Power-on device and method for electroosmosis dehydration of soil body containing series-parallel power supply

Abstract

The invention relates to the technical field of soil electro-osmosis dehydration, and particularly discloses a series-parallel power supply-containing electrifying device and method for soil electro-osmosis dehydration, the device comprises a power supply, a plurality of current distributors and a plurality of electrode groups, and the power supply comprises a plurality of power supply modules with adjustable series-parallel states; the method comprises the steps of device preparation; single-round electrifying: applying initial voltage to each electrode group through a current distributor, detecting the current of each group, and controlling the on-off of the current of the group or adjusting the voltage of the group through the current distributor according to the detected current of each group; and step-by-step boosting and multi-turn electrifying are performed. The on-off of the current is controlled and the voltage is adjusted according to the change of the current along with time in the electroosmosis process, so that the electroosmosis is always carried out under a proper voltage condition, the electroosmosis efficiency is improved, and the waste of electric energy is reduced; by adjusting the series-parallel connection state of the plurality of power supply modules, different current and voltage requirements can be met in different stages of electrification, and the design power of the power supply can be reduced.

Description

Technical Field

[0001] The present application relates to the technical field of soil electroosmosis dehydration, and in particular to a power supply device and method for soil electroosmosis dehydration comprising series-parallel power supplies. Background Art

[0002] There are five main electrical phenomena in soil, namely: flow potential, migration potential, electroosmosis, ion migration and electrophoresis. The soil electrokinetic technology developed by using soil electrical phenomena is a platform technology that realizes water migration, ion migration, electrochemical reaction, etc. in the soil by passing direct current into the soil. This technology can be applied to many fields, such as: sludge dehydration, soft foundation treatment, contaminated soil remediation, mud and water co-control, saline-alkali land control, rare earth green mining, etc.

[0003] For special soils such as mud ponds, tidal flats, and river channels, electroosmosis is an effective dehydration method because the soil particles are small and the permeability coefficient is low, making it difficult for pore water to seep out naturally. Electroosmosis dehydration technology is to place the water-containing soil under the action of an electric field. In a system where the movement of solids is restricted, the counterions in the diffusion layer move toward the electrode along the slip interface, while driving water molecules to move toward the negative electrode. Water is discharged from the negative electrode by suction or gravity drainage to achieve soil precipitation.

[0004] In the initial stage of power-on, the soil has high water content, low resistance and high current. As power-on progresses, the soil water content decreases, the ion content in the pore water decreases, and the soil near the electrode polarizes, causing the current to increase. Most of the current electroosmosis dehydration technologies use ordinary transformer and rectifier power supplies. The main problems are: (1) Due to the uneven nature of the soil on site, the current changes differently over time. If the same power-on method is used for each area, it is difficult to produce the expected effect when the inappropriate current and voltage are used in the invalid power-on area, and electric energy is wasted. (2) When applied on a large scale, the power and energy consumption are too high, which restricts the large-scale application of soil electroosmosis dehydration technology.

[0005] On the other hand, the design power of the power supply is usually designed based on the maximum current and maximum voltage. However, in soil electrodynamic technology applications, in the initial stage of power-on, the soil resistance is small, and high current corresponds to low voltage; as power-on progresses, the soil resistance increases, and high voltage corresponds to low current. If different current and voltage requirements need to be met at different stages of power-on, the power supply needs a larger design power, which increases the cost of the power supply. Summary of the invention

[0006] In order to improve electroosmosis efficiency, reduce power consumption, and reduce the design power of a power supply, the present application provides a power supply device and method for electroosmosis dehydration of soil comprising series-parallel power supplies.

[0007] The present application provides a method for applying electricity to soil electroosmotic dehydration including series-parallel power supplies, which adopts the following technical solution: A method for applying electricity to soil electroosmotic dehydration comprising a series-parallel power supply, comprising the following steps: Device preparation: Divide the site to be treated into several areas, bury an electrode group in the soil of each area, each electrode group includes several positive electrode columns and several negative electrode columns; set a current distributor in each area, connect the positive electrode column and negative electrode column in each electrode group to the positive electrode and negative electrode of the current distributor in this area respectively; connect the current distributor to a power supply, the power supply includes multiple power modules, and the series and parallel states between the multiple power modules can be adjusted; Single-round energization: Apply a starting voltage to each electrode group through a current distributor and detect the current of each group. According to the magnitude of the detected current of each group, the current distributor is used to control the current on and off of the group or adjust the magnitude of the voltage of the group. Step-by-step boost and multiple rounds of power-on: During a single round of power-on, the data of the change of current over time in each group is fitted to obtain the fitting curve I=Ae -at +B, where I is the current, t is the power-on time, A is the coefficient, a is the time index, B is the current margin constant, and e is the natural constant; when the current detection value approaches B, the power-on of the group is ended, and then the next round of power-on is carried out, and the starting voltage of the latter round of power-on is higher than the starting voltage of the previous round of power-on; before each round of power-on, the series and parallel states of multiple power modules in the power supply are changed to make the output voltage of the power supply increase round by round.

[0008] Furthermore, the single-round power-on step includes: If the detected current is greater than the set upper limit of the current of a single group, the power supply of the group will be stopped; If the detected current is not greater than the set single group current upper limit, it is determined whether the detected current is less than the set single group current lower limit, and the group voltage is then adjusted.

[0009] Furthermore, the single-wheel power-on step further includes: If the detected current is less than the set single group current lower limit, the voltage of the group is increased gradually until the current reaches the set single group current lower limit, and the current voltage is maintained to continue powering on; If the detected current is not less than the set lower limit of the single group current, it is determined whether the voltage is on an upward trend, and the voltage of the group is further adjusted.

[0010] Furthermore, the single-wheel power-on step further includes: If the detected current is not less than the set single group current lower limit and the voltage is on the rise, the voltage of the group is reduced and the power is continued; If the detected current is not less than the set single group current lower limit and the voltage does not show an upward trend, the current voltage is maintained and power is supplied.

[0011] Furthermore, the single-round power-on step also includes: applying a starting voltage to the non-connected group and detecting the current at regular intervals, and controlling the group to connect or keep the group disconnected through a current distributor according to the magnitude of the detected current.

[0012] Furthermore, the single-round power-on step also includes: when the total current of all groups is less than the set total current upper limit, applying a starting voltage to the non-connected group and detecting the current, and according to the size of the detected current, controlling the group to connect or keep the group disconnected through the current distributor.

[0013] Furthermore, after each round of energization is completed, the positive and negative poles of the current distributor are short-circuited to release the charge; while one or more groups are releasing the charge, the other groups are kept energized.

[0014] Furthermore, after each short circuit is completed, the polarity of the electrodes is switched before the next round of power-on is performed.

[0015] Furthermore, during the first round of power-on, multiple power modules are all connected in parallel, so that the power supply outputs low voltage and high current; as the number of power-on rounds increases, the number of parallel power modules is reduced and the number of series power modules is increased, so that the output voltage of the power supply increases round by round.

[0016] The present application also discloses a power supply device for soil electroosmotic dehydration comprising a series-parallel power supply, which is used to implement the above-mentioned power supply method for soil electroosmotic dehydration comprising a series-parallel power supply, and the device comprises: A power supply, comprising a plurality of power modules, wherein the series and parallel connection states between the plurality of power modules can be adjusted; A plurality of electrode groups are respectively buried in soil bodies in different areas of the site to be treated, each electrode group includes a plurality of positive electrode columns and a plurality of negative electrode columns, the positive electrode columns include a plurality of positive electrode rods arranged in columns, the negative electrode columns include a plurality of negative electrode rods arranged in columns, and the positive electrode columns and negative electrode columns in each electrode group are arranged alternately; A plurality of current distributors corresponding to a plurality of electrode groups one by one, in each electrode group, the positive electrode column and the negative electrode column are respectively connected to the positive electrode and the negative electrode of the current distributor; the current distributor is connected to a power supply to adjust the voltage applied to the corresponding electrode group; the current distributor also has a power-on parameter reading back function, a polarity conversion function, a short-circuit function and a disconnection function; The controller is used to control the on / off and voltage regulation of the corresponding current distributor according to the current conditions in each area, and to change the series and parallel connection status between multiple power modules to adjust the output voltage and current of the power supply.

[0017] In summary, the present application includes at least one of the following beneficial technical effects: 1. The present application controls the on-off of the current and adjusts the voltage according to the change of the current over time during the electroosmosis process, so as to keep the electroosmosis always under appropriate voltage conditions, improve the electroosmosis efficiency, reduce the waste of electric energy, and help reduce energy consumption; 2. This application divides the site to be treated into several areas for separate control, which is conducive to overcoming the regional differences caused by the uneven properties of the soil, ensuring that each area can implement electroosmosis under appropriate voltage conditions, thereby improving electroosmosis efficiency and reducing energy waste; 3. Through the short-circuit discharge process, the electrode polarization in the soil is eliminated, thereby enhancing the electroosmosis effect and reducing energy consumption; at the same time, the short-circuit discharge time is fully utilized to energize other areas, thereby reducing the demand for power supply; 4. Through the series-parallel combination of multiple power modules, in the initial stage of power-on, the parallel method is adopted to meet the high current demand; in the later stage of power-on, as the soil resistance gradually increases, the series method is adopted to meet the high voltage demand, and the use of power modules with lower design power can meet different current and voltage requirements at different stages of power-on. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of an energizing device for soil electroosmotic dehydration including a series-parallel power supply according to an embodiment of the present application; Figure 2 It is a flow chart of a single round of power-on in a power-on method for electroosmotic dehydration of soil comprising a series-parallel power supply in an embodiment of the present application; Figure 3 It is one of the flow charts of connecting a non-connected group during a single round of power-on in a power-on method for electro-osmotic dehydration of soil including a series-parallel power supply in an embodiment of the present application; Figure 4 This is the second flowchart of connecting the non-connected groups during a single round of power-on in a power-on method for electro-osmotic dehydration of soil that includes series-parallel power supplies in an embodiment of the present application.

[0019] Figure numerals: 1, power supply; 1-1, power supply module; 2, current distributor; 3, electrode group; 3-1, positive electrode array; 3-2, negative electrode array. DETAILED DESCRIPTION

[0020] The following is combined with Figure 1-4 This application is described in further detail.

[0021] The present application embodiment discloses a power supply device for soil electroosmotic dehydration comprising a series-parallel power supply. Figure 1The power supply device for soil electroosmotic dehydration including series-parallel power supplies includes a power supply 1, a plurality of electrode groups 3, and a plurality of current distributors 2 corresponding to the plurality of electrode groups 3. The power supply 1 includes a plurality of power modules 1-1, and the series-parallel states between the plurality of power modules 1-1 can be adjusted.

[0022] Reference Figure 1 The site to be treated is divided into three areas, and three electrode groups 3 are buried in the three areas respectively. Each electrode group 3 includes a number of positive electrode columns 3-1 and a number of negative electrode columns 3-2. Each positive electrode column 3-1 is formed by connecting a plurality of positive electrode rods arranged in columns at intervals through wires, and the distance between two adjacent positive electrode rods is 1m; each negative electrode column 3-2 is formed by connecting a plurality of negative electrode rods arranged in columns at intervals through wires, and the distance between two adjacent negative electrode rods is 1m. The positive electrode columns 3-1 and negative electrode columns 3-2 in each electrode group 3 are arranged alternately at intervals, and the interval is set to 1m.

[0023] Reference Figure 1 In each electrode group 3, the positive electrode column 3-1 and the negative electrode column 3-2 are respectively connected to the positive electrode and the negative electrode of the current distributor 2 through the connector; the current distributor 2 is connected to the power supply 1 to adjust the voltage applied to the corresponding electrode group 3. The current distributor 2 also has the function of reading back the power-on parameters (current, voltage, etc.), polarity conversion function, short-circuit function and disconnection function.

[0024] The device also includes a controller for controlling the on / off and voltage regulation of the corresponding current distributor 2 according to the current conditions in each area, and for changing the series and parallel states between multiple power modules 1-1 to adjust the output voltage and current of the power supply 1.

[0025] A method for energizing a soil body for electroosmotic dehydration is implemented by using the above-mentioned energizing device for soil body electroosmotic dehydration comprising a series-parallel power supply, comprising the following steps: Step 1: Device preparation: The site to be treated is divided into three areas, and an electrode group 3 is buried in the soil of each area, each electrode group 3 includes a plurality of positive electrode arrays 3-1 and a plurality of negative electrode arrays 3-2; a current distributor 2 is set in each area, and the positive electrode array 3-1 and the negative electrode array 3-2 in each electrode group 3 are respectively connected to the positive pole and the negative pole of the current distributor 2 in this area; the current distributor 2 is connected to the power supply 1.

[0026] Step 2: Single wheel power on: The current distributor 2 applies a starting voltage (e.g., 2V) to each electrode group 3 and detects the current of each group. According to the magnitude of the detected current of each group, the current distributor 2 controls the current on and off of the group or adjusts the magnitude of the voltage of the group. Figure 2 , specifically including the following steps: Step 2.1: After applying the starting voltage, if the detected current is greater than the set upper limit of the current of a single group (for example, 60A), the power supply of the group is stopped.

[0027] Step 2.2: After applying the starting voltage, if the detection current is not greater than the set single group current upper limit (60A), it is determined whether the detection current is less than the set single group current lower limit (e.g. 50A), and then the group voltage is adjusted, which specifically includes the following steps: Step 2.2.1: If the detected current is less than the set single group current lower limit (50A), the voltage of the group is gradually increased (for example, in steps of 2V) until the current reaches the set single group current lower limit (50A), and then the current voltage is maintained to continue powering on.

[0028] Step 2.2.2: If the detected current is not less than the set single group current lower limit (50A), determine whether the voltage is on an upward trend, and then further adjust the group voltage, which specifically includes the following steps: Step 2.2.2.1: If the detected current is not less than the set single group current lower limit (50A) and the voltage is on an upward trend, reduce the voltage of the group and continue to power on.

[0029] Step 2.2.2.2: If the detected current is not less than the set single-group current lower limit (50A) and the voltage does not show an upward trend, maintain the current voltage and continue to power on.

[0030] Step 2.3: Reference Figure 3 , at regular intervals (for example, every hour), a starting voltage is applied to the non-connected group and the current is detected. According to the magnitude of the detected current, the current distributor 2 controls the group to be connected or keeps the group disconnected, specifically including the following steps: Step 2.3.1: If the current of the non-connected group is less than the set single group current lower limit (50A), determine whether the total current of all groups is less than the set total current upper limit (e.g. 400A). If so, connect the group; if not, keep the group disconnected.

[0031] Step 2.3.2: If the current of the non-connected group is not less than the set single group current lower limit (50A), keep the group disconnected.

[0032] Step 2.4: Reference Figure 4 , read the total current value of all groups in real time. When the total current value of all groups is less than the set upper limit of the total current (400A), apply the starting voltage to the group that is not connected and detect the current. According to the size of the detected current, control the group to connect or keep the group disconnected through the current distributor. Specifically, the following steps are included: Step 2.4.1: If the current of the unconnected group is less than the set single group current lower limit (50A), determine whether the total current of all groups is less than the set total current upper limit (400A). If so, connect the group; if not, keep the group disconnected.

[0033] Step 2.4.2: If the current of the disconnected group is not less than the set single group current lower limit (50A), keep the group disconnected.

[0034] Step 3: Step-by-step voltage boost and multiple rounds of power-on: During a single round of power-on, the data of the change of current over time in each group is fitted to obtain the fitting curve I=Ae -at +B, where I is the current, t is the power-on time, A is the coefficient, a is the time index, B is the current margin constant, and e is the natural constant.

[0035] When the current detection value approaches B, the round of energization of the area is terminated, and the positive and negative electrodes of the current distributor 2 are short-circuited to release the charge. During the period when one or more groups release the charge, the other groups are kept energized, so that the power left by the discharged groups is distributed to other areas to maximize the use of the power supply.

[0036] When the current generated by the released charge is close to zero, the polarity of the current distributor 2 is switched, and the original positive electrode array 3-1 is switched to the negative electrode array 3-2, and the original negative electrode array 3-2 is switched to the positive electrode array 3-1. The purpose of switching polarity is that as the electroosmosis proceeds, the positive electrode area becomes dry and the humidity of the negative electrode area increases. Switching the polarity of the electrode makes the original dry area moist, thereby reducing the resistance and increasing the effective electric field strength of the soil, which is beneficial to improving the electroosmosis efficiency.

[0037] After the polarity conversion is completed, the next round of power-on is carried out on the area. The starting voltage of the next round of power-on is higher than the starting voltage of the previous round of power-on. The starting voltages of multiple rounds of power-on are set to 2V, 10V, 20V, 40V, 60V, 80V, etc. The method of each round of power-on is the same as step 2.

[0038] As the number of power-on rounds increases, the number of parallel power modules is reduced, and the number of series power modules is increased. For example, power supply 1 includes four power modules 1-1, and the maximum design voltage / current of each power module 1-1 is 20V / 100A. At the beginning of power-on, when the starting voltage is not higher than 20V, all four power modules 1-1 are connected in parallel to meet the requirements of low voltage and high current (400A) at the beginning of power-on. As the number of power-on rounds increases, the starting voltage increases. When the starting voltage is 40V, the four power modules 1-1 are connected in series in pairs and then in parallel to meet the requirements of medium current (200A) in the middle of power-on. When the starting voltage is 60V, three of the power modules 1-1 are connected in series. When the starting voltage is 80V, four power modules 1-1 are connected in series to provide high voltage and low current (100A). It should be noted that during each round of power-on, the current flowing through each power module 1-1 cannot exceed its maximum design current value.

[0039] If a conventional power supply that meets high current (400A) and high voltage (80V) is used, the power is 400A×80V=32kW. This embodiment uses a combination of four power modules, and the total power of the power is 4×20V×100A=8kW, which is only 1 / 4 of the conventional power supply.

[0040] This embodiment divides the site to be treated into several areas for separate control, which is conducive to overcoming the regional differences caused by the uneven properties of the soil and ensuring that each area can implement electroosmosis under appropriate voltage conditions. Specifically, according to the change of current over time during the electroosmosis process, the on-off of the current is controlled and the voltage is adjusted to keep the electroosmosis always under appropriate voltage conditions, improve the electroosmosis efficiency, reduce the waste of electric energy, and help reduce energy consumption. Using the power-on method provided in this application, the power consumption per unit volume is about 0.5 degrees / m 3 The traditional method of using ordinary transformer and rectifier power supply consumes about 10 kWh / m 3 , or even higher.

[0041] It should be noted that the power-on method and power-on device provided in this application can not only be applied to soil electro-osmosis dehydration, but also can be applied to other soil electric technologies, such as saline-alkali land management, contaminated soil remediation, rare earth electric mining, etc., to achieve the effect of reducing energy consumption.

[0042] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for applying electricity to soil electroosmotic dehydration comprising a series-parallel power supply, characterized in that: The following steps are involved: Device preparation: Divide the site to be treated into several areas, bury an electrode group in the soil of each area, each electrode group includes several positive electrode columns and several negative electrode columns; set a current distributor in each area, connect the positive electrode column and negative electrode column in each electrode group to the positive electrode and negative electrode of the current distributor in this area respectively; connect the current distributor to a power supply, the power supply includes multiple power modules, and the series and parallel states between the multiple power modules can be adjusted; Single-round energization: Apply a starting voltage to each electrode group through a current distributor and detect the current of each group. According to the magnitude of the detected current of each group, the current distributor is used to control the current on and off of the group or adjust the magnitude of the voltage of the group. Step-by-step boost and multiple rounds of power-on: During a single round of power-on, the data of the change of current over time in each group is fitted to obtain the fitting curve I=Ae -at +B, where I is the current, t is the power-on time, A is the coefficient, a is the time index, B is the current margin constant, and e is the natural constant; when the current detection value approaches B, the power-on of the group is ended, and then the next round of power-on is carried out, and the starting voltage of the latter round of power-on is higher than the starting voltage of the previous round of power-on; before each round of power-on, the series and parallel states of multiple power modules in the power supply are changed to make the output voltage of the power supply increase round by round.

2. The method for applying electricity to soil electroosmotic dehydration comprising series-parallel power supplies according to claim 1, characterized in that: The single-round power-on steps include: If the detected current is greater than the set upper limit of the current of a single group, the power supply of the group will be stopped; If the detected current is not greater than the set single group current upper limit, it is determined whether the detected current is less than the set single group current lower limit, and the group voltage is then adjusted.

3. The method for applying electricity to soil electroosmotic dehydration comprising series-parallel power supplies according to claim 2, characterized in that: The single-round power-on steps also include: If the detected current is less than the set single group current lower limit, the voltage of the group is increased gradually until the current reaches the set single group current lower limit, and the current voltage is maintained to continue powering on; If the detected current is not less than the set lower limit of the single group current, it is determined whether the voltage is on an upward trend, and the voltage of the group is further adjusted.

4. The method for applying electricity to soil electroosmotic dehydration comprising series-parallel power supplies according to claim 3, characterized in that: The single-round power-on steps also include: If the detected current is not less than the set single group current lower limit and the voltage is on the rise, the voltage of the group is reduced and the power is continued; If the detected current is not less than the set single group current lower limit and the voltage does not show an upward trend, the current voltage is maintained and power is supplied.

5. The method for applying electricity to soil electroosmotic dehydration comprising series-parallel power supplies according to claim 2, characterized in that: The single-round power-on step also includes: applying a starting voltage to the non-connected group and detecting the current at regular intervals, and controlling the group to connect or keep the group non-connected according to the size of the detected current through the current distributor.

6. The method for applying electricity to soil electroosmotic dehydration comprising series-parallel power supplies according to claim 2, characterized in that: The single-round power-on step also includes: when the total current of all groups is less than the set total current upper limit, applying a starting voltage to the non-connected group and detecting the current, and according to the size of the detected current, controlling the group to connect or keep the group disconnected through the current distributor.

7. The method for applying electricity to soil electroosmotic dehydration comprising series-parallel power supplies according to claim 1, characterized in that: After each round of energization, the positive and negative poles of the current distributor are short-circuited to release the charge; while one or more groups are releasing the charge, the other groups remain energized.

8. The method for applying electricity to soil electroosmotic dehydration comprising series-parallel power supplies according to claim 7, characterized in that: After each short circuit, the polarity of the electrodes is reversed before the next round of power-on.

9. The method for applying electricity to soil electroosmotic dehydration comprising series-parallel power supplies according to claim 1, characterized in that: During the first round of power-on, multiple power modules are connected in parallel, so that the power supply outputs low voltage and high current; as the number of power-on rounds increases, the number of parallel power modules is reduced and the number of series power modules is increased, so that the output voltage of the power supply increases with each round.

10. A power supply device for soil electroosmosis dehydration comprising a series-parallel power supply, characterized in that: The device for implementing the method for electroosmotic dehydration of soil comprising series-parallel power supplies as claimed in any one of claims 1 to 9 comprises: A power supply, comprising a plurality of power modules, wherein the series and parallel connection states between the plurality of power modules can be adjusted; A plurality of electrode groups are respectively buried in soil bodies in different areas of the site to be treated, each electrode group includes a plurality of positive electrode columns and a plurality of negative electrode columns, the positive electrode columns include a plurality of positive electrode rods arranged in columns, the negative electrode columns include a plurality of negative electrode rods arranged in columns, and the positive electrode columns and negative electrode columns in each electrode group are arranged alternately; A plurality of current distributors corresponding to a plurality of electrode groups one by one, in each electrode group, the positive electrode column and the negative electrode column are respectively connected to the positive electrode and the negative electrode of the current distributor; the current distributor is connected to a power supply to adjust the voltage applied to the corresponding electrode group; the current distributor also has a power-on parameter reading back function, a polarity conversion function, a short-circuit function and a disconnection function; The controller is used to control the on / off and voltage regulation of the corresponding current distributor according to the current conditions in each area, and to change the series and parallel connection status between multiple power modules to adjust the output voltage and current of the power supply.

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