An ethylene oxide sterilization system and method of sterilization

Abstract

The application discloses an ethylene oxide sterilization system and a sterilization method, and belongs to the technical field of medical sterilization and disinfection. The system comprises: a plurality of intelligent mobile sterilization units, each unit being a sealed cabin body with autonomous mobile capability, used for accommodating products to be sterilized; a plurality of functional docking stations, including a loading docking station, a pretreatment docking station, a sterilization docking station, an analysis docking station and an unloading docking station arranged in sequence along the unit running path, each docking station being used for docking with the unit and providing corresponding functional support; and an intelligent scheduling control system in communication connection with the units and the docking stations, used for scheduling the mobile path and operation time sequence of the units. The application disperses the sterilization function from the centralized cabinet to a plurality of mobile units, combines the docking stations with different functions, realizes parallel flow line operation of the pretreatment, sterilization and analysis processes, significantly reduces the floor area, improves the sterilization efficiency, enhances the system expansibility, and guarantees the uniformity and stability of the sterilization process.

Description

Technical Field

[0001] This invention relates to the field of medical disinfection and sterilization technology, specifically to an ethylene oxide sterilization system and sterilization method. Background Technology

[0002] Ethylene oxide (EO) is a broad-spectrum, highly effective gaseous sterilizer capable of killing various microorganisms, including spores, at room temperature. Due to its excellent penetrability and compatibility with different materials, EO has become one of the primary low-temperature sterilization methods in fields such as medical devices, precision electronic instruments, and biopharmaceuticals. Traditional EO sterilization processes typically employ large, fixed sterilization cabinets. This traditional sterilization method suffers from the following drawbacks: First, traditional sterilization is mostly carried out in one or more large sterilization cabinets, each with a complete sterilization system. This not only occupies a large area with low space utilization but also incurs high costs. Furthermore, traditional sterilization systems are fixed installation projects, involving complex piping, electrical wiring modifications, and ventilation and exhaust system construction. Once installed, their processing capacity is locked, making it difficult to dynamically adjust or expand production capacity according to changes in production orders. If increased capacity is needed, a complete system often needs to be rebuilt, resulting in high investment costs and long construction periods. Second, each step in the sterilization process, such as pretreatment (heating and humidification), sterilization, and desorption (ventilation to remove residues), requires a considerable amount of time. For small-batch ethylene oxide sterilization, an entire sterilization cabinet is often required, leading to low sterilization efficiency. Third, for large sterilization cabinets, when sterilizing products, steps such as heating, humidification, vacuuming, ethylene oxide filling, and air circulation desorption are time-consuming and inefficient due to the large internal space. These cabinets are also prone to dead zones, uneven heating and humidification, poor insulation, and high energy consumption. Finally, in traditional methods, when products are transferred from the preheating chamber to the sterilization cabinet during material transfer, they often undergo a brief exposure process, resulting in heat loss and temperature fluctuations, which affect the stability and uniformity of the sterilization effect. Summary of the Invention

[0003] The purpose of this invention is to overcome the defects in the prior art and provide an ethylene oxide sterilization system and sterilization method.

[0004] To achieve the above objectives, the technical solution of this invention is to design an ethylene oxide sterilization system. Taking ethylene oxide sterilization as an example, however, this system can not only be used for ethylene oxide sterilization, but also for other sterilization processes similar to ethylene oxide sterilization, including: Multiple intelligent mobile sterilization units, each of which is a sealed chamber with autonomous movement capability, used to contain products to be sterilized; Multiple functional docking stations, including a loading docking station, a pretreatment docking station, a sterilization docking station, a desorption docking station, and an unloading docking station arranged sequentially along the operating path of the intelligent mobile sterilization unit, each of the functional docking stations being used to dock with the intelligent mobile sterilization unit and provide corresponding functional support; Pre-treatment docking station: Primarily uses humidification pipelines to transmit filtered and pressure-regulated industrial steam (water vapor) to increase humidity within the chamber; and uses heating circulation pipelines to transmit high-temperature heat transfer hot water to increase temperature within the chamber via heat exchangers. In addition to multiple passive docking interfaces, the station also includes an industrial steam generator, a water treatment system (to ensure steam purity), a hot water boiler and circulation pumps, as well as safety sensors for monitoring the station's environment.

[0005] Sterilization docking station: Primarily, gaseous ethylene oxide (usually derived from the vaporization of liquid EO) is transferred via ethylene oxide supply pipelines; gas is transferred during the vacuuming phase (removing air from the chamber) via vacuum pump interfaces, and ethylene oxide exhaust gas is transferred at the end of the sterilization phase (to be discharged into the tail gas treatment system); high-purity nitrogen is transferred during the purging phase for purging and cleaning the interfaces. In addition to a closed structure, automatic doors, air circulation devices, and multiple sets of passive docking interfaces, the station also includes an EO storage tank area and vaporizer, vacuum pump sets, a tail gas treatment system (acid absorption tower or catalytic combustion device), a gas leak alarm and linkage control system, and a fire protection system.

[0006] The desorption docking station primarily transmits clean air filtered by a HEPA filter through a fresh air intake pipe and exhaust gas containing a high concentration of EO through an exhaust gas discharge pipe. In addition to multiple passive docking interfaces, the station also includes high-power supply and exhaust fans, HEPA filter units, exhaust gas pretreatment devices (such as activated carbon adsorption boxes), an airflow balance control system, and an optional auxiliary heating system to maintain the desorption temperature.

[0007] The intelligent scheduling and control system is communicatively connected to the intelligent mobile sterilization unit and the functional docking station, and is used to schedule the movement path and operation sequence of the intelligent mobile sterilization unit.

[0008] This invention transforms the traditional large, fixed sterilization cabinet that integrates all functions into a distributed, collaborative operation mode that combines multiple autonomously mobile sterilization units with fixed stations of varying functions. By setting up one or two complete systems (one for operation and one for backup to prevent malfunctions from preventing the entire sterilization process from failing) at the pretreatment docking station, sterilization docking station, and analysis docking station, and by providing multiple functional interfaces for interfacing with the intelligent mobile sterilization units, savings in space and cost are achieved. Furthermore, compared to large sterilization cabinets, the intelligent mobile sterilization units are smaller in size and have less internal space. Although they process smaller volumes per cycle, they are highly efficient in heating, humidifying, sterilizing, and analyzing, and provide uniform heating and humidifying, resulting in superior sterilization effects.

[0009] Specifically, the intelligent mobile sterilization unit includes a cabin and a mobile chassis located at the bottom of the cabin. The cabin is equipped with an automatically opening and closing sealed door. The cabin has multiple interfaces for docking with pretreatment, sterilization, and analysis stations, respectively. Each interface is configured according to process requirements; interfaces with similar functions can be the same on the cabin (i.e., multiple interfaces can be combined according to function). For example, if each stage requires the introduction of gas (steam or clean air), only one interface needs to be provided on the cabin to dock with the corresponding interface of each station. To avoid cross-contamination or connection errors, different interfaces can be set up independently for physical isolation. For example, the pretreatment interface is specifically for transmitting humidifying steam, the sterilization interface is specifically for transmitting ethylene oxide gas and connecting vacuum pipelines, and the analysis interface is specifically for transmitting clean air and discharging waste gas. The interfaces typically contain gas passages, liquid passages, and electrical connectors.

[0010] Optionally, the cabin is also equipped with a product identification module, including an RFID reading unit and a visual recognition system, which is used to automatically identify product batch information during loading and bind it with sterilization data to achieve contactless traceability from loading to unloading.

[0011] The chamber is equipped with an internal environment monitoring module, which includes temperature, humidity, gas concentration, and pressure monitoring units. This module monitors the sterilization environment parameters in real time and is crucial for ensuring the sterilization process complies with regulatory requirements (such as ISO 11135). The temperature monitoring units (multiple PT100 platinum resistance thermometers or thermocouples), humidity monitoring units (temperature and humidity transmitters installed at the return air vents), gas concentration monitoring units (ETO ethylene oxide sensors), and pressure monitoring units (pressure sensors) collect data in real time, which is then recorded and processed by the onboard controller. This data serves as the basis for closed-loop control and the generation of sterilization batch reports that meet quality system requirements, enabling full traceability of the sterilization process.

[0012] The cabin is equipped with an onboard controller electrically connected to the mobile chassis, the docking interface, and the cabin environment monitoring module. This controller is used to control the autonomous operation of the intelligent mobile sterilization unit. The onboard controller employs an embedded industrial computer running a real-time operating system. It is responsible for receiving instructions from the central intelligent scheduling and control system, coordinating the navigation and movement of the mobile chassis, controlling the opening and closing of the sealed doors, communicating with the docking station during docking and controlling the opening and closing of valves at the corresponding interface, and simultaneously collecting and storing data from the environment monitoring module. Even when disconnected from the central system or in the event of communication interruption, the onboard controller ensures that the unit completes its predetermined basic tasks, guaranteeing system reliability.

[0013] Optionally, the intelligent mobile sterilization unit is equipped with a heating and temperature control module. After detaching from the docking station, the intelligent mobile sterilization unit needs to maintain the internal temperature during movement. Although the docking station can provide a heat source during docking, maintaining the temperature during movement is crucial. This solution integrates a heating and temperature control module (such as an explosion-proof PTC ceramic heater or an electric heating film) inside the unit, along with an internal fan for forced convection circulation, enabling the unit to maintain its own temperature. This allows the unit to actively heat itself to compensate for heat loss during movement from the pretreatment docking station to the sterilization docking station, or from the sterilization docking station to the desorption docking station, ensuring that the internal temperature remains stable within the process requirements and guaranteeing the consistency and stability of the sterilization effect.

[0014] Optionally, the intelligent mobile sterilization unit further includes a phase change heat storage unit, which is integrated into the wall of the chamber and used to slowly release heat energy into the chamber after detaching from the docking station to maintain the sterilization temperature. During docking at the pretreatment or sterilization docking station, the phase change heat storage unit in the chamber wall can be heated by an external heating device, causing the phase change material to melt and store a large amount of heat energy. When the intelligent mobile sterilization unit detaches from the docking station, as the ambient temperature decreases, the phase change material gradually solidifies, and in this process, the stored latent heat is slowly and evenly released into the chamber.

[0015] Furthermore, the cabin is also equipped with a circuit interface for docking with the functional docking stations. This circuit interface enables the intelligent mobile sterilization unit to charge and perform high-speed data communication during docking. The mobile chassis is typically powered by batteries, requiring energy replenishment for extended periods of movement and operation. When the unit is docked at any functional docking station for processing, it can connect to the station's power supply system via the circuit interface for automatic charging (i.e., "charging while working"), ensuring sufficient power for the next move and achieving automatic energy replenishment. Simultaneously, this interface can also serve as the physical layer for Ethernet or industrial bus communication, allowing for high-speed uploading of sterilization process data stored on the onboard controller to the central control system during docking, or downloading new task instructions, achieving synchronous docking of energy and data.

[0016] Preferably, the pretreatment docking station, sterilization docking station, and analytical docking station are all equipped with multiple sets of passive docking interfaces. Each passive docking interface includes a main interface and a backup interface, and is equipped with a positioning component, an electromagnetic locking device, and a self-testing module. Multiple sets of passive docking interfaces allow one sterilization docking station to dock with multiple intelligent mobile sterilization units simultaneously. For example, a sterilization docking station can be designed with 4 or 6 docking bays, each independently equipped with an ethylene oxide gas supply pipeline, a vacuum pump interface, and a corresponding control valve. Thus, even if the sterilization process itself is time-consuming, by increasing the number of docking interfaces, the station can simultaneously provide sterilization gas to multiple units. The passive docking interfaces are typically standardized in design, featuring guiding, locking, and sealing functions to ensure that the units can quickly and accurately dock and establish an airtight connection. Furthermore, when increasing production capacity later, only the number of passive docking interfaces and intelligent mobile sterilization units needs to be increased. When the functional docking station docks with the intelligent mobile sterilization unit, it is first positioned by a positioning component, which includes a laser positioning module and a mechanical guiding mechanism. The laser positioning module performs coarse positioning, and the mechanical guiding mechanism performs fine positioning. Finally, it is fixed by an electromagnetic locking device and triggers the airtightness self-test module. If the self-test fails, the system automatically switches to the backup interface and alarms to prompt maintenance.

[0017] Preferably, the pretreatment docking station, sterilization docking station, and analytical docking station are all multi-layered structures, each equipped with at least one set of lifting units. The height of the intelligent mobile sterilization unit is smaller than that of a traditional sterilization cabinet; therefore, to further reduce the system's horizontal footprint, the functional docking station is designed as a two-, three-, or even higher three-dimensional warehouse structure. Multiple docking interfaces are provided on each floor. When the intelligent mobile sterilization unit arrives at the station, it first enters the lifting unit, which then raises or lowers it to the designated floor, and then docks with the passive docking interface on the corresponding floor. This three-dimensional layout fully utilizes the vertical space of the factory, and the system's processing capacity can be multiplied within the same floor area.

[0018] Preferably, the entire sterilization docking station is a closed structure, equipped with multiple automatically opening and closing access doors and an air circulation device. The station also includes leak detection sensors, an emergency spray or neutralization unit, and a multi-level safety protection unit. The access doors, leak detection sensors, and emergency spray or neutralization unit are all linked to the multi-level safety protection unit. To prevent ethylene oxide leaks from causing personal injury or environmental pollution, the entire sterilization docking station is enclosed in an independent room or cabinet using airtight materials (such as color steel plates or stainless steel plates), leaving only an automatic door for the intelligent mobile sterilization unit to enter and exit. The automatic door opens when the unit enters or exits and remains closed at other times, effectively preventing ethylene oxide gas from leaking to other areas of the workshop. The station is equipped with an independent ventilation system and exhaust gas treatment device. In the event of an accidental leak during sterilization, the circulation device can promptly draw the ethylene oxide-containing air into a catalytic decomposition or acid absorption device for harmless treatment. The multi-level safety protection unit includes: the first level is a real-time leak monitoring sensor installed at all docking interfaces. Once a trace EO leak is detected, an alarm is immediately triggered and the system is automatically tightened. At the same time, the air circulation device is activated to promptly expel the leaked gas. The second level is a leak monitoring sensor installed at the ethylene oxide pipeline. When a leak is detected in the pipeline, all entrance and exit doors of the sterilization docking station are closed to prevent internal gas from leaking out. In addition, an emergency spray or neutralization unit installed in the sterilization docking station can be automatically activated when the leak exceeds the limit to neutralize the leaked gas inside.

[0019] Preferably, the intelligent mobile sterilization unit further includes a power supply guarantee unit, comprising: a main power supply, which is a high-energy-density lithium battery pack; an auxiliary power supply, which is a supercapacitor module, used for short-term high-power output (such as door opening, emergency movement); and an emergency power supply, which is a replaceable backup battery pack, automatically activated or sending a rescue request when the power level is below a threshold. The intelligent scheduling and control system is equipped with a power prediction and active recharging algorithm, which dynamically decides whether the unit should prioritize returning to charging or have the backup unit take over to complete the sterilization based on the current power level, the energy consumption required for the remaining tasks, and the path length. It should be noted that when the power supply guarantee unit docks at each docking station, the circuit interface can charge the battery pack, capacitor module, backup battery, etc. Setting up a power supply guarantee unit is also to prevent the entire process from being disrupted due to unexpected power outages during operation, causing losses to the enterprise. In addition, the power supply guarantee unit also ensures improved automation and reduced manual intervention.

[0020] Optionally, the mobile chassis can be a rail-guided shuttle or an automated guided vehicle (AGV). Rail-guided shuttle (RGV): Suitable for scenarios with fixed paths. Steel rails need to be laid on the workshop floor. The RGV runs at high speed along the rails, typically powered by a sliding contact line, allowing for 24-hour uninterrupted operation. Its positioning accuracy can reach ±2mm, which is more advantageous for ensuring accurate docking of interfaces. Automated guided vehicle (AGV): Suitable for scenarios with complex paths and requiring high flexibility. Typically powered by batteries, the vehicle will be forced to recharge when the battery level drops below 30%, and will be recharged during idle periods when the battery level is between 60-80%. AGVs can achieve trackless autonomous driving through laser navigation, magnetic strip navigation, or QR code navigation, and their path changes are flexible. The advantages of AGVs are more obvious when the system needs frequent layout adjustments or obstacle avoidance. The appropriate choice can be made based on the specific conditions of the factory.

[0021] Furthermore, the intelligent dispatch and control system incorporates a distributed traffic control module, employing a time-window-based path planning algorithm and a reserved buffer mechanism. Each functional docking station has 2-3 queuing buffer zones for units waiting to dock to temporarily stop. The system calculates the optimal path for each unit in real time and reserves time windows for each road segment and station to prevent multiple units from simultaneously competing for the same resource. A priority scheduling strategy is introduced to dynamically adjust the queuing order based on product type, sterilization urgency, and remaining unit power. When a potential deadlock is detected, a deadlock resolution algorithm is automatically triggered, ordering lower-priority units to yield or detour.

[0022] Furthermore, it includes an automated cleaning and maintenance docking station, used for internal cleaning, drying, sealing testing, and calibration of the intelligent mobile sterilization unit after multiple sterilization cycles. The unit automatically schedules its entry into the maintenance station at preset intervals, achieving automated management throughout its entire lifecycle. Through autonomous automatic cleaning and maintenance, the lifespan of each intelligent mobile sterilization unit can be maximized, and the entire process is automated; human intervention is only required when a malfunction necessitates repair, thus demonstrating a high degree of automation.

[0023] The technical solution of this invention is to design an ethylene oxide sterilization method, comprising: Step S1: At the loading docking station, the product to be sterilized is loaded into the intelligent mobile sterilization unit, and the intelligent mobile sterilization unit automatically closes the sealing door; Step S2: The intelligent mobile sterilization unit autonomously travels to the pretreatment docking station, docks with the pretreatment docking station, and performs preheating and prehumidification treatment; Step S3: After the pretreatment is completed, the intelligent mobile sterilization unit detaches from the pretreatment docking station, autonomously travels to the sterilization docking station, docks with the sterilization docking station, and introduces ethylene oxide gas for sterilization. Step S4: After sterilization is completed, the intelligent mobile sterilization unit detaches from the sterilization docking station, autonomously travels to the analysis docking station, docks with the analysis docking station, and performs ventilation analysis to reduce the residual ethylene oxide gas. Step S5: After the analysis is completed, the intelligent mobile sterilization unit autonomously travels to the unloading docking station, automatically opens the sealed door, and takes out the sterilized product; Step S6: The unloaded intelligent mobile sterilization unit travels to the loading docking station via the return channel and enters the next working cycle; In steps S2 to S4, during the movement of the intelligent mobile sterilization unit after detaching from the docking station, the temperature inside the chamber is maintained by the heat energy released by the phase change heat storage unit or the heating and temperature control module.

[0024] The advantages and beneficial effects of this invention are as follows: In traditional systems, a batch of products must undergo pretreatment, sterilization, and analysis sequentially before the next batch can begin. The time consumed in each step leads to low utilization of the entire sterilization cabinet. In this invention, multiple independent intelligent mobile sterilization units exist, which can operate in a streamlined or parallel manner. This significantly increases the overall processing capacity of the system, theoretically enabling 24-hour uninterrupted streamlined operation and solving the inefficiency problems caused by small batches of products occupying the entire cabinet and waiting for processes. By decomposing the fixed sterilization cabinet into mobile sterilization units and functional stations, and adopting a three-dimensional layout, the system layout becomes more compact and flexible, reducing the floor space by more than 30% compared to traditional sterilization cabinets with the same processing capacity. The functional docking stations are designed as a three-dimensional warehouse structure, further reducing the floor space per unit capacity. Furthermore, when capacity increases, only the number of passive docking interfaces and intelligent mobile sterilization units needs to be increased, resulting in low expansion costs. Compared to the traditional method of setting up a complete sterilization system for each sterilization cabinet, the cost is significantly reduced. Furthermore, the volume of each intelligent mobile sterilization unit is significantly smaller than that of traditional large sterilization cabinets. During heating, humidification, vacuuming, and gas filling, the smaller space significantly shortens processing time, and allows for rapid and uniform temperature, humidity, and gas concentration, effectively avoiding the dead zones and unevenness issues common in large cabinets. Simultaneously, the smaller chamber facilitates better insulation. The product is sealed within the intelligent mobile sterilization unit from the moment it is loaded and remains in this closed environment throughout the pretreatment, sterilization, and desorption processes. During movement after detaching from the docking station, the unit maintains the internal environment through its own temperature control system, completely avoiding heat loss and temperature fluctuations during the transfer from the preheating chamber to the sterilization cabinet, as is common in traditional processes, ensuring the stability and uniformity of sterilization. In addition, this invention, by introducing dual redundant self-sealing docking interfaces, a power supply guarantee unit, a safety protection unit, and an automatic cleaning and maintenance docking station, constructs a complete sterilization ecosystem with high reliability, high safety, and full lifecycle management capabilities, improving the overall system's safety, lifespan, and automation level. Attached Figure Description

[0025] Figure 1 This is a layout diagram of the sterilization system of the present invention; Figure 2 This is a schematic diagram of the intelligent mobile sterilization unit of the present invention; Figure 3 This is a schematic diagram of the multi-layer docking station of the present invention. Detailed Implementation

[0026] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0027] This invention provides an ethylene oxide sterilization system, the core of which lies in breaking down the traditional centralized sterilization process into a distributed, modular, collaborative operation.

[0028] The system mainly consists of three parts: multiple intelligent mobile sterilization units, multiple functional docking stations, and an intelligent scheduling and control system.

[0029] like Figure 1 As shown, the functional docking stations include loading docking stations, pretreatment docking stations, sterilization docking stations, analytical docking stations, and unloading docking stations arranged sequentially along the preset operating path of the intelligent mobile sterilization unit. These docking stations are no longer simple material platforms, but functional stations integrating complex process pipelines. In actual plant layouts, these docking stations can be flexibly arranged according to the spatial shape, such as in a straight line, U-shape, or L-shape, and they are connected by the travel channels of AGVs or RGVs. In another embodiment, considering the characteristics of some large medical device sterilization plants with single product types, fixed logistics paths, and extremely high throughput, the mobile chassis is a rail-guided shuttle vehicle (RGV). In this case, the ground of the entire system needs to be laid with precision steel rails. The RGV runs at high speed along the rails, usually powered by a sliding contact line, enabling uninterrupted operation around the clock. Its positioning accuracy can reach ±2mm, which is higher than that of AGVs, making it more advantageous for ensuring accurate docking of the docking interfaces. At the same time, the passive docking interfaces of the functional docking stations are also designed with mechanical guiding devices to ensure that the RGV can successfully dock in one go. Correspondingly, the traffic control module in the intelligent dispatch control system is also switched to interlocking logic control suitable for rail systems to prevent RGVs from colliding on the track. Although this solution is slightly less flexible (the path cannot be changed arbitrarily), it has higher operating efficiency and stability.

[0030] The intelligent scheduling and control system, serving as the decision-making core, typically consists of a high-performance industrial server, a database, and a Manufacturing Execution System (MES) and Warehouse Management System (WMS) running on it. It communicates in real-time with all intelligent mobile sterilization units and functional docking stations via industrial wireless networks (such as WiFi 6 and 5G), responsible for overall task allocation, traffic control, and status monitoring. The intelligent scheduling and control system incorporates a reinforcement learning-based dynamic scheduling algorithm that optimizes task allocation and path planning in real-time based on the load status of each docking station, the real-time process parameters of the sterilization unit, product priorities, and energy consumption models, maximizing overall system throughput and minimizing energy consumption. The system also connects to a digital twin platform, mapping the physical system's operating status in real-time, enabling offline simulation testing and online optimization simulations, predicting system bottlenecks in advance, and optimizing scheduling strategies.

[0031] like Figure 2As shown, the intelligent mobile sterilization unit includes a sealed chamber made of 304L stainless steel inner liner and high-density polyurethane insulation layer to ensure good thermal insulation performance and corrosion resistance. The front of the chamber is equipped with an automatically opening and closing sealing door controlled by an onboard controller. The door is surrounded by an inflatable silicone sealing ring to ensure absolute airtightness when closed. The opening method of the sealing door depends on the specific factory conditions and the actual situation of the loading docking station; it can be a single-leaf swing opening or a complete tilting opening to one side via a cylinder and linkage mechanism.

[0032] A mobile chassis is installed at the bottom of the cabin. In this embodiment, the mobile chassis is a laser-guided automated guided vehicle (AGV), which includes drive wheels, omnidirectional wheels, laser navigation sensors, safety touch edges and power battery packs, enabling precise positioning and autonomous obstacle avoidance.

[0033] To achieve precise docking with different functional stations, the rear and sides of the cabin integrate multiple sets of dedicated docking interfaces. Specifically, these include a pretreatment interface for connecting to a pretreatment docking station, a sterilization interface for connecting to a sterilization docking station, and a resolution interface for connecting to a resolution docking station. These interfaces are all quick-connect, self-sealing connectors, containing gas channels and probes for signal exchange. When the interface engages with the station's passive docking interface, automatic gas and electrical connections are established. In another embodiment, the bottom or side of the cabin also features a circuit interface for charging and data uploading.

[0034] The cabin is equipped with an internal environmental monitoring module, which includes a temperature monitoring unit (multi-point PT100 platinum resistance thermometers), a humidity monitoring unit (temperature and humidity transmitters installed at the return air vent), an ethylene oxide gas concentration monitoring unit (ETO ethylene oxide sensor), and a pressure monitoring unit (pressure sensor). These sensors collect data in real time and transmit it to the onboard controller.

[0035] In addition, the cabin is equipped with a product identification module, including an RFID reading unit and a visual recognition system, which automatically identifies product batch information during loading and binds it with sterilization data to achieve contactless traceability from loading to unloading.

[0036] To maintain the sterilization temperature, in one embodiment, a heating and temperature control module is installed inside the chamber, specifically an explosion-proof PTC ceramic heater, which works in conjunction with an internal fan to perform forced convection circulation, ensuring that the temperature uniformity inside the chamber is within ±3℃.

[0037] In another embodiment, a phase change thermal energy storage unit is integrated into the inner wall interlayer of the chamber. This unit consists of multiple metal plates filled with phase change material, the phase change temperature of which is selected according to the sterilization process requirements. During docking at the pretreatment or sterilization docking station, the phase change material absorbs heat and melts to store thermal energy; during movement away from the station, the phase change material gradually solidifies, slowly releasing latent heat to maintain the internal temperature of the chamber.

[0038] Regarding power supply, this embodiment of the intelligent mobile sterilization unit is also equipped with a power supply guarantee unit: the main power supply is a high-energy-density lithium battery pack, which can meet more than 4 hours of continuous operation; the auxiliary power supply is a supercapacitor module, used for short-term high-power output (such as opening doors, emergency movement); the emergency power supply is a replaceable backup battery pack, which automatically activates or sends a rescue request when the power level is below a threshold. The intelligent scheduling and control system also has a power prediction and active recharging algorithm, which dynamically decides whether the intelligent mobile sterilization unit should return to charging first or be taken over by the backup unit based on the current power level, the energy consumption required for the remaining tasks, and the path length. The power supply guarantee unit must meet certain waterproof requirements and be properly sealed, dustproof, and corrosion-resistant.

[0039] The airborne controller uses an embedded industrial computer running a real-time operating system, and is responsible for receiving instructions, controlling movement, driving interfaces, collecting data, and recording logs.

[0040] like Figure 1 As shown, the detailed structure and working process of each functional docking station are as follows: 1. Loading docking station and unloading docking station The loading and unloading docking stations have relatively simple structures, mainly consisting of a platform with a positioning guide groove. At the loading docking station, operators or automated loading robots push pallets containing the products to be sterilized into the docked and positioned intelligent mobile sterilization unit. The operator then presses the start button, or the system automatically triggers the process, and the sealed door closes automatically. The unloading docking station has the same structure and is used for retrieving finished products.

[0041] 2. Pre-treatment docking station The pretreatment docking station is a preparation site for ethylene oxide sterilization, primarily providing "preheating" and "prehumidification" functions. This station has multiple sets of passive docking interfaces, capable of serving multiple units simultaneously. The passive docking interfaces employ a dual-redundant self-sealing structure, including a main interface and a backup interface. During docking, a laser positioning module performs coarse positioning (accuracy ±5mm), followed by a mechanical guiding mechanism for fine positioning (accuracy ±0.5mm). Finally, an electromagnetic locking device secures the interface and triggers an airtightness self-test procedure. If the self-test fails, the system automatically switches to the backup interface and issues an alarm prompting maintenance.

[0042] Once the intelligent mobile sterilization unit enters and docks accurately, the pretreatment interface tightly connects with the station's passive docking interface. At this point, saturated or supersaturated water vapor generated by the industrial humidifier within the station is injected into the unit chamber through humidification pipes and after filtration. The onboard controller adjusts the humidification valve based on feedback from the humidity monitoring unit until the relative humidity inside the chamber reaches the pretreatment requirements. Simultaneously, the station's hot water circulation system or electric heating system connects to the heating coils or heat exchangers inside the chamber via heating circulation pipes, heating the chamber temperature and stabilizing it at the set preheating temperature (if a heating temperature control module is installed inside the chamber, heating is not required here; instead, the heating is handled by the heating temperature control module). After pretreatment is complete, the onboard controller records the temperature and humidity curves for the pretreatment stage.

[0043] 3. Sterilization docking station The sterilization docking station is the part of the entire system with the highest safety requirements. The entire sterilization docking station is constructed into a closed structure using airtight materials. This closed structure is equipped only with an automatic switchable access door for unit entry and exit (multiple doors can be provided to facilitate the entry and exit of multiple intelligent mobile sterilization units). When a unit needs to enter, the door opens; after the unit has fully entered and docked with the interface, the door closes, completely isolating the sterilization area from the outside world.

[0044] The sterilization docking station is also equipped with leak detection sensors, emergency spray or neutralization units, and multi-level safety protection units. The entrance doors, air circulation devices, leak detection sensors, and emergency spray or neutralization units are all linked to the multi-level safety protection units. Real-time leak detection sensors installed at all docking interfaces immediately alarm and automatically tighten upon detecting even a trace EO leak, while simultaneously activating the air circulation device to promptly expel the leaked gas. Leak detection sensors located at ethylene oxide pipelines (usually multiple, placed in areas with dense ethylene oxide pipelines and at locations prone to leaks such as ethylene oxide tanks and valves) detect leaks in the pipelines. Upon detection, all entrance and exit doors of the sterilization docking station immediately close to prevent internal gas leakage. Additionally, the emergency spray or neutralization units installed within the sterilization docking station automatically activate when leakage exceeds the limit, neutralizing the leaked gas.

[0045] The sterilization docking station also features multiple passive docking interfaces. It is equipped with a complete ethylene oxide supply system, including an ethylene oxide storage tank, a vaporizer, and a precision flow control valve assembly, connected to the passive docking interfaces via ethylene oxide supply pipelines. Additionally, the station is equipped with a water ring or rotary vane vacuum pump, connected to the unit via a vacuum pump interface, used for pre-sterilization vacuuming and post-sterilization gas replacement. Typically, two sets of ethylene oxide supply and vacuum pump systems are configured, one for operation and one as a backup, to prevent disruption to the sterilization process in case of unexpected malfunctions or maintenance of one system.

[0046] Once the intelligent mobile sterilization unit completes docking and the sealed door closes, the sterilization process automatically begins: first, a vacuum pump evacuates the chamber to remove air; then, ethylene oxide gas is introduced, and a heating and temperature control module or phase change heat storage unit maintains a precise sterilization temperature. During the sterilization holding phase, the chamber's environmental monitoring module continuously monitors gas concentration and pressure, and replenishes gas through closed-loop control. After sterilization, the gas is drawn back to the exhaust gas treatment system for neutralization. Throughout the process, in the event of a leak, the gas concentration monitor within the sealed structure will immediately sound an alarm and activate the air circulation device (including a high-efficiency filter and a catalytic decomposition module) to extract and treat the leaked gas, ensuring safety. The air circulation device maintains a slightly negative pressure state throughout the sealed structure, preventing gas leakage. During sterilization, after ethylene oxide gas is introduced and the concentration reaches the required level, the intelligent mobile sterilization unit can detach from the passive docking interface to facilitate use by other intelligent mobile sterilization units. After detachment, it moves to another area for sterilization. If the ethylene oxide concentration falls below the set value during sterilization, it can return to any passive docking interface for replenishment. Due to the small internal space of the intelligent mobile sterilization unit, ethylene oxide loss is minimized, and the time required for filling with ethylene oxide is reduced. The ethylene oxide also allows for better contact between the gas and the product being sterilized, significantly improving sterilization efficiency and effectiveness.

[0047] 4. Analysis of docking stations The analytical docking station is used to remove ethylene oxide residues from products and packaging materials after sterilization. Its structure is similar to the pretreatment docking station, also an open or semi-open platform with multiple sets of passive docking interfaces.

[0048] Once the intelligent mobile sterilization unit is docked, the desorption interface connects to the passive docking interface of the station. A high-powered fan inside the station forces clean air, filtered through a high-efficiency particulate air (HEPA) filter, into the unit chamber through a fresh air intake pipe. Simultaneously, air containing ethylene oxide is extracted through an exhaust pipe and sent to a specialized catalytic decomposition or activated carbon adsorption device for treatment. Through continuous ventilation, the ethylene oxide concentration inside the chamber rapidly decreases until it reaches safety standards. To accelerate desorption, the desorption docking station can also maintain the chamber temperature using heated circulation piping. During desorption, the relatively small internal space of the intelligent mobile sterilization unit allows for faster air replacement, better air circulation, and higher desorption efficiency.

[0049] 5. Automatic cleaning and maintenance docking station The automatic cleaning and maintenance docking station is used to perform internal cleaning, drying, sealing testing and calibration of the intelligent mobile sterilization unit after it has completed multiple sterilization cycles; the unit automatically schedules to enter the maintenance station every preset number of times, realizing automated management of the entire life cycle.

[0050] The system is configured with a 4-station automatic cleaning and maintenance docking station (preferably set before the loading docking station or after the unloading docking station, because the intelligent mobile sterilization unit is in an empty state at this time). Each station operates independently and can serve 4 intelligent mobile sterilization units simultaneously to achieve parallel processing of maintenance operations. During automatic cleaning and maintenance, it is necessary to avoid affecting precision components such as batteries as much as possible.

[0051] Maintenance trigger mechanism: The intelligent scheduling control system establishes an operation counter for each intelligent mobile sterilization unit, and the count is incremented by 1 for each completed sterilization cycle. When the count reaches the set value, the system automatically marks the unit as "needing maintenance" and schedules it to the automatic cleaning and maintenance docking station after its current task is completed. At the same time, the system reserves an idle maintenance station and generates a personalized maintenance plan containing the unit's historical operation data. After the unit enters the maintenance station, it first undergoes identity verification in the positioning area at the entrance. Subsequently, the hatch of the intelligent mobile sterilization unit, the bottom drainage valve, and the valves at each docking interface are opened to start cleaning.

[0052] Cleaning process: The control module starts the high-pressure spray pump to spray warm water for 3 minutes. The spray head moves along a preset trajectory driven by a servo motor or a robotic arm to ensure full coverage of the inner wall of the cabin, the inner side of the sealing door, and the inside of each interface. The wastewater is discharged from the drainage valve at the bottom of the cabin and flows into the neutralization tank through the collection tank at the bottom of the station. After the clean water spray, a mixture of neutral cleaning agent and deionized water in another spray head is used to rinse the inside of the cabin. Finally, another clean water rinse is carried out.

[0053] Drying process: The clean air purified by the HEPA filter is heated and blown towards the inner wall of the cabin through multiple air nozzles. The hot air drying lasts for 20 minutes, and the humidity sensor in the station monitors the exhaust humidity. When the humidity drops to 25%RH, the hot air drying ends.

[0054] Detection process: Airtightness test: Compressed air is filled into the cabin to 50 kPa, the valve is closed, and the pressure is maintained for 30 - 60 minutes. The pressure sensor continuously monitors, and if the pressure drop is less than the qualified standard, the airtightness is qualified. Sensor calibration: The robotic arm of the calibration device automatically inserts the standard temperature probe and the standard humidity probe into the preset calibration interfaces in the cabin. Three temperature points of 30°C, 45°C, and 60°C and three humidity points of 30%RH, 60%RH, and 80%RH are output in sequence, and the readings of the sensors built into the unit are recorded. If the temperature deviation ≤ ±1°C and the humidity deviation ≤ ±5%RH, it is within the range and no correction is required. Visual inspection: The high-resolution camera scans and photographs the sealing door, the sealing ring, and the inside of the interface along the guide rail. The AI image recognition algorithm analyzes in real time. There are slight indentations but no cracks on the surface of the sealing ring, the inside of the interface is clean without residues, and the inner wall of the cabin is smooth without corrosion. The detection images and the judgment results are stored in the maintenance file.

[0055] Maintenance Completion and Exit: After all test items pass, the control module generates a complete maintenance report, including cleaning parameters, drying curves, test data, calibration records, etc. The report is then uploaded to the intelligent scheduling and control system after being bound to the unit ID. The unit status is updated to "Maintained, Available," and it automatically leaves the workstation and returns to the standby area.

[0056] Anomaly Handling: If sensor deviation exceeds limits during testing, the system automatically performs correction. If the system still fails to meet the requirements after correction, an alarm message "Sensor needs replacement" is generated, and the unit is moved to the "repair area" to await manual intervention. If the airtightness test fails, the system automatically performs a second test. If the test still fails, the leak location procedure is initiated. A small amount of helium is introduced into the chamber, and a helium mass spectrometer is used to detect the leak point. Once the leak is accurately located, an alarm is triggered to prompt repair.

[0057] The maintenance station also has a self-cleaning program. After every 10 units of maintenance are completed, the station will automatically start cleaning to clean the pipes, nozzles, collection tanks, etc., to prevent cross-contamination and pipe blockage.

[0058] The intelligent dispatching and control system is the system's control unit. Its working logic is as follows: Task generation: The MES system generates sterilization tasks based on production orders.

[0059] Resource matching: The system monitors the status of all intelligent mobile sterilization units (location, power level, cleanliness, current task) and the busy / idle status of all functional docking stations in real time.

[0060] Path planning and scheduling: A loading task is assigned to an idle unit, and it is instructed to proceed to the loading docking station. Simultaneously, an idle interface at the preprocessing docking station and its start time are reserved. Once the unit completes loading, the system plans the optimal route based on traffic conditions and instructs it to proceed to the designated preprocessing interface. During this process, the distributed traffic control module employs a time-window-based path planning algorithm and a reserved buffer mechanism. Each functional docking station has 2-3 queuing buffers for waiting units to temporarily stop. The system calculates the optimal route for each unit in real time and reserves time windows for each road segment and station to prevent multiple units from simultaneously competing for the same resource. A priority scheduling strategy is introduced, dynamically adjusting the queuing order based on product type, sterilization urgency, and remaining unit power. When a potential deadlock is detected, a deadlock resolution algorithm is automatically triggered, ordering lower-priority units to yield or detour.

[0061] Dynamic adjustment: If a sterilization docking station fails, the system will immediately reschedule the subsequent units to other normal sterilization docking stations and recalculate the operation sequence of all units to ensure maximum overall efficiency.

[0062] Based on the above system, the present invention also provides an ethylene oxide sterilization method, the specific process of which is as follows: Step S1 (Loading): The intelligent scheduling and control system dispatches an empty intelligent mobile sterilization unit to the loading docking station and positions it. The operator or robotic arm loads the product to be sterilized into the unit, and the product identification module automatically identifies the product batch information and binds it to the sterilization data. The sealing door then automatically closes. The onboard controller reports "Loaded, awaiting processing" to the central system.

[0063] Step S2 (Pre-treatment): The central system instructs the intelligent mobile sterilization unit to travel to the designated pre-treatment docking station and precisely dock with one of the passive docking interfaces. During docking, the laser positioning module and mechanical guiding mechanism work together to achieve precise positioning. After the electromagnetic locking device is fixed, an airtightness self-check is triggered to ensure reliable sealing. After successful docking, the pre-treatment docking station injects steam into the chamber through the pre-treatment interface and heats it for preheating and prehumidification. The chamber environment monitoring module monitors the data in real time to ensure that the set values ​​are reached and maintained for the set time. After treatment is completed, the interface disengages.

[0064] Step S3 (Sterilization): The intelligent mobile sterilization unit detaches from the pretreatment docking station, releasing heat energy through its phase change thermal storage unit (or activating the heating and temperature control module) to maintain the internal temperature during movement. The power supply unit monitors the power consumption in real time and dynamically adjusts the energy allocation strategy based on the remaining path length and energy consumption prediction. According to the central dispatch, the intelligent mobile sterilization unit travels to the entrance of the sterilization docking station, the automatic door opens, and the unit enters and docks with the sterilization interface. The automatic door closes. The sterilization docking station automatically executes procedures such as vacuuming, chemical dosing, pressure sterilization, and venting. Data from the entire process is recorded in real time.

[0065] Step S4 (Analysis): After sterilization, the automatic door of the sterilization docking station opens, and the intelligent mobile sterilization unit moves out. It maintains the temperature using heat storage or active heating and moves to the analysis docking station for docking. The analysis docking station uses a forced ventilation interface to analyze and reduce ethylene oxide residue.

[0066] Step S5 (Unloading): After successful analysis, the intelligent mobile sterilization unit travels to the unloading docking station. The sealed door opens automatically, and the product is removed. Upon product removal, the system automatically binds the entire sterilization process data with the product batch information, generating a traceable sterilization report.

[0067] Step S6 (Cycle): The unloaded intelligent mobile sterilization unit travels to the loading docking station via the return channel, awaiting the next task assignment and entering the next work cycle. When the cumulative number of runs of the intelligent mobile sterilization unit reaches a preset threshold, the system automatically dispatches it to the automatic cleaning and maintenance docking station for maintenance.

[0068] like Figure 3As shown, to further save floor space, in one embodiment, the pretreatment docking station, sterilization docking station, and analytical docking station are all designed as a three-layer three-dimensional structure. Each station is equipped with two lifting units, which can be hydraulic lifts or chain-type lifts, and their platforms are equipped with guide rails or guide channels that dock with the mobile chassis.

[0069] The working process is as follows: When the intelligent mobile sterilization unit needs to enter the sterilization docking station, it first travels to the platform of the lifting unit. According to the instructions of the central dispatch system, the lifting unit raises the intelligent mobile sterilization unit to the predetermined floor (e.g., the second floor). Upon arrival, the powered rollers or push-pull mechanism on the platform transfers the intelligent mobile sterilization unit from the lifting unit to the track on the corresponding floor. The intelligent mobile sterilization unit then travels autonomously to a set of available passive docking interfaces on that floor for docking. After processing, the intelligent mobile sterilization unit returns to the lifting unit along the same route, then descends to the ground floor and travels to the next workstation. This three-dimensional layout greatly improves space utilization.

[0070] In summary, this invention, by creatively proposing a novel architecture of "intelligent mobile sterilization unit + functional docking station," completely overturns the traditional process flow and equipment form of ethylene oxide sterilization. It solves the core technical problems that have long plagued the field, such as large footprint, low efficiency, difficulty in expansion, poor uniformity, high energy consumption, and large fluctuations in the transfer process. It has extremely high industrial application value and broad market prospects.

[0071] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An ethylene oxide sterilization system, characterized in that, include: Multiple intelligent mobile sterilization units, each of which is a sealed chamber with autonomous movement capability, used to contain products to be sterilized; Multiple functional docking stations, including a loading docking station, a pretreatment docking station, a sterilization docking station, a desorption docking station, and an unloading docking station arranged sequentially along the operating path of the intelligent mobile sterilization unit, each of the functional docking stations being used to dock with the intelligent mobile sterilization unit and provide corresponding functional support; The intelligent scheduling and control system is communicatively connected to the intelligent mobile sterilization unit and the functional docking station, and is used to schedule the movement path and operation sequence of the intelligent mobile sterilization unit.

2. The ethylene oxide sterilization system according to claim 1, characterized in that, The intelligent mobile sterilization unit includes a cabin and a mobile chassis located at the bottom of the cabin. The cabin is equipped with an automatically opening and closing sealed door. The cabin is also equipped with multiple pretreatment interfaces, sterilization interfaces, and analysis interfaces for docking with the pretreatment docking station, sterilization docking station, and analysis docking station, respectively. The chamber is equipped with an internal environment monitoring module, including a temperature monitoring unit, a humidity monitoring unit, a gas concentration monitoring unit, and a pressure monitoring unit, which are used to monitor the sterilization environment parameters inside the chamber in real time. The cabin is equipped with an airborne controller that is electrically connected to the mobile chassis, the docking interface, and the cabin environment monitoring module, and is used to control the autonomous operation of the intelligent mobile sterilization unit.

3. The ethylene oxide sterilization system according to claim 1, characterized in that, The intelligent mobile sterilization unit is equipped with a heating and temperature control module and / or a phase change heat storage unit. The phase change heat storage unit is integrated into the wall of the cabin and is used to slowly release heat energy into the cabin after detaching from the docking station to maintain the sterilization temperature.

4. The ethylene oxide sterilization system according to claim 2, characterized in that, The cabin is also equipped with a circuit interface that docks with the functional docking station.

5. The ethylene oxide sterilization system according to claim 1, characterized in that, The pretreatment docking station, sterilization docking station, and analytical docking station are all equipped with multiple sets of passive docking interfaces. Each passive docking interface includes a main interface and a backup interface. The passive docking interface is equipped with a positioning component, an electromagnetic locking device, and a self-testing module.

6. The ethylene oxide sterilization system according to claim 1, characterized in that, The pretreatment docking station, sterilization docking station, and analytical docking station are all multi-layered structures, and each is equipped with at least one set of lifting units.

7. The ethylene oxide sterilization system according to claim 1, characterized in that, The entire sterilization docking station is a closed structure, equipped with multiple automatically opening and closing entry and exit doors, and an air circulation device. The sterilization docking station is also equipped with a leak detection sensor, an emergency spray or neutralization unit, and a multi-level safety protection unit. The entry doors, air circulation device, leak detection sensor, emergency spray or neutralization unit are all linked to the multi-level safety protection unit.

8. The ethylene oxide sterilization system according to claim 1, characterized in that, The intelligent mobile sterilization unit also includes a power supply guarantee unit, comprising: a main power supply, an auxiliary power supply, and an emergency power supply.

9. The ethylene oxide sterilization system according to claim 1, characterized in that, It also includes an automated cleaning and maintenance docking station, used for internal cleaning, drying, sealing testing and calibration of the intelligent mobile sterilization unit after it has completed multiple sterilization cycles.

10. A method for sterilizing with ethylene oxide using the system according to any one of claims 1 to 9, characterized in that, include: Step S1: At the loading docking station, the product to be sterilized is loaded into the intelligent mobile sterilization unit, and the intelligent mobile sterilization unit automatically closes the sealing door; Step S2: The intelligent mobile sterilization unit autonomously travels to the pretreatment docking station, docks with the pretreatment docking station, and performs preheating and prehumidification treatment; Step S3: After the pretreatment is completed, the intelligent mobile sterilization unit detaches from the pretreatment docking station, autonomously travels to the sterilization docking station, docks with the sterilization docking station, and introduces ethylene oxide gas for sterilization. Step S4: After sterilization is completed, the intelligent mobile sterilization unit detaches from the sterilization docking station, autonomously travels to the analysis docking station, docks with the analysis docking station, and performs ventilation analysis to reduce the residual ethylene oxide gas. Step S5: After the analysis is completed, the intelligent mobile sterilization unit autonomously travels to the unloading docking station, automatically opens the sealed door, and takes out the sterilized product; Step S6: The unloaded intelligent mobile sterilization unit travels to the loading docking station via the return channel and enters the next working cycle; In steps S2 to S4, during the movement of the intelligent mobile sterilization unit after detaching from the docking station, the temperature inside the chamber is maintained by the heat energy released by the phase change heat storage unit or the heating and temperature control module.

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