Intelligent control system for sludge drying inert gas based on oxygen concentration feedback

Abstract

The present application relates to the technical field of sludge drying explosion prevention control, and particularly relates to a sludge drying inert gas intelligent regulation and control system based on oxygen concentration feedback, which comprises a parameter monitoring unit that collects real-time oxygen content data and real-time sludge particle temperature data of the internal space of a vertical drying and granulating device, and integrates the data into feedback signals transmitted to a control unit. The control unit receives and analyzes the feedback signals, generates control instructions according to the analyzed real-time oxygen content data and real-time sludge particle temperature data, and sends the control instructions to an executing mechanism. The executing mechanism receives the control instructions, adjusts the inert gas flow into the internal space according to the control instructions. When the monitoring data is greater than a preset safety threshold, the control unit generates a control instruction to increase the opening degree of an air inlet adjusting valve, and realizes closed-loop regulation by increasing the inert gas flow, overcomes the slow response defect of the fixed flow air inlet mode in the prior art, and eliminates the dust explosion risk in the internal space.

Description

Technical Field

[0001] This invention relates to the field of explosion-proof control technology for sludge drying, and in particular to an intelligent control system for inert gas in sludge drying based on oxygen concentration feedback. Background Technology

[0002] Municipal and industrial sludge typically have extremely high moisture content, leading to sludge treatment processes often including a heating and drying step. The heating and drying of sludge, transforming it into granular form, generates a large amount of dust. This dust, when mixed with oxygen inside the drying equipment, can easily cause an explosion. To reduce safety risks, current technologies typically introduce inert gas into the drying equipment to lower the oxygen concentration inside.

[0003] Existing gas control methods have significant technical flaws. The control logic typically uses a fixed inert gas flow rate and cannot obtain real-time oxygen concentration monitoring data inside the drying equipment. Since fluctuations in the sludge feed rate cause dynamic changes in the oxygen concentration inside the drying equipment, the fixed flow rate method completely deviates from the actual oxygen concentration feedback loop, preventing the control system from adjusting the intake valve action based on real-time monitoring data.

[0004] When the oxygen concentration inside the drying equipment rises, the fixed flow of inert gas cannot dilute the oxygen in time, and the control logic responds extremely slowly to sudden high oxygen levels. This severe lag in regulation increases the probability of the drying equipment reaching its dust explosion limit, significantly increasing the risk of a dust explosion. Conversely, when the oxygen concentration inside the drying equipment is low, the control system continues to supply large amounts of inert gas, leading to excessive energy consumption and a sharp increase in operating costs. There is an urgent need to develop a new intelligent inert gas control system that establishes precise closed-loop control logic based on oxygen concentration feedback data, completely eliminating the technical pain point of lag in regulation and fundamentally avoiding the danger of dust explosions. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an intelligent control system for inert gas in sludge drying based on oxygen concentration feedback. This invention solves the technical problem that the dynamic fluctuations in oxygen concentration inside the sludge dryer make it difficult to match the inert gas flow rate in real time, resulting in a lag in system gas regulation and an increased risk of dust explosion.

[0006] To solve the above-mentioned technical problems, the specific contents of the present invention are as follows: The present invention provides an intelligent control system for inert gas in sludge drying based on oxygen concentration feedback, including a parameter monitoring unit configured in the vertical drying and granulation equipment. The vertical drying and granulation equipment has an internal space. The parameter monitoring unit collects real-time oxygen content data and real-time sludge particle temperature data of the internal space, integrates the real-time oxygen content data and real-time sludge particle temperature data into a feedback signal, and transmits the feedback signal to the control unit. The control unit is communicatively connected to the parameter monitoring unit. The control unit receives the feedback signal, parses the real-time oxygen content data and the real-time sludge particle temperature data in the feedback signal, generates control commands based on the parsed real-time oxygen content data and real-time sludge particle temperature data, and sends the control commands to the actuator. An actuator is communicatively connected to the control unit and communicates with the internal space. The actuator receives the control command and adjusts the flow rate of inert gas entering the internal space according to the control command.

[0007] Furthermore, in the intelligent control system for inert gas in sludge drying based on oxygen concentration feedback described in this invention, the parameter monitoring unit includes an oxygen acquisition module installed in the internal space. The oxygen acquisition module acquires the real-time oxygen content data of the internal space, and the real-time oxygen content data is the basic data for integrating the feedback signal.

[0008] Furthermore, in the intelligent control system for inert gas in sludge drying based on oxygen concentration feedback described in this invention, the parameter monitoring unit further includes a temperature acquisition module. The temperature acquisition module is installed in the internal space and acquires the real-time sludge particle temperature data in the internal space. The real-time sludge particle temperature data is the basic data for integrating the feedback signal.

[0009] Furthermore, in the intelligent control system for inert gas in sludge drying based on oxygen concentration feedback described in this invention, the control unit includes a signal receiving module. The signal receiving module is communicatively connected to the parameter monitoring unit. The signal receiving module receives the feedback signal transmitted by the parameter monitoring unit and parses the feedback signal to obtain the real-time oxygen content data and the real-time sludge particle temperature data.

[0010] Furthermore, in the intelligent control system for inert gas in sludge drying based on oxygen concentration feedback described in this invention, the control unit further includes an instruction generation module. The instruction generation module is communicatively connected to the signal receiving module. The instruction generation module acquires the parsed real-time oxygen content data and the real-time sludge particle temperature data, compares the acquired real-time oxygen content data and the real-time sludge particle temperature data with a preset safety threshold, and generates a control instruction for adjusting the corresponding inert gas flow rate based on the comparison result.

[0011] Furthermore, in the sludge drying inert gas intelligent control system based on oxygen concentration feedback described in this invention, the actuator includes an air inlet regulating valve. The vertical drying granulation equipment is provided with an air inlet, and the air inlet regulating valve is installed at the air inlet. The air inlet regulating valve is communicatively connected to the instruction generation module. The air inlet regulating valve receives the control instruction and adjusts the valve opening according to the inert gas flow rate adjustment amount indicated by the control instruction.

[0012] Furthermore, in the sludge drying inert gas intelligent control system based on oxygen concentration feedback described in this invention, the preset safety threshold includes a first threshold. When the instruction generation module determines that the real-time oxygen content data obtained is greater than the first threshold, the instruction generation module generates a control instruction to increase the valve opening of the air intake regulating valve, thereby increasing the flow rate of the inert gas introduced into the internal space through the air intake regulating valve, so that the real-time oxygen content data of the internal space drops below the first threshold, where the first threshold is 3%.

[0013] Furthermore, in the intelligent control system for inert gas in sludge drying based on oxygen concentration feedback described in this invention, the preset safety threshold includes a second threshold. When the instruction generation module determines that the acquired real-time sludge particle temperature data is greater than or equal to the second threshold, the instruction generation module generates a control instruction to increase the valve opening of the air intake regulating valve, thereby increasing the flow rate of the inert gas introduced into the internal space through the air intake regulating valve, so that the real-time sludge particle temperature data in the internal space drops below the second threshold, where the second threshold is 90°C.

[0014] Furthermore, the intelligent control system for inert gas in sludge drying based on oxygen concentration feedback described in this invention also includes an inert gas source. The air inlet regulating valve is provided with an air inlet end, and the inert gas source is connected to the air inlet end through an air supply pipeline. The inert gas source stores inert gas. When the air inlet regulating valve is open, the inert gas flows along the air supply pipeline through the air inlet regulating valve into the internal space.

[0015] Furthermore, in the sludge drying inert gas intelligent control system based on oxygen concentration feedback described in this invention, the vertical drying granulation equipment is provided with a discharge port, the discharge port outputs finished sludge particles, and the particle size of the finished sludge particles is greater than or equal to 3 mm and less than or equal to 5 mm.

[0016] Beneficial effects of this invention: The present invention provides an intelligent inert gas control system for sludge drying based on oxygen concentration feedback. The system utilizes a parameter monitoring unit, a control unit, and an actuator to construct a closed-loop control logic. During operation, the parameter monitoring unit collects real-time oxygen content data and real-time sludge particle temperature data from the internal space of the vertical drying and granulation equipment, and transmits the integrated feedback signal to the control unit. Subsequently, the control unit compares the parsed real-time oxygen content data and real-time sludge particle temperature data with preset safety thresholds, and generates control commands including corresponding inert gas flow rate adjustments based on the comparison results. Upon receiving the control commands, the actuator dynamically adjusts the inert gas flow rate entering the internal space of the vertical drying and granulation equipment.

[0017] The data interaction and action execution between the various devices in this invention overcome the technical defects of existing control logic that uses a fixed inert gas flow rate and is detached from the feedback loop of actual oxygen concentration. Simultaneously, the dynamic matching of data comparison and valve adjustment eliminates the problems of slow response to sudden high oxygen conditions and severe lag in adjustment actions faced by existing technologies. When the real-time oxygen content data or real-time sludge particle temperature data in the internal space of the vertical drying and granulation equipment rises, the actuator increases the inert gas flow rate according to the control command. The increased inert gas flow rate dilutes the oxygen in the internal space of the vertical drying and granulation equipment and removes the accumulated heat.

[0018] The dilution and cooling mechanism of this invention ensures that the real-time oxygen content and sludge particle temperature data within the vertical drying and granulation equipment fall below preset safety thresholds, fundamentally avoiding the risk of dust explosions during operation. Furthermore, the closed-loop mode, which dynamically adjusts based on feedback data, prevents the energy consumption and increased operating costs caused by continuously introducing large amounts of inert gas into the system under low-oxygen conditions. Attached Figure Description

[0019] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on the accompanying drawings without creative effort.

[0020] Figure 1 This is a system architecture diagram of the intelligent control system for inert gas in sludge drying based on oxygen concentration feedback, as described in this invention. Detailed Implementation

[0021] To make the technical solution of the present invention clearer, the present invention will be clearly and completely described below with reference to specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] The present invention provides an intelligent control system for inert gas in sludge drying based on oxygen concentration feedback, including a parameter monitoring unit configured in the vertical drying and granulation equipment. The vertical drying and granulation equipment has an internal space. The parameter monitoring unit collects real-time oxygen content data and real-time sludge particle temperature data of the internal space, integrates the real-time oxygen content data and real-time sludge particle temperature data into a feedback signal, and transmits the feedback signal to the control unit. The control unit is communicatively connected to the parameter monitoring unit. The control unit receives the feedback signal, parses the real-time oxygen content data and the real-time sludge particle temperature data in the feedback signal, generates control commands based on the parsed real-time oxygen content data and real-time sludge particle temperature data, and sends the control commands to the actuator. An actuator is communicatively connected to the control unit and communicates with the internal space. The actuator receives the control command and adjusts the flow rate of inert gas entering the internal space according to the control command.

[0023] The system will be described in detail below with reference to an embodiment. The system is applied to a vertical drying and granulation equipment with an internal space, an air inlet, and a material outlet, and the system mainly consists of a parameter monitoring unit, a control unit, and an actuator.

[0024] Regarding the structure of the parameter monitoring unit, the parameter monitoring unit configured in the vertical drying granulation equipment specifically includes an oxygen acquisition module and a temperature acquisition module, both of which are installed in the internal space of the vertical drying granulation equipment.

[0025] The control unit that establishes a signal connection with the parameter monitoring unit includes a signal receiving module and an instruction generation module. The signal receiving module is communicatively connected to the parameter monitoring unit, and the instruction generation module is communicatively connected to the signal receiving module.

[0026] The actuator that connects to the internal space of the vertical drying granulation equipment specifically includes an air intake regulating valve. The air intake regulating valve is installed at the air inlet, and the air intake end of the air intake regulating valve is connected to the inert gas source equipped in the system through the air supply pipeline. At the same time, the air intake regulating valve establishes a signal connection with the command generation module.

[0027] During system operation, the oxygen acquisition module collects real-time oxygen content data of the internal space of the vertical drying and granulation equipment, while the temperature acquisition module collects real-time sludge particle temperature data of the internal space of the vertical drying and granulation equipment.

[0028] After obtaining the above sampling data, the parameter monitoring unit integrates the real-time oxygen content data and the real-time sludge particle temperature data into a feedback signal and transmits the feedback signal to the control unit.

[0029] Upon receiving the feedback signal, the signal receiving module in the control unit analyzes the feedback signal, separates the real-time oxygen content data and the real-time sludge particle temperature data, and transmits the analyzed real-time oxygen content data and the real-time sludge particle temperature data to the instruction generation module.

[0030] During the logic comparison, the instruction generation module acquires the real-time oxygen content data and the real-time sludge particle temperature data, and compares the acquired data with the preset safety thresholds in the instruction generation module; the preset safety thresholds specifically include a first threshold of 3% and a second threshold of 90℃.

[0031] For monitoring oxygen content, the instruction generation module compares the acquired real-time oxygen content data with the first threshold. Once it is determined that the acquired real-time oxygen content data is greater than the first threshold, the instruction generation module immediately generates a control instruction including the corresponding inert gas flow rate adjustment.

[0032] Regarding the monitoring of temperature data, the instruction generation module compares the acquired real-time sludge particle temperature data with the second threshold. If it is determined that the acquired real-time sludge particle temperature data is greater than or equal to the second threshold, the instruction generation module also generates a control instruction including the corresponding inert gas flow rate adjustment.

[0033] After the data comparison is completed, the instruction generation module transmits the control instruction to the intake regulating valve in the actuator.

[0034] During the execution phase, the intake regulating valve receives the control command and extracts the corresponding inert gas flow rate adjustment indicated in the control command; simultaneously, the inert gas output from the inert gas source flows along the gas supply pipeline, passes through the intake end, and enters the intake regulating valve.

[0035] When adjusting the air intake opening, the air intake regulating valve increases its opening according to the corresponding inert gas flow rate regulation amount, thereby increasing the inert gas flow rate into the internal space of the vertical drying granulation equipment.

[0036] As the ventilation rate increases, the increased inert gas flow rate dilutes the gas in the internal space of the vertical drying granulation equipment, causing the real-time oxygen content data in the internal space of the vertical drying granulation equipment to drop below the first threshold. At the same time, the increased inert gas flow rate lowers the temperature in the internal space of the vertical drying granulation equipment, causing the real-time sludge particle temperature data in the internal space of the vertical drying granulation equipment to drop below the second threshold.

[0037] The final control effect is that, under the control environment constructed by the system, the vertical drying and granulation equipment maintains a stable operating state, and the discharge port of the vertical drying and granulation equipment continuously outputs finished sludge particles with a particle size greater than or equal to 3 mm and less than or equal to 5 mm. Since the real-time oxygen content data is consistently below 3% and the real-time sludge particle temperature data is consistently below 90℃, the dust explosion conditions within the internal space of the vertical drying and granulation equipment cannot be met, thus eliminating the risk of dust explosion.

[0038] This paper describes a specific implementation example using the application scenario of sludge drying and granulation in municipal wastewater treatment plants. The initial moisture content of municipal sludge output from these plants is typically as high as 80%, necessitating a continuous flow of sludge into a vertical drying and granulation equipment for dewatering and granulation. Simultaneously, the vertical drying and granulation equipment is equipped with a heat transfer oil heating system, allowing the heat transfer oil, set at 250°C, to circulate within the various layers of discs inside the equipment.

[0039] The oxygen acquisition module in the parameter monitoring unit specifically uses a zirconia oxygen concentration sensor, and the temperature acquisition module specifically uses a PT100 armored platinum resistance thermometer. Both the zirconia oxygen concentration sensor and the PT100 armored platinum resistance thermometer are installed above the discs in the internal space of the vertical drying and granulation equipment. Furthermore, the control unit specifically uses a PLC programmable logic controller, the air intake regulating valve in the actuator is a pneumatic diaphragm regulating valve, and the inert gas source is a high-pressure industrial pure nitrogen storage tank.

[0040] When in continuous feeding mode, the amount of municipal sludge fed often fluctuates abruptly. Sudden changes in the amount of feed will cause dust and water vapor to be generated in the internal space of the vertical drying and granulation equipment, which in turn will cause dynamic fluctuations in the oxygen content and sludge particle temperature in the internal space of the vertical drying and granulation equipment.

[0041] During operation, the zirconia oxygen concentration sensor continuously collects real-time oxygen content data of the internal space of the vertical drying and granulation equipment at a frequency of 10 times per second, while the PT100 armored platinum resistance thermometer simultaneously collects real-time sludge particle temperature data of the internal space of the vertical drying and granulation equipment. Subsequently, the parameter monitoring unit converts the real-time oxygen content data and the real-time sludge particle temperature data into standard analog quantities of 4 to 20 mA as feedback signals, and transmits the feedback signals to the PLC programmable logic controller.

[0042] The signal receiving module in the PLC programmable logic controller receives and parses the feedback signal so that it can separate the real-time oxygen content data and the real-time sludge particle temperature data.

[0043] When a high-oxygen state occurs in the internal space of the vertical drying granulation equipment, for example, when the real-time oxygen content data obtained from analysis climbs to 3.8%, the instruction generation module compares the value of 3.8% with the preset first threshold of 3%. If the comparison result shows that the real-time data exceeds the first threshold, the instruction generation module generates a control instruction including the corresponding inert gas flow rate adjustment, and sends the control instruction to the pneumatic diaphragm regulating valve through an electrical signal.

[0044] After receiving the control command, the pneumatic diaphragm regulating valve increases the valve opening from the original setting of 20% to 60%, thereby increasing the nitrogen flow rate output from the high-pressure industrial pure nitrogen storage tank. The pure nitrogen flows into the internal space of the vertical drying granulation equipment, diluting and reducing the real-time oxygen content data of the internal space of the vertical drying granulation equipment to 2.5% within 2 seconds. Through the combination of closed-loop feedback and the action of increasing the flow rate, the lag defect of the regulation action in the fixed flow rate air intake method is eliminated.

[0045] Regarding temperature control, when uneven heating of local sludge causes the real-time sludge particle temperature data obtained from analysis to reach 95℃, the instruction generation module compares the 95℃ value with the second threshold of 90℃. The comparison result shows that the real-time data exceeds the second threshold. The instruction generation module outputs a control instruction to increase the valve opening to the pneumatic diaphragm regulating valve. By increasing the flow rate of nitrogen gas, the heat accumulated in the internal space of the vertical drying granulation equipment is removed, and the real-time sludge particle temperature data in the internal space of the vertical drying granulation equipment is reduced to 85℃.

[0046] The system's coordinated operation with the PLC programmable logic controller and pneumatic diaphragm regulating valve eliminates environmental safety hazards caused by fluctuations in sludge feed volume. The vertical drying and granulation equipment operates stably and continuously in an explosion-proof airflow environment, and continuously outputs finished sludge particles with a particle size distribution between 3 mm and 5 mm through the discharge port of the vertical drying and granulation equipment.

Claims

1. An intelligent control system for inert gas in sludge drying based on oxygen concentration feedback, characterized in that, The device includes a parameter monitoring unit configured in the vertical drying and granulation equipment. The vertical drying and granulation equipment has an internal space. The parameter monitoring unit collects real-time oxygen content data and real-time sludge particle temperature data of the internal space, integrates the real-time oxygen content data and real-time sludge particle temperature data into a feedback signal, and transmits the feedback signal to the control unit. The control unit is communicatively connected to the parameter monitoring unit. The control unit receives the feedback signal, parses the real-time oxygen content data and the real-time sludge particle temperature data in the feedback signal, generates control commands based on the parsed real-time oxygen content data and real-time sludge particle temperature data, and sends the control commands to the actuator. An actuator is communicatively connected to the control unit and communicates with the internal space. The actuator receives the control command and adjusts the flow rate of inert gas entering the internal space according to the control command.

2. The intelligent control system for inert gas in sludge drying based on oxygen concentration feedback according to claim 1, characterized in that, The parameter monitoring unit includes an oxygen acquisition module, which is installed in the internal space. The oxygen acquisition module acquires real-time oxygen content data of the internal space, and the real-time oxygen content data is the basic data for integrating the feedback signal.

3. The intelligent control system for inert gas in sludge drying based on oxygen concentration feedback according to claim 2, characterized in that, The parameter monitoring unit also includes a temperature acquisition module, which is installed in the internal space. The temperature acquisition module acquires the real-time sludge particle temperature data of the internal space, and the real-time sludge particle temperature data is the basic data for integrating the feedback signal.

4. The intelligent control system for inert gas in sludge drying based on oxygen concentration feedback according to claim 3, characterized in that, The control unit includes a signal receiving module, which is communicatively connected to the parameter monitoring unit. The signal receiving module receives the feedback signal transmitted by the parameter monitoring unit and parses the feedback signal to obtain the real-time oxygen content data and the real-time sludge particle temperature data.

5. The intelligent control system for inert gas in sludge drying based on oxygen concentration feedback according to claim 4, characterized in that, The control unit further includes an instruction generation module, which is communicatively connected to the signal receiving module. The instruction generation module acquires the parsed real-time oxygen content data and the real-time sludge particle temperature data, compares the acquired real-time oxygen content data and the real-time sludge particle temperature data with a preset safety threshold, and generates a control instruction for adjusting the corresponding inert gas flow rate based on the comparison result.

6. The intelligent control system for inert gas in sludge drying based on oxygen concentration feedback according to claim 5, characterized in that, The actuator includes an air intake regulating valve. The vertical drying granulation equipment is provided with an air intake port. The air intake regulating valve is installed at the air intake port. The air intake regulating valve is communicatively connected to the instruction generation module. The air intake regulating valve receives the control instruction and adjusts the valve opening according to the inert gas flow rate adjustment amount indicated by the control instruction.

7. The intelligent control system for inert gas in sludge drying based on oxygen concentration feedback according to claim 6, characterized in that, The preset safety threshold includes a first threshold. When the instruction generation module determines that the real-time oxygen content data obtained is greater than the first threshold, the instruction generation module generates a control instruction to increase the valve opening of the intake regulating valve, thereby increasing the flow rate of the inert gas introduced into the internal space through the intake regulating valve, so that the real-time oxygen content data of the internal space drops below the first threshold, where the first threshold is 3%.

8. The intelligent control system for inert gas in sludge drying based on oxygen concentration feedback according to claim 7, characterized in that, The preset safety threshold includes a second threshold. When the instruction generation module determines that the real-time sludge particle temperature data is greater than or equal to the second threshold, the instruction generation module generates a control instruction to increase the valve opening of the air intake regulating valve, thereby increasing the flow rate of the inert gas introduced into the internal space through the air intake regulating valve, so that the real-time sludge particle temperature data in the internal space drops below the second threshold, which is 90°C.

9. The intelligent control system for inert gas in sludge drying based on oxygen concentration feedback according to claim 8, characterized in that, It also includes an inert gas source. The intake regulating valve has an intake end. The inert gas source is connected to the intake end through a gas supply pipeline. The inert gas source stores inert gas. When the intake regulating valve is open, the inert gas flows along the gas supply pipeline through the intake regulating valve into the internal space.

10. The intelligent control system for inert gas in sludge drying based on oxygen concentration feedback according to claim 9, characterized in that, The vertical drying and granulation equipment is equipped with a discharge port, which outputs finished sludge particles with a particle size greater than or equal to 3 mm and less than or equal to 5 mm.

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