KR810001909B1 - Apparatus for continuous ion exchange by use of thermally regenerable resin - Google Patents

Abstract

The treatment tower of this app. is composed of regeneration, heat exchange and adsorption zone and the continuous ion exchange is attained by loading the thermally regenerable resin from top to bottom of this tower by turns. Ion exchange of an undiluted soln. at adsorption zone and regeneration of ion exchange resin used at regeneration zone are done simultaneously or separately. The part of thermally regenerable resin adsorption ions at adsorption zone or all the resin strata are moved and the resin adsorbed at the top of the tower is continuously loaded.

Description

Continuous ion exchange device using heat regenerative resin

This figure is a schematic explanatory diagram which shows embodiment of this invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous ion exchange apparatus using heat regenerative resins, and more particularly to a continuous ion exchange seam using a single column filled with a bed of heterogeneous heat regenerative ion exchange resin (BED). Here, the heterogeneous ion exchange resin is an ion exchange resin having both a cation and an anion exchange capacity, whereby the ion exchange capacity is regenerated by contact with a hot liquid such as hot water and a loaded resin.

Existing techniques related to this are as follows.

United States Patent 2,719,206-Gilmore: Gilmore showed a single tube continuous adsorber using a downward sorbent bed. Adsorbents include, for example, silica gel, activated charcoal, activated alumina, bauxite and magnesia. There is no mention of exchange resins, however, and the process of the device is directly related to the separation of organic matter. US Pat. Nos. 3,351,549-Block and 3,645,922-Vice et al .: Blocks showed positive amph-oteric resins useful for desalination. The resin is renewable with hot water but its regeneration takes place in a tube separate from the pipe from which the water supplied is desalted. Vise et al. Showed composite-type thermal regeneration resins, where the regeneration is carried out by a backwash technique or by a separate pipe treatment method.

U.S. Patent 3,549,526-Brown: A device is shown here for the use of separate spent and recycled tubes and for solid particle exchange between the two tubes. However, these solid particles were only ordinary ion exchange resins and were not in the form of heterogeneous thermally regenerated ion exchange resins.

U.S. Patent 4,056,471-Fischer et al .: This example shows continuous regeneration but is steam treatment rather than hydrothermal treatment. This invention also relates directly to the regeneration and reactivation of inorganic adsorbents used for the purification of liquid organic compounds. There is also no mention of ion exchange resins and no mention of heterogeneous thermal regeneration ion exchange resins themselves.

These existing techniques have not been able to achieve continuous ion exchange treatment involving both filling and regenerating quantum in a single tube containing thermally regenerative resin. The inventors believe that in order to effectively achieve these points, a regeneration zone must be above the loading zone, and the two zones are separated by a heat exchange zone and a temperature buffer zone so that excessive heat dissipation between the two zones is achieved. It was found that the dispersion should be prevented. At the same time, it was found that the temperature of the regeneration zone should be maintained at a level higher than the temperature of the filling zone. The present invention will now be described in detail.

The thermal regeneration resin used in the present invention is different from conventional ion exchange resins in which ion exchange capacity is regenerated by using chemical reagents such as acid and basic aqueous solution, and is a resin type in which ion exchange capacity is regenerated only by using hot water. In recent years it has become possible for industrial use. (An example of this resin is Amberlite® XD-2, manufactured by Rohm and Haas, USA.)

In treatments involving the use of ion exchange resins regenerated by conventional chemical reagents, the treatments carried out in a fixed ion exchanger may not be carried out simultaneously in the same column, and when two sides are treated, The other side has been suspended. In view of this, continuous mobile phase ion exchangers have been developed and put into practical use. However, such a device has a disadvantage that a separate regeneration tower has to be installed separately from the ion exchange tower, so that the tool is expensive.

An object of the present invention is to practice an apparatus for efficiently carrying out a continuous ion exchange treatment and a regeneration treatment by enclosing a treatment tower made of a filled thermal regeneration resin.

The amount of hot water used for regeneration in the regeneration of heat recovery resin should be minimized in accordance with economic viewpoint.

In the upflow treatment tower, the solution is pushed up to the top of the thermal regeneration resin for complete reaction. For this reason, the flow rate of the solution has a minimum due to the specific gravity and other factors of the heat recovery resin. If the flow rate is below the minimum limit, it is necessary to install a filling station under the regeneration zone of the thermal regeneration resin to send the filling water to a flow rate higher than the corresponding threshold.

Again, it is necessary to install a heat exchanger between the regeneration stand and the filling stand in order to prevent heat from being diffused below the regeneration stand to generate heat loss.

The present inventors installed a heat exchanger in a regeneration tower to achieve the above two objects. It was found in the experiment that a portion of the water used for filling performed the ion exchange treatment (desalting) immediately.

After reviewing the utility of the filling process with the effect of direct ion exchange treatment, the results showed that one treatment tower could perform the ion exchange treatment and the regeneration treatment. The installation of the stage produced a flow rate of the stock solution, which served as a part of filling, and this concept led to the configuration of the present invention.

One of the embodiments of the continuous ion exchange treatment apparatus of the present invention will be described by reference to the desalination treatment.

A thermal regeneration resin layer filled with thermal regeneration resin is formed in one vertical processing tower 2 with a hopper 1 at the top, and in the order from the top to the lower direction in the processing tower 2. A regeneration stand 3, a heat exchange stand 4, and an adsorption stand 5 of a thermal regeneration resin are placed.

The stock solution tube 7 which provided the distributor 6 and attached the valve 11 to the lower end of the adsorption | suction stand 5 will pass through this.

The treatment liquid tube 8 also causes the treatment column 2 to communicate with the upper end of the suction table 5. The hot water pipe 9, which is located at the lower end of the regeneration table 3, reaches a heating deaerator 16 in which a steam pipe 18 is installed, communicates with the treatment tower 2.

The wastewater pipe 10 connected to the heat exchanger 20 communicates with the processing tower 2 at the upper end of the regeneration stand 3. The heat exchanger 20 and the heating degasser 16 communicate with each other by the medium of the heat recovery tube 21 to recover the waste water.

The bottom of the processing tower 2 and the top of the metering hopper 14 are in communication with each other through the medium of the transfer pipe 17 of the thermal regeneration resin which is near the bottom of the processing tower 2 and adsorbed ions. The bottom of the metering hopper 14 and the upper part of the hopper 1 communicate with each other by the transfer pipe 19 provided with the valve 15.

The operation of the present invention will now be described. The action of the thermal regeneration resin in the state where the raw liquid requiring the desalination treatment having a temperature below the temperature of the regeneration hot water by opening the valve 11 is transferred to the adsorption zone 5 by the upward flow through the distributor and regenerated. Is desalted by

The demineralized liquid flows out through the process liquid pipe 8 at the upper end of the adsorption table. At the same time, the hot water for regeneration into the regeneration stand 3 by the hot water pipe 9 is introduced into the tower in an upward flow to regenerate the heat regeneration resin adsorbed by the ions. The wastewater which has completed the regeneration in the wastewater pipe 10 is discharged to the upper portion of the regeneration stand 3. Heat of the recycled waste water passing through the heat exchanger 20 and the heat recovery tube 21 is recovered by the heating degasser 16. Desalination and regeneration are carried out independently of each other.

As described above, after the stock solution and the regeneration water are supplied for a predetermined time, the valve 11 of the stock tube 7 is closed to stop the supply of the stock solution, and the stock solution collection pipe 22 from the branch pipe outside the stock tube 7 is provided. Valve 12 is opened and a predetermined amount of the raw liquid in the processing tower 2 is recovered. Thus, a thermal regeneration resin that adsorbs ions is retained in the lower portion of the adsorption table 5 and is placed under the distributor 6, and the entire thermal regeneration resin layer is sucked downward. Alternatively, the entire thermal regeneration resin layer will be lowered by moving the thermal regeneration resin absorbing the ions through the bottom of the treatment tower 2.

At this time, the backflow prevention device 13 installed between the hopper 1 and the processing tower 2 descends and simultaneously stores the resin in the hopper 1, and the recycled resin falls in the processing tower 2. To be. The valve 12 of the stock solution collection tube 22 is now closed, the valve 11 of the stock solution tube 7 is opened to start the feed of the stock solution, and the backflow prevention device 13 stops the drop of the thermal regeneration resin. I come up to make it.

Part of the thermal regeneration resin adsorbed by the ions falling below the stock distributor 6 flows through the feed pipe 17 by the pressure of the stock solution, reaches the metering hopper 14 and is stored there. By opening the valve 15 of the transfer pipe 19, the heat regeneration resin of the metering hopper 14 is stored in the hopper 1, and is subsequently filled in the treatment tower 2. In general, the hopper 1 has a larger content than the metering hopper 14, and is used for supplying newly replenished thermal regeneration resin and separating the pulverized resin. The heat exchange zone 4 is regenerated to cool the resin having high heat, and at the same time, the buffer zone between the regeneration zone 3 and the adsorption zone 5 is exerted.

Conditions such as the flow rate and temperature of the stock solution and hot water for regeneration, and the time taken for the feed and recovery of the stock solution, are appropriately set to suit the performance of the heat recovery resin, the quality of the stock solution, and other similar processing conditions. In addition, the diameter and length of the treatment tower, the length of the regeneration stand 3, the heat exchange stand 4, the suction stand 5, and the like are appropriately set under conditions such as the performance of the thermal regeneration resin. In the above method, the regenerated and cooled thermal regeneration resin is always supplied to the adsorption table 5 in the processing tower 2.

Since the thermal regeneration resin having the highest adsorption performance is always supplied to the upper portion of the adsorption table 5, desalination and regeneration treatment are efficiently performed in one treatment tower 2. In addition, demineralized water can be continuously obtained while stopping the recovery of the stock solution.

Moreover, in the present invention, the heat exchange zone 4 is used to prevent heat loss from being caused by the diffusion of heat of the regeneration hot water and, if necessary, the heat exchanger 20 to recover heat from the regeneration waste water. Therefore, the thermal efficiency is increased, and the ratio of the amount of circulation of the thermal regeneration resin of the conventional regeneration hot water is reduced to 1/2 to achieve a thorough regeneration effect. Thus, the use amount of hot water for regeneration is greatly reduced. The heating deaerator 16 suitably used for treating the regeneration hot water has an effect that contributes to extending the life of the thermal regeneration resin by exerting the deoxygenation effect.

In addition, in the present invention, since one treatment tower of the ion exchange treatment apparatus is sufficient, the piping and valve control mechanisms are required for each of the two-minute towers in the continuous mobile phase ion exchange treatment apparatus in which the above-mentioned adsorption tower and the regeneration tower are separately installed. In comparison, the cost of eliminating the ion exchange apparatus itself is reduced.

In addition, the above 1 minute tower method is extremely simple to operate, which simplifies complex plant management and maximizes the reduction of the processing liquid cost.

Compared to the two column treatment tower, the method of the present invention reduces the loss of the solution in the recovery and transfer of the solution since the reconsolidation of the resin layer in the treatment column causes almost half the number of resin transfer times outside the treatment tower. little.

At the same time, there is less chance of crushing the resin due to wear. Therefore, this method has an advantage of improving solution utilization and extending resin life.

Now, an embodiment of the present invention will be described.

Example 1

A 2m regeneration stand is formed at the top of the treatment tower having a height of 7m and a diameter of 0.25m, and a heat exchanger of 1m is formed immediately below, and a 2.5m suction zone is formed thereon. In the thermal regeneration resin, Amberlite (registered trademark)

XD-2 (available from Rohm and Haas, USA) was used. In this device, continuous desalination was carried out by the method described below.

Cyclic thermal recycled resin per unit time (sic)

In other words, the internal capacity of the weighing hopper was 120ℓ, the amount of hot water for regeneration was 60ℓ, the temperature of hot water for regeneration was fixed at 90 ℃, and the stock solution at 16.5 ℃ containing 1,100ppm of dissolved salt concentration (using CaCO ₃ ) was 920ℓ per hour. Treated. The result was demineralized water with a concentration of 350 ppm of CaCO ₃ . Regeneration water and stock solution were supplied in an upward flow and the resin was dropped into the treatment tower at the same interval of 3 minutes.

The stock solution was used as hot water for regeneration.

Heat from the regeneration wastewater was recovered using a plate heat exchanger, and the stock solution was preheated to 57 ° C with this recovered heat, and heated to 90 ° C by injecting steam. The hot water thus obtained is degassed and used.

As a result, desalting was carried out in a ratio of about 6.5 milligrams per calorie of heat per 1 KCal to 1 liter, 0.115 equivalents of thermal regeneration resin. After 4000 hours of operation, the grinding speed of the thermal regeneration resin is less than 1% in the apparatus of the present invention, compared to about 2% of the conventional two- tower processing tower at a content ratio of 50 mesh.

Claims (1)

A device for filling ionized thermally regenerative resin by continuously regenerating a regeneration table, a heat exchanger, and an adsorption column in an order from the top of the tower to a downward direction, and performing ion exchange treatment and regeneration of the stock solution in the adsorption column. The regeneration of the ion exchange resin by the use of hot water in the bed is carried out simultaneously or separately, and the portion of the heat regenerated resin adsorbing the ions in the adsorption table falls below the feed solution supply position at the bottom of the treatment tower, or the entire resin layer is moved downward. Continuous ion exchange device using a thermal regenerative resin, characterized in that the resin to be ion-adsorbed to the upper portion of the inside continuously.

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