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CN-122007331-A - Anti-caking control method and system for thermal regeneration of foundry waste sand

CN122007331ACN 122007331 ACN122007331 ACN 122007331ACN-122007331-A

Abstract

The invention discloses an anti-caking control method and system for thermal regeneration of foundry waste sand, which relate to the technical field of casting, and realize accurate control of an anti-caking process by constructing a set of closed-loop control system integrating real-time feedback and multi-technology cooperation, effectively inhibit sand fusion bonding caused by local overheating in the regeneration process, the invention organically combines a plurality of technical means such as multi-stage temperature gradient control, inert gas flow fluidization, bio-based anti-caking agent addition, infrared real-time monitoring and the like, and enhances each technical link mutually by linkage control driven by data flow, thereby generating a synergistic gain effect. The targeted accurate intervention avoids global excessive treatment of the traditional method, reduces consumption of heat energy and an anti-caking agent, and improves resource utilization efficiency.

Inventors

  • REN QIFANG
  • DING YI
  • MA RUI
  • JIN ZHEN

Assignees

  • 安徽建筑大学

Dates

Publication Date
20260512
Application Date
20260413

Claims (10)

  1. 1. The anti-caking control method for thermal regeneration of the foundry waste sand is characterized by comprising the following steps of: step 1, obtaining casting waste sand, and preprocessing the casting waste sand to generate preprocessed waste sand; step 2, placing the pretreated waste sand in thermal regeneration equipment, and heating the pretreated waste sand by using a multi-stage temperature gradient control curve to generate heated waste sand; step 3, introducing inert gas flow into the heated waste sand and synchronously adding a bio-based anti-caking agent to generate fluidization treatment waste sand; step 4, monitoring the temperature of the fluidized waste sand in real time to generate temperature distribution data; Step 5, analyzing whether local hot spots exist or not based on the temperature distribution data, and generating dynamic adjustment parameters for regulating and controlling the flow of inert gas and the addition amount of the bio-based anti-caking agent; step 6, controlling the treatment process of the thermal regeneration equipment by using the dynamic adjustment parameters until the waste sand after fluidization treatment is converted into regenerated sand; And 7, cooling the reclaimed sand to obtain the final reclaimed sand.
  2. 2. The method for controlling agglomeration prevention for thermal reclamation of foundry waste sand according to claim 1, wherein in step 1, the pretreatment of foundry waste sand to produce pretreated waste sand comprises: step 1.1, crushing casting waste sand to generate crushed waste sand; and 1.2, carrying out magnetic separation and screening impurity removal operation on the crushed waste sand, and separating ferromagnetic impurities, non-sandy impurities and unqualified particle size particles to generate pretreated waste sand.
  3. 3. The method of claim 1, wherein in step 2, the heating of the pretreated waste sand using a multi-stage temperature gradient control curve comprises: Step 2.1, carrying out the first-stage retarded temperature rising treatment on the pretreated waste sand, wherein the heating rate is Generating preliminary heating waste sand; step 2.2, performing a second stage of rapid heating treatment on the preliminary heated waste sand, wherein the heating rate is Generating intermediate heating waste sand; And 2.3, performing heat preservation treatment of the intermediate heated waste sand in a third stage to generate the heated waste sand.
  4. 4. The method according to claim 1, wherein in step 3, the step of introducing an inert gas stream into the heated sand and adding a bio-based anti-caking agent simultaneously comprises: Step 3.1, introducing inert gas flow into the heated waste sand to form a fluidization state, and generating waste sand covered by the gas flow; and 3.2, adding a bio-based anti-caking agent into the waste sand covered by the air flow, and uniformly dispersing the bio-based anti-caking agent by using a fluidization state to generate fluidization treatment waste sand.
  5. 5. The method according to claim 1, wherein in step 4, the monitoring of the temperature of the fluidized waste sand in real time comprises: Step 4.1, scanning the surface of the waste sand subjected to fluidization treatment through an infrared monitoring device to obtain original temperature data; And 4.2, processing and analyzing the original temperature data to generate temperature distribution data comprising the local hot spot positions and intensities.
  6. 6. The anti-caking control method for thermal reclamation of foundry waste sand according to claim 1, wherein the specific contents of the step 5 include: step 5.1, the local hot spot intensity in the temperature distribution data is highest And temperature threshold characterizing caking risk Comparing to generate a temperature deviation signal containing not only the deviation value, namely Also comprises the position coordinates of the highest temperature point in the sand bed Thereby forming a composite signal containing intensity and position information; Step 5.2, calculating the increment of the flow of the inert gas and the increment of the adding rate of the bio-based anti-caking agent according to the intensity of the temperature deviation signal and the local hot spot position, and generating dynamic adjustment parameters; an increase in the flow of the inert gas And an increment in the rate of addition of the bio-based anti-caking agent The calculation is performed by the following proportional control relations, And Wherein And The flow and the addition proportional gain coefficients are respectively preset and used for adjusting the intensity of the control response.
  7. 7. The method according to claim 1, wherein in step 6, the process of controlling the thermal regeneration equipment by using the dynamic adjustment parameters comprises: Step 6.1, adjusting the flow rate of inert gas flow and the adding rate of the bio-based anti-caking agent according to the dynamic adjustment parameters to generate an optimized treatment environment; And 6.2, continuously treating the waste sand subjected to fluidization treatment in an optimized treatment environment until the temperature distribution data are restored to a uniform state, and generating regenerated sand.
  8. 8. The method for controlling anti-caking for thermal reclamation of foundry waste sand according to claim 1, wherein in step 7, the cooling treatment of the reclaimed sand comprises: step 7.1, transferring the reclaimed sand from the thermal reclamation equipment to a cooling device to generate cooled reclaimed sand; and 7.2, forcibly cooling the cooled reclaimed sand until the temperature of the reclaimed sand is reduced to a range allowing safe treatment, and generating final reclaimed sand.
  9. 9. The anti-caking control method for thermal regeneration of foundry waste sand according to claim 4, wherein the bio-based anti-caking agent is formed by compounding degradable starch and natural silicate, and the addition amount of the bio-based anti-caking agent and the flow of inert gas flow are linked through the dynamic adjustment parameters so as to realize a synergistic anti-caking effect of physical dispersion and chemical isolation.
  10. 10. A system for performing the anti-caking control method for thermal reclamation of foundry waste sand according to any one of claims 1 to 9, comprising: The pretreatment module is used for treating the foundry waste sand to generate pretreated waste sand; the thermal regeneration module is connected with the pretreatment module and comprises a temperature control unit, an airflow adding unit and an infrared monitoring unit, and is used for converting pretreated waste sand into regenerated sand; the cooling module is connected with the thermal regeneration module and is used for converting the regenerated sand into final regenerated sand; the infrared monitoring unit is configured to generate temperature distribution data, and the temperature distribution data is used for controlling the flow of the inert gas flow in the gas flow adding unit and the adding amount of the bio-based anti-caking agent in a linkage manner.

Description

Anti-caking control method and system for thermal regeneration of foundry waste sand Technical Field The invention relates to the technical field of casting, in particular to an anti-caking control method and system for thermal regeneration of casting waste sand. Background Casting is one of the basic processes of the modern industry, in which the sand used for casting moulds, i.e. foundry sand, is the main consumable in the production process. In order to reduce the production cost and the emission of industrial solid waste, the recycling and regeneration of the used foundry waste sand becomes an important link of the foundry industry. The thermal regeneration is a regeneration technology with wide application and obvious effect, and the basic principle is that the organic matters such as the binder, the coating and the like remained on the surfaces of the waste sand particles are removed through high-temperature roasting, so that the service performance of the waste sand particles is recovered. At present, in the practice of thermal regeneration of foundry waste sand, commonly adopted technical means comprise mechanical stirring, air flow disturbance, chemical anti-caking agent addition and the like. For example, in a regeneration apparatus such as a rotary kiln or a fluidized bed, the sand particles are forced to remain in motion by mechanical movement of the apparatus or by the passage of gas to reduce static contact between the sand particles. Meanwhile, a certain amount of calcium carbonate powder or other inorganic salt is mixed into the waste sand before or during heating to serve as an anti-caking agent so as to raise the melting temperature of the low-melting eutectic in the waste sand system. However, the prior art approaches have significant drawbacks. Although the simple mechanical or air flow disturbance can play a certain physical dispersion role, the energy consumption is high, equipment abrasion is easy to cause, and the inhibition effect is limited for the problem of fusion bonding of the sand surface caused by local overhigh temperature. The chemical anti-caking agent is added unevenly, so that the subsequent use performance of the reclaimed sand is affected, and the environmental pollution is possibly caused. In addition, most of the methods are open-loop control, lack of real-time sensing and feedback adjustment of temperature change of the sand bed in the regeneration process, and cannot treat local areas where caking is about to occur in a targeted manner, so that the overall anti-caking effect is reduced. Disclosure of Invention The invention aims to provide an anti-caking control method and system for thermal regeneration of foundry waste sand, which can realize accurate inhibition of caking phenomenon, improve the quality of regenerated sand and the operation efficiency of the system and solve the problems in the background technology by using a real-time temperature monitoring feedback and multi-technology cooperative regulation and control method. In order to solve the technical problems, the invention adopts the following technical scheme that the first aspect of the invention provides an anti-caking control method for thermal regeneration of foundry waste sand, which comprises the following steps of step 1, obtaining foundry waste sand, and preprocessing the foundry waste sand to generate preprocessed waste sand. And 2, placing the pretreated waste sand in thermal regeneration equipment, and heating the pretreated waste sand by using a multi-stage temperature gradient control curve to generate heated waste sand. And 3, introducing inert gas flow into the heated waste sand and synchronously adding a bio-based anti-caking agent to generate fluidization treatment waste sand. And 4, monitoring the temperature of the fluidized waste sand in real time to generate temperature distribution data. And 5, analyzing whether local hot spots exist or not based on the temperature distribution data, and generating dynamic adjustment parameters for regulating and controlling the flow of the inert gas flow and the addition amount of the bio-based anti-caking agent. And 6, controlling the treatment process of the thermal regeneration equipment by using the dynamic adjustment parameters until the waste sand after fluidization treatment is converted into regenerated sand. And 7, cooling the reclaimed sand to obtain the final reclaimed sand. In a second aspect, the invention provides a system for performing the anti-caking control method for thermal reclamation of foundry waste sand according to the invention, comprising a pretreatment module for treating foundry waste sand to produce pretreated waste sand. The thermal regeneration module is connected with the pretreatment module and comprises a temperature control unit, an airflow adding unit and an infrared monitoring unit, and is used for converting pretreated waste sand into regenerated sand. And the cooling module is connected with the thermal