KR102002775B1 - Manufacturing method of ceramic ball for water treatment - Google Patents

Abstract

The present invention relates to a method for manufacturing a ceramic ball for water treatment. The method comprises the steps of: manufacturing slurry by mixing a composition formed of scoria, silica (SiO_2), calcium carbonate (CaCO_3), gold (Au), and silver (Ag) powder; injecting the slurry into a pressure vessel and performing hydrothermal treatment; manufacturing a dry ball by molding the hydrothermally treated slurry into a ball shape and drying the same; heat-treating the dry ball at a temperature of 800-1000°C. The present invention can provide a ceramic ball for water treatment which can maintain a filtration function and a long life even at high water pressure.

Description

TECHNICAL FIELD [0001] The present invention relates to a method of manufacturing a ceramic ball for water treatment,

The present invention relates to a method for producing a ceramic ball for water treatment, and more particularly, to a method for manufacturing a ceramic ball for water treatment capable of maintaining a filtering function and a long life at a high water pressure through a ceramic ball manufactured using a composition comprising scoria .

Ceramic balls manufactured by molding a ceramic material have a porous structure and are used for water purification and water treatment because they can remove harmful components, microorganisms, bacteria and the like remaining in the aqueous solution.

Korean Patent Registration No. 10-0377776 improves the sterilizing effect in the water treatment process through water-treatment ceramic balls prepared by mixing borax, copper sulfate and silver compounds. Also, in Korean Patent Registration No. 10-0716742, a water-treating ceramic ball prepared by mixing and molding tourmaline, chrynophtholite, mordenite, and granitoplyri is applied to water and functional water production. In addition, in Korean Patent Registration No. 10-1485861, the effect of enhancing the adsorption of heavy metals and improving the antimicrobial activity in water is achieved through the ceramic ball for water treatment prepared by mixing and molding serisite, elvanite, ilite, germanium, feldspar, have.

These ceramic balls improve the water quality through adsorption during the water treatment process through the combination of various ceramic components. However, when the ceramic materials are mixed and molded, there is a possibility of wear at high pressure. Since the lifetime of the ceramic balls is short, it is necessary to exchange them at least once a month. In order to obtain the effect of water treatment, water must be treated with ceramic balls for a long time, It is necessary to improve it.

Korean Patent Publication No. 10-0377776 Korean Patent Publication No. 10-0716742 Korean Patent Publication No. 10-1485861

SUMMARY OF THE INVENTION The object of the present invention is to provide a ceramic ball for water treatment capable of maintaining a filtering function and a long life at high water pressure through a ceramic ball manufactured using a composition including a scoria, .

It is also an object of the present invention to provide a ceramic ball which can effectively adsorb and remove harmful substances in water.

In order to solve the above problems, the present invention provides a method of manufacturing a ceramic ball for water treatment, comprising the steps of: preparing a composition comprising scoria, silica (SiO ₂ ), calcium carbonate (CaCO ₃ ), gold (Au) Mixing the slurry into a pressure vessel and subjecting the mixture to a hydrothermal treatment, a drying ball manufacturing step of shaping and drying the hydrothermally treated slurry into a ball shape, drying the dried ball at a temperature of 800 to 1,000 ° C And a step of heat-treating the substrate.

The slurry may be prepared by mixing 50 to 80 parts by weight of scoria, 1 to 20 parts by weight of silica, 1 to 20 parts by weight of calcium carbonate, 0.001 to 10 parts by weight of gold and 0.01 to 10 parts by weight of silver powder Do.

In addition, it is preferable that the step of heat-treating is carried out by raising and lowering the temperature at a rate of 0.5 to 1 占 폚 / min.

The manufacturing method according to the present invention can provide a ceramic ball for water treatment which can maintain filtration function and long life at high water pressure by manufacturing a ceramic ball using a composition including scoria.

In addition, it effectively removes harmful substances from the water to remove water, thereby improving water treatment efficiency.

Hereinafter, the present invention will be described in more detail. The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

The method for producing a ceramic ball for water treatment according to the present invention comprises mixing a composition consisting of scoria, silica (SiO ₂ ), calcium carbonate (CaCO ₃ ), gold (Au) and silver (Ag) powder to prepare a slurry Drying the slurry to form a ball and drying the slurry; and heat treating the dried ball at a temperature of 800 to 1,000 ° C. .

The composition is mainly composed of scoria. The scoria is a porous volcanic clinker having a higher porosity than other volcanic clinkers and has a property of cleaning pollutants and purifying the air including silica, alumina, titanium dioxide and the like .

In the present invention, 300 to 350 mesh scoria powder is used. Table 1 shows the results of analyzing the heavy metal adsorption rate of the scoria powder, yellow mud, mud and charcoal to the New Material Analysis and Evaluation Center of JEOL.

Adsorption time heavy metal Adsorption rate (%) Scoria ocher Charcoal 30 minutes arsenic 8.01 2.36 0.00 30 minutes lead 20.2 7.26 4.51 1 hours arsenic 9.01 0.36 0.00 1 hours lead 20.4 10.30 3.56

As a result of the analysis, it was confirmed that scoria exhibited a similar adsorption rate of arsenic and lead as that of mud, showing excellent adsorption performance.

Table 2 shows the results of analysis of the components of the scoria and mud by the Korea Institute of Construction Materials. In Table 2, the unit is at%.

SiO ₂ Al ₂ O ₃ Fe ₂ O ₃ MgO CaO Na ₂ O TiO ₂ Scoria 45.40 16.87 14.92 6.13 6.95 4.06 3.97 ocher 45.02 38.08 0.76 1.48 1.80 0 0

Analysis of the components of scoria and mud revealed that scoria contained a large amount of components such as iron oxide, magnesium oxide, calcium oxide, sodium oxide and titanium dioxide in comparison with the loess, which shows differences in heavy metal adsorption performance Was identified.

In the present invention, the scoria constituting the composition is preferably contained in a range of 50 to 80 parts by weight. If the content of scoria is too small, the water treatment effect of the ceramic ball is insufficient, and if it is too much, the formability is decreased and the lifetime of the ceramic ball is decreased.

The silica and calcium carbonate are preferably used in the form of a powder having a particle size of 300 to 350 mesh, which is suitable for blending with scoria.

The scoria includes silica in an amount of 45.40 at%. The addition of silica particles separately improves the formability of the ceramic balls, and when the gold and silver particles are supported due to the control of the composition ratio of the scoria itself, The effect was further improved. The silica is contained in an amount of 1 to 20 parts by weight. When the content of silica is too small, there is no difference in effect from the use of scoria alone, and the water treatment effect is insufficient. When the content of silica is excessively high, And the adsorption performance of the component was decreased.

Also, the calcium carbonate is contained in a range of 1 to 20 parts by weight, and serves to improve the moldability of the ceramic ball by controlling the viscosity of the composition when the composition is slurried. When the content of the calcium carbonate is too small, the moldability is deteriorated. When the content of the calcium carbonate is too much, the viscosity is increased and the moldability is decreased.

In addition, it is preferable to use the gold nanoparticles having a particle size of 1 to 100 nm, and the silver particles preferably have a particle size of 1 nm to 10 μm. The gold and silver particles exhibit photocatalytic activity. The gold and silver particles are contained in the composition in an amount of 0.001 to 10 parts by weight and the silver particles are contained in the range of 0.01 to 10 parts by weight. The gold and silver particles are adsorbed on the surfaces of the scoria and silica particles Thereby acting as a cocatalyst. In particular, since the scoria contains titanium dioxide, the gold and silver particles are mixed to exhibit an effect similar to that of the titanium dioxide photocatalyst carrying the promoter.

Such a composition may be mixed with water to prepare a slurry. When preparing the slurry, it is not necessary to specifically adjust the viscosity, and it may be formulated in a range of 50 to 200 parts by weight based on 100 parts by weight of the composition.

Since the diluted slurry can not be formed as it is, it is subjected to hydrothermal treatment in a pressure vessel. The hydrothermal treatment is carried out for 1 to 24 hours, during which the homogeneous mixing of the composition and the loading of gold and silver powder are carried out.

The hydrothermally treated slurry can be formed into a ball shape by compression molding or electrotransfer assembly. The ceramic ball is preferably shaped to have a diameter of 2 to 10 mm, considering the efficiency of the water treatment and the size for putting it into various types of water treatment apparatuses.

The scoria contained in the ceramic ball is a porous particle. Porosity is imparted to the ceramic ball itself by heat-treating the ceramic ball produced by molding the composition. Thus, the adsorption efficiency is improved so that harmful substances in the water and bacteria can be adsorbed through the ceramic balls.

For this purpose, the formed ceramic balls are subjected to hot air drying until the water content becomes less than 2%. If the moisture content is too low, cracks or breakage of the ceramic balls may occur. However, even if the water content is high, it is preferable to adjust the moisture content to 1 to 2% because cracks are generated in the high temperature heat treatment process.

The thus-prepared dried ceramic ball is heat-treated at a temperature of 800 to 1,000 ° C to obtain strength and porosity. The heat treatment is performed at the above temperature for 1 to 20 hours, preferably 1 to 10 hours. If the heat treatment time is too long, the density of the ceramic balls increases and the surface area and the porosity are decreased. Therefore, it is not suitable for the water treatment and sufficient durability can not be obtained even if the heat treatment time is too short.

In particular, it is necessary to optimize the heating and cooling rates in the heat treatment process. In the present invention, the heating rate and the cooling rate are set to 0.5 to 1 占 폚 / min, respectively. If the heating and cooling rate is too slow, the productivity decreases. If the temperature is raised or lowered faster than the heating and cooling rate, sufficient pore volume can not be secured, which is unsuitable for water treatment.

In order to confirm the effect of the manufacturing method according to the present invention, experiments were conducted to change the process conditions.

Silica, and calcium carbonate powder having a particle size of 325 mesh, and gold particles having an average particle size of 60 nm and silver particles having an average particle size of 3 μm were prepared, and 60 parts by weight of scoria, 12 parts by weight of silica, 10 parts by weight of calcium carbonate, , 0.1 part by weight of the particles, and 0.2 part by weight of the silver particles, 80 parts by weight of water was added to 100 parts by weight of the mixed powder, and the mixture was stirred for 30 minutes to prepare a slurry.

The prepared slurry was put into a pressure vessel and heated and hydrothermally treated for 18 hours. A ceramic ball having a diameter of 5 to 8 mm was prepared by the above-mentioned hydrothermally treated slurry by means of electric motor assembly.

The ceramic balls were hot-air dried and then charged into a calciner. The ceramic balls were manufactured by changing the process conditions of the drying and the heat treatment process to the conditions as shown in Table 3.

Moisture content
(%) Heating rate
(° C / min) Cooling rate
(° C / min) Heat treatment temperature
(° C) Heat treatment time
(time) Experiment 1 1.5 0.8 0.8 800 5 Experiment 2 1.5 1.5 1.5 800 5 Experiment 3 1.4 2 2 1000 5 Experiment 4 1.6 1.5 1.5 1000 24 Experiment 5 1.2 0.8 0.8 800 24 Experiment 6 2.6 0.8 0.8 800 5 Experiment 7 2.8 1.5 1.5 1000 5 Experiment 8 2.5 0.8 0.8 1000 24

The prepared ceramic balls were filled in a lock filter and exposed to water pressure of 10.0 kg / cm 2 for 24 hours. After the experiment, the ceramic balls were recovered and dried, and the weight loss ratio before and after use was measured. In addition, a part of the ceramic balls was pulverized and the specific surface area was measured by the nitrogen adsorption method, and the water absorption rate was measured according to KRL 3114: 2005. The results are shown in Table 4.

Specific surface area (m < 2 > / g) Water Absorption Rate (%) Weight reduction rate (%) Experiment 1 15.4 53.5 0.1 Experiment 2 7.6 38.8 0.2 Experiment 3 6.8 36.6 0.1 Experiment 4 10.8 40.2 0.1 Experiment 5 12.0 42.8 0.1 Experiment 6 14.8 52.5 1.2 Experiment 7 6.8 40.2 1.0 Experiment 8 6.5 37.2 0.8

As shown in Table 4, in Experiment 1, the specific surface area and water absorption rate of the ceramic balls were high, and it was found that the durability was excellent because the weight reduction rate was low before and after the high pressure water treatment. On the other hand, Experiments 6 to 8, in which the temperature increase and the temperature decrease rate were fast, showed a good water absorption rate but a large weight loss rate before and after the high pressure water treatment, which means a loss of the ceramic balls and a relatively low durability.

In addition, when the heating rate is fast or the heat treatment is performed for too long, the specific surface area and the water absorption rate are decreased as compared with Experiment 1, and the optimum effect is obtained only under proper process conditions.

Next, the composition was changed and the experiment was conducted under the optimum process conditions. The production method of the ceramic balls was according to Experiment 1, and the compositions of the compositions are shown in Table 5. In Table 5, the unit is parts by weight.

Scoria ocher Ilright Silica Calcium carbonate gold silver Experiment 1 60 12 10 0.1 0.2 Experiment 9 60 15 0.1 0.2 Experiment 10 60 10 10 0.2 Experiment 11 60 10 10 0.2 Experiment 12 60 10 10 0.1 0.15 Experiment 13 60 10 10 0.1 0.15

Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 6538P) were used as test strains in order to confirm the strain adsorption performance. The test strain was inoculated in 5 ml of the culture medium for 16 hours, and 0.1 ml of the culture medium of the test strain was mixed with 0.1 ml of the culture broth containing 0.03% by weight of the powder. For 16 hours, and counted viable cells by standard plate culture method. The culture of the test strain was also used as a control. The results are shown in Table 6.

ATCC 25922 (CFU / ml) ATCC 6538P (CFU / ml) Control group 5 × 10 ⁷ 2.5 x 10 ⁸ Experiment 1 2.2 x 10 ⁹ 1.4 x 10 ⁹ Experiment 9 4.5 × 10 ⁸ 1.0 × 10 ⁸ Experiment 10 1.5 × 10 ⁸ 6.8 × 10 ⁹ Experiment 11 2.5 x 10 ⁸ 4.8 × 10 ⁹ Experiment 12 1.0 x 10 ⁷ 8.5 × 10 ⁹ Experiment 13 8.8 × 10 ⁸ 5.5 × 10 ⁹

As shown in Table 6, in Experiment 1, E. coli and Staphylococcus aureus were significantly decreased compared with the control group. This is attributed to the adsorption by the ceramic balls of the present invention and the death of the strain. On the other hand, in Experiments 9 to 11 in which the composition and ratio of the composition were changed, the reduction rate of E. coli and Staphylococcus aureus was lower than that of Experiment 1, In comparison, the reduction rate of Escherichia coli and Staphylococcus aureus was low, indicating that there was a significant difference in water treatment effect according to the optimum composition.

It is to be understood that the invention is not limited to the disclosed embodiment, but is capable of many modifications and variations within the scope of the appended claims. It is self-evident.

Claims (3)

300 to scoria (scoria) of 350 mesh 50 to 80 parts by weight, from 300 to silica of 350 mesh (SiO ₂₎ 1 to 20 parts by weight of calcium carbonate (CaCO ₃₎ of 300 to 350 meshes of 1 to 20 parts by weight, and 1 to 0.001 to 10 parts by weight of gold (Au) powder of 100 nm in size and 0.01 to 10 parts by weight of silver (Ag) powder of 1 nm to 10 탆 are mixed with 50 to 200 parts by weight of water to prepare a slurry ;
Introducing the slurry into a pressure vessel and hydrothermally treating the slurry;
A drying ball manufacturing step of shaping the hydrothermally treated slurry into a ball shape and drying the ball;
Heat treating the dried balls at a temperature of 800 to 1,000 ° C;
/ RTI >
Wherein the heat treatment step comprises raising and lowering the temperature at a rate of 0.5 to 1 占 폚 / min. delete delete