JPS61120686A - Treatment of dyeing waste water - Google Patents

Abstract

PURPOSE:To enable mass treatment, by neutralizing waste water to be treated to predetermined concn. before successively applying ultrafiltration and reverse osmosis membrane filtration thereto. CONSTITUTION:Waste water 10 to be treated is sent into a neutralization tank 25 by a pump 22 and neutralized. The neutralized waste water 11 is sent into ultrafiltration tanks 30, 31 to be stored therein and filtered by an ultrafiltration apparatus 40. Thus the primary treated water 12 obtained is subsequently stored in a reverse osmosis tank 50 and filtered to obtain secondary treated water 14 which is, in turn, once sent into a tank 70 to receive final check by a checking device 75 before being discharged or recirculated to be reused.

Description

[Detailed description of the invention] The present invention relates to a method for treating dyeing wastewater.

For example, in dyeing processes related to l&fiber content, large amounts of various dyes are used, and large amounts of expense and equipment are required to treat the wastewater.

Unlike general domestic wastewater, this type of dyeing wastewater is complicated to treat because it contains a wide variety of chemical components in large quantities, but it must also be treated under strict standards to prevent pollution. ,do not have.

In addition, in many conventional methods, the removed substances separated as a result of wastewater treatment contain chemicals, materials, liquids, etc. used for removal, so the amount of waste is several times that of the substances actually removed. Since waste products are produced, we now have to deal with the new problem of disposing of the large amounts of waste produced.

In view of this situation, the present invention has been developed to simply, easily, and reliably separate a large variety of chemical components mainly from dyeing wastewater, and furthermore, the amount of separated and removed substances is the same, and the post-processing is possible. The present invention also aims to provide a wastewater treatment method that greatly facilitates wastewater treatment.

The method for treating dyeing wastewater of this invention involves neutralizing the wastewater to be treated with an acid or base to a predetermined pH concentration, and then pumping it to an ultrafiltration device equipped with an ultrafiltration membrane for primary treatment. Water is obtained, and then the primary treated water is pumped to a reverse osmosis device equipped with a reverse osmosis membrane at a pressure higher than the osmotic pressure of the primary treated water to separate the secondary treated water. . Embodiments will be described below with reference to the accompanying drawings.

Figure 1 of the accompanying drawings is an overall flowchart of the treatment equipment showing an example of the method of the present invention, Figure 2 is a flowchart of the part shown together with a sectional view of an ultrafiltration device, and Figure 3 is a sectional view of a reverse osmosis device. It is a flowchart of the part shown.

The treatment method of the present invention will be explained according to the flow shown in FIG. 1. Reference numeral 10 represents the raw solution of wastewater to be treated;
0 is the raw water tank. Here, aeration treatment is performed as appropriate using a blower 21 or the like.

The wastewater 10 to be treated is sent to a neutralization tank 25 by a pump 22. This neutralization tank z5 has ♂
A PH control unit 26 is connected, and necessary acid components (
sulfuric acid) or a base component (sodium hydroxide) is appropriately added and mixed into the raw wastewater to meet the specified wastewater standards (PH6,8~
8). Reference numeral 27 is a filter for removing floating matter such as dust, and 28 is a stirrer.

The neutralized wastewater 11 that has been neutralized to a predetermined pH level is then sent to the ultrafiltration tank 30 (or 31) and stored. The reason why two (plural) ultrafiltration tanks are provided in the figure is that when the concentrate in one tank is to be disposed of or cleaned, the other tank can be used. Reference numeral 29 is a switching valve.

As is clear from the enlarged view of FIG. 2, the ultrafiltration device 40 is composed of a cylindrical body (so-called module) 41.41 in which an ultraviolet source and a membrane 42 are housed. ultrafiltration
Reference numeral 42 denotes a membrane-like filter medium made of cellulose acetate or the like and having a very uniform average pore size, through which fine particles can be separated and removed by forcing the waste water to pass through it.

The currently available ultrafiltration membranes are said to be capable of separating and removing solutions containing molecules or colloid particles with a molecular weight of approximately 1000 or more, although this varies depending on the molecular shape.

Regarding this ultrafiltration device 40, as shown in the cross-sectional view of FIG. When using a module, firstly, the flow of the liquid to be treated is parallel to the membrane, so there is less dirt adhesion, and secondly, even if dirt does adhere, the membrane surface can be easily scrubbed with a sponge pole, etc. Because you can.

In FIG. 2, reference numeral 43 indicates an inlet of the water to be treated, 44 an outlet thereof, and 45 an outlet of the primary treated water separated by the ultrafiltration membrane. In addition, in Figure 5, each tube type module 41
．． 41 are connected in series. Further, reference numeral 13 indicates a flow of concentrated wastewater separated and removed by the ultrafiltration device 4o, which is circulated and sent to the ultrafiltration tank 30 (31) again.

Symbols 32, 34, and 35 indicate switching valves, and 33 is a pressure pump of the ultrafiltration device, and the pressure in the example is about 10 kg/
cm'.

Primary treated water 1 obtained by the above ultrafiltration device 40
2 is then stored in the -H reverse osmosis tank 50 (or 51). The reason why two reverse osmosis tanks are provided is exactly the same as in the case of the ultrafiltration tank described above, and is due to the requirement for processing efficiency. Reference numeral 49 is a switching valve.

The primary treated water 12 in the reverse osmosis tank 50 is pumped into a reverse osmosis device 60 equipped with a reverse osmosis membrane at a pressure higher than the osmotic pressure of the primary treatment. As shown in FIG. 3, the reverse osmosis device 60 consists of a tubular body (module) 61 in which a pleated reverse osmosis membrane 62 is housed. The pleated membrane body 62 as in the embodiment has a large membrane area and is therefore suitable as a reverse osmosis membrane with a small amount of permeated water.

As is already well known, the reverse osmosis method uses a special semipermeable membrane such as cellulose acetate, and when a pressure higher than osmotic pressure is applied to the solution side, only water passes through the semipermeable membrane. This utilizes the reverse osmosis phenomenon in which water moves to the opposite side of the freshwater side. According to this reverse osmosis method, it is possible to separate ionic low molecules in angstrom units, which cannot be separated by the above-mentioned ultrafiltration method.

In FIG. 3, reference numeral 63 indicates an inlet of the primary treated water, and 64
65 is the outlet of the same outlet, and 65 is the outlet of the secondary treated water separated by the reverse osmosis membrane. Further, reference numeral 15 indicates the flow of the concentrated liquid of the primary treated water that has been separated and removed, and this is recirculated and sent to the reverse osmosis tank 50 (51) or the ultrafiltration tank 30 (31) as necessary. be done. Codes 52, 54.
Reference numeral 55 represents a switching valve, and reference numeral 53 represents a pressure pump of a reverse osmosis device, and the pressure in the example is approximately 30 kg/c considering osmotic pressure.
rn'.

The secondary treated water 14 treated as above is temporarily transferred to the tank 7.
0, and after undergoing a final check 75, it is discharged or used for circulation.

Next, various analytical data of the treated water at each stage in the above example will be shown.

To Raw wastewater Primary treated water Secondary treated water PH5, 75, 55, 8 BOD 1000 570 54CO
D 850 200
18-Hem extract 98 54 4T-N 13
1.8 3.8T-P 32.0
All units except 0.11 zero PH are p
p intestine.

The analysis method is that the PH is JIS-0101, 2, 1, B
OD is JIS-01Q1.21, COD is J
IS-0101,1? , N-Hex is Environmental Agency Notification Law 84.13, T-N is JIS-0101°45.144.2, T-P is JIS-0101
, 48, and 3, respectively.

According to this invention, as is clear from the analysis data at each treatment stage above, ultrafiltration and reverse osmosis treatment can provide extremely high treatment results across all wastewater standards, and it is difficult to achieve conventional treatment volumes. It was possible to carry out the dyeing wastewater treatment very effectively.

According to this method, as is clear from the above, the wastewater to be treated is separated into permeated liquid and concentrated liquid by the ultrafiltration membrane and reverse osmosis membrane, so the substances to be separated and removed are The substance itself contained within is not increased several times by removal agents, materials, liquids, etc. as in conventional methods. Therefore,
It is extremely convenient not only when disposing of the removed substance, but also when disposing of it by conventional methods such as activated sludge. In addition, as an example of the present invention, there is a method in which a step of mixing soil bacteria into the concentrated removed substance and decomposing it by the fungi is added.

As a final note, when implementing this method, as described in the example, when the ultrafiltration device is of a tube type and the reverse osmosis device is of a pleated type, it is necessary to A large contact area with the membrane is ensured, and there are advantages in terms of maintenance regarding the adhesion of dirt, etc., and it is suitable and practical for the treatment of large quantities of dyeing wastewater.

[Brief explanation of drawings]

Fig. 1 is an overall flowchart of the treatment equipment showing an example of the method of the present invention, Fig. 2 is a flowchart of this part along with a sectional view of an ultrafiltration device, and Fig. 3 is a flowchart of the ultrafiltration equipment along with a sectional view of the reverse osmosis device. FIG. 10...Wastewater to be treated, 11...Neutralized wastewater, 12...
・Primary treated water, 14...Second treated water, 40...
Ultrafiltration device, 60... reverse osmosis device.

Claims (1)

[Claims] 1. After neutralizing the wastewater to be treated with an acid or a base to a predetermined pH concentration, this is pumped to an ultrafiltration device equipped with an ultrafiltration membrane to obtain the primary treatment water. The dyeing wastewater is characterized in that the primary treated water is then pumped to a reverse osmosis device equipped with a reverse osmosis membrane at a pressure higher than the osmotic pressure of the primary treated water to separate the secondary treated water. processing method. 2. The method for treating dyeing wastewater according to claim 1, wherein the ultrafiltration device is of a tube type. 3. The method for treating dyeing wastewater according to claim 1, wherein the reverse osmosis device is of a pleated type.