JP7366444B2 - Well cleaning method - Google Patents

Description

The present invention relates to a well cleaning method.

Conventionally, a well cleaning device (hereinafter referred to as "conventional example") disclosed in Japanese Patent Application Laid-Open No. 2005-307575 has been proposed as a device for cleaning a well constructed by disposing a casing body in a borehole. .

In this conventional example, a brush is installed on the outer circumferential surface of a pumping pipe that can be inserted into a well to scrape off dirt adhering to the inner circumferential surface of the well.By moving this brush up and down, the inside of the well is It is used for cleaning.

Japanese Patent Application Publication No. 2005-307575

By the way, as mentioned above, when cleaning a well using the conventional method, it is necessary to remove the existing water pump, pumping pipe, and other pumping equipment from the well, and then install the pumping equipment again after cleaning, which is a cumbersome process. be.

The present invention has been made in view of the above-mentioned problems, and provides an innovative well cleaning method that has never existed before.

The gist of the present invention will be explained with reference to the accompanying drawings.

A method for cleaning a well 1 comprising a casing body 2 provided in an excavated hole 50 in the ground and having a strainer portion 2a, and a pump 3 provided in the casing body 2, the method comprising controlling the amount of water pumped by the pump 3. This method relates to a well cleaning method characterized in that unnecessary matter D attached to the strainer portion 2a is removed by raising the strainer portion 2a in stages.

In the well cleaning method according to claim 1, the water pump 3 is a motor pump, and has an inverter 5 that varies the frequency of the power supply supplied to the water pump 3. The present invention relates to a well cleaning method characterized in that the amount of water pumped by the water pump 3 is increased in stages.

Further, in the well cleaning method according to claim 2, the frequency of the power supply supplied to the water pump 3 is increased and varied by the inverter 5 in units of 5 Hz, so that the amount of water pumped by the water pump 3 is increased in stages. The present invention relates to a well cleaning method characterized by the following.

The well cleaning method according to any one of claims 2 and 3 is characterized in that the frequency range is from 30 Hz to 50 Hz.

Further, in the well cleaning method according to any one of claims 1 to 4, a first step of performing pumping treatment at a pumping amount of 30 to 35 L/min in the pump 3 for a predetermined time; A second step in which the water pump 3 pumps water at a pumping amount of 53 to 58 L/min for a predetermined period of time, and following this second step, the water pump 3 pumps water at a pumping amount of 70 to 75 L/min for a predetermined period of time. a third step, a fourth step in which the water pump 3 pumps water at a pumping rate of 85 to 90 L/min for a predetermined period of time; The present invention relates to a well cleaning method characterized by comprising a fifth step of pumping water at a rate of 103 to 108 L/min for a predetermined period of time.

Further, in the well cleaning method according to any one of claims 1 to 5, the well 1 is a hot spring well.

Since the present invention is configured as described above, the well can be cleaned easily and effectively, resulting in an innovative well cleaning method that has not been seen before.

FIG. 2 is an explanatory diagram of a well 1 according to the present embodiment. FIG. 2 is an enlarged explanatory view of a state in which unnecessary matter D has adhered to a water passage hole 2a' of a strainer portion 2a according to the present embodiment. FIG. 2 is an explanatory diagram of a well cleaning method according to the present embodiment. FIG. 2 is an explanatory diagram of test results for confirming the effectiveness of this example.

Embodiments of the present invention that are considered suitable will be briefly described by showing the effects of the present invention based on the drawings.

Regarding the cleaning of the well 1, the present inventors thought that it would be possible to clean the well 1 without removing the pumping equipment such as the pump 3 and the pumping pipe 6 from the well 1 as in the conventional example described above. Focusing on the fact that the unnecessary matter D adhering to the strainer part 2a can be sufficiently removed by increasing the amount of water pumped in , and as a result of various tests, an unprecedented method for cleaning the well 1 was developed.

Specifically, in the well 1, over time, unnecessary matter D (dirt) adheres to the inner edge of the opening of the water passage hole 2a' of the strainer portion 2a, and this unnecessary matter D tends to block the water passage hole 2a'. As the water grows (the degree of opening of the water hole 2a' becomes smaller), the amount of pumped water gradually decreases, so it is necessary to remove the unnecessary matter D attached to the water hole 2a' (see Figure 2). ).

Therefore, the inventors of the present invention confirmed that by increasing the output of the water pump 3 to increase the amount of pumped water (flow velocity) compared to the normal operation of the water pump 3, it was possible to remove the unnecessary matter D attached to the water passage hole 2a'.

However, if the water pumping amount is increased too much at once in an attempt to sufficiently remove the waste matter D attached to the water passage hole 2a', the degree of opening of the water passage hole 2a' is reduced by the waste matter D, and the vicinity The flow velocity increases rapidly, and fine earth and sand from the ground located around the outside of the casing body 2 (strainer part 2a) is sucked into the casing body 2, resulting in clogging of the water passage hole 2a' and clogging of the water pump 3. It was confirmed that problems such as causing damage occurred.

Therefore, when the amount of water pumped by the water pump 3 was increased in stages, it was possible to remove the dirt adhering to the water passage hole 2a' without sucking in fine earth and sand from the ground.

Specifically, as the amount of water pumped by the pump 3 is increased step by step, the pumped water gradually becomes turbid (not brown turbidity made of fine earth and sand on the ground, but from waste D adhering to the water passage hole 2a'). (black turbidity) becomes noticeable, and at a certain stage the turbidity peaks and disappears, resulting in what is called water conditioning. The fact that the waste material D attached to the water passage hole 2a' has been removed can be confirmed not only by the degree of turbidity of the pumped water but also by the relationship between the output of the pump 3 and the amount of pumped water.

In other words, by increasing the amount of water pumped by the pump 3 in stages, the waste material D adhering to the water passage hole 2a is gradually removed, and the degree of opening of the water passage hole 2a' increases in stages. It is thought that the unnecessary material D could be removed while suppressing the extreme increase in the flow velocity near the water hole 2a', and the well 1 from which the unnecessary material D was removed has a pumping amount that matches the output of the water pump 3. will be obtained.

As described above, the present invention can remove the unnecessary matter D adhering to the casing body 2 by increasing the amount of water pumped in the pump 3 in stages, and it is possible to remove the unnecessary matter D attached to the casing body 2 by increasing the amount of water pumped in the pump 3 in stages. The well 1 can be cleaned without removing pumping equipment such as 6.

Specific embodiments of the present invention will be described based on the drawings.

The present embodiment is a method for cleaning a well 1 (well device) comprising a casing body 2 provided in an excavated hole 50 in the ground and having a strainer portion 2a, and a pump 3 provided within the casing body 2.

In this example, the well 1 to be cleaned is a hot spring well ^, as shown in FIG. A plurality of slit-shaped water passage holes having a length in the longitudinal direction of the casing body 2 are provided in an intermediate part of the casing body 2 (a part that becomes a water source). Strainer section 2a (approximately 400 m in total in the range of 800 m to 1500 m underground in the casing body 2) in which pipe members 2' (approximately 6 to 12 mm in width, approximately 10 to 30 cm in length) are arranged in parallel in the circumferential direction. A long strainer portion 2a) is provided, and a water pump 3 (pump equipped with a water level gauge) is further disposed within the casing body 2, with a water pump 6 provided at its lower end.

Further, the specifications of the water pump 3 used in this embodiment are as follows.
5.5kw x 50Hz x 3φ x 200V (27.5A)
Maximum pumping amount (105L/min) x maximum pumping head (139mH)

Further, this embodiment has a control section 4 that controls the operation of the water pump 3, and this control section 4 is provided with an inverter 5 (inverter circuit).

This inverter 5 converts the power (DC voltage) supplied to the water pump 3 into an alternating current voltage of a predetermined frequency and outputs it as driving power for the water pump 3.

Therefore, by providing the inverter 5, the frequency (rotation speed) of the water pump 3 can be set to an arbitrary value according to the required amount of pumped water, reducing electricity consumption to the necessary minimum and reducing costs. In addition, the life of the water pump 3 can be extended.

In this embodiment, the frequency during normal operation is set to 25 Hz (the motor rotation speed of the water pump 3 is 1500 rpm), and the frequency during cleaning is set in the frequency range of 30 Hz to 50 Hz, as will be described later. Of course, the frequencies during normal operation and during cleaning are not limited to the above.

A method of cleaning the well 1 having the above configuration will be explained.

By increasing the amount of water pumped in the pump 3 in stages, unnecessary substances D (clogging substances such as scale and iron bacteria) attached to the casing body 2 are removed.

Specifically, there is a first step in which the water pump 3 pumps water at a pumping rate of 30 to 35 L/min for a predetermined period of time, and following this first step, the water pump 3 pumps water at a pumping amount of 53 to 58 L/min. a second step that is carried out for a predetermined period of time; a third step that is followed by a pumping process of 70 to 75 L/min in the pump 3 for a predetermined period; A fourth step is performed in which water is pumped at a rate of 85 to 90 L/min for a predetermined period of time, and following this fourth step, a fifth step is performed in which water is pumped at a rate of 103 to 108 L/min in the pump 3 for a predetermined period of time.

More specifically, in the first step, as shown in FIG. Water is pumped at a rate of 32L/min (0.000533m ³ /sec) for 1 to 2 hours. Note that the flow velocity (LV) is 0.0109 m/sec, and this pumped water amount of about 32 L/min is a load factor of 13.6% during the excavation pumping test (235 L/min). The present inventors believe that the maximum stable water pumping amount during excavation pumping test (235 L/min) is about 141 L/min (load factor 60%).

During this first process, the pumped water contains a small amount of unnecessary material D, and the dynamic water level at the start of the process (the water level inside the casing body 2 when the pump 3 is operating) is about 80 m, and about The dynamic water level after 30 minutes was about 90 m, the dynamic water level after about 60 minutes was about 90 m, and the dynamic water level was stable after about 30 minutes. As a result of repeated tests, it was found that in the first step, it is desirable to pump water at a pumping rate of 30 to 35 L/min using the pump 3.

In the second step, as shown in (b) in FIG. 2, the frequency of the driving power supplied to the water pump 3 is set to 35 Hz (the motor rotation speed of the water pump 3 is 2100 rpm), and the water pumping amount is approximately 55 L/min (0 .0009167m ³ /sec) is pumped for 1 to 2 hours. Note that the flow velocity (LV) is 0.0187 m/sec, and this pumped water amount of about 55 L/min is a load factor of 23.4% during the excavation pumping test (235 L/min).

During this second process, the pumped water contains a small amount of unnecessary material D, and the dynamic water level at the start of the process is approximately 91 m, the dynamic water level after approximately 30 minutes is approximately 97 m, and the hydraulic water level after approximately 60 minutes is approximately 97 m. The dynamic water level was approximately 98 m and stabilized after approximately 60 minutes. As a result of repeated tests, it was found that in the second step, it is desirable for the pump 3 to pump water at a pumping rate of 53 to 58 L/min.

In the third step, as shown in (c) in FIG. 2, the frequency of the driving power supplied to the water pump 3 is set to 40 Hz (the motor rotation speed of the water pump 3 is 2400 rpm), and the pumped water amount is approximately 73 L/min (0 .0012166m ³ /sec) is pumped for 1 to 2 hours. Note that the flow velocity (LV) is 0.0187 m/sec, and this pumped water amount of approximately 73 L/min is a load factor of 31.1% during the excavation pumping test (235 L/min).

During this third process, the pumped water is in a black and turbid state containing a large amount of waste D, and the dynamic water level at the start of the process is approximately 100 m, and after approximately 30 minutes, the dynamic water level is approximately 105 m, and approximately 60 m After about 60 minutes, the dynamic water level was approximately 106 m, and after about 60 minutes, the dynamic water level became stable. As a result of repeated tests, it was found that in the third step, it is desirable to pump water at a pumping rate of 70 to 75 L/min using the pump 3.

In the fourth step, as shown in (d) in FIG. 2, the frequency of the driving power supplied to the water pump 3 is set to 45 Hz (the motor rotation speed of the water pump 3 is 2700 rpm), and the pumped water amount is approximately 88 L/min (0 .0014667 m ³ /sec) is pumped for 1 to 2 hours. Note that the flow velocity (LV) is 0.02989 m/sec, and this pumped water amount of about 88 L/min is a load factor of 37.4% during the excavation pumping test (235 L/min).

During this fourth step, the pumped water was in a black and turbid state containing a large amount of waste D, and the dynamic water level at the start of the process was about 106 m, and after about 30 minutes, the dynamic water level was about 111 m, and about 60 m After about 60 minutes, the dynamic water level was approximately 112 m, and after about 60 minutes, the dynamic water level became stable. As a result of repeated tests, it was found that in the third step, it is desirable to pump water at a pumping rate of 85 to 90 L/min using the pump 3.

In the fifth step, as shown in (e) in FIG. 2, the frequency of the driving power supplied to the water pump 3 is set to 50 Hz (the motor rotation speed of the water pump 3 is 3000 rpm), and the pumped water amount is approximately 105 L/min (0 .00175m ³ /sec) is pumped for 1 to 2 hours. Note that the flow velocity (LV) is 0.03567 m/sec, and this pumped water amount of about 105 L/min is a load factor of 44.68% during the excavation pumping test (235 L/min).

During this fifth step, the pumped water contains a very small amount of unnecessary material D, and the dynamic water level at the start of the process is about 112 m, the dynamic water level after about 30 minutes is about 117 m, and after about 60 minutes The dynamic water level was approximately 118 m, and the dynamic water level stabilized after approximately 60 minutes. As a result of repeated tests, it was found that in the third step, it is desirable to pump water at a pumping rate of 103 to 108 L/min using the pump 3.

From the above results, in this embodiment, when cleaning the well 1, the frequency of the power supply supplied to the water pump 3 is increased in the frequency range of 30 Hz to 50 Hz in 5 Hz increments using the inverter 5. The amount of pumped water can be increased in stages, and the unnecessary matter D attached to the strainer portion 2a can be effectively removed.

Incidentally, in this specification, "stepwise" means that when moving from the current process to the next process, the water pumping amount (rotation speed) in the water pump 3 is increased to the next level at once without stopping the water pump 3. means to raise. That is, each process is carried out by keeping a constant pumping amount (rotational speed) for a certain period of time, and when the current process is completed, the operation is continuously shifted to the next process in a stepwise manner without interruption.

FIG. 4 is a graph showing the test results of the change over time in the amount of spring water in the well 1. The amount of spring water increases each time the cleaning process of this example is performed, and its effectiveness can be confirmed. Note that each cleaning process is performed at a predetermined interval.

Since the present embodiment is configured as described above, by increasing the amount of water pumped in the water pump 3 in stages, it is possible to remove the unnecessary matter D attached to the casing body 2 (water passage hole 2a'), which is similar to the conventional method. The well 1 can be cleaned without removing pumping equipment such as the pump 3 and the pumping pipe 6 from the well 1 as in the example.

Furthermore, in this embodiment, the water pump 3 is a motor pump, and has an inverter 5 that varies the frequency of the power supply supplied to the water pump 3. Since the amount is increased stepwise, the above-mentioned effects can be reliably achieved.

Further, in this embodiment, the amount of water pumped by the water pump 3 is increased in stages by increasing the frequency of the power supply supplied to the water pump 3 in a frequency range of 30 Hz to 50 Hz in 5 Hz increments using the inverter 5. , the above-mentioned effects can be reliably achieved.

In addition, this embodiment includes a first step in which the water pump 3 pumps water at a pumping rate of 30 to 35 L/min for a predetermined period of time, and subsequent to this first step, a pumping process in which the water pump 3 pumps water at a pumping rate of 53 to 58 L/min. a second step in which the treatment is carried out for a predetermined period of time, a third step in which the water pump 3 pumps water at a pumping rate of 70 to 75 L/min for a predetermined period following the second step; A fourth step in which pumping water is pumped at a pumping rate of 85 to 90 L/min for a predetermined period of time, and a fifth step is subsequent to this fourth step in which pumping processing is carried out at a pumping pump 3 at a pumping amount of 103 to 108 L/min for a predetermined period of time. By performing the steps based on the test results, the above-mentioned effects can be reliably achieved.

In this embodiment, since the well 1 is a hot spring well, the advantage of this embodiment (the advantage of being able to clean water well in the shortest possible time without removing pumping equipment such as the pump 3 and the pumping pipe 6 from the well 1) is fully exhibited. can do.

Note that the present invention is not limited to the embodiments, and the specific configuration of each component can be designed as appropriate.

D Unnecessary items 1 Well 2 Casing body 2a Strainer part 3 Water pump 5 Inverter
50 drill holes

Claims (6)

A method for cleaning a well comprising a casing body provided in an excavated hole in the ground and having a strainer part, and a pump provided in the casing body, the method comprising: increasing the amount of water pumped in the pump in stages; A well cleaning method characterized by removing unnecessary substances attached to a strainer part. 2. The well cleaning method according to claim 1, wherein the water pump is a motor pump, and has an inverter that varies the frequency of the power supply supplied to the water pump, and the frequency is varied by the inverter to increase the water pumping in the water pump. A well cleaning method characterized by increasing the amount in stages. 3. The well cleaning method according to claim 2, wherein the frequency of the power supply supplied to the water pump is increased in 5 Hz increments by the inverter, thereby increasing the amount of water pumped by the water pump in stages. Well cleaning method. 4. The well cleaning method according to claim 2, wherein the frequency range is 30 Hz to 50 Hz. The well cleaning method according to any one of claims 1 to 4, including a first step in which the pump pumps water at a pumping rate of 30 to 35 L/min for a predetermined period of time, and following this first step, the pump pump a second step in which a pumping process is carried out at a pumping rate of 53 to 58 L/min for a predetermined period of time, and a third step, following this second step, in which a pumping process is carried out at a pumping rate of 70 to 75 L/min in the pumping pump for a predetermined period; This third step is followed by a fourth step of pumping water at a pumping rate of 85 to 90 L/min using the water pump for a predetermined period of time; and following this fourth step, pumping water at a pumping rate of 103 to 108 L/min using the water pump. A well cleaning method characterized by comprising a fifth step of carrying out the treatment for a predetermined period of time. 6. The well cleaning method according to claim 1, wherein the well is a hot spring well.

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