KR20170123044A - Compound semi-permeable system for removing radionuclide using carrier containing microalgae - Google Patents

Abstract

The present invention relates to a system for removing a radioactive material from radioactively contaminated water and, more specifically, to a compound semi-permeable membrane system for removing a radioactive material using a carrier containing microalgae. The compound semi-permeable membrane system for removing a radioactive material using a carrier containing microalgae comprises: an accommodation unit accommodating a carrier carrying microalgae, wherein the whole or a portion thereof is positioned in radioactively contaminated water; the carrier which carries the microalgae, allows a radionuclide to pass therethrough, and does not allow the microalgae to pass therethrough; the microalgae carried by the carrier to absorb the radionuclide to remove the radionuclide from the radioactively contaminated water; and a semi-permeable membrane formed on the whole or a portion of the accommodation unit to allow the radionuclide to pass therethrough and prevent the microalgae from passing therethrough. The radionuclide contained in the radioactively contaminated water sequentially passes through the semi-permeable membrane and the carrier to react to the microalgae to be removed from the radioactively contaminated water. Since the microalgae absorbing the radionuclide cannot pass through the carrier, a contaminated material can be effectively prevented from being re-discharged.

Description

[0001] The present invention relates to a composite semi-permeable membrane system for removing radioactive materials using a carrier containing microalgae,

The present invention relates to a system for removing radioactive material from radioactive contaminated water, and more particularly, to a system for removing radioactive material from radioactive contaminated water, comprising a receiving part for receiving a carrier carrying all or a part of the radioactive contaminated water, A carrier which does not allow the radioactive nuclide to pass but does not allow the microalgae to pass therethrough; and micro-algae that are carried on the carrier to absorb radionuclides and remove radionuclides from the radioactive contaminated water, Wherein the radionuclide contained in the radioactive contaminated water, including the semi-permeable membrane that does not pass the microalgae, passes through the semi-permeable membrane and the carrier in order, reacts with the microalgae to be removed from the radioactive contaminated water, Since one microalgae can not pass through the carrier, By effectively using a carrier containing the micro-algae capable of preventing is for a composite semi-permeable membrane system for the removal of radioactive material.

As the use of nuclear energy increases in various fields such as power generation, medical and industrial sectors, the amount of radioactive waste increases, causing environmental and social problems. In addition, the large amount of radionuclides released from nuclear accident at Chernobyl, Fukushima, etc. has already reached the highest level and is causing a wide range of environmental pollution. Even low-level radioactive waste is extremely hazardous to humans and the environment, so proper disposal at the time of disposal is required. Accordingly, in order to solve the problem of environmental pollution caused by the radioactive waste (waste liquid), recently, a method of treating radioactive waste using microalgae has been developed as in the following patent document.

<Patent Literature>

Patent Publication No. 10-2015-0003619 (published on May 01, 2015) "Method of removing radionuclides using microalgae"

However, in the conventional microalgae method, it is possible to remove radionuclides in an environmentally friendly manner. However, in the case of purifying a large amount of polluted water by directly applying microalgae to the polluted area, microalgae absorbing radionuclides are separated from the polluted area There is a difficult problem to do.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems,

The present invention relates to a composite semi-permeable membrane for removing radioactive materials by using a carrier containing fine algae capable of easily separating and collecting microalgae reacted with radionuclides, The purpose of the system is to provide.

The present invention also relates to the use of a carrier containing fine algae capable of spatially separating microalgae reacted with radionuclides using a semi-permeable membrane which can pass through the radioactive nucleus but can not pass microalgae, And to provide a composite semipermeable membrane system for removing water.

The present invention also provides a microalgae capable of passing radioactive nuclides but not microalgae through which microalgae are located and further preventing microalgae from reacting with pollutants. Permeable membrane system for removing radioactive materials by using a carrier containing a surfactant.

Another object of the present invention is to provide a composite semipermeable membrane system for removing radioactive materials by using a carrier containing microalgae capable of increasing the survival time of microalgae because microalgae are located in alginate beads .

The present invention also relates to a method for producing a radioactive material by using a composite semipermeable membrane such as a composite of kapok fiber and a nylon mesh or a composite of a nonwoven fabric and a nylon mesh to thereby further improve the removal efficiency of the contaminant, The present invention provides a composite semi-permeable membrane system for removing a membrane.

In order to achieve the above object, the present invention is implemented by the following embodiments.

According to an embodiment of the present invention, a semi-permeable membrane system for removing radioactive material according to the present invention includes: a receiving part for receiving a carrier carrying micro-algae, all or part of which is located in the radioactive contaminated water; A carrier that supports the microalgae and does not allow the radionuclide to pass through the microalgae; A micro-algae carried on the carrier to absorb radionuclides and remove radionuclides from the radioactive contaminated water; And a semi-permeable membrane formed on all or a portion of the receiving portion, the semi-permeable membrane passing the radionuclide but not the microalgae, wherein the radionuclide contained in the radioactive contaminated water passes through the semi-permeable membrane and the carrier in order And is reacted with the microalgae to be removed from the radioactive contaminated water.

According to another embodiment of the present invention, in the semi-permeable membrane system for removing radioactive material according to the present invention, alginate beads are used as the carrier and microalgae are located in the alginate beads.

According to another embodiment of the present invention, in the semi-permeable membrane system for removing radioactive material according to the present invention, the carrier has a diameter of 2 to 5 mm.

According to another embodiment of the present invention, in the semi-permeable membrane system for removing radioactive material according to the present invention, alginate beads carrying microalgae are prepared by mixing microalgae with an alginate solution to prepare a mixed solution, And dropping the mixed solution into the solution.

According to another embodiment of the present invention, in the semi-permeable membrane system for removing radioactive material according to the present invention, the semi-permeable membrane has a plurality of micropores having a diameter of 0.45 to 1 μm.

According to another embodiment of the present invention, in the semi-permeable membrane system for removing radioactive material according to the present invention, the semi-permeable membrane is formed of any one of a polymer membrane or a fiber material membrane having a semi-permeable property.

According to another embodiment of the present invention, in the semi-permeable membrane system for removing radioactive material according to the present invention, the semi-permeable membrane is formed of a composite of kapok fiber and nylon membrane.

According to another embodiment of the present invention, in the semi-permeable membrane system for removing radioactive material according to the present invention, the radionuclide is cesium-137 or strontium-90. do.

According to another embodiment of the present invention, in the semi-permeable membrane system for removing radioactive material according to the present invention, the microalgae are microalgae of the genus Chlorella or of the genus Hematococcus.

According to another embodiment of the present invention, in the semipermeable membrane system for removing radioactive material according to the present invention, the receiving part surrounds the carrier, and a semi-permeable membrane is formed on one side, and a radionuclide and microalgae The receiving portion can be removed from the radioactive contaminated water to separate the carrier carrying the microalgae that absorb the radionuclide in the receiving portion, and the receiving portion has a cylindrical shape in which the carrier is received, And a semi-permeable film is formed on the lower surface of the receiving portion.

According to the present invention, the following effects can be obtained by this embodiment.

The present invention is capable of easily separating and collecting microalgae reacted with radionuclides, thereby facilitating the purification of a large amount of radioactive contaminated water.

In addition, the present invention has an effect of spatially separating microalgae reacted with radionuclides using a semi-permeable membrane through which radioactive nuclear species can pass but microalgae can not pass through.

In addition, the present invention has the effect of further preventing the microalgae from locating in the carrier (alginate bead) through which the radionuclide can pass but the microalgae can not pass through, thereby further releasing the microalgae reacted with the pollutant .

In addition, since the microalgae are located in the alginate beads, the present invention has the effect of increasing the survival time of the microalgae.

Further, the present invention has the effect of further improving the removal efficiency of contaminants by using composite semipermeable membranes such as a composite of kapok fiber and nylon mesh, and a composite of nonwoven fabric and nylon mesh.

1 is a schematic diagram illustrating a semi-permeable membrane system in accordance with an embodiment of the present invention.
2 is a schematic diagram showing the principle of radioactive decontamination in the semi-permeable membrane system of FIG. 1;
FIGS. 3 and 4 are reference views for explaining an experimental method using a transflective film system according to an embodiment of the present invention;
FIG. 5 is a graph showing experimental results using a semi-permeable membrane system according to an embodiment of the present invention. FIG.

Hereinafter, a composite semipermeable membrane system for removing radioactive materials using a carrier containing microalgae will be described in detail with reference to the accompanying drawings. Unless defined otherwise, all terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs and, if conflict with the meaning of the terms used herein, It follows the definition used in the specification. Further, the detailed description of known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted. Throughout the specification, when an element is referred to as "including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise.

The composite semipermeable membrane system for removing radioactive materials using a carrier containing microalgae according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. The semipermeable membrane system includes a radioactive contaminated water 100 (1) for receiving the carrier (2) carrying the microalgae (3); A carrier 2 which carries the fine algae 3 and which does not allow the radionuclide 110 to pass through and the fine algae 3; A fine algae 3 carried by the carrier 2 to absorb the radionuclide 110 to remove the radionuclide 100 from the radioactive contaminated water 100; And a semi-permeable membrane (4) formed on all or a portion of the receiving part (1), the semi-permeable membrane (4) passing the radionuclide (110) but not passing the microalgae (3) The radionuclide 110 included in the radionuclide 110 sequentially passes through the transflective film 4 and the carrier 2 and reacts with the microalgae 2 to be removed from the radioactive contaminated water 100, The micro-algae 3 absorbing the micro-algae 3 can not pass through the carrier 2, so that the micro-algae 3 can effectively prevent re-emission of pollutants.

The accommodating portion 1 is configured such that all or a part of the accommodating portion 1 is accommodated in the radioactive contaminated water 100 and the carrier 2 carrying the microalgae 3 is accommodated. And a transmissive film 4. The receiving portion 1 has a certain shape but preferably has a form in which the carrier 2 carrying the microalgae 3 is surrounded and the semipermeable membrane 4 is formed on one side, Permeable membrane (4) is formed on the lower surface of the receiving portion (1) with a cylindrical shape accommodating the carrier (3) therein. The radioactive contaminated water 100 includes a radionuclide such as cesium-137, strontium-90, or iodine-131.

The carrier 2 is positioned in the receiving part 1 and supports the microalgae 3 so that the microalgae 3 can pass through the radionuclide 110 but not through the microalgae 3, So that it can survive stable. For example, the carrier 2 can be alginate beads and microalgae are located in the alginate beads. The alginate beads carrying the fine algae 2 have a certain diameter but preferably have a diameter of 2 to 5 mm. The alginate beads carrying the microalgae are prepared by adding sodium alginate to distilled water and stirring the mixture for a predetermined period of time to prepare an alginate solution. The microalgae are mixed with an alginate solution to prepare a mixed solution, Can be dropped to produce alginate beads carrying microalgae.

The fine algae 3 are supported on the carrier 2 and react with the radionuclide 110 to absorb radionuclides to remove radionuclides 110 from the radioactive contaminated water 100 , Various microalgae capable of removing radionuclides will be used. As an example, the microalgae are those of the genus Chlorella or of the genus Haematococcus , and the species of the genus Chlorella is Chlorella anitrata), Chlorella hits Kirk Utica (Chlorella antarctica), Chlorella brother Leo corruption disk (Chlorella aureoviridis), Chlorella Candida (Chlorella Candida), Chlorella capsule rata (Chlorella capsulata), Chlorella desik Catarina (Chlorella desiccata), Chlorella IDEA ellipsometer (Chlorella ellipsoidea), Chlorella Aime Le soniyi (Chlorella emersonii , Chlorella fusca ), Chlorella fusca var. Chlorella There is fusca . vacuolata), Chlorella glucoside Trojan file (Chlorella glucotropha), Chlorella inpyu Please num (Chlorella infusionum ), Chlorella infusium var. Chlorella I have infusion . Actophila ), Chlorella infusium var. Chlorella I have infusion . Auxenophila), Chlorella Kessler Li (Chlorella kessleri ), Chlorella luteoviridis , Chlorella luteoviridis var. Chlorella luteoviridis var. Aureoviridis , Chlorella luteoviridis var. Ruthenate sense (Chlorella luteoviridis var. Lutescens), Chlorella mini-Ata (Chlorella miniata), Chlorella minu Tea Island (Chlorella minutissima ), Chlorella mutabilis , Chlorella nocturna , Chlorella parva , Chlorella photophila), Chlorella spring years already (Chlorella pringsheimii), Chlorella Teco protocol id (Chlorella protothecoides), Chlorella regyulra less (Chlorella regularis ), chlorella regularis var. Chlorella There is regularis . minima ), chlorella regularis var. Umbrian Kata (Chlorella regularis var. Umbricata), Lacey geulriyi Chlorella (Chlorella reisiglii), Pilar (Chlorella Chlorella as Saccharomyces Saccharophila), Chlorella saccharophila var. Chlorella There is saccharophila . ellipsoidea), Salina Chlorella (Chlorella salina), Chlorella simplex (Chlorella simplex), Chlorella Thoreau Kearney Ana (Chlorella sorokiniana), Chlorella Spa Erica (Chlorella sphaerica), Chlorella stigmasterol Sat Fora (Chlorella stigmatophora , Chlorella vanniellii , Chlorella vulgaris ), chlorella bulgaris f. Tertia ( Chlorella vulgaris f. Tertia ), Chlorella vulgaris var. Iridis ( Chlorella vulgaris var. Airidis ), Chlorella vulgaris var. Bulgarian ( Chlorella vulgaris var. Vulgaris ), Chlorella vulgaris var. Bulgaris F. Chlorella There is vulgaris . vulgaris f. tertia ), Chlorella vulgaris var. Bulgaris F. Chlorella There is vulgaris . vulgaris f. viridis ), chlorella xanthia ( Chlorella xanthella), and Chlorella crude pinji N-Sys (Chlorella zofingiensis) which has one or more may be used, the hematoxylin nose kusu genus species hematoxylin nose kusu kapen sheath (Haematococcus capensis) is selected from the group consisting of hematoxylin nose kusu Caro The strains of Haematococcus carocellus, Haematococcus droebakensis, Haematococcus lacustris, Haematococcus murorum, Hematococcus fluvialis, Haematococcus pluvialis, Haematococcus thermalis, Haematococcus zimbabwiensis, Haematococcus obtusis pinus, Haematococcus insignis, ), Haematococcus truncatispinus, Haematococcus salinus, Hematococcus sanguineus Haematococcus sanguineus, Haematococcus allmanii, and Haematococcus buetschlii can be used. Preferably chlorella Thoreau Kearney Ana (Chlorella sorokinianna or Chlorella vulgaris ) or Haematococcus pluvialis are used. Removable radionuclides include cesium-137, strontium-90, iodine-131, uranium-238, barium-133, cadmium-109, cobalt -57), Cobalt-60, Europium-152, Manganese-54, Sodium-22, Zinc-22, Technetium-99m, Thallium- 204, Polonium-210, Americium-241, Iodine-131, and the like. The carrier 2 carrying the microalgae 3 is mixed with the buffer solution and placed in the receiving part 1. The buffer solution may be NaHCO ₃ Buffer solutions, buffer solutions containing NaHCO ₃ , NaNO ₃ and NaCl, and the like, but are not limited thereto. The buffer solution is preferably composed of pure basic buffers excluding various nutrients. This can be a parameter for analyzing adsorption and absorption of radionuclides by microalgae in the presence of excessive nutrients and other ions, Unnecessary components are excluded because the self-precipitation of radionuclides can occur through reaction with various elements in the buffer solution.

The semi-permeable membrane (4) is formed on all or a part of the receiving portion (1) so that the radionuclide (110) passes but does not pass microalgae The radioactive nuclides 110 contained in the radioactive nuclides 110 pass through the transflective film 4 and react with the microalgae 4 carried on the carrier 2 to be removed from the radioactive contaminated water 110, The carrier 2 on which the microalgae 2 having absorbed the ultrafine algae 110 are carried is spatially separated by the receiving part 1. The semi-permeable membrane 4 is made of a certain material, and is preferably made of any one of a polymer membrane or a fiber material membrane having a semi-permeable property, more preferably a cellulose acetate, a polyvinylidene fluoride, a hydrogel, And nylon. If the diameters of the micro pores of the semi-permeable membrane are less than 0.45 μm, the radionuclide can not be passed. If the diameters of the semi-permeable membrane are larger than 1 μm, micro-algae can pass therethrough and the diameters of the micropores of the semi-permeable membrane are preferably 0.45 to 1 μm .

The semi-permeable membrane 4 may be formed of a composite material of various materials, for example, a composite of kapok fiber and nylon membrane, a composite of nonwoven fabric and nylon membrane, or the like. The Kapok fibers have a buoyancy of 35 times the weight and are strong in oil adhesion force and are effective in removing heavy metals. Separation of the alginate beads from the kapok fibers is easy and the composite of kapok fibers and nylon membranes has good ion permeability , And kapok fiber can be used repeatedly. Further, in the case of a semi-permeable membrane bonded with a nylon membrane and a nonwoven fabric, the ion permeability is good and the re-discharge of microalgae can be effectively prevented. A method of purifying the radioactive contaminated water using the semi-permeable membrane system, that is, a method of removing the radionuclide from the radioactive contaminated water, includes a step of immersing the carrier 3 carrying the microalgae 3, The carrier (microalgae) can not move through the semi-permeable membrane 4, but the radionuclide 110 is permeable to the semi-permeable membrane 4, the carrier 2, The radionuclide 110 present in the radioactive contaminated water 100 passes through the semi-permeable membrane 4 and the carrier 2 formed in the receiving part 1 in order and passes through the inside of the carrier 2 And is adsorbed on the microalgae 3 and is removed from the radioactive contaminated water 100. The carrier 2 on which the fine algae 3 loaded with the radionuclide 110 in the accommodating portion 1 is lifted can be easily separated from the radioactive contaminated water 100 by lifting the accommodating portion 1 from the radioactive contaminated water 100, So that it is possible to easily purify a large amount of radioactive contaminated water. The present invention can be applied not only to the removal of radionuclides but also to the removal of harmful heavy metals.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, these are only for the purpose of illustrating the present invention in more detail, and the scope of the present invention is not limited thereto.

<Examples> Production of alginate beads carrying microalgae

(1) Sodium alginate was added to distilled water and stirred for 1 hour to prepare a 1% alginate solution. The chlorella blueless washed with ₃ mM NaHCO ₃ was separated by centrifugal separation and mixed with the alginate solution. Prepare.

(2) The mixture solution was dropped into a 1% calcium chloride solution using a pipette and reacted for 1 hour. The reaction mixture was washed with ₃ mM NaHCO ₃ and dried to obtain microalgae as shown in FIG. 3 (a) To thereby prepare a supported alginate bead (sample 1).

&Lt; Comparative Example > Preparation of alginate beads

(1) Add alginate sodium to distilled water and stir for 1 hour to prepare 1% alginate solution.

(2) The alginate solution was dropped to a 1% calcium chloride solution using a pipette and allowed to react for 1 hour. The reaction product was washed with ₃ mM NaHCO ₃ and dried to obtain alginate beads as shown in FIG. 3 (b) Sample 2) was prepared.

<Experimental Example> Determination of radioactive removal effect of alginate beads carrying microalgae

(1) A lower portion of a polycarbonate container was cut by 1 cm, and a 1 um nylon mesh and a nonwoven fabric (7 x 7 cm) were bonded to the container using a non-toxic, water-based silicone adhesive to form a container having a semi-permeable membrane. Place the sample 1 on the receiving portion, the receiving portion when 300mL 100ppb Sr (NO ₃₎ is filled, Sr (NO _{3) 2} aqueous solution of 100mL inside the receiving portion was placed on the filled beaker ₂ aqueous solution, a 50mL beaker Sr (see (a) of Fig. 4) (NO ₃₎ further adding a _second aqueous solution to the reaction, and after the reaction of 1, 5, and 10 days taken for the solution in the beaker of the last time to analyze a sample by ICP-OES The results are shown in Fig. In the result of analysis, the initial Sr ion concentration was not correct in the result, and the results were analyzed by converting the quantitative value of Sr ion concentration to%.

(2) The same experiment as in Experimental Example (1) was performed except that Sample 2 was added instead of Sample 1 (see Fig. 4 (b)).

(3) FIG. 5 shows that when Sample 1 was used after 5 days of incubation, the removal rate of Sr ion was 27%, whereas that of Sample 2 was 21% of Sr ion removal rate. After 10 days of incubation, The removal rate of Sr ion was 44%, whereas the removal rate of Sr ion was 28% using sample 2. Through this, it can be seen that the radionuclide passing through the carrier reacts with the microalgae and is removed from the radioactive contaminated water.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Should be interpreted as belonging to the scope.

1: receptacle 2: carrier 3: microalgae
4: carrier 100: radioactive contaminated water 110: radionuclide

Claims (10)

An accommodating portion in which all or a part of the radioactive contaminated water is located and accommodates a carrier carrying microalgae; A carrier that supports the microalgae and does not allow the radionuclide to pass through the microalgae; A micro-algae carried on the carrier to absorb radionuclides and remove radionuclides from the radioactive contaminated water; And a semi-permeable membrane formed on all or a part of the receiving portion, the semi-permeable membrane passing the radionuclide but not passing microalgae,
Wherein the radionuclide contained in the radioactive contaminated water passes through the transflective membrane and the carrier in order and reacts with the microalgae to be removed from the radioactive contaminated water. The method according to claim 1,
Characterized in that the carrier is an alginate bead, wherein microalgae are located in the alginate bead. 3. The method of claim 2,
Wherein said carrier has a diameter of 2 to 5 mm. &Lt; RTI ID = 0.0 &gt; 8. &lt; / RTI &gt; 3. The method of claim 2, wherein the alginate beads carrying the microalgae
Wherein the mixed solution is prepared by mixing the microalgae with the alginate solution and dropping the mixed solution into the calcium chloride solution by dropping droplets. The method of claim 3, wherein the semi-
Wherein the membrane has a plurality of micropores having a diameter of 0.45 to 1 占 퐉. The method of claim 5, wherein the semi-
Wherein the semi-permeable membrane system comprises any one of a polymer membrane or a fiber membrane having semi-permeability characteristics. The method of claim 1, wherein the semi-
Wherein the semi-permeable membrane system is formed of a composite of kapok fibers and nylon membranes. The method of claim 1, wherein the radionuclide comprises
Characterized in that the semi-permeable membrane system comprises cesium-137 or strontium-90. The method of claim 1, wherein the microalgae
Characterized in that it is a microalgae of the genus Chlorella or of the genus Hematococcus. The method according to claim 1,
Wherein the receiving portion encircles the carrier and has a semi-permeable membrane formed on one side thereof. After the radioactive nuclide and the microalgae react for a predetermined period of time, the receiving portion is removed from the radioactive contaminated water to absorb the radioactive nuclide in the receiving portion, The carrier can be separated,
Wherein the receiving portion has a cylindrical shape for receiving a carrier therein, and a semi-permeable film is formed on a lower surface of the receiving portion.

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