KR20150020016A - A composition for decreasing hardness of water and removing radioactive substances and heavy metals in water - Google Patents

Abstract

The present invention is characterized in that it comprises (i) a colloidal silica solution containing ilite, (ii) a sodium carbonate solution, (iii) a polychlorinated aluminum solution, and a mixed solution of a ferric chloride solution and a phosphoric acid solution. To a water treatment composition useful for removing heavy metals. In addition, the present invention relates to a method for preparing a white precipitate by adding separately or together a colloidal silica solution and a sodium carbonate solution having a high hardness constant of 300 or more at a ratio of 1: 1, A polychlorinated aluminum solution, a ferric chloride solution and a phosphoric acid solution at the same volume ratio as that of the primary charged components to adjust the pH of the water to 7 to 8.

Description

TECHNICAL FIELD [0001] The present invention relates to a composition for removing hardness and for removing radioactive substances and heavy metals. BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to a composition for treating harmful substances in drinking water together with hardness drop of drinking water. In detail, the present invention is characterized in that it comprises a colloidal silica solution containing ilite, a sodium carbonate solution, a polychlorinated aluminum solution, a ferric chloride solution and a phosphoric acid solution, whereby the hardness of the drinking water is lowered and the radioactive material mixed in the drinking water To a multifunctional water treatment composition capable of removing harmful substances of heavy metals.

In the water treatment field, water is divided into constant water, heavy water and sewage water depending on the degree of cleanliness, and constant water is water that can be used as drinking water or washing water. The raw water containing natural water as raw water contains various minerals such as magnesium, calcium and iron. Natural water containing a relatively large amount of calcium salt and magnesium salt is referred to as hard water, and natural water having a low content of water is called soft water. If hardness is below 200, it is called hard water. Hardness is a concentration of calcium and magnesium dissolved in water, and is an index of water quality converted into calcium carbonate content, which corresponds to the sum of magnesium ion and calcium ion content in water. Hardness 1 means that 1 mg of calcium carbonate is contained in 1000 ml of water.

If the hardness of the raw water is too high, the bitter taste is not suitable for the drinking water, and if the hardness is too low, not only the water taste is obtained but also the supply of the minerals useful for the human body is also blocked. The World Health Organization (WHO) recommended standards are below 500, and in Korea, it is below 300. In general, the water purification plant has large-scale water purification facilities to lower the hardness of the raw water, and a water purification agent capable of maintaining a suitable level of hardness as drinking water is needed.

In the past, the inventors have developed a composition comprising 44 to 54% by weight of a soluble silica powder, 2 to 3% by weight of sodium carbonate and 44 to 54% by weight of ilite as a hardness lowering agent (Korean Patent No. 10-918273 ). This patented composition has been developed for the purpose of lowering the water hardness of 300 or less to a hardness of 100 or less in a household water purifier having a relatively small capacity rather than a large-scale water purification facility. However, in many countries, more than 300 high-grade water is used as drinking water. Therefore, in view of the circumstances of such countries, the necessity of a hardness reducing agent capable of refining raw water of high hardness has been raised.

Furthermore, due to the deterioration of the global environment, radioactive materials and water pollution caused by heavy metals are in serious condition. The representative radioactive material contained in drinking water is cesium and iodine, which can cause various cancers, and especially harmful to reproductive women and children. According to WHO guidelines, the drinking water limit of these radioactive substances ( ¹²⁵ I, ¹²⁶ I, ¹³¹ I, ¹³⁴ Cs, ¹³⁷ Cs) is less than 200 becquerels per kilogram. In the case of heavy metals, arsenic is a representative, and arsenic is classified as a primary carcinogen. Drinking drinking water containing arsenic can be fatal. Drinking water standards for arsenic are 10 micrograms / liter for each country including WHO. Filters are usually used to remove radioactive materials and elevated metals from raw water. However, since the radioactive substances and heavy metals are concentrated and remain in the filter, the use of the filter can make the raw water more dangerous. In many countries, especially in the backward countries, the residents are exposed to the water pollution caused by radioactive materials and heavy metals, and they have been neglected in the national level. However, considering the serious human health hazards of radioactive materials and heavy metals, it is urgently necessary to develop new alternatives to remove such harmful substances in drinking water to provide safe drinking water.

The powder input method using the composition of Korean Patent No. 10-918273 developed by the present inventors has a problem in that an excessive amount of the lowering composition should be added to the raw water having a hardness of 300 or more and therefore the powder hardens in an area having high humidity in the atmosphere It may be difficult to manage it in a proper amount. In addition, as described above, the powder composition of Korean Patent No. 10-918273 has been developed for the purpose of treating a raw material having a hardness of 300 or less with a small amount, and there is a limit to mass processing of raw water having a hardness of 300 or more. In addition, the composition of Korean Patent No. 10-918273 has been developed without taking into account the contamination of raw water by radioactive substances and heavy metals, so that there may be restrictions on usability.

The object of the present invention is to start from the intention to improve the powder composition of Korean Patent No. 10-918273 and to treat raw water having a hardness of 300 or more and contamination of radioactive substances and heavy metals, And to provide a multifunctional water purification agent of the new concept that effectively removes the substance to ensure both the water taste and the safety.

In one aspect, the present invention provides a method for preparing a solution comprising: (i) a colloidal silica solution containing ilite, (ii) a sodium carbonate solution and (iii) a polychlorinated aluminum solution, a mixed solution of a ferric chloride solution and a phosphoric acid solution And a water treatment composition for removing radioactive substances and heavy metals.

In another aspect, the present invention relates to a method for preparing a solution containing a colloidal silica solution and a sodium carbonate solution, which contain a primary light at a high hardness constant, and a step of forming a precipitate of fine white particles, And a phosphoric acid solution are injected to lower the hardness and at the same time remove radioactive substances and heavy metals.

The composition of the present invention can be useful as a multifunctional water purification agent capable of lowering the hardness constant of 300 or more to 100 or less and simultaneously removing various radioactive substances and heavy metals. In addition, since the composition of the present invention is in the form of a solution, it is advantageous in that it can be applied to a large-scale water purification plant as well as a small-sized domestic water purifier because it is easy to manage without being restricted by the amount of usage.

The hardness of water is proportional to the content of calcium ions and magnesium ions, which are bivalent cations contained in water. The higher the hardness of the water, the bitter the taste, and the better the feeling of aesthetics when drunk. Calcium and magnesium ions in the water are mainly derived from sulfate (CaSO ₄ or MgSO ₄ ), hydrogencarbonate (CaHCO ₃ or MgHCO ₃ ) and hydrochloride (CaCl ₂ or MgCl ₂ ). Bicarbonate present in hard water can be boiled and sedimented and softened, so hard water containing a large amount of hydrogencarbonate is called temporary hard water. On the other hand, sulfuric acid present in hard water is not precipitated even when boiled, so hard water containing a large amount of sulfate is called permanent hard water, and permanent hard water can be softened by treating with ion exchange resin. However, when treated with an ion exchange resin, Ca and Mg ions are ion-exchanged with Na ions, and when filtered with a membrane filter, not only Ca and Mg ions but also minerals useful for human body are completely removed, It becomes unsuitable.

Korean Patent No. 10-484561 discloses a water treatment composition for removing deodorant and heavy metals formed by granulation of zeolite, yellow soil, ilite and titanium dioxide powders. However, such a composition is not suitable as a water treatment agent for lowering the hardness of raw water.

Until now, a multifunctional water treatment agent capable of removing radioactive substances and heavy metals while lowering hardness has never been developed.

In one aspect, the present invention provides a method for preparing a colloidal silica solution, comprising: (i) a colloidal silica solution containing iodite, (i) a sodium carbonate solution, and (iii) a polychlorinated aluminum solution, a mixed solution of a ferric chloride solution and a phosphoric acid solution And a water treatment composition for removing radioactive substances and heavy metals. Preferably, the composition of the present invention is a composition comprising (i) a colloidal silica solution containing iodite, (ii) a sodium carbonate solution, (iii) a polychlorinated aluminum solution, a mixed solution of a ferric chloride solution and a phosphoric acid solution at a ratio of 1: Capacity ratio. More preferably, the mixed solution of component (iii) is prepared by adding a solution of component (i) and (ii) a solution of polyaluminum chloride in a ratio such that the pH of the water formed after introduction of the solution into raw water is about 7 to 8, Mix ferric chloride solution and phosphoric acid solution properly.

In a preferred embodiment of the present invention, the present invention provides a method for preparing a colloidal silica solution, comprising: (i) a colloidal silica solution containing iodide; (ii) a sodium carbonate solution; and (iii) a polychlorinated aluminum solution, a ferric chloride solution and a phosphoric acid solution at a volume ratio of 1: And a water treatment composition for removing radioactive substances and heavy metals. In a further preferred embodiment, the present invention relates to a method for preparing a colloidal silica solution, comprising: (i) a colloidal silica solution containing ilite, (ii) a sodium carbonate solution, and (iii) a polychlorinated aluminum solution, a ferric chloride solution and a phosphoric acid solution, Wherein the mixed solution of component (iii) is prepared by adding a solution of poly (aluminum chloride) chloride, a solution of poly (aluminum chloride) chloride A ferric solution and a phosphoric acid solution are constituted, and a water treatment composition for removing hardness and removing radioactive substances and heavy metals is provided.

The colloidal silica solution, the sodium carbonate solution, the polychlorinated aluminum solution, the ferric chloride solution and the phosphoric acid solution, which contain the sunlight used in the present invention, are preliminarily set in appropriate amounts and then the respective solutions are separately added to the raw water in any order Two or more of these may be blended into the raw water. In one aspect, the present invention relates to a process for the preparation of a white precipitate, which comprises firstly introducing a solution of colloidal silica containing sodium iodide in raw water and sodium carbonate solution separately or together at a volume ratio of 1: 1, A polychlorinated aluminum solution, a ferric chloride solution and a phosphoric acid solution at the same volume ratio as the first charged components to adjust the pH of the water to 7 to 8. The method of the present invention may be useful for treating hardnesses of 300 or higher.

In the colloidal silica solution containing ilite used in the present invention, the colloidal silica solution is a solution in which the silica (SiO ₂ ) solute is a particle having a particle size of 1 to 100 nm, which is a solvent (water, ethyl alcohol, methyl alcohol, isopropyl alcohol, Ethylene glycol, methyl ethyl ketone, etc.), the colloidal silica has a large number of OH groups on the surface, and a siloxane bond (Si-O-Si) Film forming property and adsorption property and is widely applied to various fields. Processes and prototypes for the preparation of colloidal silica solutions (e.g., Eskemec Co., Ltd.) are well known to those skilled in the art and can be used in the present invention.

Ilrite used in the present invention is a clay particle-sized fine-particle mineral having a chemical composition of (K, H ₃ O) Al ₂ (Si, Al) ₄ O ₁₀ (H ₂ O, OH) ₂ . According to the color, white ilite is classified into white ilite and yellow ilite. White ilite has more silicon dioxide (SiO ₂ ), less Al ₂ O ₃ , Fe ₂ O ₃ and K ₂ O than yellow ilite, and Cu, Zn , And heavy metals such as Fe, Cd and Pb are adsorbed and removed. Any sunlight can be used as a powder or suspension in combination with the colloidal silica solution of the present invention.

The sodium carbonate solution used in the present invention serves to convert CaSO ₄ to CaHCO ₃ in the permanent hard water. The magnesium ion and calcium ion in water are mainly derived from sulfate, bicarbonate, and hydrochloride. Bicarbonate present in hard water can be boiled and sedimented and softened, so hard water containing a large amount of hydrogencarbonate is called temporary hard water. In the case of hard water, it reacts with silica to precipitate calcium silicate. On the other hand, sulfuric acid present in hard water is not precipitated even when it is boiled, so hard water containing a large amount of sulfate is called permanent hard water. When calcium ion is present in water in the form of CaHCO ₃ , reactivity with silica is very low and CaSO ₄ is converted into CaHCO ₃ It is necessary to react with post-silica. Any sodium carbonate solution that is commercially available in the present invention can be used.

The polychlorinated aluminum solution used in the present invention is generally an aqueous solution of a polymer (Al ₂ (OH) _n Cl _6-n ) prepared from aluminum and hydrochloric acid and is designated as a water treatment agent as a kind of coagulant. Cohesive force in turbid water is 3 ~ 4 times more effective than the same amount of aluminum sulphate. Floc formed is very fast and large in sedimentation rate (3 ~ 4.5m / min) It is widely used for the purification of water and the like, and for the treatment of wastewater in factories and the like.

In the ferric chloride (FeCl ₃ ) solution used in the present invention, yellow FeCl ₃ .6H ₂ O can be obtained by heating the iron powder in chlorine or by oxidizing the iron chloride aqueous solution through chlorine. It is both delicate and strongly acidic. It is used as a coagulant for sewage and feces treatment and as a filter material for sludge dehydration because it coagulates the protein.

The composition according to the present invention has the effect of reducing the hardness of the drinking water and the harmful substances of radioactive substances and heavy metals mixed in the drinking water, the chemical reaction of which can be estimated as follows:

_{3SiO 2 · H 2 O + H} 2 O → SiO 4 -4 + H +

Ca ^{+ 2} + SiO ₂ ^-4 + H ₂ O → 3CaO · SiO ₂ (calcium silicate)

Mg ^{+ 2} + SiO ₂ ^-4 + H ₂ O? ₂ MgOSiO ₂ (magnesium silicate)

Ca ^{+ 2} + 3H ₃ PO ₄ + Cl → Ca ₃ PO ₄ Cl + H 2 (calcium chloride)

FeCl ₃ + OH -> Fe (OH) ₃ (iron hydroxide).

Synthetic zeolites such as calcium silicate, magnesium silicate and calcium chloride phosphate produced by the above chemical reaction have a function of adsorbing cesium, and iron hydroxide adsorbs and removes arsenic. Further, based on the above reaction formula, the composition of the present invention may have an effect of removing chlorine ions remaining in water. In general, elements of the same group in the periodic table of elements are similar in chemistry, so their reactivity is also similar. Under these conditions, heavy metals such as Al ⁺⁺⁺ , Fe ⁺ , Zn ⁺⁺ , and radioactive substances such as iodine, uranium, and radium can be adsorbed and removed. Since calcium silicate, magnesium silicate, potassium chloride phosphate and iron hydroxide are insoluble in water, they can be separated by precipitation, and sediments adsorbing the harmful substances can be discharged while being washed out of the water purification system.

Hereinafter, the present invention will be described in detail with reference to examples. These examples are presented for illustrative purposes only and are not to be construed as limiting the invention thereto.

Example  One

(A, B, and C), and the raw water was sealed to analyze the uranium and radon, the radioactive materials, at the Korea Basic Science Research Institute (http://www.kbsi.re.kr).

15 ml of a colloidal silica solution (containing 1 g of a 2.7% silica solution and 70 g of dilite) and 15 ml of a sodium carbonate solution (110 g / l) were added to 6 L of raw water, and after 20 minutes As precipitates of white fine particles formed, they began to precipitate on the bottom of the vessel. The pH at this time was 9.8. Subsequently, 15 ml of a mixed solution of polyaluminum chloride solution, ferric chloride solution and 7% phosphoric acid solution was added to the raw water to maintain the pH at about 7.5. After 3 hours, the precipitate was separated by settling and the supernatant was filtered. As a result of the analysis of the precipitates of the white fine particles, it was confirmed that calcium silicate, magnesium silicate, calcium chloride and iron hydroxide were mixed. In addition, changes in the hardness of the supernatant and levels of harmful substances were measured by the Korea Basic Science Institute. As shown in Table 1 below, the hardness reduction rate of treated water and the removal efficiency of uranium and radon of radioactive materials were considerably high.

Village in Chuseo District  Uranium (ug / L) Radon (pCi / L) Remarks
enemy
A 126.87 7600 US Acceptance Criteria:
Uranium 30 μg / L
4,000 pCi / L of radon)


Match B 73.98 7600 Competition C 97.36 6700
Treated water
A 0.00 <5 Match B 0.69 <5 Competition C 0.04 <5

Example  2

Since cesium and iodine generated during atomic nucleus cleavage do not occur without nuclear explosion, we made artificial wastewater with cesium and iodine.

15 ml of a colloidal silica solution (containing 1 g of a 2.7% silica solution and 70 g of dilite) and 15 ml of a sodium carbonate solution (110 g / l) were added to 6 liters of artificial wastewater for 20 minutes After the precipitation of white fine particles was formed, sedimentation started to occur on the bottom of the vessel. The pH at this time was 9.7. Subsequently, 15 ml of a mixed solution of polychlorinated aluminum solution, ferric chloride solution and 7% phosphoric acid solution was added to the wastewater to maintain the pH at about 7.5. After 3 hours, the precipitate was separated by settling and the supernatant was filtered. As a result of the analysis of the precipitates of the white fine particles, it was confirmed that calcium silicate, magnesium silicate, calcium chloride and iron hydroxide were mixed. In addition, changes in the hardness of the supernatant and levels of harmful substances were measured by the Korea Basic Science Institute. As shown in Table 2 below, the hardness reduction rate of treated water and the removal rate of radioactive cesium and iodine were significantly high.

Cesium (ppb) Iodine (ppb) Artificial wastewater 1112 32069 Treated water <1 7.194

Example  3

After collecting the water supply of the villages (D, E and F) in North district of Yeongwol-gun, Kangwon province, heavy metals such as copper, zinc and arsenic were artificially introduced into artificial polluted water in the Daeil environment (25-12 Dodang-dong, Wonmi- The analysis was commissioned.

Artificial contamination 15 ml of colloidal silica solution containing ILlite (1 L of a 2.7% silica solution and 70 g of ILLITE) and 15 mL of sodium carbonate solution (110 g / L) were added to 6 liters of water, After the precipitation of white fine particles was formed, sedimentation started to occur on the bottom of the vessel. The pH at this time was 9.7. Subsequently, 15 ml of a mixed solution of polychlorinated aluminum solution, ferric chloride solution and 7% phosphoric acid solution was added to the artificially contaminated water to maintain the pH at about 7.5. After 3 hours, the precipitate was separated by settling and the supernatant was filtered. As a result of the analysis of the precipitates of the white fine particles, it was confirmed that calcium silicate, magnesium silicate, calcium chloride and iron hydroxide were mixed. In addition, changes in the hardness of the supernatant and levels of harmful substances were measured by the Korea Basic Science Institute. As shown in Table 3 below, the hardness reduction rate of the treated water and the removal rate of harmful substances were considerably high.

Village in Chuseo District Copper (mg / L) Zinc (mg / L) Arsenic (mg / L) Remarks
Number of artificially polluted water
Yeongwol A 0.805 0.763 0.841 Tolerance criteria:
Copper 1 mg / L
Zinc 3 mg / L
Arsenic 0.1 mg / L

Yeongwol B 1.251 1.559 1.920 Yeongwol C 1.216 1.111 1.653
Treated water
Yeongwol A Non-detection Non-detection Non-detection Yeongwol B Non-detection Non-detection Non-detection Yeongwol C Non-detection Non-detection Non-detection

Example 4

After taking water from the village (F) of North village of Youngwol - gun, Gangwon - do, calcium and magnesium were artificially introduced into the raw water and adjusted to a high degree. The hardness reduction performance test was carried out on the hardwoods and the composition was as follows.

Unique hardness of raw water: 172.1

Hardwood adjustment Hardness: 313.9

Calcium concentration: 82.6 ppm

Magnesium concentration: 26.2 ppm

Sulfate ion concentration: not detected

15 ml of a colloidal silica solution (1.7 L of a 2.7% silica solution and a mixture of 70 g of Il light) and 15 ml of a sodium carbonate solution (110 g / L) were added to 6 L of a high-hardness raw water, After the precipitation of white fine particles was formed, sedimentation started to occur on the bottom of the vessel. The pH at this time was 9.7. Subsequently, 15 ml of a mixed solution of polychlorinated aluminum solution, ferric chloride solution and 7% phosphoric acid solution was added to the artificially contaminated water to maintain the pH at about 7.5. After 3 hours, the precipitate was separated by settling and the supernatant was filtered. As a result of the analysis of the precipitates of the white fine particles, it was confirmed that calcium silicate, magnesium silicate, calcium chloride and iron hydroxide were mixed. The change in hardness of the treated water was measured, and the results are shown in Table 4 below.

division The composition of the present invention Heat treatment Raw water hardness before treatment 313.9 313.9 Residual hardness after treatment 91.2 241.5 Reduced hardness 222.7 72.4 Hardness reduction rate (%) 70.9 23

The above description is merely illustrative of the technical idea of the present patent. Those skilled in the art will appreciate that various modifications and changes may be made without departing from the essential characteristics of the present invention. In addition, the embodiments disclosed in this patent are intended to illustrate rather than limit the technical idea of the present patent, and the scope of the technical idea of the present patent is not limited by these embodiments. Therefore, the scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be interpreted as being included in the scope of the present patent.

Claims (5)

(i) a colloidal silica solution containing iodide, (ii) a sodium carbonate solution, and (iii) a polychlorinated aluminum solution, and a mixed solution of a ferric chloride solution and a phosphoric acid solution. Composition. The method according to claim 1,
(i) a colloidal silica solution containing iodide, (ii) a sodium carbonate solution, (iii) a polychlorinated aluminum solution, and a mixture of a ferric chloride solution and a phosphoric acid solution in a volume ratio of 1: 1: 1. 3. The method according to claim 1 or 2,
The polychlorinated aluminum solution, the ferric chloride solution and the phosphoric acid solution are mixed in such a ratio that the pH of the raw water can be adjusted to 7 to 8. First, a solution of colloidal silica containing iodide in raw water and a sodium carbonate solution are separately or together introduced at a ratio of 1: 1, and a precipitate of white fine particles is formed, and then a solution of polychlorinated aluminum solution, And a phosphoric acid solution is added at the same volume ratio as the components charged at the first time to adjust the pH of the water to 7 to 8. The method of claim 3,
Wherein the hardness of the raw water is 300 or more.