JPS6048211B2 - Electromagnetic filter cleaning method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an electromagnetic filter for the purpose of removing crud in high-temperature, high-pressure water systems in thermal power plants, nuclear power plants, etc.
This invention relates to a cleaning process for a so-called high-gradient electromagnetic filter that generates a high-gradient magnetic field.

Generally, an electromagnetic filter is equipped with a matrix and an electromagnetic coil that magnetizes the matrix, and performs a filtration process in which suspended particles (cladding) of ferromagnetic and weakly magnetic substances in a fluid are captured by the matrix using magnetic force and separated and removed. However, if crud accumulates in the matrix and the differential pressure increases due to continued filtration, or if the quality of the filtrate deteriorates due to a decline in filtration function, filtration must be interrupted and the matrix must be cleaned. Must be.

For this cleaning, there is usually a cleaning method in which when high-temperature, high-pressure water is filtered, brushing is performed in the opposite direction using the body's own energy without using an external cleaning source. That is, on the filtrate outflow side of the matrix of the electromagnetic filter, there is provided a space at least equal to or larger than the matrix volume, preferably 2 to 3 times the volume, and on the other hand, a quick-opening valve is provided in the flush drainage channel on the inflow side of the matrix gate. It has been proposed that high-temperature, high-pressure filtered water is sealed in a space and the quick-opening valve is opened to cause the water to flow back into the matrix for cleaning. However, since this cleaning method does not use an external cleaning source, there is a limit to the cleaning efficiency, and a very high cleaning effect cannot be expected, and there are also problems in the treatment of cleaning waste water.

In order to accurately solve these problems, the present invention controls the cleaning process to maximize the cleaning effect in flash cleaning, and at the same time condenses and temporarily stores cleaning waste water for subsequent treatment. The object of the present invention is to provide a method and a device for making it easier to use.

Another object of the present invention is to provide an effective method and apparatus for simplifying the operation and maintenance of a high-gradient electromagnetic filter, making it possible to perform safe and extremely economical cleaning operations.

One of the features of this invention is that it filters high-temperature, high-pressure water. A method for cleaning a high-gradient electromagnetic filter in which flush wastewater is mixed into cold water in a flash tank and treated while controlling the matrix differential pressure to be kept constant, for example, in the range of 1 to 10k9fIc1t during cleaning of the high-gradient electromagnetic filter. There are two reasons why. Another important feature of the present invention is that a suitable device for carrying out the cleaning method is a high-gradient three-way filter, which is equipped with a matrix in a filtration tank and equipped with an electromagnetic coil for magnetizing the matrix. A pressure regulating valve is provided in the flush drainage passage in the electromagnetic filter, and in order to control the pressure regulating valve, a differential pressure detection end of the matrix during cleaning, which is connected to the pressure regulating valve, is disposed within the electromagnetic filter body, and the To provide a cleaning device for a high gradient electromagnetic filter, in which a flash drainage channel is connected to a flash tank having a mechanism for storing cold water and mixing flush drainage into the cold water.

In this case, the amount of cold water stored in the flash tank is below 100'C after receiving and mixing the entire amount of flash wastewater, and the total capacity of the flash tank is sufficient to receive the cold water and the entire amount of flash wastewater, and It is effective to use a flash tank equipped with a mechanism for mixing flush wastewater into cold water.

To explain an embodiment of the present invention with reference to the drawings, a matrix 2 is held in an electromagnetic filter body 1 by a water flow partition plate 3, and a space 4 and a space 5 are defined on the inflow side and the outflow side, respectively. The space 4 has a volume that is at least more than the volume of the matrix 2, preferably 2 to 3 times the volume.

The water flow partition plate 3 is made of a perforated plate or the like, and serves to hold the matrix 2 such as steel wool and at the same time distribute water flow uniformly. Further, an electromagnetic coil 6 is arranged surrounding the outside of the matrix 2, and when a direct current flows through the electromagnetic coil 6, the matrix 2 is magnetized, and furthermore, the magnetic force is converged on the sharp part of the steel wool. The structure is such that a high gradient is generated.In addition, an inflow valve 8 is provided in an inflow passage 7 communicating with a space 5 on the matrix inflow side.
The cladding in the high-temperature, high-pressure water that flows into the electromagnetic filter body 1 through the inflow valve 8 is usually a ferromagnetic or weakly magnetic material, so it is captured and held by the steel wool by magnetic force while passing through the matrix 2. It is becoming more and more common. The filtered water from which these cruds have been removed passes through the space 4 on the outflow side and returns to the system from the top through an outflow path 10 located in the outflow valve 9. Note that the bypass flow path 11 directly connects the inflow path 7 and the outflow path 10, and a bypass valve 12 is provided in this flow path. A flash drainage channel 13 branched from the inflow channel 7 is connected directly to the flash tank 15 via a quick-open valve 14 and a pressure control valve 14', or to a distributing channel constructed by a perforated pipe or the like provided in the flash tank 15. It is connected and coupled to the user 16.

In this case, instead of the distributor 16, a structure may be adopted in which the flash drainage channel 13 is introduced in the tangential direction along the side plate of the flash tank 15, in short, the cold water previously stored in the flash tank and the electromagnetic filter It is only necessary to provide a mechanism for quickly and uniformly mixing the cleaning wastewater discharged from the main body 1. Said flash tan;. An exhaust pipe 19' having an exhaust valve 19 is provided at the top of the tank.

Furthermore, on the inflow and outflow sides of the matrix 2,
A pressure detection end 20 is provided, and the pressure before and after the matrix 2 during cleaning is detected and transmitted to a differential pressure indicating controller 21 .

In response to this, the differential pressure indicating controller 21 detects the differential pressure in the matrix 2, sends a signal to the pressure regulating valve 14', and controls the pressure regulating valve 14' to maintain the set differential pressure. . In this case, the quick-opening valve 14 may be operated in conjunction with each other or may be operated separately, and furthermore, after the quick-opening valve 14 is operated, the pressure regulating valve 14' may be operated in conjunction with the quick-opening valve 14. During filtration with the electromagnetic filter, the inflow valve 8 and outflow valve 9 open, and the quick-open valve 14 and bypass valve 12 open.
is closed and operated, and the electromagnetic coil 6 is energized.

That is, the high-temperature, high-pressure water to be treated enters the space 5 of the electromagnetic filter body 1 through the inlet valve 8, and then the crud is removed while passing through the matrix 2, and the overflow water flows from the space 4 through the outflow valve 9 into the system. Return to As this filtration continues, crud accumulates in the matrix 2 and the differential pressure increases, or the water quality deteriorates due to a decline in the filtration function.If this is detected, the filtration is interrupted and the cleaning process is started. Move. When entering this cleaning process, first open the bypass valve 12, close the outflow valve 9, then close the inflow valve 8, and close the electromagnetic coil 6.
energization is stopped.

As a result, the high-temperature, high-pressure water is bypassed from the bypass channel 11, and the high-temperature, high-pressure water is retained inside the electromagnetic filter body 1 as it is. On the other hand, into the flash tank 15, with the exhaust valve 19 open and the drain valve 18 closed, the cold water inflow valve 17 is opened to introduce cold water until the distributor 16 is submerged, and the cold water inflow valve 17 is closed. The amount of cold water introduced into the flash tank is such that the water temperature in the flash tank 15 does not exceed 100°C after receiving cleaning waste water from the electromagnetic filter, and the total capacity of the flash tank 15σ is calculated from the amount of cold water introduced and the flash tank. The amount must be sufficient to accept the entire amount of cleaning wastewater.
In such a state, the quick-open valve 1 in the flush drainage flow path 13
4, the high temperature and high pressure water in the electromagnetic filter main body 1 undergoes a rapid depressurization, causing a portion of it to evaporate and expand its volume, causing the water in the space 4 to rapidly flow down inside the matrix 2, causing its The shearing force causes the crud attached to the steel wool to be peeled off and removed.

This cleaning flow rate generates a pressure difference across the matrix 2, which is detected by the pressure detection end 20 and transmitted to the differential pressure indicating controller 21. According to experiments, a sufficient cleaning flow rate was obtained in the matrix 2 using high-temperature, high-pressure water at 160° C. and 6k9flc or more, and a considerable cleaning effect was obtained even at 130° C. and 3k9fld. At that time, the differential pressure before and after the matrix 2 was in the range of 1 to 10k9fIc, and the most effective range was 2 to 5k9f1d. Therefore, if the differential pressure is set in advance within this range using the differential pressure indicating controller 21, the pressure regulating valve 14' will be automatically controlled by the differential pressure indicating controller 21 to maintain the optimal cleaning flow rate. The maximum cleaning effect can be achieved by The flash waste water is dispersed from the distributor 16 into the cold water stored in the flash tank 15 and mixed with it, and the steam mixed in the flash waste water is also condensed by the cold water, and the entire amount is received in the flash tank 15. The temperature of the mixed water is ultimately kept below 100°C.
The material is left to cool as it is, and then the drain valve 18 is opened from the flash tank 15 to take it out to the outside and treated or disposed of depending on the purpose. o The present method and apparatus can also be applied when cleaning is performed using external high-temperature, high-pressure water, without relying on the self-energy of the high-temperature, high-pressure water.

Further, the switching operation of each of the valves may be performed 35 times in succession based on the differential pressure instruction from the differential pressure detection terminal of the matrix 2, or may be controlled by another separate system.

According to the present invention, the cleaning effect of the matrix of the electromagnetic filter can be maximized through simple control in the treatment of high-temperature, high-pressure water, and the entire amount of cleaning waste water is collected in liquid form using a 4θ mechanism using a simple mechanism. It is useful and convenient for operation management, requires only a small capacity flush tank, and the amount of squeeze for brushing is small, allowing for efficient cleaning work, and the ability to self-generate high-temperature, high-pressure water. This enables economical and highly safe cleaning operations that effectively utilize energy.

[Brief explanation of the drawing]

The drawing is a system explanatory diagram of an embodiment of the present invention. 1... Electromagnetic filter body, 2...
Matrix, 3... Water flow partition, 4, 5...
... Space, 6 ... Electromagnetic coil, 7 ...
...Inflow path, 8 ...Inflow valve, 9 ...
...Outflow valve, 10...Outflow path, 11...
・Bypass flow path, 12... Bypass valve, 13.
...Flash drainage channel, 14...Quick opening valve, 14'...Pressure control valve, 15...
Flash tank, 16...Distributor, 17...Cold water inflow valve, 17'...
Cold water inflow path, 18... Drain valve, 18'...
...Drainage channel, 19...Exhaust valve, 19'...
...Exhaust pipe, 20...Pressure detection end, 21...
...Differential pressure indicating controller.

Claims (1)

[Claims] 1. A method for cleaning a high-gradient electromagnetic filter equipped with an electromagnetic coil and a matrix for filtering high-temperature, high-pressure water, the method comprising controlling the differential pressure between the inflow side and the outflow side of the matrix to be kept constant. A method for cleaning an electromagnetic filter, which is characterized in that cleaning wastewater is dispersed and mixed into cold water. 2 The differential pressure between the inflow side and the outflow side of the matrix is 1
The cleaning method according to claim 1, wherein the cleaning method is controlled to a range of 10 kgf/cm^2. 3. The cold water into which the cleaning waste water was diffused and mixed has a temperature of 100%.
3. The cleaning method according to claim 1 or 2, wherein the cleaning method is adjusted so that the temperature is below .degree. 4. Claims 1, 2, or 3, wherein the cleaning waste water is dispersed and mixed into the cold water by opening a quick-open valve that can be opened and closed provided on the inflow side of the matrix. cleaning method. 5. A high gradient electromagnetic filter cleaning device for filtering high-temperature, high-pressure water, which is equipped with an electromagnetic coil and a matrix, is provided with a differential pressure detection section that detects a differential pressure between the inflow side and the outflow side of the matrix, and this differential pressure detection section is provided. A flush drain channel is equipped with a pressure regulating valve and a quick-opening valve that are opened and closed by the operator, and the flush drain channel is equipped with a mechanism for storing cold water and dispersing and mixing cleaning waste water into the cold water. An electromagnetic filter cleaning device connected to a flush tank. 6. The electromagnetic filter cleaning device according to claim 5, wherein the flush tank is sized to receive the entire amount of cleaning waste water and a stored amount of cold water that makes the cleaning waste water less than 100°C. 7. The electromagnetic filter according to claim 5 or 6, wherein the pressure regulating valve is provided on the downstream side of a quick-opening valve located in a flush drainage channel provided on the inflow side of the matrix. cleaning equipment. 8. The electromagnetic filter cleaning device according to claim 5, 6, or 7, wherein the flash drainage channel is connected to the flash tank via a distributor.