JPS58189004A - Moving bed type adsorbing apparatus for upwardly flowing liquid phase - Google Patents

Abstract

PURPOSE:To contrive to enhance adsorbing efficiency, by a method wherein an adsorbent is continuously supplied from above while the waste adsorbent is intermittently or continuously withdrawn from a bottom to hold the level of the packed adsorbent above the outlet of a treating liquid. CONSTITUTION:A liquid to be treated introduced into an adsorbing tower 1 from a supply port 2 is passed through an adsorbing layer 8 in an upwardly directed stream and filtered and separated from an adsorbent by a treated liquid collector 7 to be flowed out of the adsorbing tower 1 from a treated liquid outlet 3 as a treated liquid. On the other hand, a new or a regenerated adsorbent is continuously supplied to the adsorbing tower 1 in a slurry form from the adsorbent supply port 4 provided to the top part of the adsorbing tower. In addition, the level E of the packed adsorbent supplied from the top part of the adsorbing tower 1 is detected by a set of level meters 10, 11 provided above the treated water collector 7 so as to leave a definite distance C while a waste adsorbent withdrawing valve 12 cooperates with the level meters 10, 11 to hold the level E of the packed adsorbent to an almost constant level. As the result, adsorption can be carried out in good efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an adsorption device, and more particularly to a moving bed adsorption device for an upflow liquid phase using a granular adsorbent such as activated carbon.

Adsorption using granular adsorbents and ion exchange resins such as activated carbon, silica gel, activated clay, activated alumina, synthetic zeolite, and synthetic resin, and liquid processing such as ion exchange are used in a wide range of fields such as the food industry, chemical industry, and petroleum industry. It has been used for the purification and decolorization of liquids, and the separation and recovery of specific @retrieved components since ancient times.In recent years, it has also been used in the fields of tertiary treatment of frozen fields, urban sewage, dyeing wastewater, etc., and the field of atomic car V industry. Although adsorption treatment has become an effective and economical treatment method, the adsorption treatment equipment still has many drawbacks.

Adsorption treatment methods using granular adsorbents include fluidized bed adsorption,
Adsorption is roughly divided into moving bed adsorption and fixed bed adsorption, and the moving bed and fixed bed adsorption systems include upward flow method and downward flow method regarding the liquid phase.

In the fluidized bed adsorption treatment method, in order to keep the adsorbent in a fluidized state, the amount of introduced liquid to be treated is kept constant.1.
Since the introduction speed of the liquid to be treated must be maintained above a certain limit, the contact time between the adsorbent and the liquid to be treated may be shortened, resulting in insufficient adsorption treatment, or due to changes in the properties of the liquid to be treated. In addition to the inconvenience of not being able to appropriately select the contact time with the adsorbent, there is also the disadvantage that only highly hard adsorbents can be used because the adsorbent is abraded due to flow.

In fixed bed adsorption treatment, when the adsorption capacity of the adsorbent decreases and the desired treatment result cannot be achieved, the treatment operation is temporarily interrupted and the entire amount of waste adsorbent is replaced or the inside of the equipment is replaced. Because the process regenerates and contributes its activity while still being filled, it is not efficient, and the adsorbent on the outlet side of the treated liquid must be sent to the regeneration process without using its adsorption capacity to its full potential. , it was uneconomical. Furthermore, if the liquid to be treated contains suspended solids (hereinafter referred to as SS), the SS will accumulate in the adsorbent layer and cause clogging, increasing pressure loss. A cleaning operation such as temporarily stopping the adsorption treatment operation, expanding the adsorbent layer by 20 to 50% by passing fresh water, etc. in an upward flow, and removing the SS accumulated in the adsorbent layer by flotation separation is performed. This has the disadvantage that a large amount of fresh water is required for this cleaning, and that the device becomes large because a margin for this expansion is required.

Compared to the fluidized bed type and fixed bed type mentioned above, the moving bed type does not have the above-mentioned drawbacks, but in reality it is not as widely used as the fixed bed type.

The reason for this is that the conventional moving bed system uses a so-called pulse feeding system, which intermittently extracts waste adsorbent whose adsorption capacity has decreased after being used for a certain period of time, and supplies replenishing adsorbent. Therefore, in order to replenish and extract the adsorbent, the processing operation has to be stopped at a certain time, and it is also necessary to measure the amount of adsorbent supplied and withdrawn, re-supply the liquid to be treated, etc. 1. Requires complicated time and effort. However, in order to reduce the number of adsorbent refills and withdrawals, it is necessary to increase the amount of adsorbent replenishment and withdrawal in pulses, but in this case, the amount of adsorption formed in the adsorbent layer There was a drawback that the band caused disturbance during movement of the adsorption layer, causing inconvenience in the subsequent adsorption treatment. In particular, in conventional moving bed adsorption treatment, in the case of upward flow, the upward introduction rate is limited in a low flow rate range.
Slight changes in flow rate 1 caused the adsorbent layer to expand and fluidize, which caused channeling (uneven flow phenomenon) and classification of adsorbent particles, and in many cases the adsorption treatment effect could not be achieved sufficiently. . Furthermore, with the pulse head method, it has not been possible to quickly and effectively deal with variations in the properties of the liquid to be treated or the amount of the liquid.

This invention was made in order to solve the above-mentioned various problems related to conventional liquid adsorbent treatment, and it is possible to continuously supply the adsorbent without temporarily stopping the adsorption treatment. It is an object of the present invention to provide a new and highly efficient adsorption method and apparatus for bringing the liquid to be treated into contact with an adsorbent in an upward flow while continuously moving the layer.

This invention provides an adsorbent supply port at the top of the adsorption tower that continuously supplies an adsorbent made of fresh activated carbon in the form of a slurry.
A processing liquid outlet is provided below the supply port, a powder surface needle is provided between the adsorbent supply port and the processing liquid outlet to detect the adsorbent filling surface, and a processing liquid supply port is provided at the bottom of the adsorption tower. , a waste adsorbent extraction valve is provided to extract waste adsorbent from the lower part of the device in conjunction with the powder surface needle, and the height from the treated liquid outlet F to the adsorbent filling surface is from the treated liquid supply port. The present invention is characterized in that the waste adsorbent extraction valve is controlled so that the height up to the processing liquid outlet is maintained at 4% to 10%.

Embodiments of the present invention will be described below based on the drawings.

Figure 1 shows an example of this simple upward flow liquid phase moving bed type adsorption device using a cylindrical tank. Adsorption tower l from mouth Z
guided within. At this time, a distributor 6 is connected to the liquid to be treated inlet 2 in order to evenly distribute the liquid to be treated over the entire cross-sectional area of the adsorption tower. An embodiment of the distributor 6 is shown in FIGS. 3 and 4. The liquid to be treated passes through the adsorbent layer 8 in an upward flow,
The treated liquid is filtered and separated from the adsorbent by the treated liquid collector 7 and flows out of the adsorption tower 1 from the treated liquid outlet 3. The treated liquid water collectors 7 are, for example, cylindrical wire meshes as shown in FIGS.
Aiming for uniform outflow of the treated liquid from the adsorption tower 1.

The fresh or regenerated adsorbent is continuously fed in the form of a slurry from the adsorbent supply port 4 at the top of the adsorption tower by an appropriate means such as a pump, water ejector 1 pressure tank (not shown), and preferably in a stationary manner. is supplied to the adsorption tower 1. In this case, the adsorbent can also be slurried with the treatment liquid. The adsorbent slurry is uniformly distributed over the entire cross-sectional area of the adsorption tower by the distribution plate 9, and when it enters the adsorption zone D below the water collector 7, it is evenly distributed over the entire cross-sectional area of the adsorption tower by a complete piston flow. be done.

The filling surface E of the adsorbent supplied from the top of the adsorption tower 1 is detected by a set of powder level meters 10.11 installed at a fixed interval C above the treated liquid water collector, and the waste adsorbent is removed. Announcement 1
2 operates in conjunction with the powder level meter 10.11, and the adsorbent filling surface E is maintained at a substantially constant level. That is, the adsorbent filling surface E
When the powder level meter 10 detects that the amount of water has reached the predetermined upper limit B, the waste adsorbent removal valve 12 is activated and the waste adsorbent is removed from the waste adsorption installed at the bottom of the adsorption tower, preferably at the bottom end of the adsorption tower. When the powder level meter 11 detects that the adsorbent is extracted in slurry form from the agent extraction port 5 and the adsorbent filling surface E has reached the lower limit A, the extraction valve 1 is
2, and therefore the withdrawal of waste adsorbent is stopped, and the height of the adsorbent filling surface E is maintained within a certain range C after all.

The lower limit A of the adsorbent filling surface is determined by the weight of the adsorbent in the liquid between the lower limit and the treated liquid water collector 7 and the amount of M in the adsorbent in the adsorption zone D. It is necessary to set it so that no expansion or fluidization occurs.

Now, as shown in Figure @8, as an adsorbent, for example, the average particle size is 1.4 mm, and the wet ratio in water! l 32-1 Takeda X
- In a tube with an inner diameter of 10.2 cm filled with 7000J activated carbon (sold by Takeda Pharmaceutical Co., Ltd.), the height of the adsorption zone was determined by The height of the adsorbent filling surface from the liquid outlet is h', and various superficial linear velocities LV (m
/h), filling rate (h/H) xi 00 (%) and expansion rate ((h'
-h) / (H+h) ) XI 00 (%) is measured and the results are shown in FIG. Here, the negative filling factor is h<
When Q, it means that the activated carbon filling surface is below the processing liquid outlet. As is clear from FIG. 9, if the filling rate is at most 4% or more over the LV range of 15-40 m/h, the packed bed will not expand.

The next question is what is the state of the adsorbent in the adsorption zone, and for that purpose the activated carbon can be used to determine the flow of the activated carbon bed at various superficial linear velocities and packing factors. I checked the condition. The results are shown in FIG. Area (a) indicates an area where activated carbon forms a completely fixed bed, and area (b) indicates an area where activated carbon locally causes a flow such as a minute eddy current. ,
Since almost no disturbance occurs in the activated carbon layer, the desired adsorption effect can be sufficiently achieved. On the other hand, in region (c), the activated carbon is irregularly and relatively large in flow, and in region (d), the activated carbon is completely distributed in the front upper fixed bed part and the front upper fluidized bed part. Separation occurs, resulting in significant disturbance of the activated carbon layer, making it impossible to obtain a satisfactory adsorption effect.

However, the superficial linear velocity that is usually adopted for adsorption treatment using activated carbon is! According to the present invention, if the lower limit of the activated carbon filling surface is maintained in the -F direction from the processing liquid outlet so that the activated carbon filling rate is 4% or more, the conventional upward flow movement can be achieved. It is possible to completely prevent the expansion and fluidization of the adsorbent, which was a drawback of layered adsorption treatment, and therefore, the processing liquid can be introduced at an efficient flow rate without causing channeling or classification of the adsorbent. I can do it.

The minimum filling rate at which expansion and fluidization of the adsorbent will not occur will of course vary depending on the linear velocity of the liquid to be treated, the particle size, specific gravity, porosity, etc. of the adsorbent; Similar experiments have shown that when the minimum filling rate is set to about 10%, the adsorbent does not expand or fluidize in most cases. Clogging up to the top of the adsorption tower is undesirable because it impedes smooth supply of the processing agent.

Therefore, in this invention, the lower limit of the adsorbent filling surface is
It is sufficient if the setting is made to satisfy at least the minimum filling rate. Note that it is clear that the filling rate can be set to exceed the minimum filling rate. In other words, one of the features of this invention is that the lower limit A of the adsorbent filling surface is set so that A/D is equal to or higher than the minimum filling rate.

In addition, powder needle 10. By appropriately selecting the detection interval C of LL, the amount of waste adsorbent extracted can be changed arbitrarily. When the column diameter of the main body 1 is large, it is desirable to provide a baffle plate 13 to assist the movement of the adsorbent by the piston flow, as shown in one embodiment in FIG. 7, for example.

The lower part of the adsorption tower 1 has a conical shape below the liquid to be treated supply port 2, and the lower end is configured as a waste adsorbent outlet 5, above the waste adsorbent outlet 5 and below the liquid to be treated supply port 2. It is desirable to install an inverted cone-shaped baffle plate 14 concentric with the adsorption tower to uniformly extract waste adsorbent over the entire cross-sectional area of the adsorption tower.

When a large amount of liquid is to be processed or when it is necessary to particularly reduce the amount of waste adsorbent extracted at one time, it is preferable to reduce the diameter of the upper part of the adsorption tower, as shown in FIG.

Hereinafter, the case where the waste adsorbent is extracted intermittently has been mainly described, but it is of course also possible to perform both the supply of the adsorbent and the extraction of the waste adsorbent continuously. When the waste adsorbent is extracted intermittently, there is an advantage that the SS accumulated in the adsorbent layer on the side of the liquid to be treated is loosened by the force of the intermittent extraction and is easily discharged.

The mobile upward flow liquid phase adsorption device of the present invention continuously supplies adsorbent from above and extracts waste adsorbent from below intermittently or continuously, so that the adsorbent-filled surface is used as the processing liquid outlet. Unlike conventional moving bed type adsorption treatment, the adsorption treatment is performed completely continuously without stopping the treatment operation even when forming a moving layer of adsorbent. There is no need to measure the amount of waste adsorbent extracted, and the weight of the adsorbent in the liquid above the treated liquid outlet prevents the adsorbent from expanding or fluidizing due to the upward flow of liquid. Since this does not occur, stable processing operations can be continued even when the flow rate of the liquid to be processed changes. Moreover, since the adsorbent is continuously and preferably quantitatively supplied to the adsorption tower l in the form of a slurry, unlike conventional methods, it is easy to connect the waste adsorbent to the regeneration system, and the adsorption system and regeneration system can be easily connected. There is no need to provide a large number of relay tanks between the two.

Furthermore, the adsorption amount of the adsorbent can be easily maintained constant using a water ejector, a pump, etc., and can be easily and quickly changed in response to fluctuations in the quality and flow of the liquid to be treated.

Further, according to the present invention, the filling rate of the adsorbent is 4% or more.
Since it is limited to a range of 0% or less, the superficial linear velocity LV
If it is within a normal range, the adsorbent layer will be maintained in a good state with almost no disturbance, and the adsorbent surface will not dry and form bridges.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, in which FIG. 1 is a schematic front sectional view of the device, FIG. 2 is a schematic front sectional view of another embodiment of the upper part of the device, and FIG. 3 is a schematic front sectional view of the upper part of the device. A plan view, FIG. 4 is a front view, FIG. 5 is a perspective view of the liquid collector, FIG. 6 is a plan view showing an example arranged in an adsorption tower, and FIG. 7 is a rectifier plate. Equipment part! 4, FIG. 8 is a schematic diagram for explaining the filling rate and expansion rate of the adsorbent, FIG. 9 is a diagram showing the relationship between the filling rate and expansion rate at various superficial linear velocities, and Figure 10 is a diagram showing the relationship between the filling rate and expansion rate at various superficial linear velocities.
The figure is a diagram illustrating the state of the adsorbent layer at various superficial linear velocities and filling rates. 1 Adsorption tower, 2 Processed liquid supply port 3 Processed liquid outlet, 4 Adsorbent supply port 5 Distributed adsorbent extraction port,
8 Adsorbent 10.11 Powder needle, 12 Waste adsorbent extraction valve A
Lower limit of the adsorbent filling surface from the processing liquid outlet, B Upper limit of the adsorbent filling surface from the processing liquid outlet. Patent applicant: Takeda Pharmaceutical Co., Ltd. Agent: LH Shin

Claims (1)

[Claims] An adsorbent supply port is provided at the top of the adsorption tower to continuously supply an adsorbent made of fresh activated carbon in the form of a slurry, and a processing liquid outlet is provided below the supply port, and between the adsorbent supply port and the processing liquid outlet. A powder level meter is installed to detect the adsorbent filling surface, and a liquid supply port to be treated is installed at the bottom of the adsorption tower, and a waste adsorbent extractor is installed to extract waste adsorbent from the bottom of the device in conjunction with the powder level meter. A valve is provided so that the height from the treated liquid outlet to the adsorbent filling surface is maintained at 4% or more and 10% or less of the height from the treated liquid supply port to the treated liquid outlet. An upflow liquid phase moving bed adsorption device configured to control a reagent withdrawal valve.