A method and apparatus for vapor cooling descaling control for water vapor for a mixed air method

Abstract

The application discloses a steam cooling and white elimination control method and device for mixed air method and for water vapor. The method is specifically as follows: a steam flow sensor measures the flow of steam, a temperature and humidity sensor measures the ambient temperature and humidity, signals are transmitted to the program of a controller, a theoretical air flow value is calculated, an air flow sensor measures the actual air flow, the controller adjusts the rotating speed of a fan, the actual air flow is adjusted to the theoretical value, and the cooling and white elimination treatment of steam is realized. The device comprises a mixing shell with two ends in communication with each other and serving as an air inlet and a mixed gas outlet respectively, a controller is installed on the mixing shell, a fan is installed at one end of the air inlet, a steam inlet pipe is arranged on the mixing shell close to the air inlet, an air flow sensor is installed between the air inlet and the steam inlet pipe, a steam flow sensor is installed on the steam inlet pipe, and a temperature sensor and a humidity sensor are arranged on the mixing shell respectively. The application realizes steam cooling and white elimination with the minimum air volume and reduces the energy consumption of the system. The device has simple structure and is easy to operate.

Description

Technical Field

[0001] This invention relates to the field of steam whitening technology, specifically to a steam cooling whitening control method and apparatus for water vapor in the mixed air method. Background Technology

[0002] The utilization of water vapor is crucial in industrial production and daily life, with the most common method being the boiling of water at atmospheric pressure. For example, household electric steamers use boiling water to generate steam for cooking. However, the use of water vapor is often accompanied by its release. If released into the atmosphere without treatment, it will condense into numerous small droplets, forming visible white plumes that cause visual pollution and corrode surrounding objects. Existing methods for eliminating white plumes using steam cooling mainly include reheating, condensation, and mixed-air cooling.

[0003] The reheat method involves heating steam or high-temperature flue gas under specific temperature and humidity conditions using both indirect and direct heat exchange. Once a certain temperature is reached, the flue gas is discharged at high altitude through an exhaust pipe, effectively eliminating white smoke. However, the reheat method requires relatively high temperatures and cannot eliminate wet plumes in winter or when temperatures are low. The condensation method involves cooling steam or high-temperature flue gas under specific temperature and humidity conditions using a cold source, condensing some of the water generated during the cooling process, and then heating it again using a heat source. Once a certain temperature is reached, the flue gas is discharged at high altitude through an exhaust stack, effectively eliminating white smoke. However, the condensation method is also limited by temperature requirements and cannot eliminate wet plumes in winter or when temperatures are low. The mixed air method has a simple structure, low cost, and wide application. Most of the fans used are fixed speed. When the ambient temperature is high and the humidity is low, the air volume requirement is low, and steam whitening can be achieved. However, excessive air volume causes additional energy consumption of the system. When the ambient temperature is low and the humidity is high, the air volume requirement is high, and the ideal whitening effect is often not achieved. Summary of the Invention

[0004] The purpose of this invention is to provide a steam cooling method and apparatus for eliminating white spots. This method can achieve steam cooling and white spot elimination with minimal airflow, reducing system energy consumption. This apparatus has a simple structure and is easy to operate.

[0005] To achieve the above objectives, the whitening method of the present invention specifically includes the following steps: S1: Opening device; S2: Monitor water vapor mass flow rate If the value is greater than 0, execute S3; otherwise, execute S7. S3: Monitor ambient temperature relative humidity of the environment Then execute S4; S4: Will and Substitute: ,get Then execute S5; S5: Monitor actual airflow (g / s), adjust the fan speed to make = Then execute S6; S6: Execute S2; S7: Close the device.

[0006] When the S1 device is turned on, a preset working time t' is set and the timer starts, with the real-time time being t0. The specific step of S6 is to determine whether the real-time time t0 is less than the preset time t'. If yes, then S2 is executed; otherwise, S7 is executed.

[0007] When device S1 is turned on, a preset monitoring period T is established, and timing begins, with the real-time time being t; device S2 monitors the water vapor mass flow rate. Let the current real-time time t be t1; the specific step of S6 is to determine whether the real-time time t is less than t1+T. If yes, then execute S5; if no, then execute S2.

[0008] The monitoring period T ranges from 5s to 15s.

[0009] The device of the present invention includes a mixing shell integrally connected to an air inlet at one end and a mixed gas outlet at the other end. A controller is installed on the mixing shell, a fan connected to the controller is installed at the air inlet end of the mixing shell, and a steam inlet pipe is provided on the mixing shell near the air inlet. An air flow sensor connected to the controller for monitoring air mass flow rate is installed between the air inlet and steam inlet pipes; a steam flow sensor connected to the controller for monitoring steam mass flow rate is installed on the steam inlet pipe; and a temperature sensor connected to the controller for monitoring ambient temperature and a humidity sensor for monitoring ambient relative humidity are installed on the mixing housing.

[0010] The mixing shell has a condensate outlet pipe on the side near the gas mixture outlet.

[0011] Compared with the prior art, the present invention has the following beneficial effects: (1) The control method of the present invention uses water vapor generated by boiling at normal pressure as the cooling object, and monitors the ambient temperature / humidity and the mass flow rate of the steam, and substitutes them into... The minimum required airflow is determined, and by controlling the airflow to the minimum value, an effective steam defoaming effect is achieved, thereby reducing the system's energy consumption.

[0012] (2) The device of the present invention has each inlet and outlet and each sensor installed in an integrally connected shell. The structure is simple. The monitoring signal of the sensor is transmitted to the controller, and the controller controls the fan to adjust the air flow to complete the cooling of steam. The operation is convenient.

[0013] Furthermore, the present invention can automatically shut down the device by setting a preset working time, saving manpower and system energy consumption. It can also reduce the computing load of the controller by setting a preset monitoring cycle, further saving system energy consumption. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the steam cooling whitening device according to an embodiment of the present invention; Figure 2 This is a flowchart of the steam cooling whitening control method according to an embodiment of the present invention; Figure 3 This is a graph showing the relationship between the minimum air-vapor mass flow rate ratio and ambient temperature and humidity when using the mixed air method to eliminate whitening of 100℃ steam under adiabatic conditions. Wherein: 1-fan; 2-mixing shell; 21-mixed gas outlet; 22-condensate outlet pipe; 23-steam inlet pipe; 24-air inlet; 3-controller; 4-temperature sensor; 5-humidity sensor; 6-air flow sensor; 7-steam flow sensor. Detailed Implementation

[0015] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0016] like Figure 1The steam cooling device shown is a steam cooling whitening control method, comprising a mixing shell 2 integrally connected to an air inlet 24 at one end and a mixed gas outlet 21 at the other end. This integral connection ensures smoother air and steam flow. The main body of the mixing shell 2 can be a square tube, a round tube, or other forms, with the specific structure determined according to actual working requirements. A controller 3 is installed on the mixing shell 2. It should be noted that the controller 3 has a timing function, allowing preset working time and monitoring cycles to save system energy. A fan 1 connected to the controller 3 is installed at one end of the air inlet 24 of the mixing shell 2. A steam inlet pipe 23 is opened on the mixing shell 2 near the air inlet 24. Proximity to the air inlet 24 allows the steam to be cooled to contact the airflow more quickly, completing the cooling process. A further connection is made between the air inlet 24 and the steam inlet 23. An air flow sensor 6, connected to controller 3, is installed to monitor air mass flow rate. Controller 3 receives sensor signals and regulates the speed of fan 1. A steam flow sensor 7, connected to controller 3, is installed on steam inlet pipe 23 to monitor steam mass flow rate. A temperature sensor 4, connected to controller 3, and a humidity sensor 5, connected to controller 3, are installed on mixing shell 2 to monitor ambient temperature and relative humidity, respectively. The data monitored by the sensors are sent to controller 3. Controller 3 obtains the minimum air flow rate from the various data and then uses a PID algorithm to control the speed of fan 1 to achieve cooling with the minimum air flow rate, saving energy. It should be noted that a condensate outlet pipe 22 is provided on the side of mixing shell 2 near the mixed gas outlet 21. The independent outlet pipe allows for better collection of condensate for subsequent treatment or reuse.

[0017] like Figure 2 The steam cooling whitening control method shown herein, and the specific steps of the above-mentioned device when using this method are as follows: S1: Turn on the device. It should be noted that the working time t' and monitoring cycle T can be preset, and the timing starts. The real time is t. Then, execute S2. The preset time is implemented by controller 3, and the monitoring cycle represented by T means that controller 3 adjusts the speed of fan 1 once in each cycle. The value range of T is 5s≤T≤15s. S2: Let the current real-time time t be t1, and then monitor the water vapor mass flow rate. Is it greater than 0? If yes, execute S3; otherwise, after the fan stops for T, execute S7. S3: Monitor ambient temperature relative humidity of the environment Then execute S4; S4: Will and Substitute: ,get Then execute S5; It should be noted that, see Figure 3 This paper presents the relationship between the minimum air-to-steam mass flow rate ratio and ambient temperature and humidity when using the mixed-air method to eliminate white plumes from 100℃ steam. It shows that the minimum flow rate ratio increases with decreasing temperature and increasing humidity. It's important to note that whether condensation occurs during the mixing of the two humid air sources can be determined using an enthalpy-humidity diagram. If the line connecting the state points of the two humid air sources on the enthalpy-humidity diagram does not intersect the saturated enthalpy-humidity curve, no condensation occurs; otherwise, condensation occurs. The process of cooling and eliminating white plumes from steam using the mixed-air method can be simplified to two mixing processes: the first is the mixing of steam and air within the mixing chamber, and the second is the mixing of the mixture after it exits the chamber with the atmosphere. The flow rate ratio of the two gases in the first mixing is controllable, while the flow rate ratio of air to the mixture in the second mixing is infinite. Clearly, in the first mixing, there exists a minimum air-to-steam mass flow rate ratio such that the mixture produced in the first mixing does not condense during its exit into the atmosphere, thus preventing the formation of white plumes. When designing a steam cooling device, if the air-to-steam flow rate ratio is always controlled to the minimum, the system energy consumption can be reduced while ensuring the white plume elimination effect. S4 provides the relationship between the minimum air vapor flow rate ratio required for whitening and air temperature and humidity. This relationship is derived from... Figure 3 The results were obtained through fitting; where temperature is in °C, relative humidity is expressed as a percentage, e is the natural constant e≈2.71828, and ln is the natural logarithm; S5: Monitors actual airflow via airflow sensor 6 (g / s), adjust the speed of fan 1 to make = Then execute S6; It should be noted that controller 3 can receive signals from temperature sensor 4, humidity sensor 5, air flow sensor 6, and steam flow sensor 7, and use PID algorithm to control the fan speed so that the actual air flow is equal to the flow calculated in S4. S6: Determine if the real-time time t is less than t1+T. If yes, execute S5; otherwise, execute S7. S7: Determine if the real-time time t is less than the preset time t'. If yes, execute S2; otherwise, execute S8. S8: Close the device.

[0018] This invention can adapt to different working environments and conditions. By monitoring steam flow and ambient temperature and humidity, the fan speed is controlled to provide a suitable air flow, thereby achieving steam cooling and de-whitening in different environments, while also reducing system energy consumption.

Claims

1. A steam cooling whitening control method for water vapor in a mixed-air method, characterized in that, Includes the following steps: S1: Opening device; S2: Monitor water vapor mass flow rate If the value is greater than 0, execute S3; otherwise, execute S7. S3: Monitor ambient temperature relative humidity of the environment Then execute S4; S4: Will and Substitute: ,get Then execute S5; S5: Monitor actual airflow (g / s), adjust the fan speed to make = Then execute S6; S6: Execute S2; S7: Close the device.

2. The steam cooling whitening control method as described in claim 1, characterized in that: When the S1 device is turned on, a preset working time t' is set and the timer starts, with the real-time time being t0. The specific step of S6 is to determine whether the real-time time t0 is less than the preset time t'. If yes, then S2 is executed; otherwise, S7 is executed.

3. The steam cooling whitening control method as described in claim 1, characterized in that: When device S1 is turned on, a preset monitoring period T is established, and timing begins, with the real-time time being t; device S2 monitors the water vapor mass flow rate. Let the current real-time time t be t1; the specific step of S6 is to determine whether the real-time time t is less than t1+T. If yes, then execute S5; if no, then execute S2.

4. The steam cooling whitening control method as described in claim 3, characterized in that: The monitoring period T ranges from 5s to 15s.

5. A steam-cooled whitening device for performing the whitening control method as described in claim 1, characterized in that: The mixture includes a mixing shell (2) with an air inlet (24) at one end and a mixed gas outlet (21) at the other end. A controller (3) is installed on the mixing shell (2). A fan (1) connected to the controller (3) is installed at one end of the air inlet (24) of the mixing shell (2). A steam inlet pipe (23) is opened on the mixing shell (2) near the air inlet (24). An air flow sensor (6) connected to the controller (3) for monitoring air mass flow rate is installed between the air inlet (24) and the steam inlet pipe (23); a steam flow sensor (7) connected to the controller (3) for monitoring steam mass flow rate is installed on the steam inlet pipe (23); and a temperature sensor (4) connected to the controller (3) for monitoring ambient temperature and a humidity sensor (5) for monitoring ambient relative humidity are also installed on the mixing housing (2).

6. The steam-cooled whitening device as described in claim 5, characterized in that: The mixing shell (2) has a condensate outlet pipe (22) on the side near the gas mixture outlet (21).

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