JPH0686986A - Method for treating waste liquid and device using the method - Google Patents

Abstract

(57) [Summary] [Object] To provide a waste liquid treatment method and apparatus for continuously clarifying an emulsion or latex-containing waste liquid. [Structure] The waste liquid treatment apparatus includes a mixing tank 8 for mixing the waste liquid and a CMS-based organism, and a static mixer 12, 13 which is an example of a stirrer for adding an inorganic coagulant or a polymer coagulant to the mixed liquid and stirring them. , 14, a settling tank 24 for sedimenting and separating the aggregates, and a dehydrator 3 for dehydrating the separated aggregates.
4 and.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to textile processing, paint, paper,
The present invention relates to a method and an apparatus for treating an emulsion- or latex-containing waste liquid discharged during the production or use of a polymer emulsion or latex that is consumed in large quantities with the development of the adhesive, synthetic fiber, rubber and other industries.

[0002]

2. Description of the Related Art Conventionally, as a device for separating a suspension in which a solid substance is dispersed in a liquid into a clear liquid and a concentrated slurry in a production process such as water and sewage treatment and the above-mentioned fiber processing. Various sedimentation separators are provided. On the other hand, in the case of a suspension in which an emulsion or latex is dispersed, the suspended particles are extremely fine, about 0.05 to 5 μm, and since the density of the particles is close to that of water, these particles are It was difficult to settle easily, and even if it settled, filtration of the sediment was extremely difficult. Therefore, in the case of an emulsion or latex-containing waste liquid, a batch-type sedimentation separation device is widely used in which a coagulant is added to apparently make coarse particles and the waste liquid is allowed to stand for a certain period of time and then discharged. It was

[0003]

However, in such a conventional separation apparatus, it is difficult to sufficiently clarify the waste liquid in a short time because the sedimentation speed of the agglomerated particles is slow.
Moreover, there is a problem that continuous treatment of waste liquid is impossible. The present invention has been made in view of such problems of the prior art, and an object of the present invention is to enable formation of flocs (aggregates) having a high aggregation rate and to continuously contain emulsion or latex. It is an object of the present invention to provide a method and an apparatus for treating a waste liquid that clarify the waste liquid.

[0004]

In order to solve the above-mentioned problems, the processing method of the present invention is a method for coagulating and separating particles having a resin as a main component from a waste liquid containing a polymer emulsion or a latex. (1) Ca-M
The gO-SiO ₂ system comprising a compound thermal decomposition products or mixtures of the product with an iron salt or a magnesium salt,
Adding to the waste liquid and mixing, (2) adding an inorganic coagulant or an inorganic coagulant and a polymer coagulant to the treatment liquid obtained in the step (1) and stirring the mixture, (3) (2) ) A step of sedimenting and separating the aggregate from the treatment liquid obtained in the step,
(4) The step of dehydrating the agglomerate, and the steps (1) to (4) are continuously performed.

Further, the processing apparatus of the present invention is a Ca-Mg-
A thermal decomposition product composed of a SiO ₂ compound or a mixture of this product and an iron salt or a magnesium salt, an inorganic coagulant or an inorganic coagulant and a polymer coagulant are added to a waste liquid containing a polymer emulsion or a latex. A treatment device for adding and mixing, and continuously aggregating and separating particles having a resin as a main component from this waste liquid, wherein Ca-Mg-SiO ₂
A thermal decomposition product consisting of a system compound or a mixture of this product and an iron salt or a magnesium salt is added to a waste liquid and mixed, and a treatment liquid discharged from the mixing tank is treated with an inorganic coagulant or A stirrer for adding and stirring an inorganic coagulant and a polymer coagulant, and a settling tank for settling and separating coagulates from the treatment liquid discharged from the stirrer,
A dehydrator for dehydrating the agglomerates, and the agitator is provided with an agitating member therein.

[0006]

In the present invention, when treating a waste liquid containing an emulsion or a latex, Ca-Mg is used.
A step of mixing the waste liquid with a thermal decomposition product composed of an O-SiO ₂ compound or a mixture of the product and an iron salt or a magnesium salt (hereinafter referred to as a CMS composition), an inorganic coagulant or an inorganic coagulant. The step of adding and stirring and the polymer flocculant and the step of performing sedimentation separation were divided into a mixing tank, a stirrer, and a sedimentation tank.

In this case, the waste liquid and CMS are mixed in the mixing tank.
It is considered that a good dispersion state with the system composition is obtained, and that the pH of the waste liquid is adjusted and the reaction between the CMS system composition and the flocculant is rapidly and sufficiently performed in the stirrer. It is considered that this reaction destroys the emulsified state of the resin, which is the main component of the emulsion or latex, and forms strong and large aggregates in which these resins and the like are adsorbed on the surface of the CMS composition.

Therefore, as compared with the case where these two steps are carried out in one tank, a more rapid and sufficient reaction can be obtained through a slightly macroscopic dispersion in the mixing tank.
On the other hand, the agglomerates obtained in the above two steps continuously settle in the settling tank, and a clarified treatment liquid (pH adjusted) is continuously obtained. Therefore, by organically connecting these three steps and treating them in a series of streams, continuous clarification treatment of the emulsion or latex-containing waste liquid becomes possible.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic sectional view showing an example of a waste liquid treatment apparatus of the present invention. In this figure, this waste liquid treatment apparatus comprises a mixing tank 8 for mixing the waste liquid and the CMS-based organism, and a static mixer 12 which is an example of a stirrer for adding an inorganic coagulant or a polymer coagulant to the mixed liquid and stirring the mixture. , 13,
14, a settling tank 24 for sedimenting and separating the aggregates, and a dehydrator 34 for dehydrating the separated aggregates.

The mixing tank 8 has a substantially cylindrical shape and a lower portion thereof has a tapered shape. At the top of this mixing tank 8 is a motor 3
Is provided, and stirring blades 6 and 7 are attached to a drive shaft 5 connected to the motor 3. In the mixing tank 8, the waste liquid supplied from the waste liquid supply pipe 4 and the CMS
The CMS composition supplied from the system composition storage tank 1 through the belt conveyor 2 is mixed by the stirring blades 6 and 7, whereby a good dispersion state is obtained. Note that C
The MS composition can be obtained by the method described in JP-A-63-305990 or JP-A-2-111407. That is, a natural dolomite ore and ground coal are mixed, the mixture is heated in an electric furnace, then ground in a test mill, and then passed through a predetermined standard sieve to obtain a CMS composition. Ferrous sulfate, magnesium sulfate, etc. may be added to the CMS composition as appropriate.

The mixed solution obtained in the mixing tank 8 is supplied to the pump 10 via the valve 9, and then is pumped by the pump 10 to the static mixers 12, 13 and 14 sequentially through the pipe 11. These static mixers 12, 1
Elements 15, 16 and 17, which are an example of a stirring member, are inserted into 3 and 14, respectively. An inorganic coagulant storage tank 18 and a polymer coagulant storage tank 21 are provided between the static mixers 12 and 13 and between the static mixers 13 and 14, respectively, via valves 19 or 22, respectively. By the pump 20 or 23, the static mixer 13
Or 14 an inorganic coagulant (for example, aluminum sulfate)
Or polymer flocculant (eg, anionic polyamide)
Can be introduced. As described above, in the static mixers 12, 13, and 14, the channel agitation is performed while the inorganic coagulant and the polymer coagulant are sequentially added to the mixed liquid introduced from the mixing tank 8 as needed, and The treated liquid thus obtained is transferred to the intake pipe 25 of the settling tank 24.

The sedimentation tank 24 is provided with an intake pipe 25 in the central part, a drain port 26 in the upper part, and a sludge discharge port 27 in the lower central part. The reaction of the static mixer treatment liquid introduced from the intake pipe 25 is sufficiently advanced, and strong and large agglomerates continuously and rapidly settle in the lower part of the settling tank 24. The sedimented agglomerates are transferred from the sludge discharge port 27 to the pump 29 via the valve 28, and then the pump 29 passes through the pipe 30 and the dehydrator 3
Transferred to 4.

The transferred aggregate is dehydrated by a dehydrator (for example, a centrifuge) 34. Due to the good dewaterability of the agglomerates, the water content of the separated sludge is low.
If necessary, a polymer coagulant storage tank 31 can be provided between the pump 29 and the dehydrator 34, and the polymer coagulant is added by the pump 33 via the valve 32, whereby the dehydration is performed. The separated liquid processed by the machine 34 may be clarified (cleared). On the other hand, the clarified treated water is discharged through the outlet 2.
It is continuously discharged from 6. The pH of this treated water is neutral.

The present invention has been described above with reference to the embodiments.
The present invention is not limited to this, and various modifications can be made within the scope of the present invention. For example, the shape, the mounting position, and the number of the stirring blades 6 can be changed as appropriate. Further, the size and the number of the static mixers 12 and the like to be installed can be appropriately changed. Further, the shape, number, and material of the elements 15 (eg, stainless steel, F
(RP, ceramic) can be changed as appropriate.

The amount of the treating agent added can be appropriately selected depending on the type, composition and concentration of the resin component of the waste liquid and the type and concentration of the emulsifier. Generally, the higher the concentration of the resin contained in the waste liquid, the larger the amount of the treatment agent added, but it is necessary to determine the amount of addition in consideration of the properties after clarification. Specifically, the blending amounts shown below are preferable. CMS-based composition: 0.1 to 1.0 times the weight of resin in the waste liquid Inorganic coagulant (sulfuric acid band): 0.1 to 1. 0 times polymer flocculant ・ ・ ・ ・ ・ ・ ・ ・ 1 × 10 ^-7 〜 1 ×
10 ^-6 times

[0016]

As described above, according to the present invention,
The waste liquid and the CMS composition are mixed in a mixing tank, and then an inorganic coagulant or an inorganic coagulant and a polymer coagulant are added by a stirrer and stirred, so that a strong and large aggregate is quickly and Settles continuously. Further, the pH of the clarified treated water in the sedimentation tank is neutral, and since the aggregates have a good dehydration property, they can be easily dehydrated by a dehydrator, and the water content of the separated sludge becomes extremely low. That is, it is possible to provide a method and an apparatus for treating a waste liquid, which continuously clarifies the emulsion- or latex-containing waste liquid.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an example of a waste liquid treatment apparatus of the present invention.

[Explanation of symbols]

 8 Mixing Tank 12 Static Mixer 13 Static Mixer 14 Static Mixer 18 Inorganic Flocculant Storage Tank 21 Polymer Flocculant Storage Tank 24 Sedimentation Tank 34 Centrifuge

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kazuhiro Segawa, 8-2 Goi Minamikaigan, Ichihara-shi, Chiba Calceed Co., Ltd. (72) Masayuki Takashima 6-12, Roppongi, Minato-ku, Tokyo High-pressure gas industry Within the corporation

Claims (2)

[Claims] 1. A method of coagulating and separating particles containing a resin as a main component from a waste liquid containing a polymer emulsion or a latex, wherein (1) Ca-MgO-SiO.
_The thermal decomposition product consisting of the ₂ type compound or a mixture of this product and an iron salt or a magnesium salt is added to the waste liquid and mixed, and the treatment liquid obtained in the steps (2) and (1) has an inorganic content. Adding the aggregating agent or the inorganic aggregating agent and the polymer aggregating agent and stirring, (3) a step of sedimenting and separating the agglomerates from the treatment liquid obtained in the step (2), and (4) the agglomerates And a step of dehydrating, wherein the steps (1) to (4) are continuously performed. 2. Polymerization of a thermal decomposition product composed of a Ca—Mg—SiO ₂ compound or a mixture of this product and an iron salt or a magnesium salt, an inorganic coagulant or an inorganic coagulant and a polymer coagulant. A treatment device for adding and mixing to a waste liquid containing a system emulsion or latex and continuously aggregating and separating particles having a resin as a main component from the waste liquid, which is a thermal decomposition product composed of a Ca-Mg-SiO ₂ compound. Alternatively, an inorganic coagulant or an inorganic coagulant and a polymer coagulant are added to a mixing tank for adding a mixture of this product and an iron salt or a magnesium salt to a waste liquid and mixing them, and a treatment liquid discharged from the mixing tank. And a stirrer for adding and stirring, a settling tank for settling and separating aggregates from the treatment liquid discharged from the stirrer, and a dehydrator for dehydrating the aggregates, Serial agitator processing apparatus liquid waste comprising the stirring member therein.