WO2004045740A1 - Purification agent for wastewater and sludge water - Google Patents

Abstract

A purification agent for wastewater and sludge water, capable of even when the concentration of floating suspended substances in wastewater and sludge water is relatively high, accomplishing satisfactory flocculation (deposition)/separation of floating suspended substances, heavy metals, etc. without being influenced by the pH value of wastewater and sludge water. In the use of the purification agent, pH adjustment is not needed at the release of separated water, and the water content of flocculation deposit is low. The solubility of flocculation deposit in water is extremely low, and especially, flocculated heavy metals are substantially not re-dissolved in water. The purification agent for wastewater and sludge water comprises an organic acid, a crystalline aluminosilicate, an aluminum salt, a magnesium salt, a calcium salt and a sodium salt.

Description

 Description Wastewater and sludge purification agent Technical field

 The present invention relates to a purification agent for wastewater and sludge water. In particular, the present invention aggregates and separates suspended suspended substances contained in plating wastewater, various factory wastewater, wastewater from various construction sites, and dredged sludge water in sewage, sea, lakes, swamps, rivers, etc. And purification treatment agents for adsorbing and fixing and separating dissolved pollutants.

Background art

Various inorganic and organic coagulants have been used as purification agents for polluted wastewater. Examples of the inorganic coagulant, aluminum sulfate, polychlorinated aluminum two © beam (PAC), sodium aluminate (N a A 1 0 ₂₎ aluminum compounds such as iron sulfate _{(F e S 0 4 · 7} Η 2 θ ), iron compounds or quicklime such as iron chloride _{(F e C 1 3 · 6} H 2 0), such as slaked lime is used. As the organic coagulant, polyacrylamide, sodium alginate and the like are used. The conventional inorganic and organic flocculants as described above are primarily intended for the flocculation and separation of suspended solids (SS) in wastewater, but they are only capable of removing 50, OOOppm of SS. However, it cannot be said that it has a sufficient coagulation effect. In addition, the conventional coagulant has a pH dependence, and the appropriate pH varies depending on the treatment agent, and the pH may need to be adjusted during treatment. For example, when a divalent or trivalent iron salt is used as a flocculant, the optimum pH is about 6 to 8. In addition, polyacrylamides have a cloud point depending on pH and a temperature also has a cloud point (60.C). In the case of aluminum sulfate, aluminum hydroxide is necessary to effectively act as a flocculant, and DH4-5 generates aluminum hydroxide hydroxide ions. In addition, if the added amount is too large, the surface charges of the negatively charged SS colloid particles in the wastewater are reversed and dispersed. In other words, the coagulation effect of aluminum sulfate adsorbs negatively charged colloidal particles and neutralizes it with a positive charge.However, excessive adsorption causes the SS colloidal particles to become positively charged and repel and disperse. The coagulation effect cannot be exhibited. Furthermore, in the case of a conventional inorganic coagulant, it may be necessary to adjust the pH when separating water is discharged after coagulating SS in wastewater. For example, aluminum sulfate lowers the pH of water because it consumes the alkalinity of water. Among the inorganic coagulants, polyaluminum chloride (PAC) is an excellent one that does not significantly change the pH of water, and is used after being dissolved in water. However, since SS is adsorbed and cross-linked, the water content of the sludge that has been separated and coagulated is high, and it is necessary to further drain the dewatered sludge after treatment.

 Furthermore, as described above, SS is coagulated and separated with a conventional inorganic or organic coagulant, dehydrated, and the solidified sludge is easily dissolved in water. There were many problems such as elution.

 Therefore, it is selected from the group consisting of organic coagulants such as alumina, silicate, calcium sulfate, acrylamide coagulant and alginic acid coagulant, aluminum sulfate, aluminum chloride, and sodium carbonate, calcium carbonate, magnesium carbonate and dolomite. A purifying treatment agent for polluted wastewater containing at least one substance has been proposed (for example, Japanese Patent No. 2774096). However, even with such a purification agent, heavy metals, particularly chromium and zinc, could not be sufficiently removed. Disclosure of the invention

 (Technical problems to be solved by the invention)

 The present invention can sufficiently coagulate suspended suspended solids and heavy metals, especially chromium and zinc, regardless of the pH of the wastewater or sludge water, even if the suspended suspended solids in the wastewater or sludge water are relatively high in concentration. (Sedimentation) · Separation is possible, when the separated water is discharged: pH adjustment is not required, the water content of the coagulated sediment is low, the coagulated sediment hardly dissolves in water, and especially the coagulated heavy metal is almost It is an object of the present invention to provide a chemical for treating wastewater and sludge which does not re-eluted.

 (How to solve it)

 The present invention relates to a purification agent for wastewater and sludge water, comprising an organic acid, a crystalline aluminokerate, an aluminum salt, a magnesium salt, a calcium salt, and a sodium salt.

 (Effective effect than conventional technology)

The agent for purifying wastewater and sludge water of the present invention is capable of removing suspended suspended substances in wastewater and sludge water. Even at relatively high concentrations, it is possible to sufficiently coagulate (sediment) 'separate suspended solids and heavy metals, regardless of the pH of wastewater or sludge water.

 Further, when the purification treatment agent of the present invention is used, the: H adjustment is not required when the separated water is discharged.

 When the purification treatment agent of the present invention is used, the coagulated sediment has a low water content and is hardly soluble in water. In particular, the coagulated heavy metal hardly elutes again. BEST MODE FOR CARRYING OUT THE INVENTION

 The purification agent for wastewater and sludge water of the present invention comprises, as constituents, an organic acid, a crystalline aminosilicate, an anolemminium salt, a magnesium salt, a canoresium salt, and a sodium salt. In the present invention, the above object can be achieved for the first time by including these components in combination. If any of the above components are not included, the pH of the resulting purification agent will increase; if the suspended solids in the wastewater or sludge are relatively high, the suspended solids (Sedimentation) 'Can not be separated; requires pH adjustment at the time of discharge of separated water; high water content of aggregated sediment; aggregated sediment is easily dissolved in water Problems such as re-elution of aggregated heavy metals; In particular, if organic acids are not contained, heavy metals, especially copper and zinc, cannot be sufficiently removed.

 In the present specification, heavy metals that can be separated and removed by the purification treatment agent of the present invention are chromium, iron, manganese, aluminum, particularly chromium, and $ 0.

The organic acid used in the present invention is a low molecular weight organic compound which dissolves in water and exhibits an acidity. Considering that the separated water after the purification treatment is discharged into the natural world, the organic acid has a low molecular weight which exists naturally. Preference is given to using natural organic acids. The molecular weight of the organic acid is 1000 or less, preferably 10 to 1000, more preferably 50 to 300, and particularly preferably 100 to 200. Such preferred natural organic acids include, for example, malic acid, acetic acid, oxalic acid, tartaric acid, benzoic acid and the like. Among the above-mentioned natural organic acids, a natural organic acid having two or more, especially two, hydroxyl groups in the molecule and one or more, particularly one hydroxyl group is more preferably used. Such more preferred natural organic acids include malic acid, tartaric acid and the like, most preferably malic acid. The content of the organic acid is not particularly limited as long as the effects of the present invention can be obtained, and is usually 0.5 to 5% by weight, preferably 1 to 3% by weight based on the total amount of the purification agent. . Two or more kinds of organic acids may be used, and in such a case, their total content should be within the above range.

Crystalline Aruminokei salt has the general formula: having an _{x A l 2 0 3 y S} i 0 2 3 -dimensional network structure represented by, and is not particularly limited as much as possible capture heavy metals Ion in the air gap, the In the present invention, so-called zeolite is preferably used. Zeolite is a tectoaluminosilicate with a three-dimensional network structure. Specifically, the chemical structure of zeolite consists of a silicon tetrahedron formed by bonding silicon (S i) and four oxygens (O) existing around it, and by replacing the tetrahedral silicon. The main component is an aluminum-substituted aluminum tetrahedron (4-coordinated anorem), and these tetrahedra are connected to share four vertices. Voids of such a structure may contain weakly retained water that is easily dehydrated by heating or degassing, or may already contain alkali metal ions that are easily exchanged when capturing heavy metal ions. You may hold it. It is considered that the heavy metal ion trapping action of zeolite is caused by the generation of a permanent negative charge at the position of the four-coordinate aluminum based on the electrical balance between A1 and O. As long as the zeolite has the above-mentioned structure and action, the place of origin and production method are not particularly limited, and natural zeolite produced naturally, synthetic zeolite of high purity used as a catalyst, or artificial zeolites obtained from waste such as coal ash Any of zeolites may be used.

 The content of the crystalline aluminosilicate is 10 to 25% by weight, preferably 10 to 20% by weight, based on the total amount of the purification agent. Two or more zeolites may be used, and in such a case, their total content may be within the above range.

The aluminum salt is one or more compounds selected from the group consisting of aluminum sulfate, potassium aluminum sulfate, and aluminum chloride. Preferably, aluminum sulfate and potassium aluminum sulfate are used in combination. Potassium aluminum sulfate formula; is represented by _{KA 1 (S 0 4) 2} , Ru der what is referred Miyouban, Karimiyouban, and potassium Millau © van General. 20-40 weight ⁰ I relative to the content of the aluminum salt water treating agent total amount is preferably from 30 to 40 wt%. When two or more types of aluminum salts are used, their total content may be within the above range.

 The magnesium salt is, for example, magnesium carbonate. Preferably, the magnesium carbonate is supplied by dolomite. Since dolomite contains magnesium carbonate and calcium carbonate as main components, by using dolomite, magnesium carbonate and carbonated calcium carbonate as a calcium salt described later can be simultaneously supplied.

 The content of magnesium salt is 0.1 to 3% by weight, preferably 0.3 to 1.5% by weight, particularly 0.5 to 0.8% by weight based on the total amount of the purification agent. /. It is. When two or more magnesium salts are used, their total content may be within the above range.

 Calcium salt is one or more compounds selected from the group consisting of sulfated calcium and calcium carbonate. Preferably, calcium sulfate and calcium carbonate are used in combination. When calcium sulfate and calcium carbonate are used in combination, more preferably, calcium sulfate is supplied by warworms, and calcium carbonate is supplied together with magnesium carbonate by dolomite.

 The content of the calcium salt is 15 to 35% by weight, preferably 20 to 35% by weight based on the total amount of the purification agent.

~ 35% by weight. When two or more types of calcium salts are used, their total content may be within the above range.

 The sodium salt is, for example, sodium carbonate. A commercially available soda ash (dense; manufactured by Asahi Glass Co., Ltd.) is available as sodium carbonate.

 The content of sodium salt is 10 to 30% by weight, preferably 15 to 30% by weight based on the total amount of the purification agent.

~ 20% by weight. When two or more types of sodium salts are used, their total content may be within the above range.

The purification treatment agent of the present invention preferably further contains a polymer. Inclusion of polymer increases floc. As the polymer, a water-soluble polymer is used. In an aqueous solution, an anionic polymer having an anionic functional group, a cationic polymer having a cationic functional group, and a nonionic polymer having no ionic functional group are used. Can be classified. The anionic polymer is effective when the pH of wastewater and sludge water to be treated (hereinafter referred to as “wastewater”) is particularly 3 to 14, preferably 7 to 14. Specific examples thereof include, for example, polyacrylamide type. Commercial products of the polyacrylamide series include the Akofloc series (manufactured by Mitsui Cytec Co., Ltd.), the Senkafloc series (manufactured by Senniki Co., Ltd.), and the Aronsipolok series (manufactured by Toa Gosei Co., Ltd.) Available from Yo-Sumiflock series (Sumitomo Precision Chemical Co., Ltd.).

 Cationic 1-biopolymer is particularly effective when the pH of wastewater is 1 to 7. Specific examples thereof include poly (meth) acrylates, specially modified polyacrylamides, and polyamines. Commercially available poly (meth) athenoleate estenole-based, specially modified polyacrylamide-based, and polyamine-based products are available in the same series as the above-mentioned polyacrylamide-based commercial products.

 The nonionic polymer is particularly effective when the pH of the wastewater is 10 ~ 10. Specific examples thereof include, for example, polyatarylamide and the like. Polyacrylamide-based commercial products can be obtained from the same series as the above-mentioned polyacrylamide-based commercial products.

 The content of the polymer is not particularly limited, and usually 2 to 5% by weight of the total amount of the purification treatment agent is suitable.

 The purification treatment agent of the present invention can be prepared by mixing the above components with a mixer. For example, a predetermined amount of each of the above components together with a pigment ball (large, medium, and small beads) is put into a powder mixer such as a rocking mixer, a cement mixer, and the like, followed by stirring and mixing. Next, the upper, middle, and lower parts of the mixture were taken out in lkg each, and after uniformity of each component was confirmed by uniform dispersion of the color balls (beads), the pigment balls ( Beads).

For purification treatment of wastewater or the like, it is only necessary to put the purification treatment agent of the present invention into wastewater and turbulently agitate. This allows heavy metals to be adsorbed to the treating agent while flocculating suspended solids (pollutants) in the wastewater, resulting in precipitation and separation of the suspended suspended solids and heavy metals. In detail, within 1-2 minutes of starting stirring, polluted substances coagulate and precipitate, and most of heavy metals and other harmful substances are adsorbed by the treatment agent and the coagulation occurs. It is taken into things. When the stirring is stopped, the formed aggregates (coagulated sludge) immediately begin to settle and separate. The supernatant water and the coagulated sludge are completely separated, and the interface becomes clear. Heavy metals and other harmful substances are taken into the sedimented coagulated sludge, and are adsorbed and fixed on the surface. The sedimented and separated coagulated sludge has extremely high stability, does not collapse or dissolve even if it is stirred again, and rather tends to increase the sludge density. Also, there is no change with time, and the stability is high. In addition, the sedimented and separated coagulated sludge is mainly composed of oxides and is granulated, so that the sludge has an extremely excellent dewatering property.

The addition amount of the purification treatment agent of the present invention depends on the concentration of pollutants such as wastewater and the type and concentration of an organic substance such as an aqueous coating contained in the wastewater (particularly, the SS concentration). especially in the range of 50PPM~700PPM (700g from lm ³ per 50 g), it can achieve a cleansing process wastewater such interest.

 The purification treatment agent of the present invention as described above can be used in various pollutant wastewater treatment methods. Pollution wastewater treatment methods that can use the purification treatment agent of the present invention include, for example, physical treatment methods, physicochemical treatment methods, chemical treatment methods, and biological treatment methods. Examples of the physical treatment method include a screen method, a sedimentation method, a flotation method, and a filtration method. Examples of the physicochemical treatment method include various advanced treatment methods such as coagulation sedimentation method, pressure flotation method, activated carbon adsorption method, ion exchange method, reverse osmosis method, and electrodialysis method. Examples of the chemical treatment include a pH adjustment method, a neutralization method, an oxidation method, and a reduction method. Examples of the biological treatment method include an aerobic treatment method such as an activated sludge method, a biofilm method, and a ragged method, and an anaerobic treatment method. Further, the purification treatment agent of the present invention can be used also when treating by combining a plurality of these treatment methods. For example, coagulation sedimentation method for wastewater treatment with a lot of suspended solids, ion exchange method for suspended wastewater, anaerobic / aerobic activated sludge method for denitrification, ultrafiltration method for removing colloid particles, For removing aromatic compounds, it is particularly effective to apply the purification treatment agent of the present invention to an activated carbon adsorption method or the like. Furthermore, the purification treatment agent of the present invention can also be used for treating sludge generated in the treatment of wastewater as described above.

Specifically, the number of times of cleaning the screen can be reduced by using the treating agent of the present invention prior to the treatment by the screen method which is a physical treatment method. Also, the life of activated carbon Life is extended and replacements are reduced. In the case of wastewater treatment by the pH adjustment method, by treating with the treatment agent of the present invention, suspended substances can be removed, and the amount of the chemical used can be reduced by the action of anoremina amphoteric ions. In the case of the ion exchange method, the treating agent of the present invention acts as a natural inorganic ion exchange resin based on zeolite ion exchange ability and alumina amphoteric ion exchange ability. Further, in the neutralization method / oxidation method / reduction method, it is more effective if the treatment with the treating agent of the present invention is used in combination. Also, in the anaerobic / aerobic activated sludge method for the purpose of denitrification, if ammonia nitrogen is converted into ashiosan nitrogen, the treating agent of the present invention can remove nitrogen together with precipitated sludge. Further, when the aromatic compound is removed, if the emulsion is formed, it is possible to remove the aromatic compound by the treating agent of the present invention.

 Examples of the wastewater to be treated by the purification agent for wastewater and sludge water according to the present invention as described above include, for example, coke production wastewater containing cyanide by-produced when coke is produced by carbonizing coal. Mesh factory wastewater containing cyanide compounds used in the electroplating process, etc., fishnet factory wastewater containing tributyltin used as an antifouling agent for fishnets, and methylmercury used as catalyst mercury Various wastewaters containing heavy metals and other harmful substances, such as organic synthesis factory wastewater, semiconductor factory wastewater using chlorine compounds such as tetrachlorethylene and trichlorethylene as cleaning agents, and wastewater from cleaning plants. The purifying agent of the present invention may also be used for the treatment of wastewater from an organic leather manufacturing plant containing organic substances such as chromium used in the tanning agent, and organic or inorganic wastewater from a textile plant. Can be done. Furthermore, synthetic resins such as alkyd resins, acrylic resins, and polyester resins, surfactants, kents such as acetone and methyl ethyl kent, and polyhydric alcohols such as xylol, toluene, and propylene glycol discharged from coating plants. It can also be used for the treatment of wastewater containing tools, ester compounds, amyl compounds and the like.

 (Example)

 Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to Examples.

(Manufacture of purification agent A1) The following raw materials (300 kg) and beads made of butyl chloride resin (lmm in diameter) (500 ml) were charged into a mouth-mixer and mixed uniformly over 2 hours. The beads were removed from the mixture using a sieve to obtain a purification treatment agent A1.

 Raw materials for purification agent A1

 Dolomite (manufactured by PT. PRIMAPACKIMIA REJEKI) 4.5 parts by weight Zeolite (manufactured by PT. PRIMAPACKIMIA REJEKI) 18.7 parts by weight Aluminum sulfate 21.0 parts by weight Potassium aluminum sulfate 14.5 parts by weight Sulfuric acid calcium 16.7 parts by weight Part sodium carbonate 18.8 parts by weight malic acid 1.0 part by weight Polymer (Acofloc A95, manufactured by Mitsui Cytec Co., Ltd.) 2.0 parts by weight

 (Manufacture of purification agent A2)

 Except that malic acid was not used, the same procedure as in the method for producing the purification treatment agent A1 was carried out to obtain a dildo treatment ljA2.

 (Example 1)

500 ml of the coating wastewater containing the water-based paint was placed in a beaker, and 100 ppm of the purification agent A1 was added thereto, followed by turbulent stirring with a stirring rod for 1 minute. After that, the beaker was allowed to stand for 3 minutes, and the contaminants settled and separated, and the supernatant became clear. The supernatant was filtered through a 1 / zm mesh filter cloth (for analysis) to separate the settled sludge. Water quality was measured for the separated supernatant and raw water. The results are shown in the table below.

table 1

(Example 2)

 Except for using factory wastewater instead of coating wastewater, treatment of wastewater and water quality measurement of separated water were performed in the same manner as in Example 1. The results are shown in the table below.

 (Comparative Example 1)

 The treatment of wastewater and the measurement of the quality of separated water were performed in the same manner as in Example 1, except that factory wastewater was used instead of coating wastewater, and that purification treatment agent A2 was used. The results are shown in the table below.

 Table 2

(Example 3)

The treatment of wastewater and the measurement of the quality of separated water were performed in the same manner as in Example 1, except that factory wastewater containing dyes was used instead of the coating wastewater. The results are shown in the table below. Table 3

(Example 4)

 The treatment of wastewater and the measurement of the quality of separated water were performed in the same manner as in Example 1, except that the wastewater from civil engineering work was used instead of the coating wastewater. The results are shown in the table below.

 Table 4

(Example 5)

Except for using factory wastewater instead of coating wastewater, treatment of wastewater and water quality measurement of separated water were performed in the same manner as in Example 1. The results are shown in the table below. Two

Table 5

(Example 6)

Put industrial wastewater 500ml beaker, to which the purification treatment agent B1 was added 50 _PP m, and stirred for 1 minute turbulence with a stir bar. After that, the beaker was allowed to stand for 3 minutes. The contaminants settled out and the supernatant became clear. The supernatant was filtered through a mesh filter cloth (for analysis) to separate the settled sludge. Water quality was measured for the separated supernatant and raw water. The results are shown in the table below.

 Table 6

(Example 7)

500 ral of the water from the Uogiri Dam was put into a beaker, and the purification agent B1 was added with lOOppra, and the mixture was stirred turbulently for 1 minute with a stirring rod. After that, the beaker was allowed to stand for 3 minutes, and the contaminants settled and separated, and the supernatant became clear. The supernatant was filtered through a mesh filter cloth (for analysis) to separate the settled sludge. Water quality was measured for the separated supernatant and raw water. The results are shown in the table below. Table 7

(Example 8)

 When the coagulated sediment obtained in Example 1 was discarded, drainage treatment as a post-treatment was unnecessary.

 Further, the aggregated precipitate obtained in Example 1 was mixed with 500 ml of water, and the mixture was stirred for 1 minute and then collected by filtration. The weight of the collected sediment was almost the same as the weight before mixing with water.

 Further, the aggregated precipitate obtained in Example 2 was mixed with 500 ml of pure water, and the mixture was stirred for 1 minute and then filtered. Both the chromium and zinc contents in the filtrate were below the detection limit.

 (Measuring method)

The measurement method is shown in the following table. Table 8

Measurement item Measurement method

Transparency (mg / 1) JIS K0102-35. 1

Suspended solids (SS) ① (mg / 1) Sep. 30, 1974 Notice of the Environment Agency Notification No. 64 Appendix 8 Hydrogen ion concentration (pH) JIS K0102-12. 1

Suspended solids (SS) ② (mg / 1) December 28, 1971 B Announcement No. 59 of the Environment Agency Appendix 6 Biochemical oxygen demand (B0D) (mg / 1) End IS K0102-21.

Chemical oxygen demand (COD) (mg / 1) JIS K0102-17

Dumbbell or its compound (mg / 1) JIS K0102-53.3

Iron content (mg / 1) JIS K0102-57.

Chromium content (mg / 1) JIS K0102-65.1.4

Nickel and its compounds (mg / 1) JIS K0102-59.3

Claims

The scope of the claims 1. A purification agent for wastewater and sludge water containing organic acids, crystalline aluminokerates, aluminum salts, magnesium salts, calcium salts, and sodium salts. 2. The agent for purifying wastewater and sludge water according to claim 1, wherein the organic acid is a natural organic acid having a molecular weight of 1,000 or less.  3. The purification agent for wastewater and sludge water according to claim 1, wherein the organic acid is malic acid. 4. The treatment agent for purifying wastewater and sludge water according to claim 1, wherein the crystalline aluminosilicate is zeolite.  5. The wastewater and sludge according to claim 1, wherein the a / reminimum salt is one or more compounds selected from the group consisting of anorememidium sulfate, potassium anoremide sulfate, and aluminum chloride. Water purification agent.  6. The purification agent for wastewater and sludge water according to claim 1, wherein the magnesium salt is magnesium carbonate, and supplied by dolomite.  7. The treatment agent for purifying wastewater and sludge water according to claim 1, wherein the potassium salt is sulfuric acid and Z or carbonic acid.  8. The purification agent for wastewater and sludge water according to claim 1, wherein the sodium salt is sodium carbonate.