JP2001293471A - Purified water making device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a purified water making device solving the problem of pyrogen. SOLUTION: This purified water making device makes purified water filtered and purified with a reverse osmosis module 1 provided with a reverse osmosis membrane. A front stage of a booster pump 15 for feeding water to the reverse osmosis module 1 is connected to a delivery pipe line 30 of the purified water purified with the reverse osmosis module 1 through a circulation path 33 provided with a back pressure valve 35, and as the booster pump 15, a pump is used of variable transfer quantity type changing the transfer quantity in accordance with pressure of the purified water in the delivery pipe line 30. This pump directly feeds the purified water without storing it in a feed tank, and the variation of the use quantity of the purified water is coped with by circulation of the purified water and also changing the transfer quantity of the booster pump 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an apparatus for producing purified water, and more particularly to an apparatus for producing purified water which can be suitably used for producing purified water for artificial dialysis.

[0002]

2. Description of the Related Art FIG. 2 shows a conventional apparatus for producing purified water for artificial dialysis. This is a process in which raw water, which is city water (tap water), is passed through a prefilter 11, an activated carbon filter 12, a water softener 13, and a check filter 1.
4, the water is sent to the reverse osmosis module 1 equipped with the reverse osmosis membrane by the pressurizing pump 15, and the purified water exiting the reverse osmosis module 1 is stored in the supply tank 2 and the purified water in the supply tank 2 is removed. It is supplied for artificial dialysis by the supply pump 20. At this time, according to the fluctuation of the amount of purified water used,
A part of the purified water sent out by the pump 20 is returned to the supply tank 2 through the circulation path 24. In the figure, reference numeral 25 denotes an ultraviolet germicidal lamp arranged in the supply tank 2.

[0003]

Here, the purified water in the supply tank 2 is dechlorinated water which is in a state where various germs are easy to propagate, and a part of the purified water is circulated. Although the residence time is likely to be long and bacteria can be killed by the germicidal lamp 25, bacterial pyrogen (endotoxin) and non-bacterial pyrogen are liable to be mixed into purified water. When pyrogen is mixed into purified water for artificial dialysis, it causes symptoms such as fever in dialysis patients.

[0004] The present invention has been made in view of such a point, and an object of the present invention is to provide a purified water producing apparatus which can solve the problem of pyrogen.

[0005]

SUMMARY OF THE INVENTION The present invention provides a purified water producing apparatus for producing purified water filtered and purified by a reverse osmosis module having a reverse osmosis membrane. The former stage and a discharge pipe for purified water purified by the reverse osmosis module are connected by a circulation path provided with a valve that opens and closes according to the pressure in the discharge pipe, and the pressurized pump is connected to the inside of the discharge pipe. It is characterized in that a feed rate variable type that changes the feed rate according to the purified water pressure is used.

[0006] Purified water is directly sent out without being stored in a supply tank, and fluctuations in the amount of purified water used can be accommodated by circulating the purified water and changing the feed amount of a pressurizing pump. It was done.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to an example of an embodiment shown in an apparatus for producing purified water for artificial dialysis. In FIG. 1, raw water which is city water (tap water) is raw water. Pressurized by the pump 10 and sent out to the activated carbon filter 12, the water softener 13 and the security filter 16 side,
Water passing through these and reaching the water supply pipe 18 is subjected to a reverse osmosis module 1 having a reverse osmosis membrane by a pressure pump 15.
Sent to The purified water exiting the reverse osmosis module 1 is not stored in a supply tank, but is stored in a supply tank, passes through an ultraviolet sterilizer 26 and a UF membrane 27 for endotoxin cutting, and is used for artificial dialysis. Supplied to The concentrated wastewater in the reverse osmosis module 1 is used for cooling the drive motor of the pressurizing pump 15 by the drainage pipe 31, and then drained to the drain 5.

Here, the downstream side of the ultraviolet sterilizer 26 in the discharge pipe 30 and the water supply pipe 18 upstream of the pressurizing pump 15 are connected by a purified water circulation path 33, Piping 31 and water supply piping 1
8 is connected by a concentrated water circulation path 34, and a part of the concentrated water is returned to a stage preceding the pressure pump 15. In the figure, P1 to P6 are pressure sensors, C1 and C2 are water quality sensors, F1 and F2 are flow rate sensors, and T1 is a temperature sensor.

A back pressure valve (relief valve) 35 is provided in the purified water circulation passage 33 to open when the water pressure in the discharge pipe 30 becomes higher than a predetermined value. In addition, here, a pump whose pumping capacity is variable is used as the pressurizing pump 15 and the pumping capacity is adjusted according to an output value of a pressure sensor P6 that detects purified water pressure in the discharge pipe 30. It is set to change.

In this purified water production apparatus, raw water reaches the reverse osmosis module 1 through the activated carbon filter 12 and the soft water device 13 as described above, and the reverse osmosis membrane 1 of the reverse osmosis module 1
The purified water that has passed through 0 is supplied directly to the artificial dialysis through the discharge pipe 30 and is used for the artificial dialysis without being stored in the supply tank that caused the contamination of the pyrogen. The problem caused by the patient's pyrogen can be solved.

Here, the absorption of the fluctuation in the amount of purified water used in the conventional supply tank is performed by circulating the purified water through the purified water circulation path 33 and changing the supply capacity of the pressurizing pump 15. ing. When the amount of use decreases and the pressure in the discharge pipe 30 increases, the back pressure valve 35 opens and excess purified water is supplied through the purified water circulation path 33 to the pressure pump 1.
5, and reduces the feeding capacity of the pressurizing pump 15. If the amount of use increases, at this time, the back pressure valve 35 closes to supply the entire amount of purified water for artificial dialysis and to increase the supply capacity of the pressurizing pump 15. During operation, the pressurizing pump 15 always operates, and performs a continuous operation of constantly flowing water through the reverse osmosis module 1.

The supply capacity of the pressurizing pump 15 is changed by detecting a difference between a preset pressure and a pressure of purified water in the discharge pipe 30 detected by the pressure sensor P6, and pressurizing according to the difference. It can be performed by changing the power supply frequency of the power supply to the motor of the pump 15, and the control at this time can use proportional control, proportional / integral / differential control, etc. This may be dealt with by changing it.

The purified water circulation path 33 and the discharge pipe 30
Are communicated through the back pressure valve 35, but the back pressure valve 35
Instead, an electromagnetic valve that is opened and closed by the output of the pressure sensor P6 for detecting the pressure in the discharge pipe 30 may be used.

The pressure of the purified water is preferably set at 0.2 to 5 kg / cm ² , more preferably at 1 to 3 kg / cm ² .
If the pressure is too low, it is difficult to sufficiently supply purified water to the next step. If the pressure is too high, a large-capacity pump 15 is required, and the temperature of the purified water rises due to large heat generation. Problems such as an increase in energy consumption occur.

[0015]

As described above, according to the present invention, in a purified water producing apparatus for producing purified water filtered and purified by a reverse osmosis module equipped with a reverse osmosis membrane, a pre-stage of a pressure pump for feeding water to the reverse osmosis module is provided. And a discharge pipe for purified water purified by the reverse osmosis module, connected by a circulation path having a back pressure valve, and a feed rate according to the purified water pressure in the discharge pipe as the pressurizing pump. Since the variable feed rate variable type is used, purified water is directly sent out without storing it in the supply tank, which causes the contamination of pyrogen. Problem can be solved.
The fluctuation in the amount of purified water used due to the abolition of the supply tank should be dealt with by changing the feed rate of the pressurized pump for circulation of purified water through the purified water circulation path communicating with the discharge pipe via the back pressure valve. Can be done.

[Brief description of the drawings]

FIG. 1 is a piping diagram of an example of an embodiment of the present invention.

FIG. 2 is a piping diagram of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reverse osmosis module 15 Pressure pump 30 Discharge pipe 33 Circulation path 35 Back pressure valve

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihisa Hohana 3-7-9 Shindaka, Yodogawa-ku, Osaka Mikuni Kikai Corporation F-term (reference) 4C077 AA05 BB01 DD14 KK11 NN20 4D006 GA05 GA05 GA06 JA53A JA56A JA57A JA58A JA65A KA02 KA03 KA16 KA52 KA55 KA57 KA63 KA71 KB04 KB11 KB12 KB14 KD19 KE03Q KE04P KE07P KE08R KE12P KE13P KE16P KE22Q KE23Q PA01 PB06 PB54 PC44

Claims (1)

[Claims] In a purified water producing apparatus for producing purified water filtered and purified by a reverse osmosis module having a reverse osmosis membrane, the purified water is purified by a pre-stage of a pressure pump for feeding water to the reverse osmosis module and a reverse osmosis module. The purified water discharge pipe is connected to a circulation path having a valve that opens and closes according to the pressure in the discharge pipe, and the feed rate according to the purified water pressure in the discharge pipe as the pressure pump. A purified water production apparatus characterized by using a variable feed rate type for changing the amount of water.