KR102294957B1 - Backwashing system for activated carbon layer - Google Patents

Abstract

The present invention provides a system and method for washing an activated carbon layer in an adsorbent that can suppress the loss of the activated carbon layer. The system includes: adsorption paper for accommodating therein an activated carbon layer for filtering water; a sampler for collecting a portion of the water located above the activated carbon layer in the adsorbent; a particle shape analyzer for measuring the size of activated carbon particles contained in the water collected by the sampler; and a control unit for calculating an expansion rate of the activated carbon layer based on the measured size of the activated carbon grains, and adjusting the strength for washing the activated carbon layer based on the calculated expansion rate. When it is assumed in the water filtration process that the height from the lower end of the activated carbon layer accommodated in the adsorption paper to the upper end of the activated carbon layer is called the activated carbon first layer height, and it is assumed in the backwashing process that the height from the lower end of the activated carbon layer to the upper end of the activated carbon layer is called the activated carbon second layer height, the expansion rate of the activated carbon layer is calculated as the expansion rate (%) of the activated carbon layer = (height of expansion/height of the first activated carbon layer) x 100.

Description

BACKWASHING SYSTEM FOR ACTIVATED CARBON LAYER

The present invention relates to a washing system for an activated carbon layer provided in an adsorbent in a water purification plant for supplying tap water.

Water purification plants for supplying tap water include a water intake plant for raw water intake, a mixed paper for mixing water and water purification chemicals, a settling tank for removing foreign substances by precipitating them through agglomeration process, and a sedimentation tank to remove impurities while passing the sedimented water through the sand filtration membrane. It may consist of a filter paper (adsorption paper) to remove and a purified paper for storing purified water from which impurities have been removed.

The filter paper can remove impurities using activated carbon or an activated carbon layer. If the activated carbon layer is used for a certain period of time, foreign substances or suspended substances may accumulate in the activated carbon layer of the filter paper, thereby reducing the water passage and adsorption capacity of the activated carbon layer. . Periodic backwashing of the activated carbon layer is required in order to recover the water passage and adsorption capacity of the activated carbon layer.

Backwashing stops filtration and forcibly injects water into the activated carbon bed in the opposite direction to the water flow in the filtration process when the turbidity is trapped in the activated carbon bed in the activated carbon adsorbent and reaches the allowable maximum loss head or when the water quality reaches the allowable value. The activated carbon is expanded and suspended to wash the filter layer blocked by the water flow.

The activated carbon layer is expanded by backwashing. Since the expansion of the activated carbon layer corresponds to an important management factor related to the removal of foreign substances and the loss of the activated carbon layer, it is important to control and manage it.

However, in the prior art, in order to measure the expansion rate of the activated carbon layer, the ozone process is stopped in the water treatment facility, and the investigator directly collects samples at various depths using the sampling equipment at the site using the expansion rate measuring device, and then uses the same. Therefore, the extent of expansion of the activated carbon layer is measured manually. Therefore, in order to satisfy the target expansion rate, field personnel are frequently input and manual work is required, so accurate measurement is difficult and very cumbersome.

1. Unexamined Patent Publication No. 10-2018-0009916

The present invention relates to a system and a washing method for washing an activated carbon layer in an adsorbent which can accurately measure the expansion rate of the activated carbon layer and suppress the loss or loss of the activated carbon layer when washing the activated carbon layer in the adsorbent.

The present invention, an adsorption paper for accommodating therein an activated carbon layer for filtering water; a sampler for collecting a portion of the water located above the activated carbon layer in the adsorbent; a particle shape analyzer for measuring the size of activated carbon particles contained in the water collected by the sampler; and a control unit that calculates the expansion rate of the activated carbon layer based on the measured size of the activated carbon grains, and adjusts the strength for washing the activated carbon layer based on the calculated expansion rate; to provide.

In the water filtration process, the height from the lower end of the activated carbon layer accommodated in the adsorption paper to the upper end of the activated carbon layer is called the activated carbon first bed height, and in the backwashing process, from the lower end of the activated carbon layer to the upper end of the activated carbon layer Assuming that the height is the height of the second layer of activated carbon, the expansion rate of the activated carbon layer is calculated by the following <Equation 1>.

<Equation 1>

Expansion rate (%) of the activated carbon layer = (height of expansion/height of the first floor of activated carbon) × 100

Expansion height = the height of the second floor of activated carbon - the height of the first floor of activated carbon

Here, the second layer height of the activated carbon is the height of the water from which the activated carbon particles are collected when the size of the activated carbon particles contained in the water collected by the sampler during the backwashing process falls within a preset reference value range, and the sample The collector can collect water inside the adsorbent by varying the height, and the reference value of the activated carbon grains is preferably 0.1 mm to 1.5 mm.

The size of the activated carbon grains is the average particle size of a plurality of activated carbon grains present in the water collected by the sampler, or the size of the activated carbon grains is the plurality of activated carbon grains present in the water collected by the sampler. The effective diameter may be the effective diameter of the activated carbon particles, and the effective diameter may be the particle diameter of the activated carbon particles passing a predetermined numerical range in the particle size and dropping curve.

Further comprising a pump for injecting a washing solution into the activated carbon layer in a direction opposite to the flow direction of water passing through the activated carbon layer in the water filtration process, wherein the control unit outputs the pump when the calculated expansion rate does not reach the target expansion rate increases, and when the calculated expansion rate exceeds the target expansion rate, the output of the pump is decreased.

The present invention identifies the granular activated carbon contained in the collected filtered water through a particle shape analyzer when washing the activated carbon layer in the adsorbent paper, and calculates the expansion height of the activated carbon layer based on the result of measuring the size of the identified granular activated carbon particles, , it is possible to accurately measure the expansion rate of the activated carbon layer based on the calculated expansion height, and by controlling the accurately measured expansion rate, it is possible to accurately and smoothly perform washing of the activated carbon layer, and to suppress the loss or loss of the activated carbon layer. can

1 shows an embodiment of an activated carbon layer washing system in a filter paper according to the present invention.
2 is a flowchart of a method for washing an activated carbon layer in an adsorbent paper;
3 shows the measurement of the bed height of the activated carbon layer in the filtration process before washing the activated carbon layer.

The objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments taken in conjunction with the accompanying drawings. In addition, the terms used are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of the user operator. Therefore, definitions of these terms should be made based on the content throughout this specification.

1 shows an embodiment of the activated carbon bed washing system in the adsorbent of the present invention, FIG. 2 is a flowchart related to the method for washing the activated carbon bed in the adsorbent, and FIG. 3 is the activated carbon in the filtration process prior to washing the activated carbon layer. Measures the floor height of the floor.

1 to 3, the activated carbon bed washing system in the sorbent paper is a filter paper 15, an activated carbon layer 18 or activated carbon in the sorbent 15, a sampler (or a sample collection and height measurement device, 12) , a particle shape analyzer 13 , and a control unit 14 . The adsorption paper 15 refers to a place or accommodation space where backwashing is performed for filtration or removal of foreign substances, and since the adsorption paper 15 is a place for filtering water, it may be expressed as a filter paper.

The activated carbon layer 18 may be disposed in the adsorption paper 15 , and may remove impurities contained in water flowing into the adsorption paper 15 . The activated carbon layer 18 may have a structure in which granular or particulate activated carbon is stacked in a layer form, and the water flowing into the adsorption paper 15 passes through the activated carbon layer 18 so that impurities contained in water can be removed. .

The activated carbon layer 18 in the adsorption paper 15 may be located at the lower part of the adsorption paper 15 , and water for filtration is introduced into the activated carbon layer 18 and temporarily stored on the activated carbon layer 18 . can be For example, referring to FIG. 3 , for water filtration, the flow meter 11 can control the amount of water flowing into the adsorption paper 15, and is higher than the trough 19 located on the activated carbon layer 18. 15) The height of the stored water can be adjusted. The height of the water can be adjusted to be higher than the trough for filtration. In this case, the trough 19 may be a passage for draining a washing liquid (washing water) for washing the activated carbon layer.

On the other hand, as shown in FIG. 1 , the water level in the suction paper 15 can be adjusted so that the water level in the suction paper 15 is lower than the trough 19 before backwashing is started by the flow meter 11 . have. The sampling and height measuring device 12 collects a portion of the water stored in the absorbent paper 15 (hereinafter referred to as “sample”) when the activated carbon layer 18 is washed.

For example, the sampling and height measuring device 12 collects a portion of water located at various heights while moving up and down while varying the height in the adsorption paper 15 when the activated carbon layer 18 is washed.

2 and 3, the layer height (a) of the activated carbon layer 18 in the filtration process is obtained (S105).

The sampling and height measuring device 12 may measure the floor height (a) of the activated carbon layer 18 in the filtration process. That is, in the water filtration process, the sampling and height measuring device 12 may be moved to the top (or top surface) of the activated carbon layer 18 . In addition, the height from the lowermost (or lowermost surface) of the activated carbon layer 18 to the uppermost (or uppermost surface) of the activated carbon layer 18 may also be measured, which is referred to as 'activated carbon first floor height'. In other words, the activated carbon first layer height means the height from the lower end of the activated carbon layer accommodated in the adsorbent paper to the upper end of the activated carbon layer in the filtration process of filtering water.

And, in the activated carbon layer backwashing process, which will be described later, the activated carbon layer expands upward as the flow rate for washing counterflow flows in the reverse direction (described below). In this backwashing process, the height from the lower end of the activated carbon layer to the upper end of the activated carbon layer is referred to as 'activated carbon second layer height'.

The sample collection and height measuring device 12 may include a function of measuring the height of the point at which the sample is collected, so that the expanded position of the activated carbon layer can be detected. The sampling and height measuring device 12 may be moved in the vertical direction in the sorbent 15 . That is, the sample collection and height measuring device 12 of the present invention can measure the position (height) of the sample to be collected while measuring the sample inside the suction paper 15 by being located inside the suction paper 15 . A method of measuring the height of the point at which the sample is taken may be performed by various means. For this purpose, as an example, various means such as a wire capable of measuring the distance at which the sampling means provided at the end of the sample collector enters into the water inside the filter paper will be possible. This is to measure the distance of the collection means entering the inside of the filter paper, and various other methods are also applicable.

The sampling and height measuring device 12 is represented as one configuration for measuring the sample and the height, but is not limited thereto. In another embodiment, the sample collector and the height measuring device may be provided as separate components. In addition, the sample collection and height measuring device 12 may be expressed by being replaced with a “sample collector”, and the sample collector may be capable of both sampling and measuring the height.

Referring to FIG. 1 , the floor height a of the activated carbon layer 18 may be changed due to abrasion, loss or generation of powdered coal during washing of the activated carbon layer 18 as the operating period increases. Actual measurement is essential to accurately calculate the expansion rate. The floor height (a) (or height) of the activated carbon layer 18 measured in the filtration process is referred to as “the first floor height of the activated carbon” for convenience.

Next, the filtration process is stopped and a washing process (also referred to as a “backwashing process”) on the activated carbon layer is performed (S110). First, the filtration process for the activated carbon layer 18 is stopped, and the height of the water in the sorbent 15 may be adjusted so that the level of water in the sorbent 15 is lower than that of the trough 19 . In addition, a washing solution (eg, water) is forcibly injected into the activated carbon layer 18 in a direction opposite to the flow direction of water passing through the activated carbon layer 18 in the filtration process by using the pump 16 or input to the activated carbon layer. (18) can be washed.

The washing liquid (eg, water) may be injected or injected into the activated carbon layer 18 through or through the lower water collecting device 17 . By the backwashing process, the activated carbon layer 18 is expanded in an upward direction. The density of the activated carbon layer 18 per unit volume (eg, m 3 ) may be reduced.

Next, during the backwashing process, a portion (sample) of water in the absorbent paper 15 positioned at a height of the activated carbon first layer or higher is collected using the sampling and height measuring device 12 (S120). Next, the size (eg, particle diameter or diameter) of the activated carbon particles included in the sample collected by using the particle shape analyzer 13 is measured ( S130 ).

Next, the size of the activated carbon grains measured by the control unit 14 and a reference value are compared, and the expansion height of the activated carbon layer 18 is calculated based on the comparison result (S140 to S150). That is, information on the measured size of the activated carbon grains may be transmitted to the control unit 14, and the control unit 14 may compare the measured size of the activated carbon grains with a preset reference value (S140).

If the size of the measured activated carbon grains is larger than the reference value, the control unit 14 moves the sample collection and height measuring device 12 to a higher position (S145). And the moved sample collection and height measuring instrument 12 may collect a portion of the water (sample) in the adsorbent 15 at a higher position (S120).

Next, using the particle shape analyzer 13, the size (eg, particle diameter, or diameter) of the activated carbon particles included in the sample can be measured ( S130 ), and the control unit 14 controls the control unit 14 to measure The size of the activated carbon grains and a reference value are compared (S140).

Steps S120 to S145 may be repeatedly performed until the condition of step S140 is satisfied. For example, the sample collection and height measuring device 12 may take samples at various points while moving up and down, and may also measure the height of each point.

The preset reference value of the activated carbon grains may be set in consideration of the expansion rate of the activated carbon expanded by the flow rate of the pump 160 . For example, the size of the activated carbon grains may be the average particle size (or diameter) of the grains measured by the particle shape analyzer 13 , and the reference value may be 0.1 mm to 1.5 mm.

In another embodiment, the size of the activated carbon grains may be the largest particle size among the particle sizes of the measured or detected grains. In another embodiment, the size of the activated carbon grains may be the smallest among the particle sizes of the measured or detected grains.

In another embodiment, the size of the activated carbon grains may be the effective diameter of the activated carbon grains, and in this case, the effective diameter may be 10% of the particle size passing through the particle size and dropping curve of the activated carbon.

Next, when the size of the activated carbon grains falls within the reference value range, the height (position) at which the sample is collected is called the "activated carbon second floor height", and through this, the controller 14 controls the expansion height (h) of the activated carbon layer 18. ) can be calculated, that is, the height of the second layer of activated carbon is the height of the sampling point by the sampling and height measuring device 12 when the size of the activated carbon grains is within the reference value range.

The control unit 14 may calculate the result of subtracting the activated carbon first floor height from the activated carbon second floor height as the expansion height (h) of the activated carbon layer. The controller 14 may calculate the expansion rate of the activated carbon layer 18 using the expansion height h and the numerical value of the activated carbon first floor height.

[Expansion rate of the activated carbon layer (%)] = Expansion height (h) / Activated carbon first floor height (a) × 100

Next, the control unit 14 may adjust the washing intensity for washing the activated carbon layer 18 based on the calculated expansion rate of the activated carbon layer 18 . The control unit 14 may adjust at least one of a flow rate of a washing solution (or washing water) for washing the activated carbon layer 18, a flow rate of the washing solution, or a hydraulic pressure of the washing solution based on the calculated expansion rate of the activated carbon layer 18 .

The control unit 14 may increase the washing flow rate of the activated carbon layer 18 by increasing the output of the inverter pump 16 capable of controlling the flow rate when the calculated expansion rate does not reach the target expansion rate. On the other hand, when the calculated expansion rate exceeds the target expansion rate, the output of the pump 16 may be reduced to reduce the washing flow rate of the activated carbon layer 18 . The flow rate for the backwashing process may be feedback-controlled so that the expansion rate calculated through this process reaches the target expansion rate.

The present invention can accurately measure the expansion height and expansion rate of the activated carbon layer based on the result of measuring the size of the granular activated carbon grains of the washing water collected through the incident shape analyzer 13 during the backwashing process, and Based on the feedback control of the flow rate of backwashing, backwashing can be smoothly performed within a management range, and loss or loss of the activated carbon layer 18 can be suppressed.

Although the preferred embodiment of the present invention has been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims are also provided. is within the scope of the

[Explanation of numbers on drawings]

12: sampler (or sampler and height meter)

13: Particle Shape Analyzer

14: control unit

15: activated carbon absorbent paper

16: pump

17: lower water catchment device

18: activated carbon or activated carbon layer

19: trough

Claims (10)

Adsorption paper for accommodating therein an activated carbon layer for filtering water; a sampler for collecting a portion of the water located above the activated carbon layer in the adsorbent; a particle shape analyzer for measuring the size of activated carbon particles contained in the water collected by the sampler; and a control unit that calculates the expansion rate of the activated carbon layer based on the measured size of the activated carbon grains, and adjusts the strength for washing the activated carbon layer based on the calculated expansion rate. The water inside the adsorbent is collected by varying the height in the
In the water filtration process, the height from the lower end of the activated carbon layer accommodated in the adsorption paper to the upper end of the activated carbon layer is called the activated carbon first bed height, and the height from the lower end of the activated carbon layer to the upper end of the activated carbon layer in the backwashing process is When the activated carbon second floor height is called, and the expansion height is the difference between the activated carbon second floor height and the activated carbon first floor height, the expansion rate of the activated carbon layer is calculated by the following <Equation 1>,
<Equation 1>
Expansion rate (%) of the activated carbon layer = (height of expansion/height of the first floor of activated carbon) × 100
The second layer height of the activated carbon is the height of the water from which the activated carbon particles are collected when the size of the activated carbon particles contained in the water collected by the sampler during the backwashing process falls within a preset reference value range,
The activated carbon grain reference value is 0.1mm ~ 1.5mm,
The activated carbon particle size is an activated carbon layer backwashing system, characterized in that the average particle size of a plurality of activated carbon particles present in the water collected by the sampler. delete delete delete delete delete According to claim 1,
The size of the activated carbon particles may be an effective diameter of a plurality of activated carbon particles present in the water collected by the sampler, and the effective diameter is the particle diameter of the activated carbon particles passing a predetermined numerical range in the particle size and dropping curve. Activated carbon bed backwashing system characterized. 8. The method of claim 7,
Activated carbon bed backwashing system, characterized in that it further comprises a pump for injecting the washing solution into the activated carbon layer in the opposite direction to the flow direction of the water passing through the activated carbon layer in the water filtration process. delete delete

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