JPS60175504A - Method for washing membrane separation apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Field of application between shafts] The present invention relates to a method for cleaning a membrane separation device, and in particular, a method for easily and reliably removing contaminated qIB deposited or attached to the olfactory membrane surface attached to a membrane separation device. The present invention relates to a cleaning method for a membrane separation device that can be peeled and removed.

[Conventional technique 1] In recent years, reverse osmosis (RO) has been used in various water treatment fields such as wastewater treatment, seawater desalination, and pure water production.

Membrane separation devices with built-in selectively permeable membranes such as ultraviolet filtration (OF) membranes or fil ffi filtration membranes are widely used.・This membrane separation device consists of two chambers separated by membranes. Ten thousand (
The stock solution to be treated is introduced under pressure into the stock solution supply chamber (stock solution supply chamber), and the treated water is taken out from the other chamber (processing order 1).

The membrane installed in the membrane separator depends on the shape of the element.
It is roughly divided into flat plate membrane, tube type membrane, vortex type membrane, hollow fiber type membrane, and fold type membrane, and its materials include r[, -6K, vinegar tit cellulose, and polysulfone.

Polyenalene, polypropylene, polyacrylonitrile, polyamide, polyvinyl chloride, polyvinyl alcohol, polyimide, polyvinyl acetate, and the like are used.

Membrane separation equipment v By operating for a long time, the M content in the stock solution increases.
Inorganic QA negative or organic substances such as nulimes, etc., adhere to the membrane surface and cause contamination (fouling).As a result, membrane contamination occurs.

■ Membrane surface is closed and permeated water volume is low (lower water collection volume)
, ■ The differential pressure at the entrance and exit of the membrane separation device increases, and the pressure difference against the membrane element increases (differential pressure increase).

■ In order to obtain a certain amount of permeated water, it becomes necessary to increase the raw water pump pressure (increase in raw power consumption), ■ the quality of the treated water is low, and ■ the film life is shortened due to contamination.

Various disturbances occur and reduce the capacity of the membrane 11ill device.

Therefore, in order to recycle the membrane separation equipment, the membrane is cleaned with chemicals such as rice, alkali, oxidizing agents, reducing agents, chelating agents, and enzymes to remove the membrane deposits. The method of removal is adopted in a negative manner.

However, in the rltiIL and usual llc# methods such as vortex@ type membrane elements, the differential pressure recovery effect is often insignificant. The differential pressure is 4CJ! ! When restarting the system, a sudden rise in differential pressure occurs, and it becomes necessary to increase the operating pressure of the device in order to secure permeate water. Further, problems such as deformation of the membrane element will occur. (II'i is particularly noticeable when such fictitious objects and membrane deposits are mainly slime). This is thought to be because the Kanzen type cannot sufficiently remove the taste of the φ and membrane-attached N substances due to its structure, which does not cause a considerable amount of cross-flow. For this reason, a method of mixing gas into the bubbles 1 during cleaning using gas generation #ct has been considered, but the equipment and operations would be complicated and it would not be an effective method.

A method has also been proposed (Japanese Patent Publication No. 55-37288) in which the polluted reverse permeation of the pond is washed with a hydrogen peroxide bath and the deposits are removed by applying pressure fluctuations. Even if the pressure inside the module is short-lived, sudden vomiting may cause the stool to peel off from the support or shake the entire device, causing deterioration of the container and damaging the device. This may lead to the weakening of the FC9, or the problem of the FC9 due to the 4il failure on the instrumentation.
This cannot necessarily be said to be a satisfactory method.

[Object of the invention] The present invention was conceived in view of the above-mentioned circumstances.
The aim is to provide a method for a membrane separator that can remove contaminants and egg matter deposited and adhered to the membrane of the membrane separator in a very immature manner.

[Structure of the invention]

In order to achieve this objective, the Ministry of the Invention has carefully studied the method of cleaning the membrane and carried out cleaning using an anti-detergent agent to make it easier for contaminants to peel off from the book. , fp
There is a method in which a material that decomposes the agent and generates air bubbles is added, and the air bubbles are used to selectively remove the contaminants.
We have discovered that the door is simple and easy to use, and that it is extremely effective for cleaning spiral membrane separation devices, and have arrived at the present invention.

That is, the present invention is directed to a method for cleaning a membrane separation device, characterized in that a peroxide-based liquid is supplied to a membrane separator (tcfIL), and a catalase-containing liquid is supplied at a second time.

The present invention will be explained in detail below.

In the uninvented cleaning method 2, first, a hydrogen peroxide-containing liquid is supplied to the membrane separator. Hydrogen perbide containing liquid
[20! a & 0.01~10 jILfi 16
．． Preferably, a 0.05 to 3 weight aqueous solution is suitable.

A pRrt of 5 to 9 for this solution is preferred.

To pass the 4T solution containing hydrogen peroxide, first supply the solution containing superoxide water'JA to the washing tank, first circulate the hydrogen peroxide containing solution through the chamber and the membrane separation device using a pump, and then The hood and the peroxide-based liquid are allowed to come into contact with each other in the apparatus with a long diameter. The conditions for passing the hydrogen peroxide-containing liquid are preferably such that the pressure is below the normal operating pressure, the water level is 50 to 200% of the normal operating water tray, and the contact time Fi is 15 to 120 minutes. Further, the standing contact time is preferably 1 to 30 hours, preferably 6 to 24 hours, and the mixture is kept at 9° for a period of time of 11 hours, and the mixture is circulated through the hydrogen-containing M ridge. At this time, catalase, which is a hydrogen peroxide-containing shell, is added to the hydrogen peroxide-containing mortuary solution. Addition of camerase-mμ,
Catalase # [is 0.1-51'9/1. Good 1 L (
H0.5~1.5W/J! It is preferable to set the value to b j . The pressure during the initial liquid circulation as described above should be about the same as that of the water dish, and the monkey contact time r.
J15 to 60 minutes is preferable.

When the process is completed, the water is flushed with water and the inside of the device is sufficiently filled with water. The water flushing conditions are as follows: the pressure is below the operating pressure), the water type is 100 to 200 inches of water, and the flushing time is 5 to 200 inches.
30 minutes is preferable and necessary.

In the method of the present invention, it is preferable to add an anionic or nonionic interfacial T-occupant agent to the peroxidized water-containing liquid in order to improve the μ and lag effects.

When adding nitrate to the surfactant, it is preferable to adjust the degree of roughness to be about 0.05 to 0.3 weight. Specific examples of anionic surfactants include alkylpensene sulfones, higher alcohol acetic acid esters, alkylsulfosulfone esters, alkylnulphone IL alkylsulfosuccinates, dialkylsulfosuccinates, alkylnaphthalenesulfones-formalin condensation vlJ, Examples of nonionic surfactants include sulfone, polyoxyethylene alkyl ether, polyoxyethylene alkylaryl ether, polyenalene glycol fatty ester,
Polyoxyethylene J1 fatty acid amide ether, polyhydric alcohol fatty acid ester, alkylol amide, etc. are in contention.

In the present invention, according to the present invention, alkali, oxidizing agent, and reducing agent are added to hydrogen chloride, depending on the contamination.

Dispersants, #base, and other dispersing agents Y: You can also use them.

According to the present invention, hydrogen peroxide is first brought into contact with the hydrogen membrane to make it easy to peel off the contaminants. Does it decompose into bubbles? By controlling the generated camerase and controlling it with the amount of bubbles IP,
Contaminated W can be thoroughly peeled off and removed by the turbulent flow of air bubbles.

[Embodiments of the Invention] Hereinafter, the present invention will be explained in more detail with reference to the following examples, but the invention is not limited to the embodiments in 1: unless the purpose of the war is reflected. .

Example 1 Activated carbon treatment, mixed bed treatment, and UV sterilization for city water!
Ju l, Tasumi, H Touki Kogyo Co., Ltd. Spiral type ultrafiltration 1 odor content lI! I device, pressure 3-5 instant/d.

Water flow treatment was carried out for 6 months with water jt 1.5 m'/br. This 1FjJ, I used this water-based bath liquid once every 1 time.

Using this Moibunjin Tetsuin, Taniya) notation IK Bocho Chii liquid,
Nogi next ill 欣detective (熾1) (pressure 1.0kl?/1
-111% water ks00J/hr, iMj l during circulation
5 minutes) → Stationary contact (contact time 2 hours) → Time'tLvIi
(Arashi 2) (same conditions as dNnl liquid circulation) → Clean by water flushing (flushing time 5 minutes), and the performance of the ultrap membrane after cleaning was evaluated by Kurashin UltraV hyperosmosis and (
k, # compared with the performance of ultrafiltration without contamination. The results are shown in Table 1.

The performance of the membrane is determined by the population pressure of 1.1 for each membrane separation device.
The test was conducted by determining the differential pressure of the hood after passing pure water for 30 minutes at kp/cd and 1800 J/hr of water.

Table 1 M: 0.54JMzL)z Common FII (PH7)H+
C: Catalase l- in 0.5 fy MzLh solution
v#Yh5≦added m interval (pit 7) From Table 1, it can be seen that in the uninvented method, the recovery of the differential pressure was very good, and α# young and young fruits were lost. Furthermore, it is clear that even if the seedlings are plucked with a catalase-containing Yama02 solution from the beginning, as in Comparative Method 2, the effect is not good.

[Dull light effect]

As detailed above, the method for settling the membrane N1 apparatus of the present invention is to use H2O2 to easily remove scales, climbs, etc. attached to the membrane.
(Jz '(!' f) H) It is designed to electrically peel off the adhering proboscis by generating air bubbles, so it can easily and reliably remove contaminants deposited and attached to the pattern. However, it is possible to remove the taste.

It is very effective to remove slime, etc., which is difficult to remove with conventional anti-cleaning methods alone. According to the method of the invention, it is possible to reliably recover from problems such as an increase in running pressure caused by a single contamination in a quantitative manner, which is extremely advantageous industrially.

Special Foxman Kurita Industries Co., Ltd.

Claims (4)

[Claims] (1) A method for cleaning a membrane separation device, comprising supplying a hydrogen peroxide-containing solution to the membrane separation device, and then supplying a catalase-containing solution. (2) The method according to claim 1, wherein the membrane separation device is equipped with a reverse osmosis membrane or an ultrafiltration membrane. (3) The method according to claim 1 or 2, wherein the hydrogen peroxide-containing liquid contains a surfactant. (4) The catalase-containing liquid is made by adding catalase to a hydrogen peroxide-containing liquid! ff The method according to any one of claims 1 to 3.