Electrode boiler and power calculation method

Abstract

The application discloses an electrode boiler, which comprises an outer cylinder and an inner cylinder, the inner cylinder comprises a plurality of cylindrical inner cylinders, the cylindrical inner cylinders are provided with circular electrode discs, the circular electrode discs are uniformly provided with a plurality of curved rod electrodes along the circumferences of the circular electrode discs, the centers of the circular electrode discs are connected with phase introduction electrodes, two adjacent cylindrical inner cylinders are tangentially arranged, the bottoms of the plurality of cylindrical inner cylinders are communicated and connected with an inner cylinder water inlet pipe, the bottom center of the inner cylinder is connected with an inner cylinder water outlet pipe, the outer cylinder is provided with an outer cylinder water inlet, and one end of the inner cylinder water outlet pipe is communicated with the outer cylinder water inlet. The electrode boiler can realize the uniform distribution of the voltage equipotential line between the electrode and the zero potential of the inner cylinder through the corresponding optimization design, the current density distribution is uniform, and the sharp end discharge phenomenon does not occur. In addition, the structural and position innovation design of the inner cylinder water inlet and water outlet makes the inner cylinder flow field distribution reasonable, the temperature distribution uniform and the power simple and controllable.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of boiler equipment, in particular to an electrode boiler and a power calculation method. BACKGROUND

[0002] The rapid development of electricity generation can lead to a large amount of abandoned wind and light, and how to efficiently consume renewable electricity has become a key problem to improve the utilization rate of wind and light resources. High-voltage electrode boiler is a kind of electric heat conversion equipment with high efficiency, high power density and no pollution. Its principle is to generate Joule heat by directly connecting high-voltage three-phase electric energy to a solution with certain electrical conductivity, and the hot solution transfers heat to the heat user through a heat exchanger. The existing electrode boiler is mainly divided into three types: jet type, immersion type and semi-immersed type. A high-voltage electrode boiler described in CN201711046368.1 is a jet type electrode boiler, the electrode is connected to zero potential through a jet liquid column, and the solution usually has high electrical conductivity, which can easily cause high-voltage breakdown and produce hydrogen gas; the immersion type electrode boiler uses an isolation shield to isolate the electrode immersed in the solution, which has the problem of difficult low-load operation; the semi-immersed electrode boiler separates the inner and outer cylinders, and the inner cylinder is used to heat the solution. As described in CN201922474415.3, it is a semi-immersed electrode boiler, which can realize boiler variable load operation by controlling the liquid level height in the inner cylinder. The current semi-immersed electrode boiler mainly has the problems of uneven spacing between the electrode and the inner cylinder, lack of inner cylinder flow field design, etc., which leads to uneven internal temperature field distribution. The electrical conductivity of the working medium in the electrode boiler is often positively correlated with the temperature, and the excessive local current density can cause water electrolysis, resulting in the generation of a large amount of hydrogen gas, thereby affecting the safety of the boiler. SUMMARY

[0003] 1. Technical problems to be solved by the present application

[0004] The present application aims to solve the technical problems existing in the prior art and provide an electrode boiler which can realize uniform distribution of voltage equipotential lines between the electrode and the inner cylinder zero potential, uniform distribution of current density, and no sharp end discharge phenomenon through corresponding optimization design. In addition, through the innovative design of the structure and position of the inner cylinder water inlet and outlet, the flow field distribution in the inner cylinder is reasonable, the temperature distribution is uniform, and the power is simple and controllable.

[0005] 2. Technical solutions

[0006] To solve the above problems, the technical solutions provided by the present application are as follows:

[0007] An electrode boiler comprises an outer cylinder and an inner cylinder, the inner cylinder comprises a plurality of cylindrical inner cylinders, the cylindrical inner cylinders are provided with circular electrode discs, the circular electrode discs are uniformly provided with a plurality of curved rod electrodes along the circumferential direction, the center of the circular electrode disc is connected with a phase lead-in electrode, two adjacent cylindrical inner cylinders are arranged tangentially, the bottoms of the plurality of cylindrical inner cylinders are communicated and connected with an inner cylinder water inlet pipe, the bottom center of the inner cylinder is connected with an inner cylinder water outlet pipe, the outer cylinder is provided with an outer cylinder water inlet, and one end of the inner cylinder water outlet pipe is communicated with the outer cylinder water inlet.

[0008] Optionally, the inner cylinder further comprises an inner cylinder bottom plate, the plurality of cylindrical inner cylinders are mounted on the inner cylinder bottom plate, and the edge of the inner cylinder bottom plate is inwardly recessed to form a maintenance spacing with the inner wall of the outer cylinder.

[0009] Optionally, one end of the inner cylinder water inlet pipe connected with the cylindrical inner cylinder is an insulating pipe, one end of the inner cylinder water outlet pipe connected with the outer cylinder is an insulating pipe, the outer part of the phase lead-in electrode is provided with an insulating layer, and the outer cylinder is grounded through a grounding wire.

[0010] Optionally, the bottom end of the curved rod electrode is in the shape of an umbrella handle.

[0011] Optionally, the inner cylinder is provided with an inner cylinder liquid level meter and an inner cylinder temperature meter.

[0012] Optionally, the outer cylinder is provided with an outer cylinder liquid level meter and an outer cylinder temperature meter.

[0013] Optionally, the bottom of the outer cylinder is provided with a blowdown port, a circulating water outlet and a water supply pipe, and the side edge of the outer cylinder is provided with a manhole.

[0014] Optionally, the outer cylinder is provided with an exhaust valve, a pressure regulating port and a safety valve.

[0015] Optionally, the number of the cylindrical inner cylinders is three, and the number of the curved rod electrodes on each cylindrical inner cylinder is 36.

[0016] 3, Beneficial effects

[0017] Compared with the prior art, the technical scheme provided by the present application has the following beneficial effects:

[0018] (1) The optimized design of the inner cylinder and the electrode structure of the electrode boiler makes the electric field of the inner cylinder uniformly distributed, avoids the problems of voltage breakdown due to uneven electric field in local parts and excessive local current density leading to water electrolysis to produce hydrogen, and greatly improves the safety and stability of the electrode boiler.

[0019] (2) The electrode boiler is designed based on the water power of the inner cylinder, so that the flow field distribution in the electrode boiler is more reasonable, the problems of local long-term heating without flow and local supercooling are avoided, the water supply temperature is reached, the water temperature fluctuation is small, and the heating efficiency and safety are greatly improved.

[0020] (3) The traditional electrode boiler power solving method assumes that the water conductivity is equal everywhere, and the electrode is regarded as an infinite long charged cylinder, but in the actual situation, since the temperature of the boiler water is not equal everywhere, if the water conductivity is assumed to be equal everywhere, a large error will occur in the calculation result, and the numerical simulation calculation technology method described in the present application can realize the power calculation of the electrode type hot water boiler with variable conductivity by setting the relationship between the water conductivity and the temperature change in the physical property parameters, improve the calculation accuracy, and can obtain the influence of the water conductivity and the electrode immersion depth on the power through numerical simulation calculation, and realize the power regulation of the electrode boiler.

[0021] (4) By performing numerical simulation calculation checking, the inner cylinder water temperature distribution and the electric field distribution can be obtained, and the local overheating phenomenon can be avoided, thereby improving the safety and stability of the electrode boiler. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 A structure schematic diagram of an electrode boiler according to the first embodiment of the present application is shown in the figure;

[0023] Figure 2 A schematic diagram of the electrode arrangement structure in the electrode boiler according to the first embodiment of the present application is shown in the figure;

[0024] Figure 3 A flowchart of the power calculation method of the electrode boiler according to the second embodiment of the present application is shown in the figure;

[0025] 1, outer cylinder; 2, inner cylinder; 3, cylindrical inner cylinder; 4, circular electrode disc; 5, curved rod electrode; 6, inner cylinder water inlet pipe; 7, inner cylinder water outlet pipe; 8, outer cylinder water inlet; 9, inner cylinder bottom plate; 10, insulation layer; 11, grounding wire; 12, inner cylinder liquid level meter; 13, inner cylinder temperature meter; 14, outer cylinder liquid level meter; 15, outer cylinder temperature meter; 16, blowdown outlet; 17, circulating water outlet; 18, water supply pipe; 19, manhole; 20, exhaust valve; 21, pressure regulating port; 22, safety valve; 23, phase lead-in electrode. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the present application clearer and more apparent, the present application will be further described in detail below with reference to the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and do not limit the protection scope of the present application.

[0027] It should be noted that when an element is referred to as being "fixed", "attached", "connected" or "mounted" to another element, it can be directly on the other element or intervening elements can also be present. In addition, when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements can also be present. Further, when an element is referred to as being "fixed", "attached", "connected" or "mounted" to another element, it can be fixed, attached, connected or mounted directly to the other element or intervening elements can also be present. In addition, the term "vertical" or "horizontal" as used herein is used for the purpose of explanation only and is not intended to limit the present application.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this description, the terms "therefore" and "because" are used in their conjunctive sense, meaning that the prior statement provides a reason for the subsequent statement.

[0029] The terms "first", "second", etc. are used herein only to distinguish one element from another, and do not necessarily have to appear in a specific order.

[0030] Embodiment One

[0031] The accompanying drawings are included to provide a further understanding of the application, and are incorporated in and constitute a part of this specification. It will be appreciated that the drawings are not necessarily to scale, and that, unless otherwise specifically indicated herein, elements from one drawing can be employed in another drawing without departing from the spirit and scope of the application. Figure 1 And 2The electrode boiler of the embodiment comprises an outer cylinder 1 and an inner cylinder 2, the inner cylinder 2 is arranged inside the outer cylinder 1, the inner cylinder 2 comprises a plurality of cylindrical inner cylinders 3, the cylindrical inner cylinders 3 are provided with circular electrode plates 4, each group of the cylindrical inner cylinders 3 and the circular electrode plates 4 are coaxially arranged, the edges of the circular electrode plates 4 are uniformly distributed with a plurality of curved rod electrodes 5 along the circumferential direction, the curved rod electrodes 5 are used for ensuring that the current density distribution between the circular electrode plate 16 and the cylindrical inner cylinder 18 is uniform, the heating efficiency is high, and the water temperature fluctuation is small, the curved rod electrodes 5 are fixedly connected to the circular electrode plate 4, the curved rod electrodes 5 are in a cylindrical curved rod shape, the center of the circular electrode plate 4 is connected with a phase lead-in electrode 23, two adjacent cylindrical inner cylinders 3 are tangentially arranged, the tangential arrangement between the cylindrical inner cylinders 3 can effectively control the spacing between the electrode and the inner cylinder arrangement, and the uniformity is maintained, the bottoms of a plurality of the cylindrical inner cylinders 3 are communicated and connected with an inner cylinder water inlet pipe 6, specifically, one end of the inner cylinder water inlet pipe 6 is communicated with the bottoms of a plurality of the cylindrical inner cylinders 3 through a plurality of branch pipes, the branch pipes are respectively communicated into the bottoms of the corresponding cylindrical inner cylinders 3, the outlet heights of the branch pipes are flush with the bottom ends of the curved rod electrodes 5, the bottom center of the inner cylinder 2 is connected with an inner cylinder water outlet pipe 7, the outer cylinder 1 is provided with an outer cylinder water inlet 8, one end of the inner cylinder water outlet pipe 7 is communicated with the outer cylinder water inlet 8, the purpose of arranging the outer cylinder water inlet 8 is to guide the hot water heated to the target temperature to the outer cylinder 1 through the inner cylinder water outlet pipe 7, the bottoms of a plurality of the cylindrical inner cylinders 3 are communicated, which is used for ensuring that the heights of the boiler water in the cylindrical inner cylinders 18 are consistent, ensuring that the resistances between the phases are equal, the three cylindrical inner cylinders 18 are equipotential, thereby ensuring that the inner cylinder water outlet temperature fluctuation is small, and preventing the potential deviation of three-phase electricity from causing tripping.

[0032] The electrode boiler can realize uniform distribution of voltage equipotential lines between the electrode and the inner cylinder with zero potential, uniform distribution of current density, and no sharp end discharge phenomenon, in addition, the structure and position of the inner cylinder water inlet and the water outlet are innovatively designed, so that the flow field distribution in the inner cylinder is reasonable, the temperature distribution is uniform, and the power is simple and controllable.

[0033] As an optional solution of the present application, the inner cylinder 2 further comprises an inner cylinder bottom plate 9, the material of the inner cylinder bottom plate 9 is preferably alloy steel, a plurality of the cylindrical inner cylinders 3 are installed on the inner cylinder bottom plate 9, the edge of the inner cylinder bottom plate 9 is concave, the edge of the inner cylinder bottom plate 9 is inwardly recessed to form a maintenance spacing with the inner wall of the outer cylinder 1, the maintenance spacing is greater than 55 cm, so as to ensure that the maintenance personnel have enough space to enter the inner cylinder to work.

[0034] As an optional solution of the present application, the end of the inner cylinder water inlet pipe 6 connected with the cylindrical inner cylinder 3 is an insulating pipe, the end of the inner cylinder water outlet pipe 7 connected with the outer cylinder 1 is an insulating pipe, the pipes are connected by flanges, the external part of the phase lead-in electrode 23 is provided with an insulating layer 10, the insulating layer is an insulating sleeve, and the outer cylinder 1 is grounded through a grounding wire 11, so as to prevent the inner cylinder branch pipe lower end, the inner cylinder water outlet pipe upper end and the outer cylinder from being electrified, so as to prevent electric shock, and the material of the above insulating parts is preferably polytetrafluoroethylene.

[0035] As an optional solution of the present application, the bottom end of the curved rod electrode 5 is in the shape of an umbrella handle, so as to prevent the tip from discharging and causing water to break down to generate hydrogen, thereby being not conducive to the stable operation of the electrode boiler.

[0036] As an optional solution of the present application, the inner cylinder 2 is provided with an inner cylinder liquid level meter 12 and an inner cylinder temperature meter 13, the inner cylinder liquid level meter 12 is used to detect the height of the inner cylinder liquid level, so as to facilitate the power adjustment of the electrode boiler by adjusting the liquid level height, and the inner cylinder temperature meter 13 is used to detect the temperature of the inner cylinder.

[0037] As an optional solution of the present application, the outer cylinder 1 is provided with an outer cylinder liquid level meter 14 and an outer cylinder temperature meter 15, the outer cylinder liquid level meter 14 is used to detect the height of the outer cylinder liquid level, and the outer cylinder temperature meter 15 is used to detect the temperature of the outer cylinder.

[0038] As an optional solution of the present application, the bottom of the outer cylinder 1 is provided with a blowdown port 16, a circulating water outlet 17 and a water supply pipe 18, and the side of the outer cylinder 1 is provided with a manhole 19, the purpose of arranging the blowdown port 16 is to timely remove the impurities deposited at the bottom of the outer cylinder 1, and to timely drain the boiler water when the boiler is stopped for maintenance; the purpose of arranging the circulating water outlet 17 is to send the hot water with a certain temperature in the outer cylinder 1 into an external heat exchange equipment, and the cooled boiler water is sent into the inner cylinder through the inner cylinder water inlet pipe 6 to complete the heating process of the boiler water in the inner cylinder 2; and the purpose of arranging the manhole 19 is that the maintenance personnel can enter the electrode boiler for maintenance and replace the curved rod electrode 5 through the manhole 19 when the electrode boiler is maintained.

[0039] As an optional solution of the present application, the outer cylinder 1 is provided with an exhaust valve 20, a pressure regulating port 21 and a safety valve 22, the working pressure of the boiler is preferably 1 MPa, the purpose of arranging the exhaust valve 20 is to periodically discharge a small amount of impurity gas in the electrode boiler; the purpose of arranging the pressure regulating port 21 is to raise the electrode boiler to a certain pressure for operation; and the purpose of arranging the safety valve 22 is to prevent the electrode boiler from overpressure, so as to ensure the safe and stable operation of the electrode boiler.

[0040] As an optional solution of the present application, the phase introduction electrode 23 is connected with the outer cylinder 1 through a flange, the phase introduction electrode 23 adopts a star connection, and the material is preferably copper. The bottom end of the phase introduction electrode 23 is fixed in the center of the circular electrode disc 4 through a nut, and the inner cylinder is connected to zero potential. The external voltage of the phase introduction electrode 23 is 0-10 kV.

[0041] Embodiment two

[0042] In combination with the accompanying drawings, Figure 3 , the power calculation method of the electrode boiler is characterized by comprising the following steps: S1: taking the inner cylinder of the electrode boiler as a prototype, establishing a geometric model of the inner cylinder boiler water according to different electrode immersion depths, and dividing the grid; S2: importing the drawn grid into a numerical simulation software, checking the grid and adjusting the size ratio of the grid; S3: selecting a solver and a solving method; S4: calculating the potential distribution through a potential equation, and calculating the corresponding Joule heat. The calculated Joule heat is added to the energy equation, and the numerical simulation process of the power heating is realized through direct coupling; S5: specifying the boundary conditions and the physical properties of the materials; S6: initializing the flow field and starting the iterative solving process until the calculation converges; S7: post-processing the calculation results to check the temperature field and whether there is an over-temperature phenomenon. If there is an over-temperature phenomenon, the inlet flow is increased and the calculation is returned to S5 until there is no over-temperature phenomenon, and the next step of calculation is performed; S8: whether the power of the electrode boiler calculated by the numerical simulation meets the design power. If it does not meet the design power, the electrode immersion depth and the solution conductivity are changed, and the calculation is returned to S1 until the design power is met, and the next step of processing is performed; S9: outputting the power of the electrode boiler and post-processing the calculation results.

[0043] In S4, when the numerical simulation is calculated, the potential model is opened, the potential distribution is calculated through the potential equation , wherein, is the potential, and sigma is the conductivity. S is the potential source term; the Joule heat generated after the current flows through the fluid can be calculated by . The calculated Joule heat S h1 is substituted into the S h term of the energy equation , wherein, k eff is the effective thermal conductivity, and the right side of the equation is the heat conduction term, the viscous dissipation term and the source term. The numerical simulation process of the power heating is realized through direct coupling.

[0044] The relationship between the conductivity and the temperature of the electrode boiler water is determined by experiment and input into the numerical simulation software for calculation.

[0045] The traditional electrode boiler power solving method assumes that the water conductivity is equal everywhere and the electrode is regarded as an infinite long charged cylinder, but in the actual situation, the temperature of the boiler water is not equal everywhere, and if the water conductivity is assumed to be equal everywhere, a large error will be caused in the calculation result. The numerical simulation calculation technology method described in the present application can realize the electrode type hot water boiler power calculation of the variable conductivity by setting the relationship between the water conductivity and the temperature change in the physical property parameters, improve the calculation accuracy, and can obtain the influence of the water conductivity and the electrode immersion depth on the power through the numerical simulation calculation, and realize the power regulation and control of the electrode boiler.

[0046] Through the numerical simulation calculation check, the inner cylinder boiler water temperature distribution and the electric field distribution can be obtained, the local overheating phenomenon can be avoided, and the safety and stability of the electrode boiler are improved.

[0047] The above describes the present application and its embodiments in a schematic manner, and the description is not restrictive, and the shown in the drawings is only one of the embodiments of the present application, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired thereby, without departing from the purpose of the present application, similar structure modes and embodiments can be designed without creativity, which shall belong to the protection scope of the present application.

Claims

1. An electrode boiler, characterized in that: The device includes an outer cylinder and an inner cylinder. The inner cylinder comprises several cylindrical inner cylinders, each with a circular electrode disk. Several curved rod electrodes are evenly distributed along the circumference of the circular electrode disk. A phase-introducing electrode is connected to the center of the circular electrode disk. Two adjacent cylindrical inner cylinders are arranged tangentially. The bottoms of the cylindrical inner cylinders are connected to each other and connected to the inner cylinder water inlet pipe. An inner cylinder drain pipe is connected to the center of the bottom of the inner cylinder. The outer cylinder has an outer cylinder water inlet, and one end of the inner cylinder drain pipe is connected to the outer cylinder water inlet.

2. An electrode boiler according to claim 1, characterized in that: The inner cylinder also includes an inner cylinder bottom plate, and several of the cylindrical inner cylinders are installed on the inner cylinder bottom plate. The edge of the inner cylinder bottom plate is recessed inward to form a maintenance gap with the inner wall of the outer cylinder.

3. An electrode boiler according to claim 1, characterized in that: The end of the inner cylinder water inlet pipe connected to the cylindrical inner cylinder is an insulating pipe, the end of the inner cylinder water outlet pipe connected to the outer cylinder is an insulating pipe, the outer side of the phase introduction electrode is provided with an insulating layer, and the outer cylinder is grounded through a grounding wire.

4. An electrode boiler according to claim 1, characterized in that: The bottom end of the curved electrode is shaped like an umbrella handle.

5. An electrode boiler according to claim 1, characterized in that: The inner cylinder is equipped with an inner cylinder level gauge and an inner cylinder thermometer.

6. An electrode boiler according to claim 1, characterized in that: The outer cylinder is equipped with an outer cylinder level gauge and an outer cylinder thermometer.

7. An electrode boiler according to claim 1, characterized in that: The bottom of the outer cylinder is provided with a drain outlet, a circulating water outlet and a water supply pipe, and the side of the outer cylinder is provided with a manhole.

8. An electrode boiler according to claim 1, characterized in that: The outer cylinder is equipped with an exhaust valve, a pressure regulating port, and a safety valve.

9. A method for calculating the power of an electrode boiler, characterized in that: Includes the following steps, S1: Using the electrode boiler described in claim 1 as a prototype, establish a geometric model of the inner cylinder boiler water according to different electrode immersion depths, and divide it into grids; S2: Import the completed mesh into the numerical simulation software, check the mesh, and adjust the mesh size scale; S3: Select the solver and solution method; S4: Calculate the potential distribution through the potential equation and the corresponding Joule heat. Add the calculated Joule heat to the energy equation and realize the numerical simulation process of electric heating through direct coupling. S5: Specify boundary conditions and material physical properties; S6: Initialize the flow field and begin the iterative solution process until the calculation converges; S7: Post-process the calculation results to check the temperature field and see if there is any over-temperature phenomenon. If there is an over-temperature phenomenon, increase the inlet flow rate and return to S5 for calculation until there is no over-temperature phenomenon, and then proceed to the next calculation. S8: Check whether the electrode boiler power obtained by numerical simulation meets the design power. If it does not meet the design power, change the electrode immersion depth and solution conductivity, return to S1 for calculation, until the design power is met, and proceed to the next step. S9: Output electrode boiler power and perform post-processing of calculation results.

10. The power calculation method for an electrode boiler according to claim 9, characterized in that: In S4, during numerical simulation calculations, the potential model is enabled, and the potential equations are used... Calculate the potential distribution, where, Let σ be the electric potential, σ be the conductivity, and S be the potential source term; the Joule heat generated when current flows through a fluid can be obtained from... Calculation, by obtaining the Joule heat S h1 Substitute into the energy equation S h In the term, where k eff The effective thermal conductivity.

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