight pipe, and a particle collecting pipe is arranged on the other side of the sedimentation straight pipe corresponding to the observation flushing pipe.

10. The device for collecting inert particles in restaurant waste slurry according to claim 9, characterized in that: The particle collection pipe is provided with filter holes and can be disassembled into three parts: a connecting pipe, a particle storage pipe and a slurry flow pipe. The slurry passing through the filter returns to the slurry pool, and the inert particles are collected and transported out; a connecting pipe cover is provided between the connecting pipe and the particle collection pipe.

11. Application of the restaurant waste slurry inert particle collection device according to claim 9, characterized in that: The catering waste slurry inert particle collection device is used for modular processing of catering waste slurry inert particle collection or sustainable recycling.

12. Application of the restaurant waste slurry inert particle collection device according to claim 11, characterized in that: The observation flushing pipe is connected above the sedimentation straight pipe. An observation port 50 mm larger than the diameter of the collection pipe is set directly above the collection pipe to facilitate observation of the particle sedimentation status when cleaning the inert particles; or process water can be flushed in from above to help all the inert particles enter the collection pipe.

13. Application of the restaurant waste slurry inert particle collection device according to claim 11, characterized in that: In the inert particle collection pipe, a pipe cover is provided on the connecting pipe part. The pipe cover is closed during normal process operation. After the sedimentation period is reached, the pipe cover is manually opened and connected to the particle collection pipe with a filter. The washed inert particles are intercepted by the filter and stored in the storage pipe. The slurry and small organic particles pass through the filter and return to the pretreatment system.

14. Application of the restaurant waste slurry inert particle collection device according to claim 11, characterized in that: The application includes collecting inert particles from a restaurant waste slurry, comprising the following steps: Calculate the width of the slurry pipeline after slurrying, the slurry flow rate range, and the inert particle density of the catering waste slurry to be processed; A parameter combination is obtained using a two-phase flow simulation model, wherein the parameters include one or more of the following: a variable diameter ratio of the variable diameter venturi tube, a throat length, a settling straight tube length, a gradually expanding tube length, a gradually converging tube length, and a filter mesh aperture; The parameter combination with the lowest dispersed phase concentration and the position of the Venturi-type restaurant waste slurry inert particle collector were obtained.

15. Application of the restaurant waste slurry inert particle collection device according to claim 11, characterized in that: The application comprises the following steps: A Venturi-type catering waste slurry inert particle collector is connected to the pipe section of the catering waste pretreatment equipment to collect inert particles every day. The maximum amount collected each time is used as the volume of the required storage tank, and the diameter and length of the particle collection pipe and the sedimentation straight pipe, as well as the collection cycle, are calculated.

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