JP7474524B2 - Method and device for recovering humic substances - Google Patents

Description

The present invention relates to a method and device for fractionating mixed water obtained from lakes, rivers, etc., and in particular to a method and device for recovering humic substances that fractionate and recover humic substances from lake water, river water, etc.

In some lakes, marshes, rivers, etc., a tendency for chemical oxygen demand (COD), an indicator of organic matter in water, to increase has been observed in recent years, despite measures being taken to improve domestic wastewater, etc. One of the causes of this is said to be water pollution caused by the accumulation of dissolved organic matter in lake water, river water, etc.

Such dissolved organic matter is broadly divided into five categories: humic substances, hydrophobic neutral substances, bases, hydrophilic acids, and hydrophilic neutral substances. Among these, humic substances are further divided into soil-based humin and water-based humin. Of these, water-based humin is made up of hydrophobic organic acids (humic acid and fulvic acid), is difficult to decompose, and is said to account for the majority of dissolved organic matter (approximately 30-80%), making it a cause of environmental pollution.

These humic substances are also known to be precursors of disinfection by-products such as trihalomethanes, as they react with the chlorine added during water purification. For this reason, there is a demand to separate and recover humic substances from lake water, river water, etc. that contain sludge.

For example, Patent Document 1 discloses a method for separating and recovering such humic substances, in which mud obtained from the bottom of a water system is mixed with water glass (sodium silicate), then solidified by baking at a prescribed temperature, and the solidified material is immersed in water to transfer the humic substances into the water and produce a solution of the humic substances. This method is said to be a simple process that makes it possible to effectively utilize the humic substances in the water.

JP 2006-306733 A

The method for separating and recovering humic substances described in Patent Document 1 above allows the humic substances to be selectively separated and recovered from mud by first solidifying the humic substances with water glass and then leaching the humic substances into water. However, it is unclear how much of the humic substances contained in the sample mud has been separated and recovered, making it difficult to quantitatively evaluate the amount when conducting water quality surveys of lakes, rivers, etc. In addition, because a firing process and a soaking process are required to separate and recover humic substances, manual intervention is unavoidable in each process, making it difficult to improve work efficiency.

The object of the present invention is to provide a method and device for recovering humic substances that allows both efficient operation and quantification.

In order to solve the above problems, the method for recovering humic substances according to the present invention uses a column containing resin to fractionate and recover humic substances from mixed water obtained from lakes, rivers, etc., and is characterized by including a first water passing step in which a mixture of the mixed water and an acidic solution is passed from one side of the column to the other side to obtain non-adsorbed substances, and a second water passing step in which, after the first water passing step, an alkaline solution is passed from the other side of the column to the one side to obtain humic substances.

According to this invention, a column containing resin is used, and mixed water is passed from one side of the column to the other to obtain non-adsorbed substances, and then an alkaline aqueous solution is passed from the other side of the column to the first side. By simply switching the flow direction of the feed material flowing through the column, humic substances can be separated and recovered, making it possible to achieve both efficient work and quantification.

In the above-mentioned invention, a washing step may be further included after the second water passing step, in which the resin enclosed in the column is washed with an acidic solution. With this invention, it is possible to repeat the first water passing step and subsequent steps after the washing step, which further improves the efficiency of the work and also makes it possible to support automatic operation.

On the other hand, the humic substance recovery device according to the present invention, which uses a resin-encapsulated column to fractionate and recover humic substances from mixed water obtained from lakes, rivers, etc., is characterized by comprising: a supply unit having a supply tank for each supply substance including the mixed water, the column and a column unit that holds the column, a recovery unit having a recovery tank that recovers substances that have passed through the column, a flow path switching unit that switches the flow direction of the supply substance flowing in the column piping connected to the column unit and is connected to a recovery piping heading toward the recovery unit, a recovery destination selection unit that is provided between the flow path switching unit and the recovery unit and switches the recovery destination of the substance flowing in the recovery piping, and a control unit that controls the operation of all units included in the recovery device.

According to this invention, the flow path switching unit has the function of switching the flow direction of the supply material flowing through the column piping for a column containing resin, so that humic substances can be separated and recovered simply by switching the flow direction of the supply material flowing through the column, making it possible to achieve both efficient work and quantification.

In the above-mentioned invention, a supply source selection unit that selectively switches the supply flow path of the supply material supplied from the supply unit may be provided between the supply unit and the flow path switching unit. According to this invention, it is possible to share (unify) the pump for supplying the supply material to the flow path switching unit, thereby further simplifying the device configuration.

Furthermore, in the above-mentioned invention, the column units connected to the flow path switching unit may be configured to be provided in parallel. According to such an invention, the fractionation capacity of the entire device can be improved, and it is also possible to prepare (set up) one column unit while another column unit is in use, for example.

1 is a schematic diagram showing an outline of a humic substance recovery device according to a representative example of the present invention; FIG. 2 is a side view showing an overview of the supply unit shown in FIG. 1 . 2 is a partial plan view showing an overview of a supply source selection unit shown in FIG. 1; 2 is a partial plan view showing an outline of the flow path switching unit shown in FIG. 1 . 5A and 5B are schematic diagrams of the column unit shown in FIG. 1, in which FIG. 5A is a plan view and FIG. 5B is a right side view. 2 is a partial plan view showing an outline of a collection destination selection unit shown in FIG. 1; FIG. 2 is a schematic diagram showing the operation of a preparation step in a method for recovering humic substances according to a representative example of the present invention. FIG. 2 is a schematic diagram showing the operation of the first water passing step in a method for recovering humic substances according to a representative example of the present invention. FIG. 2 is a schematic diagram showing the operation of the first water passing step in a method for recovering humic substances according to a representative example of the present invention. FIG. 2 is a schematic diagram showing the operation of the acid adjustment step in a method for recovering humic substances according to a representative example of the present invention. A schematic diagram showing the operation of the second water passing step in a humic substance recovery method according to a representative example of the present invention. A schematic diagram showing the operation of the second water passing step in a humic substance recovery method according to a representative example of the present invention. FIG. 11 is a schematic diagram showing the operation of the washing step in a modified embodiment of the method for recovering humic substances according to the present invention. FIG. 11 is a schematic diagram showing the operation of the washing step in a modified embodiment of the method for recovering humic substances according to the present invention.

The specific outline of the method and device for recovering humic substances according to the present invention will be described below with reference to the drawings. In this specification, "mixed water obtained from lakes, rivers, etc." refers not only to lake water or river water, but also to fresh water in general, including water supply and sewage systems.

Figure 1 is a schematic diagram showing an outline of a humic substance recovery device according to a representative example of the present invention. As shown in Figure 1, a humic substance recovery device 100 according to a representative example of the present invention includes a supply unit 110 having a supply tank for each supply material including mixed water obtained from a lake, a river, etc., which is the object to be fractionated, a column unit 150 including a column C containing a resin, a recovery unit 170 having a recovery tank for recovering the material after passing through the column C, a supply source selection unit 120 that selects a flow path for the supply material supplied from the supply unit 110, a liquid delivery pump 130 that sucks the supply material from the supply tank and pushes it out downstream, a flow path switching unit 140 that switches the flow path so that the supply material supplied from the liquid delivery pump 130 is sent to the column unit 150 or the recovery unit 170 described later, a recovery destination selection unit 160 that is arranged between the flow path switching unit 140 and the recovery unit 170 and switches the recovery destination of the material after passing the water, and a control unit 180 that controls the operation of all units included in the recovery device 100.

Figure 2 is a side view showing an overview of the supply unit 110 shown in Figure 1. As shown in Figure 2, the supply unit 110 includes, as an example, a supply base 111, a mixed water tank 112 for storing mixed water SS obtained from a lake, a river, or the like that is the measurement target, a low-concentration acid tank 113 and a high-concentration acid tank 114 for storing aqueous solutions of, for example, hydrochloric acid (HCl) at a predetermined concentration, and an alkali tank 115 for storing aqueous solutions of, for example, sodium hydroxide (NaOH) at a predetermined concentration.

Here, as an example of a supply material, mixed water SS is used, which is obtained from lakes, rivers, etc., and has been filtered to remove large debris and other debris beforehand, and then a specific acid is added to adjust the pH to 2. On the other hand, the HCl aqueous solutions LA and HA stored in the low-concentration acid tank 113 and high-concentration acid tank 114 are adjusted so that the low-concentration acid LA is 0.01 M and the high-concentration acid HA is 0.1 M (note that M = mol/L), respectively, and the alkaline aqueous solution AL stored in the alkaline tank 115 is adjusted to 0.1 M.

The mixed water tank 112, low-concentration acid tank 113, high-concentration acid tank 114, and alkali tank 115 are each fitted with supply pipes 112a, 113a, 114a, and 115a, which are connected to a supply source selection unit 120, which will be described later, and are sucked and supplied by the suction pressure from the liquid supply pump 130. Furthermore, as shown in FIG. 2, it is preferable that the mixed water tank 112 is placed on a weighing device such as a weighing scale 116.

Here, a communication line 181 is connected to the weighing scale 116, which measures the weight of the mixed water tank 112, for example, and transmits an output signal to the control unit 180. This allows the amount of mixed water SS supplied to be adjusted based on the weight (for example, automatic control is possible, such as stopping the supply when the weight has decreased by a predetermined amount since the start of supply).

Figure 3 is a partial plan view showing an overview of the supply source selection unit 120 shown in Figure 1. Note that Figure 3 is a cutaway view in which a part of the housing is cut away so that the inside of the supply source selection unit 120 can be seen. As shown in Figure 3, the supply source selection unit 120, as an example, is equipped with a substantially hollow box-shaped housing 121, a supply pipe switching mechanism 122 provided inside the housing 121, and a supply pipe 123 connected from the supply pipe switching mechanism 122 to a liquid delivery pump 130 described later, and a communication line 182 for exchanging signals with a control unit 180 is connected to the housing 121.

The supply pipe switching mechanism 122 is connected to the above-mentioned supply pipes 112a, 113a, 114a, and 115a, and has the function of selectively switching between these supply pipes 112a to 115a and the downstream supply pipe 123. As a result, the multiple supply tanks 112 to 115 are connected to the liquid delivery pump 130 in a one-to-one correspondence, so the liquid delivery pump 130 is shared (combined into one), which further simplifies the device configuration and prevents the supply materials from being mixed and supplied at the same time.

Here, examples of the liquid delivery pump 130 include a diaphragm pump and a rotary pump, but a peristaltic tube pump is particularly preferred. As shown in FIG. 1, the liquid delivery pump 130 is connected to a communication line 183 that receives signals such as output commands from the control unit 180.

Figure 4 is a partial plan view showing an overview of the flow path switching unit 140 shown in Figure 1. As in the case of Figure 3, Figure 4 also shows the inside of the flow path switching unit 140 as a cutaway view with a part of the housing cut away. As shown in Figure 4, the flow path switching unit 140 is, for example, composed of a substantially hollow box-shaped housing 141, a flow path selection mechanism 142 provided inside the housing 141, a first flow direction switching mechanism 143, and a second flow direction switching mechanism 144, and a communication line 184 is connected to the housing 141 to exchange signals with the control unit 180.

The flow path selection mechanism 142 is connected to the feed pipe 131 from the liquid feed pump 130 on the inlet side, and is connected to the first internal pipe 142a and the second internal pipe 142b on the outlet side. The flow path selection mechanism 142 has the function of switching the flow path so that the supply material sent from the feed pipe 131 is connected to only one of the first internal pipes 142a or 142b.

The first flow switching mechanism 143 is connected to the first internal pipe 142a on the inlet side, and to the first column pipe 143a and the first recovery pipe 143b on the outlet side. The first flow switching mechanism 143 has the function of switching between either of the flow paths, connecting the supply material flowing through the first internal pipe 142a to the first column pipe 143a, or connecting the material flowing from the first column pipe 143a after passing through the column to the first recovery pipe 143b.

Similarly, the second flow switching mechanism 144 is connected to the second internal pipe 142b on the inlet side, and to the second column pipe 144a and the second recovery pipe 144b on the outlet side. The second flow switching mechanism 144 has the function of switching between two flow paths: connecting the supply material flowing through the second internal pipe 142b to the second column pipe 144a, or connecting the material flowing from the second column pipe 144a after passing through the column to the second recovery pipe 144b.

Figure 5 is a schematic diagram of the column unit 150 shown in Figure 1, with Figure 5(a) being a plan view and Figure 5(b) being a right side view. As shown in Figure 5, the column unit 150 includes, as an example, a support member 151 extending in the vertical direction, a pair of gripping members 152 provided on the support member 151, and a column C gripped by the pair of gripping members 152.

The column C applied to the humic substance recovery device 100 according to the present invention is composed of a cylindrical column body C1, a pair of cover members C2 that close both ends of the column body C1 to form an internal space, and a resin RC that is housed in the internal space. Here, the resin RC that is used is a non-ionic XAD-8 (or DAX-8) resin that is a copolymer of acrylic and divinylbenzene and has an MR structure (mega-mesh structure).

One of the pair of cover members C2 is connected to the first column pipe 143a from the flow path switching unit 140 described above, and the other of the cover members C2 is connected to the second column pipe 144a. Therefore, when the mixed water SS described above is flowed from one side of the column C into the resin RC made of XAD-8 (or DAX-8) resin, hydrophobic substances including humic substances are adsorbed to one side of the resin RC.

The pair of gripping members 152 are attached to the support member 151 via hinges 153 and are configured to rotate around the axis 153a. Here, the gripping members 152 are preferably latch-slide type clamps. This makes it possible to accommodate columns C of various sizes (thicknesses).

Referring to both Figures 4 and 5, the flow path selection unit 140, which is one of the major features of the humic substance recovery device according to the present invention, first selects, based on a command from the control unit 180, whether the supply material sent from the feed pipe 131 is to flow in the first internal pipe 142a or the second internal pipe 142b using the flow path selection mechanism 142. Here, when the first internal pipe 142a is selected, the first flow switching mechanism 143 connects the first internal pipe 142a to the first column pipe 143a, and closes the first recovery pipe 143b. As a result, the supply material flowing through the first internal pipe 142a is supplied to column C from the upper side in Figure 5 through the first column pipe 143a.

Then, the supply material sent to column C passes through resin RC and then flows through second column pipe 144a into second flow switching mechanism 144. At this time, second column pipe 144a and second recovery pipe 144b are connected in second flow switching mechanism 144, and second internal pipe 142b is closed. As a result, the material that passed through column C is sent from second recovery pipe 144b to recovery destination selection unit 160.

On the other hand, when the second internal pipe 142b is selected by the flow path selection mechanism 142, the second internal pipe 142b and the second column pipe 144a are connected in the second flow switching mechanism 144, and the second recovery pipe 144b is closed. As a result, the supply material flowing through the second internal pipe 142b is supplied to column C from the lower side in the illustration of FIG. 5 through the second column pipe 144a.

Then, the supply material sent to column C passes through the resin filter RC and then flows through the first column pipe 143a into the first flow switching mechanism 143. At this time, the first column pipe 143a and the first recovery pipe 143b are connected in the first flow switching mechanism 143, and the first internal pipe 142a is closed. As a result, the material that has passed through the column is sent from the first recovery pipe 143b to the recovery destination selection unit 160.

Figure 6 is a partial plan view showing an overview of the destination selection unit 160 shown in Figure 1. As in Figure 3, Figure 6 shows a cutaway view of a part of the housing so that the inside of the destination selection unit 160 can be seen. As shown in Figure 6, the destination selection unit 160 is, for example, composed of a substantially hollow box-shaped housing 161, a merging mechanism 162 and a destination selection mechanism 163 provided inside the housing 161, and a communication line 185 is connected to the housing 161 for exchanging signals with the control unit 180.

The merging mechanism 162 is connected to the first recovery pipe 143b and the second recovery pipe 144b from the flow path selection unit 140 on the inlet side, and to the merging pipe 162a on the outlet side. The merging mechanism 162 has a function of preventing backflow by closing the connection to the other pipe when a supply material or a material that has passed through column C flows from either the first recovery pipe 143b or the second recovery pipe 144b based on a command from the control unit 180.

The recovery destination selection mechanism 163 is connected to the junction pipe 162a on the inlet side, and is connected to the acid recovery pipe 163a, the alkali recovery pipe 163b, the non-adsorbed substance recovery pipe 163c, the humic substance recovery pipe 163d, and the drain pipe 163e on the outlet side. Also, referring to FIG. 1, the acid recovery pipe 163a, the alkali recovery pipe 163b, the non-adsorbed substance recovery pipe 163c, the humic substance recovery pipe 163d, and the drain pipe 163e are connected to the acid recovery tank 171, the alkali recovery tank 172, the non-adsorbed substance recovery tank 173, the humic substance recovery tank 174, and the drain recovery tank 175, respectively.

The recovery destination selection mechanism 163 has the function of switching the pipes connected to the recovery destination tank so that the substances flowing from the junction pipe 162a flow into one of the acid recovery pipe 163a, the alkali recovery pipe 163b, the non-adsorbed substance recovery pipe 163c, the humic substance recovery pipe 163d, and the drain pipe 163e based on commands from the control unit 180.

At least the non-adsorbed material recovery tank 173 and the humic material recovery tank 174 are fitted with lids, and it is preferable that the lids are provided with valves that can be opened and closed. This makes it possible to reduce the so-called dead volume and prevent contamination of the recovered materials from the outside.

Next, the specific operation of a method for recovering humic substances according to a representative example of the present invention will be described with reference to Figures 7 to 12.

Figure 7 is a schematic diagram showing the operation of the preparation step in a humic substance recovery method according to a representative example of the present invention. First, in preparation for carrying out the humic substance recovery method according to the present invention, the control unit 180 drives the liquid delivery pump 130 to supply high-concentration acid HA to the flow path switching unit 140 with the supply source selection unit 120 selecting communication with the high-concentration acid tank 114 (preparation step).

When carrying out this preparation step, the control unit 180 repeatedly switches the flow path in the flow path switching unit 140 to supply the high-concentration acid HA to the first column pipe 143a, the second column pipe 144a, the column unit 150, the first recovery pipe 143b, and the second recovery pipe 144b. At this time, since it is often unclear what substances remained in each flow path before the preparation step, the supplied high-concentration acid HA is led to the drain recovery tank 175 via the drain pipe 163e in the recovery destination selection unit 160. These operations prevent air from remaining in the various pipes when fractionation is carried out.

Figures 8 and 9 are schematic diagrams showing the operation of the first water passing step in a representative example of a method for recovering humic substances according to the present invention. Next, as shown in Figure 8, the control unit 180 drives the liquid delivery pump 130 to supply the mixed water SS to the flow path switching unit 140 with the supply source selection unit 120 selecting communication with the mixed water tank 112.

At this time, the control unit 180 switches the flow path in the flow path switching unit 140 so that the mixed water SS is supplied from the first column piping 143a (see FIG. 4) to column C, and issues a command to the recovery destination selection unit 160 to select the drain recovery tank 175 as the recovery destination. As a result, the mixed water SS supplied from the mixed water tank 112 is passed through one side (the upper side in FIG. 5) of column C via the first column piping 143a, and the high-concentration acid HA that was present in the piping during the preparation process is discharged from the second recovery piping 144b via the recovery destination selection unit 160 to the drain recovery tank 175.

Next, as shown in FIG. 9, the control unit 180 issues a command to the destination selection unit 160 to select the non-adsorbed material recovery tank 173 as the destination, and continues to supply the mixed water SS (first water passing process). At this time, the mixed water SS is supplied at a supply rate of 1 ml/min, for example. As a result, the non-adsorbed materials in the mixed water SS that has passed through column C are collected in the non-adsorbed material recovery tank 173, and the hydrophobic materials in the mixed water SS are adsorbed by the resin RC of column C.

Figure 10 is a schematic diagram showing the operation of the acid adjustment process in a representative example of a method for recovering humic substances according to the present invention. Next, the control unit 180 drives the liquid delivery pump 130 to supply low-concentration acid LA to the flow path switching unit 140 while the supply source selection unit 120 selects communication with the low-concentration acid tank 113.

At this time, the control unit 180 switches the flow path in the flow path switching unit 140 so that the low-concentration acid LA is supplied from the first column pipe 143a (see FIG. 5) to column C, as in the case shown in FIG. 8, and issues a command to the destination selection unit 160 to select the drain recovery tank 175 as the destination. As a result, the low-concentration acid LA supplied from the low-concentration acid tank 113 is passed through one side (the upper side in FIG. 5) of column C via the first column pipe 143a, and the mixed water SS that was present in the pipe during the first water passing process is discharged from the second recovery pipe 144b via the destination selection unit 160 to the drain recovery tank 175 (acid adjustment process).

Figures 11 and 12 are schematic diagrams showing the operation of the second water passing step in a representative example of a method for fractionating humic substances according to the present invention. Next, as shown in Figure 11, the control unit 180 drives the liquid delivery pump 130 to supply the alkaline aqueous solution AL to the flow path switching unit 140 while the supply source selection unit 120 selects communication with the alkaline tank 115.

At this time, the control unit 180 switches the flow path in the flow path switching unit 140 so that the alkaline aqueous solution AL is supplied from the second column piping 144a (see FIG. 4) to column C, and issues a command to the recovery destination selection unit 160 to select the drain recovery tank 175 as the recovery destination. As a result, the alkaline aqueous solution AL supplied from the alkaline tank 115 is passed through the other side (lower side in FIG. 5) of column C via the second column piping 144a, and the low-concentration acid LA that was present in the piping and column C during the acid adjustment process is discharged from the first recovery piping 143b via the recovery destination selection unit 160 to the drain recovery tank 175.

Next, as shown in FIG. 12, the control unit 180 issues a command to the destination selection unit 160 to select the humic substance recovery tank 174 as the recovery destination, and continues to supply the alkaline aqueous solution AL (second water passing process). At this time, the alkaline aqueous solution AL is supplied at a supply rate of, for example, 0.3 ml/min. As a result, the humic substances among the hydrophobic substances adsorbed to the resin RC are eluted together with the alkaline aqueous solution AL flowing in the reverse direction through the column C, and are recovered in the humic substance recovery tank 174.

With this configuration and operation, the humic substance recovery method and recovery device according to the present invention uses a flow path switching unit with a function of switching the flow direction of the supply material flowing through the column piping to pass mixed water from one side of the column to the other side to obtain non-adsorbed substances, and then passes an alkaline aqueous solution from the other side of the column to one side to obtain humic substances. This allows the humic substances to be fractionated and recovered simply by switching the flow direction of the supply material flowing through the column, making it possible to achieve both efficient work and quantification.

Next, the specific operation of the humic substance fractionation method according to a modified example of the present invention will be described with reference to Figures 13 and 14.

Figures 13 and 14 are schematic diagrams showing the operation of the washing step in the humic substance fractionation method according to a modified example of the present invention. In the humic substance fractionation method according to a modified example of the present invention, following the second water passing step shown in Figures 11 and 12 above, a washing step is carried out to remove the supply material remaining in column C of the recovery device and various pipes. That is, as shown in Figure 13, the control unit 180 drives the liquid delivery pump 130 to supply high-concentration acid HA to the flow path switching unit 140 with the supply source selection unit 120 selecting communication with the high-concentration acid tank 114.

At this time, the control unit 180 switches the flow path in the flow path switching unit 140 so that the high-concentration acid HA is supplied from the first column pipe 143a to column C, and then issues a command to the destination selection unit 160 to select the drain recovery tank 175 as the destination from the second recovery pipe 144b. As a result, the high-concentration acid HA supplied from the high-concentration acid tank 114 is passed through one side of column C via the first column pipe 143a, and the supply material (particularly the alkaline aqueous solution AL) present in the first column pipe 143a and the second recovery pipe 144b is discharged to the drain recovery tank 175 via the destination selection unit 160.

Next, as shown in FIG. 14, the control unit 180 issues a command to switch the flow path in the flow path switching unit so that the high-concentration acid HA is supplied from the second column pipe 144a to column C, and then flows from the first recovery pipe 143b to the recovery destination selection unit 160, and to continue the supply of the high-concentration acid HA. As a result, the high-concentration acid HA supplied from the high-concentration acid tank 114 is passed through the other side of column C via the second column pipe 144a, and the supply material present in the second column pipe 144a and the first recovery pipe 143b is discharged to the drain recovery tank 175 via the recovery destination selection unit 160. Then, if the process proceeds directly from this state to the preparation process shown in FIG. 7, it is possible to repeatedly carry out the recovery method according to the present invention.

By performing such an operation, the humic substance recovery method according to the modified example of the present invention makes it possible to repeat the first water passing step and subsequent steps directly after the washing step, thereby further improving the efficiency of the work and enabling the system to be operated automatically.

Although the embodiments of the present invention and variations based thereon have been described above, the present invention is not necessarily limited to these examples. Furthermore, a person skilled in the art will be able to find various alternative embodiments and modifications without departing from the spirit of the present invention or the scope of the appended claims.

For example, in the specific example described above, multiple column units 150 connected to the flow path switching unit 140 may be arranged in parallel. This improves the fractionation capacity of the entire device and also makes it possible to prepare (set up) one column unit while another is in use.

In addition, in the above specific example, after carrying out the preparation process shown in FIG. 7, a "preliminary organic matter measurement process" may be carried out in which high-concentration acid HA is passed through one side of column C (the upper side in FIG. 5) via the first column piping 143a and discharged from the second recovery piping 144b via the recovery destination selection unit 160 to the acid recovery tank 171. At this time, by analyzing the components of the recovered high-concentration acid HA, it is possible to determine the components and amount of organic matter that had previously adhered to the resin RC enclosed in column C.

As with the above-mentioned "pre-organic substance measurement process," after carrying out the second water passing step shown in FIG. 12, a "post-organic substance measurement process" may be carried out in which the alkaline aqueous solution AL is passed through one side of the column C (the upper side in FIG. 5) via the first column piping 143a and discharged from the second recovery piping 144b via the recovery destination selection unit 160 to the alkali recovery tank 172. At this time, by analyzing the components of the recovered alkaline aqueous solution AL, it is also possible to ascertain the components and amount of organic matter attached to the resin RC after carrying out the humic substance recovery method according to the present invention.

100 Recovery device 110 Supply unit 112 Mixed water tank 113 Low concentration acid tank 114 High concentration acid tank 115 Alkaline tank 120 Supply source selection unit 122 Supply pipe switching mechanism 130 Liquid feed pump 140 Flow path switching unit 142 Flow path selection mechanism 143 First flow direction switching mechanism 143a First column pipe 143b First recovery pipe 144 Second flow direction switching mechanism 144a Second column pipe 144b Second recovery pipe 150 Column unit 151 Support member 152 Grip member 160 Recovery destination selection unit 162 Confluence mechanism 163 Recovery destination selection mechanism 170 Recovery unit 171 Acid recovery tank 172 Alkaline recovery tank 173 Non-adsorbed substance recovery tank 174 Humic substance recovery tank 175 Drain recovery tank 180 Control unit

Claims (8)

A method for recovering humic substances, comprising the steps of: supplying a mixed water to be measured to a column containing a nonionic acrylic resin that adsorbs hydrophobic substances including humic substances; and fractionating and recovering the humic substances,
a first flow path through which the liquid flows from one side of the column to the other side thereof and into a destination selection unit connected to the first recovery pipe;
a second flow path through which the liquid flows from the other side of the column toward the one side thereof and through a second recovery pipe to the destination selection unit;
a liquid delivery pump that selects one of the feed materials, the mixed water, the low-concentration acid, the high-concentration acid, and the alkaline aqueous solution, by a feed source selection unit, sucks the selected feed material from a feed tank, and pushes the selected feed material out to a downstream side;
a flow path switching unit that switches a connection destination of a feed pipe from the liquid feed pump to the first flow path or the second flow path;
a control unit for controlling operations of the supply source selection unit, the liquid delivery pump, and the flow path switching unit,
a first water passing step of passing the mixed water through the column via the first flow path while measuring a supply amount by switching the flow path switching unit to cause the hydrophobic substance to be adsorbed onto the resin, and sending a non-adsorbed substance to a non-adsorbed substance recovery tank via the recovery destination selection unit;
an acid adjustment step of switching the flow path switching unit to pass the low-concentration acid through the column via the first flow path and sending the mixed water to a drain recovery tank via the recovery destination selection unit;
a second water passing step in which the flow path switching unit is switched to pass the alkaline aqueous solution through the column via the second flow path, thereby sending the low-concentration acid to a drain recovery tank via the destination selection unit, and then sending the humic substances among the hydrophobic substances adsorbed on the resin to a humic substance recovery tank via the destination selection unit;
are given in order,
A method for recovering humic substances, comprising: a preparatory step, prior to the first water passing step, of switching the flow path switching unit to supply high concentration acid so that it permeates each of the flow path switching unit, the column, the first recovery pipe, and the second recovery pipe; and preventing air from remaining in the flow path switching unit, the column, the first recovery pipe, and the second recovery pipe when the humic substances are fractionated into the humic substance recovery tank in the first water passing step, the acid adjustment step, and the second water passing step. The method for recovering humic substances as described in claim 1, characterized in that the first water passing process comprises discharging the high concentration acid in the piping via the destination selection unit to a drain recovery tank, and then sending non-adsorbed substances to a non-adsorbed substance recovery tank via the destination selection unit. 3. The method for recovering humic substances according to claim 1 or 2 , wherein the supply amount in the first water passing step is measured from the weight of a mixed water tank that stores the mixed water. A method for recovering humic substances described in any one of claims 1 to 3, characterized in that the non-adsorbent substance recovery tank and the humic substance recovery tank are connected to the recovery destination selection unit by a non-adsorbent substance recovery pipe and a humic substance recovery pipe, respectively, and are provided with a lid and a valve to prevent external contamination of the recovered substances. A humic substance recovery device for supplying a mixed water to be measured to a column containing a nonionic acrylic resin that adsorbs hydrophobic substances including humic substances, and fractionating and recovering the humic substances, comprising:
a first flow path through which the liquid flows from one side of the column to the other side thereof and into a destination selection unit connected to the first recovery pipe;
a second flow path through which the liquid flows from the other side of the column toward the one side thereof and through a second recovery pipe to the destination selection unit;
a liquid delivery pump that selects one of the feed materials, the mixed water, the low-concentration acid, the high-concentration acid, and the alkaline aqueous solution, by a feed source selection unit, sucks the selected feed material from a feed tank, and pushes the selected feed material out to a downstream side;
a flow path switching unit that switches a connection destination of a feed pipe from the liquid feed pump to the first flow path or the second flow path;
a control unit for controlling operations of the supply source selection unit, the liquid delivery pump, and the flow path switching unit;
The control unit
a first water passing step of passing the mixed water through the column via the first flow path while measuring a supply amount by switching the flow path switching unit to cause the hydrophobic substance to be adsorbed onto the resin, and sending a non-adsorbed substance to a non-adsorbed substance recovery tank via the recovery destination selection unit;
an acid adjustment step of switching the flow path switching unit to pass the low-concentration acid through the column via the first flow path and sending the mixed water to a drain recovery tank via the recovery destination selection unit;
a second water passing step in which the flow path switching unit is switched to pass the alkaline aqueous solution through the column via the second flow path, thereby sending the low-concentration acid to a drain recovery tank via the destination selection unit, and then sending the humic substances, which are among the hydrophobic substances adsorbed onto the resin, to a humic substance recovery tank via the destination selection unit;
A humic substance recovery device characterized in that, prior to the first water passing step, a preparation step is performed in which the flow path switching unit is switched to supply high concentration acid so that it spreads throughout the flow path switching unit, the column, the first recovery pipe, and the second recovery pipe, and when the humic substances are fractionated into the humic substance recovery tank in the first water passing step, the acid adjustment step, and the second water passing step, the fractionation is performed so as not to leave air in the flow path switching unit, the column, the first recovery pipe, or the second recovery pipe. The humic substance recovery device as described in claim 5, characterized in that the first water passing process discharges the high concentration acid in the piping via the recovery destination selection unit to a drain recovery tank, and then sends non-adsorbed substances to a non-adsorbed substance recovery tank via the recovery destination selection unit. 7. The apparatus for recovering humic substances according to claim 5 or 6, further comprising a weighing scale for measuring the weight of a mixed water tank that stores the mixed water, and for measuring the supply amount in the first water passing step. A humic substance recovery device described in any one of claims 5 to 7, characterized in that the non-adsorbent substance recovery tank and the humic substance recovery tank are connected to the recovery destination selection unit by a non-adsorbent substance recovery pipe and a humic substance recovery pipe , respectively , and are provided with a lid and a valve to prevent external contamination of the recovered substances.

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