JPS63107753A - Method for separating and transferring ion exchange resin - Google Patents

Abstract

PURPOSE:To enhance the quality of treated water by reducing a chlorine type anion resin formed by reducing an anion resin remaining at the time of distribution and transfer as low as possible, by properly arranging a transfer sluicing pipe and a pair of resin transfer pipes in a separation tower. CONSTITUTION:In separating and transferring the strong basic anion exchange resin (hereinbelow referred to as SBR) 2' low in specific gravity remaining on a strong acidic cation exchange resin (hereinbelow referred to as SAR) layer 1 high in specific gravity, the transfer sluicing pipe 7 traversing the center of a tower provided below a boundary line and resin transfer pipes 8 having opening parts 8', 8'' in positional relation so as to cross said pipe 7 crosswise are provided. The resin layer SAR 1 having high specific gravity is brought to a flowable state by backwashing water and water is further blown off upwardly from the pipe 7 provided in the intermediate part of said resin layer. By this method, the resin SBR 2 having low specific gravity is gathered to the opening parts 8', 8'' of the transfer pipes 8 to be transferred.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a pure water or ultrapure water production device, and particularly to a condensate desalination device for condensate treatment in a thermal xPks nuclear power plant.

[Conventional technology]

The mixed resin layer of 28IL type ion conversion resins, especially strong acidic cation conversion resins (hereinafter referred to as 8R) and strong basic anion father conversion resins (hereinafter referred to as 8BR), is suitable for the production of pure water and ultrapure water. The device's polyurethane and.

Condensate desalination equipment for thermal power and nuclear power plants! 1 is essential. Conventionally, the water quality required for the after-water treatment of a PWR nuclear power plant is most stringent as shown below.

Na″ concentration α02 ppb or less Ct-1 (L 05 ppb or less These ions 111 degrees are as low as possible.

The amount of these ions leaking from the mixed resin layer is controlled by the proportion of salt type resin in the mixed resin layer, except for the inlet water quality conditions and the operating conditions (LV, etc.) of the mixed resin layer. In other words, the higher the proportion of R-Ct (chlorine type anion resin) and R-Na (natrichum cation resin), the higher the
The leakage of t- increases. These R-Na, R-Ct
The cause of generation is Na', CL″″ derived from raw water.
Considering the following, the main reasons are as follows.

R-Na: SB due to incomplete separation and transfer of BAR and 8BR
N mixed in the R layer and 7'j8AR is a regenerating agent for 8BH.
Formed on contact with aOH.

R-C1: +11 Impurities in regenerant NaOH (NaC
1). (2) Similar to R-Na, SBR, which is incompletely separated and remains in the BAR layer, is generated when it comes into contact with HCt, which is a BAR regenerant.

Methods to reduce R-Na production have been extensively researched, and the main cause of 0R-C2 production (1), which has been solved by Patent No. 1027750, has been reduced by improving the quality of NaOH. ing. Regarding (2), the separation and transfer is incomplete in the conventional technology, and 8AR/@rc total 8B
8BR of about 1 to 2% HO remains, and this is accumulated every time it is regenerated, so in an equilibrium state, R-C1 of the mixed resin layer is the total S
It has a value of 20 minus BH.

A conventional resin separation and transfer method will be explained with reference to FIG.

The resin 1s is separated into two layers, AR layer 1 and 8BH layer 2, by backwashing, and 1LV of sluging water is introduced from the current sluicing water pipe 3 into the lower part of the column at a rate of about 2.5 m/hour, while slightly fluidizing the BAR layer 1. Pressurized water or pressurized air is introduced from the pressurized water t4 in the tower upper pan or pressurized air from the pressurized air 'li6 and transferred to the SBR 7 anion regeneration tower. In FIG. 8, the opening of the transfer pipe 8 during transfer is provided on the central axis of the tower or in the wall of the tower. In some cases, the entire trough is used. Further, the height of the opening is usually set to be slightly below the interface between the two resin layers.

When performing such a transfer, as shown in Figure 9 (,5B
It is unavoidable that R2' remains in an amount of several to several dozen.

The reason for this is that the closer the 8BR is to the tower wall, the longer it takes to reach the opening of the transfer pipe 8, during which time the resin near the opening is transferred, and the resin surface becomes flat due to sluicing water from the lower part of the tower. 9. This is because a certain distance occurs between the opening and the surface of the resin layer, and SBR is no longer transferred.

This phenomenon occurs in the same way even if the amount of sluicing water is increased, the expansion rate of the BAR layer is increased, or the height and shape of the opening are changed, and complete separation and transfer of 98BH is not achieved.

These remaining 7tSBR come into contact with HCt of the SAR regenerant to generate R-CL.

[Problem that the invention seeks to solve]

The present invention solves the above problem (2), and aims to reduce the amount of SBR retained in the separation and transfer method as much as possible, and improve the quality of the treated water during ion exchange.

[Next method to solve the problem]

The present invention utilizes a column filled with two types of ion exchange resins with different specific gravity, and after the ion exchange resin is separated into 1i-2 layers by backwashing, pressurized water or pressurized air is discharged from the upper part of the column, and sluicing water is discharged from the lower part of the column. Most of the ion exchange resin 1 with low specific gravity is introduced and transferred by a resin transfer pipe, and after the transfer, a small amount of ion exchange resin with low specific gravity remaining on the ion exchange resin layer with high specific gravity is further separated and transferred. In the method, a transfer sluging pipe is placed across the center of the prisoner tower below the boundary surface of the ion exchange W fat layer of ←bottle ÷ nozzle stand 281I class, and is placed crosswise with the center of the transfer sluging pipe. Resin transfer pipes are provided on both sides and near the tower wall in an intersecting positional relationship, and (B) water is transferred upward from the transfer sluging pipe while keeping the ion exchange resin with a large specific gravity in a fluid state. A method for separating and transferring an ion exchange resin, characterized in that the ion exchange resin with a small specific gravity is transferred to the opening of the resin transfer tube by blowing, or the ion exchange resin is transferred by the resin transfer tube after being transferred, In order to solve the problems of the separation and transfer method, we conducted intensive research using a practical-scale column with a large diameter, and as a result, we came up with an invention.

Hereinafter, the present invention will be explained in detail based on the drawings.

As shown in Fig. 1, in separating and transferring S B R2' with a low specific gravity remaining on 5ARN11 with a high specific gravity, the present invention is provided with a transfer system installed at the lower part of the boundary surface and crossing the center of the next column. The resin transfer pipes 8, 8 with openings 8' and 8'' metal are provided respectively in a criss-cross position to intersect with the sluging pipe 7, and a low flow rate reverse flow is carried out from the lower part of the tower through the pipe 3. While introducing washing water to bring the BAR into a fluid state,
By blowing water upward from the transfer sluging t7, SBR gathers around the openings 111s8' and 8' of the resin transfer pipes 8 and 8, as shown by diagonal lines in FIG. However, it will be transferred. In addition, 5
is the backwash water discharge pipe.

That is, in the present invention, the openings of the p8BR't-transfer pipes 8.8 @8', 8a are brought into the 8ARt-flowing state and the water is blown upward from the center of the BAR layer.
'It was designed to be collected in a large area.

The most important item in this invention! This is the flow rate of water that is blown upward from the transfer sluging pipe. If this flow rate is too high, the flow of the 8BR resin layer 2' will flow toward the openings 8', 8', but will hit the tower wall and become a reverse flow. When this reverse flow occurs, the 8BR that once gathered will be dispersed again. As a result of experiments, it was found that a very small flow rate of LV [L5 to 2 m/hour] is good.

Furthermore, we have discovered that there is almost no risk of reverse flow occurring if water is blown out from the transfer sluging pipe 7 in a continuous manner. Water spray for 5-30 seconds, pause 15
If this is done continuously for ~60 seconds, the resin surface directly above the transfer sluging IT7 will rise slightly as shown in FIG. 6. In order to do this thoroughly, S B
R2' becomes wavy and moves toward the opening 91. The best condition is to make it almost disappear near 811, and by doing this, the 7th
As shown in the figure, the SBR is connected to the openings 8' of the resin transfer pipes 8, 8.
When the resin 2' gathers at the resin transfer pipe opening 81.811 as shown in FIG. 7, the resin transfer pipe valve 9t of the resin transfer pipes 8,8 - It is possible to open and concentrate and transport nine SBRs at any time.

It is preferable to continue blowing out water from the transfer sluging pipe 7 during transfer.

That is, the present invention has the following features: 1) A resin layer 5ARI having a large specific gravity is brought into a fluid state by backwashing water, and 2) A sluicing '1 for transfer is provided in the middle of the resin layer.
Further water is blown to the top from 7, and 3) the resin 8BR2 with low specific gravity is transferred as shown in Fig. 7! 8.8 opening 8'
, 8', and 4) then transfer. This is a combination of the six steps 1) to 4). Even if these series of steps are performed only once, it is preferable to repeat the above steps several times the next time the money is transferred. Opening s8' of resin transfer pipe 8.8.

As shown in #8, it is installed at a position perpendicular to the center of the transfer sluging pipe. If this shift occurs, the opening will shift from the center of the concentrated SBH, making it difficult to transfer completely. The height of the opening may be determined in consideration of the backwash development rate of 8AR#1 so that the BAR remaining after transfer is quantitative. Normally, when the backwash expansion rate is increased, errors tend to occur in the quantitative performance of 8AR, so it is preferable to set the backwash fluid to LV3 to 5 m/hour. The shape of the opening is 8BR as shown in Figure 7.
(7) A curved tube shape may be used depending on the concentration state.

The position of the transfer sluicing t7 is 'aK lipolipidemic interface 5
00 to 600 W, and if this distance is too small, the water will blow out or boil, and if it is too large, the water will spread out and the effect will be reduced. The number of transfer slugs t7 may be one as shown in FIG. 2, or two as shown in FIG. 3. Uniform dispersion of water t-1: 1M When the diameter of the column is large, it is preferable to provide two columns as shown in FIG. In any case, SBH toward the two openings.
It is fine as long as it can produce a flow.

Below, each step of unexploded BA will be explained in detail using a separation column of a condensate desalting device as an example.

FIG. 4 is an explanatory diagram showing an example of an embodiment of the present invention.

Items with the same names are given the same reference numerals as in Figures 1 and 8. 0 The mixed resin transferred from the demineralization tower (not shown) is transferred to the separation tower 10 through the backwash water flow valve 11 and the reverse water flow valve 11. The wash drain valve 12 is opened and the drain valves 11 and 12 are closed after the backwash portion I@l has been sufficiently performed at 578 to 10 m7 o'clock. After settling, open the sluicing water valve 15'Ik and introduce sluging water at 7:00 LM (L7 ~ 1.5 m), and open the pressurized water valve 16 at the top of the tower and the square 9.9 of the resin transfer pipe 8.8. And most of 5BRZ
is transferred to an anion regeneration tower (not shown).

When the sluicing water flow rate is reduced to LVα7~t5m7, the BAR layer does not flow substantially and the SB
Only the R layer is slightly fluid. When such a transfer is performed, the resin surface is inclined from the center of the tower toward the openings of the resin transfer pipes 8, 8, but if it is made uniform, the resin surface will be inclined at the openings 8', 8' as shown in FIG. is located within the BAR layer. When this flow rate is increased, the BAR
When the backwash expansion rate of the layer is large υ, more BAR is transferred to the anion regeneration tower, and when the distance t' between the opening and the layer surface is small as shown in Fig. 5, the remaining 8BR2 is completely removed. Not suitable for transport.

Then fi? ,? , sluicing water valve 15 and pressurized water valve 16'Ii - closed, backwash drain valve 12, low flow backwash valve 1
4 open L, LV & 5~45m SA at 7 o'clock
One layer is in a fluid state. The remaining 5BR1 is then transferred by the method of the invention. It is important to control the development of low-flow backwashing 9P14 so that a constant SAR development rate is always achieved, taking into consideration water temperature, etc.

Next, the transfer sluicing water valve 15'Ik is opened, and the LV
(Transfer sluging water is introduced through the transfer sluging T7 at a rate of L5 to 2 m/hour, and is blown out at the same time at the top.

Then, as shown in FIG. 6, the resin layer at the blowout part swells up, and a flow of 8BH as shown in FIG. 7 is created, and 8BR gradually gathers at the opening. This step may take about a5 to 2 minutes.

Then close 9P12, valve? , 9. 16t-open, and the opening ftBK is collected and the next SBR't'' is transferred, and the sluging water 1t7 for transfer may be continuously blown out into the sluging water 1 for spreading transfer, but if the flow velocity is high, the tower wall In order to avoid this danger, it is preferable to blow out the air intermittently.

If the air is blown intermittently for 5 to 50 seconds with a pause of 15 to 60 seconds, the state shown in FIG. 7 can be easily achieved even if the flow rate is increased to LV 1.5 to 2.5 m at 7 o'clock.

By repeating such transfer several times, the remaining 8BR
is completely transferred to the anion regeneration tower.

The repeated steps t are summarized as follows.

Valve in open state Time backwash separation 11,12 5~5
Min8BR″f-a’) 12,14,15 1~
2 minute transfer (1) (Wow, process transfer (2) (transfer) 16, 9, 14, 15
1 to 2 minutes In this embodiment, a method of moving the material to the opening and then transferring it from the transfer tube is shown, but it is also possible to transfer the material while moving it.

In order to clarify the effects of the present invention, comparative examples and examples will be described below.

Comparative Example 1 (Conventional method) Dowex TG 650C (registered trademark) 4500 was used as SAR in a separation column with an inner diameter of 1800φ and a height of 5000mm.
A mixed resin of 2000 t of Dowex TG 550A (registered trademark) was heated as t%SBR, and backwash water was introduced into the lower part of the column at a LV of 10 m/hour to separate the resin into a t-2 layer.

Next, sluicing water from the lower part of the tower t-Lv2.5
m Introduced at 7 o'clock, and at the same time pressurized water from the top of the tower t L V
4 m It was introduced at 7 o'clock. The resin transfer pipe had one opening on the central axis of the tower, and had a diameter of 75φ. Also, the position of the opening is set so that it is 100 fins below the resin interface.

The 8BR remaining after the transfer was lost in α5 to α6 of all 8BR.

Method for investigating residual 8B'H After transfer, backwash at L V 10 m/hour for 40 minutes, scrape off all 6 8BR stuck on the surface layer, and measure the volume.

Example 1 A tower of the same size as Comparative Example 1 was used. After separating the resin into two layers in the same manner as in Comparative Example 1, the sluicing water from the bottom of the column was L V 1.2 m At 7 o'clock, the pressurized water 'kL from the top of the column was
The bulk of the 8BH was transferred by introducing at V4 m/hr, followed by the transfer of the whistle SBH.

There were two openings for the resin transfer 11 as shown in FIG. 4, and the other conditions were the same as in Comparative Example 1.

Transfer of residual @8BR> Low-flow backwash water f L V 4 m Introduced at 7 o'clock, BA
Rl - Let it be a fluid state and then. Furthermore, water was continuously blown out for 1 minute across the center of the tower from a transfer sluicing torpedo (one) installed at the lower part of the 450 fin on the resin separation surface at a LV of 1 m/hour, and then the transfer was performed for t-1 minute. . Then LV5m/
After performing backwash separation for 3 minutes at We transferred the remaining SBH to Mr. U. Repeat these steps three times.9. After combing, only the above-mentioned transfer was performed for t-10 minutes.

The remaining 8BRs were α02 to α035 whispers of all 8BRs.

Example 2 In Example 1, the sluicing water for transfer was
9. The residual SBH was transferred in the same manner as in Example 1, except that the procedure was repeated for 5 seconds and then for 15 seconds. residual SBR
was IIL025% to α015 of all 8BRs.

Example 3 Using the same method as in Example 1, the filling resin was made to have the following configuration.

S A R: Dowez H()R-W2B B R
: Dowex T() 550A The 8BRs that remained were a total of 13BRs α02 to α035.

〔Effect of the invention〕

As stated above, according to the method of the present invention, residual SBR can be reduced to 1/15 to 1/40 of the conventional method. Therefore, the amount of R-CL (chlorine type anion eR fat) produced can be reduced, and the quality of treated water can be improved. Great improvement.

[Brief explanation of the drawing]

FIG. 1 shows ion conversion 11j for explaining the method of the present invention.
A vertical schematic diagram of an example of an MFI separation column, Figure 2 is A of Figure 1.
-A cross-sectional view taken along the line, Figure 3 is a diagram showing the following case where two sluicings for transfer are installed in Figure 2, and Figure 4 is a diagram showing the case of misfire F! A schematic cross-sectional view of the ion exchange resin separation column used in the present invention to explain A in more detail, FIG. 5 is a companion view illustrating the opening 111 of the resin transfer pipe, and FIGS. 6 and 7. Diagram 8 for explaining the flow (moving state) of ion exchange resin with a light specific gravity when the resin is further separated.
The figure shows the conventional ion exchange resin separation method IkM5! The following is a schematic vertical cross-sectional view of an example of a resin separation column, and FIG. 9 is a diagram for explaining the state of a light resin with a ratio of 1 remaining in a small amount on the ion-containing fat layer with heavy specific gravity. be. 1... SAR layer, 2... SBR layer, 3... Sluicing water pipe, 4... Pressurized water pipe, 5... Backwash drain pipe,
6... Pressurized air pipe, 7... Resin transfer sluicing pipe, 8... Resin transfer pipe, 9... Resin transfer valve, 10...
... Ion exchange resin separation tower, 11 ... Backwash water inflow valve,
12... Backwash water υF output, 13... Sluicing water valve, 16... Pressurized water valve, 14... Low flow rate backwash valve, 1
5... Transfer slugging valve patent applicant Ebara Infilco Co., Ltd. Ebara Urasakusho Co., Ltd.

Claims (1)

[Claims] 1. In a tower filled with two types of ion exchange resins with different specific gravity, after the ion exchange resin is separated into two layers by backwashing, pressurized water or pressurized air is supplied from the upper part of the tower to the lower part of the tower. By introducing sluicing water, most of the ion exchange resin with low specific gravity is transferred through the resin transfer pipe, and after the transfer, a small amount of ion exchange resin with low specific gravity remaining on the ion exchange resin layer with high specific gravity is removed. In the method of further separating and transferring the In this regard, resin transfer pipes having openings on both sides and near the tower walls are provided, and (B) water is transferred upward from the transfer sluging pipe while keeping the ion exchange resin having a large specific gravity in a fluid state. A method for separating and transferring an ion exchange resin, characterized in that the ion exchange resin having a small blowout specific gravity is transferred to the opening of the resin transfer tube, or is transferred by the resin transfer tube after being transferred. 2. The method according to claim 1, wherein the transfer water is intermittently blown upward from the transfer sluging pipe.