JPH034985A - Extraction and aggregation of inclusion in water - Google Patents

Abstract

PURPOSE:To cause the union of dissolved ions and silica to take place and remove suspended substances due to adsorption on the silica by a method wherein the polymerization and gelation of the monomer silica contained in an aqueous solution is accelerated in the presence of Al<3+> or Fe<3+> ion. CONSTITUTION:The polymerization and gelation of monomer silica contained in an aqueous solution is accelerated in the presence of Al<3+> and/or Fe<3+> ion. During these processes, the dissolved ions are combined with the silica and suspended substances are adsorbed by the settling silica to extract and aggregate the inclusion in the water. As an alternative, the polymerization and gelation of the monomer silica contained in an aqueous acid solution is accelerated by adding OH<-> to make it weakly acidic and, during such processes, the dissolved ions or suspended substances are combined with or adsorbed by the silica to extract and aggregate the inclusion in the water.

Description

[Detailed Description of the Invention] [Industrial Application Fields] The present invention is applicable to the purification of various types of sewage, wastewater, closed system water, etc.
It relates to a method of separating and removing vA substances mixed in water, such as softening of hard water, and in particular utilizes the polymerization and gelation phenomenon of monomer silica dissolved in water to dissolve cations and some anions. The present invention relates to a novel method for extracting and aggregating pollutants in water, in which particles, organic and inorganic particles, bacteria, and other suspended solids (SS) are removed by binding or adsorbing them to silica and using particles that gel the silica.

[Prior Art] Wastewater discharged from various chemical factories, mining facilities, etc. contains a considerable amount of heavy metal ions and dissolved salts. Conventionally, these pollutants have been separated and removed by various methods such as pH adjustment using chemicals, precipitation, crystallization, ion exchange, aeration, and adsorption. Similar treatment may also be carried out at sewage treatment plants. In addition, hard water is softened by pumping sedimentation, boiling sedimentation, distillation, ion exchange, etc.

On the other hand, there is an urgent need to remove phosphorus contained in domestic wastewater, agricultural wastewater, fishpond wastewater, etc. as it causes eutrophication. The current situation is that Furthermore, in closed water systems such as wastewater and lakes, algae, bacteria, and other organic and inorganic particles are suspended in suspension. These are also sources of pollution, but like phosphorus, they are largely ignored.

[Problems to be Solved by the Invention] However, when adsorbents, flocculants, neutralizing agents, oxidizing agents, reducing agents, etc. are used in the conventional wastewater treatment technology described above, secondary pollutants may be mixed in and a large amount may be introduced. There are many orders for sludge, and the effort, cost, and drug costs required for processing these sludges are enormous.

In addition, extracting and coagulating ultrafine particles mixed in water is extremely difficult, and a large amount of flocculant or polymer flocculant and alkali treatment are added, but there are concerns about contamination due to the residual polymer flocculant.

Moreover, the electrolytic substance (mainly An◆3) conventionally used as a flocculant does not coagulate the dissolved ions at less than A/equivalent (usually about 1/2 to 1/3) L7, and is efficient. It's bad. Furthermore, in many conventional methods, chemicals, equipment, and processing operations are often different depending on the processing target. Other technologies also require huge equipment costs and running costs. In the case of water softening, distillation, ion exchange, and boiling are expensive, and long-term precipitation methods are low cost, but the process is unstable and takes time, and it is not possible to remove substances below the upper limit of solubility. There is.

In addition, in the case of treated domestic wastewater, combined treated water, and agricultural wastewater outside of cities, most of the phosphorus is discharged directly into rivers and lakes because the concentration of phosphorus is low and there are no effective treatment methods. . However, the amount of agricultural wastewater in particular is enormous, and the total amount of phosphorus is enormous. Organic and inorganic fine particles contained in these wastewaters and closed water systems are also largely left unattended. Even at urban wastewater treatment plants, phosphorus cannot be removed through biological treatment and sedimentation, and most of it is discharged as is due to cost considerations.

[Means for Solving the Problems] Therefore, as a result of intensive research in order to improve these drawbacks, the present inventors found that in the process of polymerizing and gelling fused silica by ionic reaction in an aqueous solution, dissolved ions and suspended silica The present invention was completed by focusing on the phenomenon of binding or adsorption of substances and silica.

In addition, the present invention is useful for extracting and coagulating contaminants in water, such as purifying sewage water and softening hard water, by binding or adsorbing these dissolved ions and suspended substances and gelling them. The gist is to promote the reaction by the coexistence of valent metal ions or by adjusting the pH. The gist of this method is to forcibly elute soluble silica, soluble alumina, or soluble iron from materials containing them, and to extract and coagulate contaminants in water using the eluted silicate power.

It is generally believed that when silica (Si02) is dissolved in water, it is bonded with OH- (SiOH), and especially when the dissolved silica exceeds 1100 pp, Si (OH) is formed.
It is said that the production of 4 is promoted (The Che
mistry of 5ilicon: Ra1pf
K, IIer).

These dissolved silicas exist in water in the form of hydrosils, and are known to exhibit special behavior and ionic reactions that differ from other ions. In other words, 5i(OH), s (monomer silica, monosilicic acid, silicic acid monomer) has the property of being extremely unstable and prone to condensation, and depending on the concentration, temperature, and PH, polymerization (condensation) occurs sequentially. Then, polymerization progresses to dimer and dimer, and polymer silica (
polysilica).

This reaction is an ionic reaction, and the reaction rate is p112-7
In the range of p(12
It is said that dehydration progresses in proportion to the hydrogen ion concentration. Further, a series of silicic acid reactions proceed rapidly in the slightly acidic region around p114-6, resulting in particle growth, and particle aggregation and gelation proceed rapidly in a simultaneous manner. When the concentration of monomer silica is high, the whole silica solidifies like agar, and when the concentration is relatively low, it precipitates into a colloidal state. However, it is said that depolymerization occurs on the alkaline side, particularly at pH 9 or higher, and that when the concentration is low, it reverts to monomer silica. It is also known that these polymerizations and gelations are promoted by the presence of other ions, especially polyvalent metal ions.

However, conventionally, there is no known method of purifying sewage using such properties of silica. Therefore, the present inventor conducted various experiments from the aspects of elution (melting) and polymerization/gelation of silica to examine whether such properties of silica could be utilized for the extraction and coagulation of contaminants in water. , very good results were obtained as described below.

First, an experiment was conducted to determine how fast the polymerization-gelation reaction actually takes place in water containing a high concentration of dissolved silica (Experiment 1). As a result, it was found that even in the pH range (pH 4 to 6) where the polymerization-gelation reaction is said to proceed rapidly, the reaction is extremely slow and cannot be put to practical use. This indicates that AI in dissolved silica-containing water! +3 or F
The same result was obtained even when metal ions other than 'e''''3 and phosphate ions coexisted (actual M3). However, when the fused silica aqueous solution was originally acidic (pH 2 to 6), the addition of OH- greatly promoted the polymerization-gelation reaction (Experiment 2).

Furthermore, if even a trace amount (several ppm) of AJ+3 or Fe+3 was allowed to coexist in water containing dissolved silica, the polymerization-gelation reaction proceeded rapidly, and at the same time, the concentration of dissolved ions and other contaminants was greatly reduced (experimental results). 3). This is due to the polymerization of silica dissolved in water as well as A1+3 and F.
This is thought to be due to the combination with e +3. In this case, 5i
OH and H+ are generated. That is, the following formula ■,
Due to (2), /l''3 and Fe+3 combine with silica to generate H''.

■(-3tOH)m +Al'= (-3iOH)m-n ・ (-51O)nA/÷3
+nH"■ (-5iOH)m +Fe"= (-5i OH) m-n ・(-5i 0)yIF
e' +n H"This reaction involves the addition of A to water containing dissolved silica.
A sudden increase in P due to addition of J+3 or Fe
This is also approved because it causes a decrease in H. In these reactions, when 1"3 or Fe+3 is added to the dissolved silica-containing water, 8/+3, Fe" not only becomes a hydroxide, but also forms a composite precipitate combined with silica. becomes. This fact indicates that silica bonds are also formed with other metal ions.

This released H+ moves the pH in a direction (around pH 4 to 6) that rapidly promotes polymerization and gelation of fused silica, thereby promoting gelation of silica. At that time, not only suspended substances contained in water but also metal cations and P-3
Extraction and aggregation are also performed on anions such as ions and alkaline earth metal ions such as Ca*2. In this case, if the pH drops too much, add OH- to make it slightly acidic (around pH 4-6).
It was also found that the reaction was further promoted by using (Experiment 3)
Alternatively, silica polymerization in the coexistence of Fe+3 - gelation promotion P
By controlling the H range, the expression of extraction and aggregation effects is enhanced.

2. Furthermore, the above 1. In addition, it promotes the monomer silica polymer silica gelation reaction by supplying OH to acidic water (pH 2 or higher) containing dissolved silica, and thereby enhances the extraction of dissolved ions and the aggregation effect of suspended substances in water. .

Therefore, the present invention can be said to be extremely effective as a method for extracting metal ions, some anions, alkaline earth metal ions, especially calcium ions, and aggregating suspended solids (SS). Moreover, it has excellent properties not found in the various flocculants and adsorbents that have been used in the past, and is highly valued as a future technology.

Next, based on the above experiments, an experiment regarding the elution of soluble silica was conducted. This method involves immersing materials that share soluble silica and soluble alumina (or soluble iron, or both) in waste water and physically forcing them to elute. An experiment was conducted in which the polymerization, particle growth, aggregation, and gelation reactions were caused to extract and coagulate pollutants in wastewater, and the effectiveness of this method was confirmed (Experiments 4 and 5).

Furthermore, a solution containing extremely high concentrations of soluble silica and soluble alumina was created by chemically forcibly dissolving soluble silica and soluble alumina using a material that shared them. Then, a small amount (ratio) of this solution is diffused into the wastewater to allow the silica polymerization-gelation reaction to proceed in a slightly acidic region (particularly preferably around p115 to 6), thereby extracting and extracting pollutants from the wastewater. An experiment was conducted to cause aggregation, and its effectiveness was confirmed (Experiment 6).

In addition, in the present invention, inclusions in water include Zn, Pb, A
Dissolved ions such as metal cations such as s, alkaline earth metal ions such as Ca +2, and some anions such as p-3,
Suspended substances such as organic and inorganic particles, bacteria, and algae (S
S).

In addition, extraction refers to combining dissolved ions with silica and polymerizing and gelling them together, and flocculation refers to adsorbing suspended substances in water to silica and polymerizing and gelling them integrally. , as a result of which these aqueous contaminants are separated from the water.

Physical means for forcibly eluting soluble silica and soluble alumina from materials that share them include mechanical impact (stirring, aeration, water flow, etc.), ultrasonic waves, magnetism, or a combination of these, and chemical means include hydrochloric acid, etc. , refers to elution with strong acids such as sulfuric acid.

In the present invention, the preferable pH range for promoting the polymerization-gelation reaction is 3.5 to 665, and the range in which the reaction occurs particularly rapidly is 4 to 6 in the case of addition of about /l, and more than that in the case of addition of Fe+3. It is somewhat low, about 3.5 to 6. If the reaction solution deviates from this range, it is preferable to adjust it by adding OH- or H+.

Furthermore, even if A 1 +3 and Fe+3 are present in extremely small amounts in the water containing fused silica, they promote the reaction to a certain extent.

0.5 to 0.5 depending on the concentration of dissolved silica in the water to be treated, the concentration of dissolved ions and impurities, the degree of removal of water inclusions, etc.
Even around 1 ppm is sufficient to achieve the purpose.

. On the other hand, silica (Si02) exists in inexhaustible quantities in rocks, and is also contained in large amounts in slag. However, the silica that can be used in the present invention is limited to soluble ones, ie, cristobalite and tridymite. Quartz is poorly soluble and cannot be used. This is because quartz has an extremely stable structure, whereas cristobalite and tridymite are in a metastable state.

Rocks containing a lot of cristobalite and tridymite (
Minerals include borosilicate (cristobalite), opalite, silica stone, etc. Zeolites also contain some cristobalite. These minerals whose main components are cristobalite, tridymite, and alumina silicate hydrate also contain soluble alumina, and can be used as they are in the present invention. These minerals are preferably used after being crushed in order to increase the contact area with water.

In addition, mining slag, especially water slag powder for fertilizer (blast furnace water slag), contains a considerable amount of silica (cristobalite type) and alumina (AI).
! 203) is included. Therefore, if this is treated with a strong acid, soluble silica and soluble alumina will be eluted at extremely high concentrations.

In the present invention, soluble silica refers to silica (Si02) that is contained in minerals and can be eluted in water, such as cristobalite and tridymite.
It refers to something combined with -.

However, the concentration of dissolved silica in the experimental results described later is
The value measured as i is shown in terms of 5i02.

[Action] Monomer silica (fused silica/dissolved silicic acid) and ions of Aβ13, Fe+3, or both are allowed to coexist in a water system in which sewage, wastewater, and other dissolved ions and suspended solids are to be separated and removed from the water to polymerize monomer silica. and promotes gelation, and during this process, dissolved ions and suspended solids are combined with or adsorbed on silica to extract and coagulate contaminants in water. When OH- is added to adjust the pH to an optimum level (about pH 4 to 6), the reaction is further promoted.

A material containing soluble silica and soluble alumina (or soluble iron, or both) is immersed in the water to be treated, and soluble silica and soluble alumina (or soluble iron, or both) are forcibly eluted using physical means, Polymerization and gelation of the eluted monomer silica is promoted, and during the process, dissolved ions and suspended substances are bound or adsorbed to the dissolved silica, thereby extracting and coagulating contaminants in water. Alternatively, extremely high concentration of fused silica-alumina (or iron, or both) can be obtained from the material using chemical means (strong acid treatment).
A solution is prepared, and this solution is added and dispersed in the water to be treated to promote polymerization and gelation of the added monomer silica, and during this process, dissolved ions and suspended substances are combined with or adsorbed to the silica to remove contaminants in the water. Perform extraction and aggregation.

[Experiment] Next, the method and results of the experiment on which the present invention is based will be explained in detail.

Experiment 1 In water containing a high concentration of dissolved silica (Sol, 1100 pp or more as SiO2), polymerization and gelation of silica progresses over time. In particular, this reaction proceeds rapidly at a high temperature of 80° C. or higher and under normal pressure.

In this experiment, the dissolved silica concentration (ppm) of two samples (A and B) was measured (atomic absorption spectrophotometry) immediately after pumping them up from underground (under high pressure), 24 hours later, and 30 days later. We investigated its behavior.

The measurement results are shown in Table-1. In addition, PH change is shown in figure 1 (fat), and fused silica (Sol, S i 0
2) The changes in each are shown below.

Table 1 As is clear from Experiment 1, the formation and gelation of monomer silica progresses over time even at room temperature. However, the reaction rate is extremely slow, and it is difficult to apply this reaction rate to water treatment.

It is said that dissolved silica moves in proportion to the amount of OH at pH 2 or above. Here, different types of geothermal water O
H- to Hc7! and NaOH to investigate the movement of the fused silica (measured by atomic absorption spectrophotometry).

As a result, as shown in Figure 2, the pH at the time of pumping was 6 or less (A
#1. pH 3,9), the amount of fused silica decreases (i.e. polymerization increases) as the pH increases (OH increases).
On the other hand, when the pH at the time of pumping is 7 or more (solution B p87.7), the amount of dissolved silica increases as the pH increases.

From this, in the case of acidic water with low pH, OH
By adding -, it is possible to extract and coagulate substances in water by utilizing the polymerization-gelation phenomenon of silica. However, if the original pH is high (7 or more), the amount of fused silica will not decrease even if OH- is added, and it cannot be used in the present invention.

(3-1) A large amount of silica is often dissolved in underground hot water. Therefore, various ions were added to pumped underground hot water, and the behavior of the dissolved ions was investigated as the fused silica polymerized and gelled. Incidentally, all measurements were performed according to the JIS-N method.

First, underground hot water (A) with a silica concentration of 830 ppm and underground hot water (B) with a silica concentration of 590 ppm were pumped up, and P (50 ppm), Zn (10 ppm),
Equivalent amounts of pb (10 ppm) and As (toρρIII) were added to prepare test samples (sample liquid A and sample liquid B).

In addition, Aj2''3 and Fe' were not detected (<
0.1 ppm). In addition, sample solution A contains 271 ppm of dissolved calcium and 35 ppm of SS component (polymerized S i 02 fine particles), and sample solution B contains 16 ppm of dissolved calcium and SS component (polymerized S i 02 fine particles) with a fine fM (< ippm) included. These values are shown in the column marked ■ in Table 2 and Figure 3.

The measured values (■) of this sample solution left standing for 24 hours (untreated) were almost the same as those of the above-mentioned (■).

On the other hand, an amount equivalent to A/'2 ppm was added to the obtained sample solution A, and an amount equivalent to Fe + 32 ppm was added to the sample solution B, and the mixture was stirred and left to stand for 60 minutes to form a precipitate and ripen/sediment.
The movement of dissolved ions and suspended solids was investigated. To my surprise, each sample solution was A7! After adding ``3'' or Fe*3, a significant PH decrease was observed along with the formation of a precipitate (measured value ■).

Next, 1N-NaOH was added dropwise to these solutions to make pl+
Adjust the temperature to around 6.5 to generate a precipitate, and after leaving it for 60 minutes,
We investigated the movement of ions in water. Precipitation progressed further (
Measured value ■). In addition, in ■, the precipitate -2+al (
1! Measured values for each item in Table 2 (bl (Fe) added), removal rate (ratio of average value of ■ to ■) are shown in ■.

The above experimental results are shown in Table 2(a) (in the case of A I!''3 addition), Table 2(b) (in the case of Fe+3 addition), and Figures 3 (al to (C)). Figure 3 (a) shows the change in the concentration of fused silica and ↑・P, fb) in the same figure shows the change in PH and the concentration of dissolved calcium and Zn, and (C) shows the change in the concentration of Pb and As.
and SS concentration changes are shown, respectively.

Note that dissolved calcium originally existed in underground hot water, and it is understood that this is reduced as the dissolved silica polymerizes and gels. The specificity of the present invention is clearly demonstrated by the fact that normally calcium is precipitated and removed only in the high pH range. In addition, SS in this experiment was polymerized S i
These are fine particles of O2, which were originally contained in the underground hot water, but increased after being left for 24 hours. This S
It can be seen that S was significantly reduced by the addition of A/+3.

As shown in the above data, extremely high extraction and flocculation effects were confirmed. Furthermore, addition of A I +3 and Fe showed a severe PH decrease. In addition, as Al”3, PAC
, polyiron was used as Fe12, but showed P11 reductions far exceeding the H+z provided by them.

Furthermore, a large amount of silica gel precipitate was generated, and cations and p-3 in the water were extracted and aggregated. Furthermore, it was confirmed that this reaction in the -layer was promoted by supplying OH-.

(4-1) Direct treatment experiment using borosilicate elution treatment (using physically forced elution).

Borosilicate of different grades was sized to about 8 to 20 mm grains and used for experiments.

Weighed 50g of borosilicate of different grades to produce 200mt.
Place it in a flat plastic beaker and add water to absorb enough water.
Wash thoroughly until no turbidity occurs when stirred. Add to this the test water (4 I of gray water! + 16 l of tap water + P-3
Add 100 ml of 10 ppm equivalent amount added) and place in an ultrasonic bath (
50 to 25 KHz), and elution was performed by applying ultrasonic vibration. The initial pH of this test water was 7.37, the dissolved silica concentration was 1°35 ppm, and the dissolved alumina concentration was <
0. lppm (not detected), T-PJ degree is l 1.7
5ppm, dissolved Ca is 22.2ppm, and bacteria (coliform group) as SS component is 27+000
n/ml.

The immersion water was sampled over time (30 minutes, 60 minutes, 120 minutes, and 180 minutes) from the start of vibration, and dried N
Measurements were performed on the filtered water obtained by filtering the precipitate with o2 filter paper, and the elution behavior, P removal, Ca removal, and SS removal behavior were investigated.

As a comparison, for each of the above borosilicate varieties (1, 4, 7, 8) that have a high elution of silica and alumina, the filtrated water of the immersion water that was immersed in the above test water for 16 hours and left to stand was compared. Similarly, the elution behavior, P removal, and Ca removal behavior were investigated. The measurement results are shown in Table 3 (a) and Figure 4 (a), respectively.
~ (shown in C1. Figure 4 (a) shows the concentration change of fused silica, the same figure (bl) shows the concentration change of fused alumina, and the same figure (C1 shows the concentration change of T-P. All measurements were carried out by JIS- According to the law.

From the experimental results, it was found that borosilicate table-3 was produced by ultrasonic elution.
(a) Low temporal elution) Soluble silica and soluble alumina are eluted from
It was observed that silica polymerization and gelation progressed over time. At the same time, coprecipitation of p-3 and SS components was also observed. It was also found that these effects were even greater for borosilicate, which has a large amount of eluted silica and alumina.

It was also confirmed that elution was greatly promoted by ultrasound.

(4-2) Among the borosilicate types mentioned above, for borosilicate (Nol, 4.7.8), which has a large amount of eluted silica and alumina, separately 50 g of each borosilicate was placed in 200 g of distilled water and subjected to ultrasonic elution for 60 minutes. The total dissolved amount (dissolved amount + precipitated amount) and residual dissolved amount (concentration in the filtrate filtered through 5B filter paper) were analyzed.

The measurement results are shown in Table 3(b) and FIGS. 4(a) to (C), which show that a large amount of the monomer silica eluted in this case becomes a precipitate. It was also found that Ca' eluted from borosilicate was also adsorbed to the silica precipitate and extracted and separated from water in large quantities.

Table 4 (b) (Reproducibility: 60 minute elution) (Adjustment of total elution amount (Reproducibility: 30 minute elution) (4-3) In order to investigate the elution behavior and dephosphorization behavior when ultrasonic elution is performed, the same test water used in Experiment 4-1 as No. 4.7 and 8 borosilicate was used. The treatment was continued and repeated until stability was observed in the dephosphorization behavior of each borosilicate.

The experimental results are shown in Tables 4(a) to (C1 and Figure 5 fat
- Not shown in (C). In this experiment, the experiment was repeated up to 6 times, but after the 4th time, the behavior stabilized (a change was observed).

In addition, in this experiment, 30 minutes (Table 4 (a), Figure 5 (a))
), 60 minutes (Table 4 (b), Figure 5 (b)) and 120 minutes
Investigations were conducted for each processing time shown in Table 4 (C) and Figure 5 (C)), and a similar stable trend around 1 was observed at all levels.

The test method was the same as above, and dissolved silica, dissolved alumina, dissolved calcium (only the third time of 60-minute elution and 120-minute elution), TP, and PH in the filtered water were measured. However, in the 30 minute elution, only T-P was measured.

The reason why the elution behavior and extraction/coagulation ability are stable in this way is that the mineral used is porous, the main component is cristobalite or tridymite, and the subcomponent is soluble alumina. Further, as the physical forced elution means, any method such as ultrasonic vibration, magnetic resonance, mechanical stirring, etc. can be used.

Experiment 5 About the white °~ (5-1)
Elution Experiment Using Magnetic Resonance 1 Put 400 g of borosilicate and 400 mL of distilled water into a β beaker, place it on a magnetic cooler with an intensity of 330 Gauss and 150 Gauss, and rotate the motor to average it horizontally. A magnetic field is applied, sampling is performed over time, and P
H was measured. In parallel, we conducted an empty experiment without applying a magnetic field, and confirmed that forced elution using magnetic field resonance was effective. (The borosilicate grain size used was 5 to 15 mm.) (5-2) Mechanical elution experiment A drum made of stainless wire mesh (90 mmφ x 250 m
mL), put 500 g of borosilicate (8 to 2 mm grains), immerse it in a semi-cylindrical water tank with a diameter of 100 mm, and
/min, and the effectiveness of forced mechanical elution was confirmed by measuring the pH over time.

The results of both experiments are shown in Table 5 and Figure 6. The reason why the movement of PH was used as an index in this experiment is as follows.

That is, borosilicate has S i O2 as a main component and Aj! as a subcomponent. It has 203. When these elutions occur, as mentioned earlier, (S iOH)m +Ae+3= (-3i OH) m-n ・(-3i O)r, A
I! H+ is generated by the reaction of ``+3+n H''. Therefore, the pH decreases in proportion to the extent of the elution reaction.

A highly concentrated fused silica-alumina solution was prepared by dissolving water slag powder for bamboo fertilizer (blast furnace water slag) in acid, and a small amount of this solution was mixed with gray water to confirm the extraction and flocculation effects.

Weigh out 2 g of water starch powder, transfer it to a 20 o ml poly beaker, and add H25O4 (1:9) 10011) to it.
Add chlorine and place in an ultrasonic bath to melt. In this case, there was some unmelted residue (quartz), but the supernatant liquid was used in the experiment. This supernatant liquid component has a pH of 1.3 and contains dissolved silica 6.
200 ppm, 2,550 ppm of molten alumina, and 7,300 ppm of molten calcium.

Take domestic wastewater 11 into a beaker, add 2 Il of the above supernatant liquid (melted silica-alumina liquid) (500 times dilution),
The mixture was stirred at 60 R/min for 60 minutes and allowed to stand for 60 minutes to ripen and settle the precipitate, thereby extracting and flocculating the pollutants in the water. Further, as a comparative example, a parallel test was carried out by adding PAC equivalent to 50 ppm (corresponding to 2 ml of supernatant liquid Ae2Q3). The experimental results are shown in Table 6 and Figure 7 fan (PH and T-
P) and Figure 7(b) (COD, T -N and N
Shown in H4).

As a result, compared to the addition of Al2O3 alone (PAC),
Addition of fused silica-alumina liquid was extremely effective.

This indicates that the silica behavior, which progresses through special ionic reactions of fused silica and heptanomer polymerization, aggregation, and gelation, is greatly involved in the extraction and aggregation of dissolved substances.

However, even if the fused silica-fused alumina aqueous solution is maintained at a pH of 2.0, which is considered to be the equilibrium point for the progress of polymerization due to H+ and OH- donation of fused silica, silica polymerization and gelation will proceed and solidify. . Further, when the pH was adjusted to 1.1, precipitation of anhydrous silica progressed.

Therefore, long-term storage of this solution was difficult.

[Effects of the Invention] As detailed above, the present invention promotes polymerization and gelation of dissolved silica by allowing AI+3 or Fe+3 or both to coexist in an aqueous system containing dissolved silica, and in the process, dissolves dissolved ions. This method separates suspended solids from water by combining them with silica and adsorbing suspended solids to silica precipitates. Further, the method involves polymerizing and gelling the fused silica using fused silica eluted from a material containing soluble silica, soluble alumina, etc. using physical or chemical means, and molten alumina or molten iron.

Therefore, 1. Since dissolved ions and suspended solids are gelled while being directly bound or adsorbed, there is no need for secondary, secondary, or tertiary treatment steps, which simplifies equipment and operation, and reduces equipment costs and management. Labor and costs are significantly reduced.

2. In particular, phosphorus, which was conventionally considered to be difficult to treat, is reliably removed.

3. The target water that can be treated is an extremely wide range, including wastewater from chemical factories and mining facilities containing heavy metal ions and dissolved salts, various types of wastewater such as domestic wastewater, agricultural wastewater, and fish pond wastewater, as well as hard water. It has a wide range of applications because it can be handled using similar methods.

4. The materials used are inexpensive and available in large quantities, such as minerals such as borosilicate and blast furnace slag, and the necessary components can be easily and reliably eluted by physical or chemical means.
Extremely low cost.

Additionally, large amounts of water such as agricultural wastewater can be easily treated.

5. Since there is no need for chemical treatment using adsorbents, flocculants, neutralizers, etc. or biological treatment, secondary pollutants will not be mixed into the water system. In addition, the amount of sludge generated is small;
The cost and effort required for these can be significantly reduced.

6. Compared to conventional PAC, alumina-based or iron-based flocculants, it causes a dephosphorization phenomenon that far exceeds the AI equivalent and Fe equivalent, and also removes trace amounts of metals that cannot be precipitated and separated by alkaline treatment. It is possible to remove ions and to precipitate and remove Ca+2, which is difficult to precipitate in a slightly acidic aqueous solution.

7. The gelled product can be easily separated from water by sedimentation, sand filtration, etc., and post-treatment is extremely simple. The gelled product does not become a source of secondary pollution, and in some cases can be used as a soil conditioner as is or even be buried in a landfill, eliminating the hassle and cost of post-treatment.

It is extremely meaningful and has many excellent advantages.

[Brief explanation of the drawing]

Figure 1 (a) is a graph showing the change in PH of geothermal water containing high concentration silica over time, Figure 1 (b) is a graph showing the change in dissolved silica concentration, and Figure 2 is a graph showing the change in PH of geothermal water containing high concentration of silica. Graph showing the relationship between the solubility of silica, Figure 3 (al is the change in the concentration of dissolved silica and T-P when A1°3 or Fe is added to underground hot water, and the fill in the figure is the same <PH and calcium The same figure (C1 is a graph showing the same < pb and the concentration change of As and SS, respectively. Figure 4 (a) is a graph of borosilicate immersed, left standing, and subjected to ultrasonic vibration. The concentration change of eluted fused silica (fb in the same figure) is the same as the concentration change of fused alumina, '(C1 is the same < T
Figure 5 is a graph showing the dephosphorization behavior of borosilicate immersion water in which the components were eluted by ultrasonic waves. Figure 5 is a graph showing the repeated treatment of the dephosphorization behavior of borosilicate soaked water in which the components were eluted with ultrasonic waves.
l is 60 minutes, Figure (C) shows repeated treatment for 120 minutes, Figure 6 is a graph showing the PH change of borosilicate soaked water with components eluted by magnetic resonance and mechanical impact, Figure 7 Ta
l is a graph showing the change in prr and dissolved silica concentration when a high concentration silica-alumina solution is diffused into the water to be treated; be. 1st (a) (b) Steaming 2 times 3 4 5 6 7 8 9 10 I+ 12n 523- 88 ε 0 α 2 6th series 7 times

Claims (1)

[Claims] 1. Al^+^3 and/or in an aqueous system containing monomer silica
Or an underwater solution characterized by allowing Fe^+^3 ions to coexist to promote polymerization and gelation of monomer silica, and during the process, dissolve ions are combined with the silica and suspended substances are adsorbed to the silica precipitate. Method for extracting and aggregating contaminants. 2. The method for extracting and coagulating contaminants in water according to claim 1, wherein OH^- is added to make it near-neutral and slightly acidic to further promote polymerization at the stage when the pH has decreased. 3. By adding OH^- to an acidic aqueous system containing monomer silica to make it slightly acidic, polymerization and gelation of monomer silica is promoted, and during this process, dissolved ions and suspended substances are combined with or adsorbed to the silica. A method for extracting and coagulating contaminants in water. 4. Forcibly eluting soluble silica, soluble alumina, and/or soluble iron from a material containing soluble silica, soluble alumina, and/or soluble iron in water using physical means, and polymerizing/gelling the eluted monomer silica. A method for extracting and coagulating contaminants in water, which is characterized by combining or adsorbing dissolved ions and suspended substances with silica during the process of proceeding with a chemical reaction. 5. From materials containing soluble silica, soluble alumina, and/or soluble iron, soluble silica, soluble alumina, and/or soluble iron are forcibly eluted by chemical means to obtain extremely high concentrations of soluble silica containing alumina and/or iron. A feature of this method is to create a solution, diffuse the solution into water relatively quickly, and perform a polymerization/gelation reaction of monomer silica under slightly acidic conditions, thereby binding or adsorbing dissolved ions and suspended substances in the water with the silica. A method for extracting and coagulating contaminants in water.