METHOD FOR THE AEROBIC AND ANAEROBIC CULTIVATION OF MICROORGANISMS, METHOD FOR THE PRODUCTION OF A PREPARATION FOR CLEANING RADIOACTIVE LIQUIDS AND RADIOACTIVELY CHARGED SURFACES, METHOD FOR CLEANING RADIOACTIVE LIQUIDS AND METHOD FOR CLEANING RADIO-ACTIVELY CHARGED SURFACES

Abstract

The invention relates to a method for aerobic and anaerobic cultivation of microorganisms. The invention also relates to a method for producing a preparation for cleaning radioactive liquids and radioactively charged surfaces. Likewise, the invention further relates to a method for cleaning radioactive liquids and radioactively charged surfaces.

Claims

1. A method for the aerobic cultivation of microorganisms, comprising the steps of: providing an aqueous solution having a pH value of 5.5 to 9.0 in a container, adding a substrate in a first substrate dosage to the aqueous solution, adding further elements to the aqueous solution, adding an inoculant with microorganisms to the aqueous solution, wherein an initial product is provided by the abovementioned steps, and wherein, subsequently, the following steps are performed: introducing air into the initial product or into intermediate products developing therefrom, varying a temperature of the initial product or the intermediate products developing therefrom in a range from 15 to 35° C., wherein, after having added the substrate in the first substrate dosage, the following steps are performed for monitoring the cultivation: taking a reference liquid sample and determining a first concentration of organic substance in the reference liquid sample, taking another liquid sample and determining another concentration of organic substance in the further liquid sample after the expiration of the first waiting time, if the further concentration of organic substance is smaller than 10 percent of the first concentration of organic substance, adding substrate in another substrate dosage, repeating the abovementioned steps for monitoring the cultivation until a sufficient amount of biomass is present in the container.

2. (canceled)

3. The method according to claim 1, wherein, a sufficient amount of biomass is present in the container when 50 g of wet biomass are extractable from one litre of product volume, wet biomass having a moisture content of 93 to 99 percent.

4. The method according to claim 1, wherein the aqueous solution is based on deionised water.

5. The method according to claim 1, wherein glucose or saccharose or ethanol or methanol are used as the substrate.

6. The method according to claim 1, wherein the first substrate dosage is added in a concentration of 0.5 g/l/d to 2 g/l/d, claim 1, and the further substrate dosages are added in a concentration of 0.5 g/l/d to 2 g/l/d, respectively in relation to the volume of the aqueous solution.

7. The method according to claim 1,wherein microelements or macroelements are added as further elements, wherein the wherein the microelements are selected from the group of Mn, Mo, Zn, Cu, Co, Ni, Cl, Br, and wherein the macroelements are selected from the group of C, H, O, N, S, K, Ca, P, Mg, Fe.

8. The method according to claim 6, wherein the microelements are added in a concentration of 0.5 .sup.∗ 10-5 g/l to 2 .sup.∗ 10-5 g/l and the macroelements in a concentration of 0.5 g/l to 2 g/l, respectively in relation to the volume of the aqueous solution.

9. The Method according to claim 1 wherein the inoculant contains bacteria claim 1, or fungy or protozoa.

10. The method according to claim 1, wherein the inoculant is added in a concentration of 5 to 10 percent in relation to the volume of the aqueous solution.

11. The method according to claim 1, wherein air is introduced during predetermined periods of time and that no air is introduced outside of these predetermined periods of time.

12. The method according to claim 11, wherein the rate of introduced air in relation to one litre of the volume of the initial product is from 1 l/min to 2 l/min.

13. A method for the production of a preparation for cleaning radioactive liquids and surfaces, comprising the steps of: providing of a substance with aerobic microorganisms, cultivated using a method aerobic of cultivation of microorganisms comprising the steps of: providing an aqueous solution having a pH value of 5.5 to 9.0 in a container. adding a substrate in a first substrate dosage to the aqueous solution, adding further elements to the aqueous solution, adding an inoculant with microorganisms to the aqueous solution, wherein an initial product is provided by the abovementioned steps, and wherein, subsequent, the following steps are performed: introducing air into the initial product or into intermediate products developing therefrom, varying a temperature of the ínitial product or the intermediate products developing therefrom in a range from 15 to 35 degree Celsius, wherein, after having added the substrate in the first substrate dosage, the following steps are perfomed for monitoring the curtivation: taking a reference liquid sample and determining a first concentration of organic substance in the reference liquid sample. taking another liquid sample and determining another concentration of organic substance in the further liquid sample after the expiration of the first waiting time, if the further concentration of organic substance is smaller than 10 percent of the first concentration of organicsubstance, adding substrate in another substrate dosage. repeating the abovementioned steps for monitoring the cultivation until a sufficient amount of biomass is present in the container, or providing of a substance with anaerobic microorganisms, particularly cultivated according to one of the claims 2 to 10 cultivated using a method for the anaerobic cultivation of microorganisms, comprising the steps of: providing an aqueos solution having a pH value of 4.5 to 7.5 in a container adding a substrate in a first substrate dosage to the aqueous solution, adding further elements to the aqueous solution, adding an inoculant with microorganisms to the aqueous solution, wherein an initial product is provided by the abovementioned steps, and wherein, subsequently, the following steps are performed: hermetically sealing the container, varying a temperature of the initial product or the intermediate products developing therefrom in a a range from 40 to 80° C., wherein, after having added the substrate in the first substrate dosage, the following steps are performed for monitoring the cultivation: taking a reference liquid sample and determining a first concentration of organic subtance in the reference liquid sample, taking another liquid sample and another concentration of organic substance in the further liquid sample after the expiration of the first waiting time, if the further concentration of organic substance is smaller than 10 percent of the first concentration of organic substance, adding substrate in another substrate dosage, repeating the abovementioned steps for monitoring the cultivation until a sufficient amount of biomass is present in the container, wherein the substance is subjected to the following steps for washing: centrifuging the substance for producing wet biomass, adding an isotonic solution to the wet biomass for producing a washed substance, wherein the steps for washing are repeated a plurality of times, if required, to thereby provide the preparation for cleaning radioactive liquids and surfaces.

14. The method according to claim 13, wherein the substance with aerobic microorganisms and the substance with anaerobic microorganisms are mixed prior to being washed.

15. The method according to claim 13, wherein, after washing, an analysis of the washed biomass is carried out.

16. The method according to claim 13, wherein the preparation for cleaning radioactive liquids and surfaces is filled into water-permeable cartridges in portions.

17. The method according to claim 13, wherein the preparation for cleaning radioactive liquids and surfaces is dried by means of lyophilisation.

18. A method for cleaning radioactive liquids, comprising the steps of: providing radioactive liquid to be cleaned in a reactor, adding a preparation for cleaning radioactive liquids into the reactor, the preparation produced by a method for the production of a perparation for cleaning radioactive liquids and surfaces comprising providing of a substance with aerobic microorganisms, particularly cultivated comprising the steps of: providing an aqueous solution having a pH value of 5.5 to 9.0 in a container adding a substrate in a first substrate dosage to the aqueous solution, adding further elements to the aqueous solution, adding an inoculant with microorganisms to the aqueous solution, wherein an initial product is provided by the abovementioned steps, and wherein, subsequently, the following steps are performed: introducing air into the initial product or into intermediate products developing therefrom, varying a termperature of the initial product or the intermediate products developing therefrom in a range from 15 to 35 degrees Celsuis, wherein, after having added the substratae in the first substrate dosage, the following steps are performed for monitoring the cultivation: taking a reference liquid sample and determining a first concentration of organic substance in the reference liquid sample, substance in the reference liquid sample, taking another liquid sample and determining another concentration of organic substance in the further liquid sample after the expiration of the first waiting time, if the further concentration of organic substance is smaller than 10 percent of the first concentration of organic susbtance, adding substrate in another substrate dosage, repeating the abovementioned steps for monitoring the cultivation until a sufficient amount of biomass is present in the container, or providing of a substance with anaerobic microorganisms, particularly cultivated the anaerobic cultivation of microorganisms comprising the steps of: providing an aqueous solution having a pH value of 4.5 to 7.5 in a container, adding a substrate in a first substrate dosage to the aqueous solution, adding further elements to the aqueous solution, adding an inoculant with microorganisms to the aqueous solution, wherein an initial product is provided by the abovementioned steps, and wherein, susbsequently, the following steps are performed: hermetically sealing the container, varying a temperature of the initial product or the intermediate products developing therefrom in a range from 40 to 80° C., wherein, after having added the substrate in the first substrate dosage, the following steps are performed for monitoring the cultivation: taking a reference liquid sample and determining a first concentration of organic substance in the reference liquid sample, taking another liquid sample and determining another concentration of organic substance in the further liquid sample after the expiration of the first waiting time, if the further concentration of organic substance is smaller than 10 percent of the first concentration of organic substance, adding substrate in another substrate dosage, repeating the abovementioned steps for monitoring the cultivation until a sufficient amount of biomass is present in the container. wherein the substance is subjected to the following steps for washing: centrifuging the substance for producing wet biomass. adding an isotonic solution to the wet biomass for producing a washed substance, wherein the steps for washing are repeated a plurality of times, if required, to thereby provide the preparation for cleaning radioactive liquids and surfaces, adding a substrate into the reactor, adding elements selected from the group of K, Ca, P, S, N, Zn, Co, Mn, Cl, Cu, Mo, Ni, Se, B, Fe, wherein, by the abovementioned steps, a working medium is provided, and wherein, further, the following step is performed: removing cleaned radioactive liquid from the reactor.

19. The method according to claim 18, wherein a selection from the group of K, Ca, P, S, N, Zn, Co, Mn, Cl, Cu, Mo, Ni, Se, B, Fe of added elements is depleted of one or more elements which are to be understood to be biochemical equivalents of the elements on which the radioactivity of the radioactive liquid is based.

20. The method according to claim 18, wherein one or more liquid samples are taken from the reactor and tested for their radioactivity, and in that, when a maximum value of the radioactivity is fallen below, the step of removing cleaned radioactive liquid from the reactor is performed.

21. The method according to claim 18, wherein the step of removing cleaned radioactive liquid from the reactor is performed after the expiration of a predetermined time.

22-32. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0077] The invention will now be explained by way of example with reference to the accompanying drawings with the aid of particularly preferred embodiments.

[0078] FIG. 1 shows a diagram for illustrating a method for the aerobic cultivation of microorganisms;

[0079] FIG. 2 shows a diagram for illustrating a method for the anaerobic cultivation of microorganisms;

[0080] FIG. 3 shows a diagram for illustrating of a method for cleaning radioactive liquids;

[0081] FIG. 4 shows a flow diagram for explaining a method for cleaning radioactive liquids.

DETAILED DESCRIPTION OF THE INVENTION

[0082] FIG. 1 shows a diagram for illustrating a method for the aerobic cultivation of microorganisms. For the aerobic cultivation von microorganisms, an aqueous solution 10 preferably having a pH value of 5.5 to 9.0 is provided in a container 12. The aqueous solution 10 is based on deionised water. To the aqueous solution 10, a substrate 14, particularly glucose is added. In addition, further elements are added, namely microelements and/or macroelements, the microelements being selected from the group of Mn, Mo, Zn, Cu, Co, Ni, Cl, Br, and the macroelements being selected from the group of C, H, O, N, S, K, Ca, P, Mg, Fe. Likewise, an inoculant 18 forming the basis of the biomass 20 to be cultivated is added. Outside of the container 12, a compressor 32 is provided which can introduce air into a jet nebuliser 36 through a pipe 34. The air is transported to the bottom of the container 12 so that it can be directly applied to the biomass 20 mainly present on the bottom of the container 12 there. Furthermore, a heating device 38 is disposed outside of the container 12. The heating device 38 is connected to a thermocouple 42 via a temperature controller 40 so that the temperature of the substances present in the container 12 can be controlled and/or regulated. Likewise, biomass collectors 44 are provided by means of which biomass 20 can be collected from the container 12.

[0083] FIG. 2 shows a diagram for illustrating a method for the anaerobic cultivation of microorganisms. In the container 12′ for the anaerobic cultivation of microorganisms, again, an aqueous solution 10′ is contained, however, preferably having a pH value of 4.5 to 7.5. To the aqueous solution 10′, again, a substrate 14′, preferably glucose, other elements 16′, namely microelements and macroelements as indicated above, and an inoculant 18′ are added. Here as well, the inoculant 18′ is the initial substance for the biomass 20′ cultivated therefrom. Also, again a heating device 38′ is provided which is connected to a thermocouple 42′ via a temperature controller 40′, the heating device 38′ and the temperature controller 40′ being disposed outside of the container 12′ while the thermocouple 42′ is disposed in the container 12′ and particularly in the substances present in the container 12′ so that again the temperature of the substances can be controlled and/or regulated. The container 12′ further contains one or more biomass collectors 44′ for collecting biomass 20′. The container 12′ is hermetically closable by means of a closure 46′, particularly to prevent air from entering. In order to render the discharge of gases released within the container 12′ possible, a siphon-like water trap 48′ is provided on the upper side of the container 12′.

[0084] The preparation which is ultimately to be used for cleaning radioactive liquids and which is obtained on the basis of the described cultivation of microorganisms contains various groups of aerobic and anaerobic microorganisms, among them extremophiles which can exist under extreme conditions, namely at low and high temperatures (psychrophilies and thermophilies), in a high salt content (hallophilies) as well as at high radiation levels (radioresistant microorganisms).

[0085] The preparation of the preparation takes place by the non-sterile cultivation of various microbial primal associations originating from natural and technogenic sources by varying the growth conditions with the aim of obtaining associations characterised by a mutually beneficial coexistence. In addition, the climatic conditions of the intended place of use as well as the background composition of the primal microorganisms are taken into account in the preparation of the preparation. During the cultivation, apart from biogenic compounds, also such compounds which are toxic for microorganisms - in doses from harmless to semi-lethal - are contained in the solutions for the cultivation of the preparation. In addition, the solutions may contain the following substances: salts of heavy metals, petroleum products (among them polyaromatic hydrocarbons), surfactants, carbohydrates, protein, fats, etc. In an aggressive environment, non-surviving microorganisms of the preparation are a source for additional protection and nutrition for the surviving community.

[0086] A cultivation method according to the invention as the basis for the production of the preparation for cleaning radioactive waste can also be described as follows.

[0087] A first process step is the extraction of liquid (without biomass) on the occasion of the first addition of 1 ml substrate as well as the subsequent centrifugation at 14500 rpm for 3 minutes at ambient temperature. A content analysis is performed on the organic substance.

[0088] A second process step is the extraction of liquid (without biomass) 24 hours after the addition of 1 ml substrate including the subsequent centrifugation at 14500 rpm for 3 minutes at ambient temperature. A content analysis is performed on the organic substance.

[0089] Provided that, in the third process step, it is found that 90% of the organic substance was consumed, the next substrate dosage should be added within the course of 14 days (aerobic) or 50 days (anaerobic), regular content analyses of the organic substance and of the biogenic elements having to be carried out. In case there was no consumption of 90 percent the second process step is repeated.

[0090] Otherwise, the collection of 400 ml of biomass concentrate from a bioreactor as well as a centrifugation of the concentrate at 4000 rpm at 3 to 8° C. will be effected in the fourth process step (production stage). The excess of the centrifugation is returned into the bioreactor. The mass of moist biomass is determined, likewise the moisture content of the biomass.

[0091] In a fifth process step, the adapted biomass is ready for use if the mass of the centrifuged wet biomass is more than 50 grams per litre. Otherwise, the third process step and the following are repeated.

[0092] When the microbial association which, in particular, can be obtained by the described cultivation methods is thus ready for use compounds impeding the intended process are extracted from the biomass. The biomass is separated from the solution by centrifugation. If required, the biomass cultivated in various modes is mixed and washed three times with the isotonic solution on the basis of deionised water such as, for example, 0.1 to 0.9% NaCl solution in the ratio of 1:10 to 1:30. Then, it is centrifuged. The essence of this method is that the washing of biomass extracts compounds impeding the intended process of processing liquid radioactive waste.

[0093] A washing method within the scope of the production of the preparation for cleaning radioactive waste can also be described as follows.

[0094] From the containers in which the biomass is cultivated in the aerobic and anaerobic mode, the culture liquids are extracted and mixed in the ratio of 1:5 to 5:1 as well as centrifuged at 4000 revolutions per minute at a temperature of 3 to 8° C. for 8 to 12 minutes. The excess water is analysed for its elementary composition and introduced into a container for the recultivation of biomass.

[0095] The obtained wet biomass is added into isotonic solution in the ratio of biomass to solution of 1:4 bis 1:10 and thoroughly agitated for 5 to 10 minutes to avoid or eliminate a formation of clumps of the biomass.

[0096] The obtained solution is centrifuged at 4000 rpm at 3 to8° C. for 8 to 12 minutes. The excess water is discharged into the sewage system. The process is repeated, for example, three times.

[0097] In order to verify that the undesired elements were completely removed from the biomass, mass spectrometric analyses for the presence of elements are carried out on the initial excess and the third washing solution.

[0098] The washed moist biomass constituting the basis of the preparation for cleaning radioactive liquids is used for the processing of liquid radioactive waste either in a free form or in a special container or cartridge.

[0099] Special cartridges are hermetically closed containers made of a water-permeable non-woven fabric which let no microorganisms escape to the outside.

[0100] There is also the option to have the preparation prepared in the form of a dry powder, namely by lyophilisation. The approach for obtaining a dry powder including about 90% viable microorganisms is as follows.

[0101] Into the moist, washed, (after centrifuging) paste-like biomass, a cryoprotector is introduced, e.g. a water solution of dextran polysaccharide - 40% polyglucan solution in the ratio of 2.5% polyglucin in the finished paste and 2.5% glycerin (for 70 I of paste - 4.37 I of the 40 percent polyglucan solution and 1.75 I of glycerin). It is mixed for 10 minutes.

[0102] The finished mixture is frozen at -70° C.

[0103] The frozen mixture is subjected to lyophilic dehydration until a powder having a residual moisture of not more than 1 - 3% is formed.

[0104] This powder is tightly sealed in polyethylene bags under vacuum.

[0105] The properties of the preparation in the dry form remain unchanged for 3 years.

[0106] Therefore, the finished preparation consists of several thousands of microorganisms of various species adapted to life in hash conditions. Part of the microorganisms is capable of developing in aerobic and anaerobic conditions at a temperature of 20 to 80° C.

[0107] The cultivation and further processing of the microorganisms for the preparation does not require sterile conditions, expensive devices and reagents which renders keeping the original costs of the production of the preparation low possible.

[0108] FIG. 3 shows a diagram for illustrating a method for cleaning radioactive liquids. A primary container 50 is provided in which radioactive liquid 24 to be cleaned is prepared. The radioactive liquid 24 to be cleaned is introduced into the container 50 through an opening 52 provided on the upper side of the primary container 50, along with, if required, deionised water 54 and macro- and microelements 56 as listed in detail above. The mixture or solution present in the primary container 50 is supplied to an analysis unit 58, it being decided based on the results of the analysis whether the mixture or solution is to be changed in its composition, for example to be diluted. As soon as the content of the primary container 50 has the desired properties, the content is completely or partly removed and supplied to a conveyor system 60. This conveyor system 60 conveys the content, i.e. the radioactive liquid 24 to be cleaned, into the reactor 22. Apart from the radioactive liquid 24 to be cleaned, a preparation 28 which was, particularly, obtained on the basis of the cultivation described in connection with FIGS. 1 and 2, as well as again a substrate 30, particularly glucose, are supplied to the reactor 22. Outside of the reactor 22, a heating device 62 is provided which is connected to a thermocouple 66 placed in the reactor 22 via a temperature controller 64 also disposed outside of the reactor 22. Thus, the temperature in the reactor 22 or of the substances present in the reactor 22 can be controlled and/or regulated. The reactor 22 is hermetically closable by a closure 68. In order to allow for gases released within the reactor 22 to be discharged, a siphon-like water trap 70 is provided on the upper side of the reactor 22. For the purpose of the air supply, a compressor 72 connected to a jet nebuliser 76 within the container via a pipe 74 is disposed outside of the reactor 22. Furthermore, an agitator 78 by means of which the substances in the reactor 22 can be stirred is disposed in the reactor 22. The content of the reactor 22 can be supplied to an analysing unit 98. Essentially, the reactor 22 is capable of processing aerobic and anaerobic microorganisms to clean the added radioactive liquid 24 based on them in this way. In case of a strictly anaerobic biomass, however, the means for supplying air, i.e. the compressor 72, the pipe 74, and the jet nebuliser 76, can, in principle, be omitted. The reactor 22 further comprises a biomass discharge system 80 through which the biomass 28 is suppliable to a filter press 82. In this filter press 82, the biomass 28 can be mechanically dehydrated, whereupon it is suppliable to a heating plate 84 to be incinerated there. Depending on whether the ash is below a radioactivity threshold, it can be supplied to a disposal 86 as low risk waste, or it is disposed of in a final disposal site 88 for the final storage of radioactive waste. The liquid emerging from the filter press 22 is supplied to an analysing unit 90. In this analysing unit, it will be determined whether the liquid is below a radioactivity threshold. If this is the case the liquid can be supplied to a waste water container 92 in which cleaned radioactive liquid 26, i.e. particularly no longer radioactive liquid or modestly radioactive liquid, from the filter press 82 is collected. However, if the radioactivity of the liquid from the filter press 82 exceeds a predetermined radioactivity threshold, it is returned to one of the preceding process stages, i.e., in particular, supplied to the primary container 50 or the reactor 22. The waste water container 92 is also supplied with the liquid freed from radioactivity from the reactor 22, namely through the reactor’s on-site discharge system 94 for cleaned liquid as well as a coarse cleaning filter 96.

[0109] FIG. 4 shows a flow diagram for explaining a method for cleaning radioactive liquids. In step S01, radioactive liquid is made available in a primary container. The content of the primary container is analysed in step S02, a change of the content depending on the results of the analysis still being possible, for example by the targeted addition of macroelements and/or microelements and/or of additional deionised water for dilution. In step S03, the radioactive liquid is filled into the reactor. In step S04, the preparation for cleaning is supplied, and in step S05 the substrate, i.e. particularly glucose. Subsequently, according to step S06, there is a waiting time of a period of time t. In step S07, a liquid sample is taken and analysed for radioactivity. If, in step S08, it is determined that the radioactivity (RA) has not yet fallen below a maximum radioactivity (RAmax), the course of the process will be returned to step S06, and there is another specified waiting time. However, when the radioactivity has fallen below a maximum radioactivity (RAmax), the liquid can be removed from the reactor. It is filtered in step S14, and filled into a container for non-radioactive waste water in step S15. The biomass is also removed from the reactor and dehydrated in step S09. The dehydrated biomass is incinerated in step S12 and permanently stored in step S13. Instead of a final storage, it can also be disposed of as low risk waste in case of a sufficiently low or no longer detectable radioactivity of the incinerated biomass. The liquid resulting from the dehydration performed in step S09 is analysed for its radioactivity in step S10. In step S11, it is tested whether the radioactivity (RA) is smaller than a maximum radioactivity (RAmax). If this is the case the liquid can be filled into a container for non-radioactive waste water according to step S15. If the radioactivity (RA) is not lower than a maximum radioactivity (RAmax) the liquid is returned to the primary container according to step S17 or to the reactor according to step S16.

[0110] For cleaning purposes, the radioactive waste is thus introduced into a special reactor enabling a thermostat function for its content as well as ventilation and/or stirring with air and/or an agitator. In the reactor, there is also the preparation, a set of macro- and microelements and a substrate for the growth of the culture. The process takes place at a temperature of 20 to 80° C. In case of aerobic cultures, flowing air from an external compressor is supplied through a tube having a weight and a nebuliser at the outlet at a rate of 1.5 bis 3.0 I/min per one litre of the liquid radioactive waste for ventilation. The duration of the ventilation and/or stirring varies from continuously to periodically depending on the processing objective. For example, the duration may be 20 s per day. In the process, the preparation should be stirrable from the bottom to the surface; however, a leakage of the biomass on the upper container walls (not covered by liquid) in the course of the method is to be avoided. The consumption of the preparation varies from 1 bis 35 g moist biomass (moisture 93 - 99%) or 0.01 - 2.45 g lyophilised powder per one litre of the liquid radioactive waste. As the substrate, for example, highly pure glucose is used which is added in an amount of 0.5 to 5 g per one litre of the liquid radioactive waste per day. As the biogenic elements, K, Ca, P, S, N, Zn, Co, Mn, Cl, Cu, Mo, Ni, Se, B, Fe are introduced. However, to achieve the conditions of an accelerated biosorption, particularly in case of anaerobic cultures, or to reduce the activity the solution, particularly in case of aerobic cultures, one or some elements should be missing in the medium to be processed if they are stoichiometric equivalents of the radionuclide to be processed which is used for growth by the microorganism cells.

[0111] Depending on the processing objectives, the liquid radioactive waste is converted into solid radioactive waste with a multiple reduction of volume, or the activity of the liquid radioactive waste is directly reduced.

[0112] The liquid radioactive waste is first supplied to a preparation container or primary container. Samples are taken to carry out necessary analyses, e.g. with the following methods: [0113] mass spectrometry (identification of stable and radioactive elements); [0114] ion chromatography by means of a conductometric detector; [0115] potentiometry.

[0116] The effect of the preparation was, in particular, tested under the following conditions: [0117] radioactivity of the solution lower than 2.Math.10.sup.2 kBq/l; [0118] overall salt content lower than 100 g/l; [0119] pH value of the medium from 5 to 9.

[0120] After having performed the examinations, it is therefore recommended to dilute the liquid radioactive waste with deionised water when required. Then, macro- and microelements are introduced into the primary container when required.

[0121] It is important to emphasise that the liquid radioactive waste should not contain any stable isotopes of the radionuclides to be disposed of so as to be capable of successfully reducing the radioactivity. For growth, the microorganisms will, first of all, absorb the stable isotopes of the radionuclides to be disposed of. From the mixture .sup.133Cs and .sup.137Cs, e.g., the preparation will first process the stable isotope .sup.133Cs. Consequently, the radioactivity of the liquid radioactive waste will not change in the process.

[0122] The prepared liquid radioactive waste is supplied into the reactor via the conveyor system.

[0123] Then, the preparation and the substrate for the growth of the microbiological cultures are added into the reactor. While the ventilation and/or stirring are deactivated, the reactor lid is tightly closed. The lid is equipped with a liquid seal filled with deionised water and discharging excess gas from the reactor when required. The temperature in the reactor is maintained at the target level by means of a heating element and a temperature control encoder. The temperature of the medium in the reactor is adjusted with the aid of a thermocouple. The ventilation takes place with oxygen from the ambient air which is supplied via the compressor and the jet nebuliser. The stirring is carried out by a built-in propeller. Regularly, a sample is taken from the upper liquid layer to determine the radioactivity. When it is the objective to rapidly store the radionuclides in the microorganisms for further final storage the maximum biosorption is reached within 1 to 7 days. If it is the objective to reduce the radioactivity of the solution while no final storage of the radioactive substances is intended it is required to maintain the fast growth of the microorganisms until the radioactivity is reduced to the background or target level.

[0124] When the objective of cleaning the water solution from the radionuclides is reached the liquid cleared of the radionuclides flows into the containers for the non-radioactive waste water via the discharge system and a coarse filter, e.g. a sand filter, and the spent biomass of the preparation is transferred onto the filter press by the biomass-discharge system. If a cartridge is used the cartridge including the spent biomass is removed from the water, then mechanically pressed out above the water surface according to the tea bag principle, dried in air, and then opened to place the content (spent biomass) on the heating plate and to bypass the filter press.

[0125] If the preparation is used in a loose form (without a cartridge) the spent biomass having a moisture of about 93 - 99% is mechanically dehydrated in the filter press to the largest possible extent and then placed on the heating plate for a slight incineration in air at a temperature of not more than 250° C. In the process, the liquid separated from the biomass in the filter press is examined for radioactivity. If the radioactivity of the filtrate does not exceed the target values the liquid is also discharged into the containers for the non-radioactive waste water. Otherwise, the liquid flows back into the reactor or into the primary container for the preparation of the liquid radioactive waste to be processed with the next batch of the liquid radioactive waste. If a reduction of the radioactivity below specific target values is not required or if no further batch of liquid radioactive waste is in the queue for cleaning the radioactive filtrate the volume of which does not exceed the volume of the spent moist biomass may be evaporated onto the heating plate for the further final storage of the residual salts.

[0126] When the biosorption of the radionuclides is applied the generated ash including the radionuclides stored in it is forwarded for final storage. In case of a reduction of the radioactivity, the ash poses no risk to humans, plants, and animals and can be disposed of according to traditional methods.

[0127] When the objective of clearing the water solution of the radionuclides by sorption was not reached in the first application of the preparation it is required to replace the spent preparation by new preparation. Here, the liquid radioactive waste and the spent biomass are processed as described above. The method of biosorption should be repeated until the radioactivity of the solution is reduced to the background or target level.

[0128] In the final stage of the processing of the liquid radioactive waste by means of the method of biosorption by means of the preparation, low risk “technical” water and completely dry ash of the microorganisms including the radioactive elements stored in it are generated. In this way, a multiple reduction of the amount of waste for final storage is achieved. In case of a successful transformation of the radionuclides into stable elements, no final storage of the waste is required.

[0129] The association of microbes existing on the edge of survival incorporates radionuclides into the cells. In the process, the microorganisms grow by lysis of some cells and discharge of remaining amounts of deficiency macroelements into the water medium. In the biological systems, the atomic transformations take place in nanoscale spaces of the microorganism cells. For the protons, the nanoscale spaces of the growing biological cells represent potential wells having dynamically changing walls creating coherent correlated states of the quantum particles. The protons existing in these states are capable of a reaction resulting in the formation of elements required for the further performance of biochemical processes in the microorganisms. Therefore, the active division of the cells including the radionuclides in the nanoscale spaces results in the reduction of the radioactivity under formation of the stable elements from the radionuclides.

[0130] In the present context, the phenomenon of the transmutation of atomic nuclei by nucleosynthesis may play a role. For nucleosynthesis, a number of requirements has to be fulfilled. One of them is associated with the necessity of incorporating the synthesising isotope in the metabolism as fast as possible including the associated fixation as a stable nucleus (stable atom). It is obvious that the biochemical processes supporting storage simultaneously promote the transmutation of atomic nuclei. During the growth of microbiological cultures, the reproduction of DNA molecules and some other macromolecules, their orientation, and the formation of the primary and secondary structures take place. In the area of the structural adaptation, a continuous process of the formation and modification of microinhomogenities with a characteristic magnitude of the same order takes place which is required for the “elimination” of the Coulomb barrier in the transmutation of atomic nuclei. If the nutrient medium for the microbiological culture does not contain an isotope of the element required for the growth of the culture, but the other isotopes which may constitute the isotope required for the growth as result of the transmutation of atomic nuclei this isotope is, upon formation as the result of a reaction, immediately absorbed by and fixed in the microbiological culture in optimum micro activities. Therefore, there is the possibility to utilise the transformation of the radioactive isotopes absorbed by the bacteria culture into stable isotopes of other chemical elements. In this case, this does not refer to a comprehensive use of microbiological systems in the first stages of the processing of spent fuel elements and highly active waste.

[0131] In the following, some examples for illustrating the invention are provided:

[0132] Example 1: As a model for waste water including heavy metals, deionised water in a volume of 75 ml with K.sub.2Cr.sub.2O.sub.7 dissolved therein in a concentration of 0.1 g/l and with an overall salt content of about 100 g/l was used. Introduced into the reactor were: A set of macro- and microelements with the exception of biochemical chromium equivalents, then moist paste-like preparation in an amount of 2.21 g as well as a substrate in the ratio of 5 to 6 g organic substance per one litre of the mixture. The experiment was predominantly carried out under microaerophilic conditions at a temperature of 55 to 80° C. In the course of the experiment, the pH value of the medium changed in the range of 6.9 to 7.9. The consumption level of the organic substance and the relevant macro- and microelements were monitored. Within a maximum of 7 days, the initially coloured solution became completely colourless. Spectrophotometric examinations still revealed traces of chromium in the solution.

[0133] Example 2: Here, the approach was like in Example 1 with the exception that the compound K.sub.2Cr.sub.2O.sub.7 was used in a concentration of 10 g/l. In this case, the solution became colourless within 50 days of the experiment. Spectrophotometric examinations again revealed traces of chromium in the solution. The preparation had a bluish tint.

[0134] Example 3: As a model for liquid radioactive waste, deionised water in a volume of 75 ml with radioactive caesium having an activity of 180 kBq/l dissolved in the water was used. Introduced into the reactor were: A set of macro- and microelements with the exception of biochemical caesium-equivalents, then moist paste-like preparation in an amount of 2.5 g as well as a substrate in the ratio of 3 to 4 g organic substance per one litre of the mixture. The experiment was predominantly carried out under microaerophilic conditions at a temperature of 55 to 65° C. In the course of the experiment, the pH value of the medium changed in the range from 5.4 to 7.5. Within 20 days, the activity of the liquid was reduced down to 20 kBq/l.

[0135] Example 4: As a model for liquid radioactive waste, deionised water in a volume of 750 ml with the compound CsNO.sub.3 in a concentration of 0.5 g/l dissolved in the water was used. Introduced into the reactor were: A set of macro- and microelements with the exception of biochemical caesium-equivalents, then moist paste-like preparation in an amount of 9.55 g as well as a substrate in the ratio of 0.5 bis 1 g organic substance per one litre of the mixture. The experiment was predominantly carried out under aerobic conditions at a temperature of 20 to 28° C. In the course of the experiment, the pH value of the medium changed in the range from 6.1 to 7.9. The consumption level of the organic substance and the relevant macro- and microelements were monitored. Within a maximum of 7 days, mass spectrometric analyses revealed a transition from Cs into the biomass. The caesium content in the biomass was up to 300 mg/g of the completely dry biomass.

[0136] Example 5: As a model for liquid radioactive waste, deionised water in a volume of 75 ml with the radioactive caesium-compound CsNO.sub.3 dissolved in the water was used which guarantees a caesium content at a level of 5.Math.10.sup.4 Bq. Introduced into the reactor were: A set of macro- and microelements with the exception of biochemical caesium equivalents, then moist paste-like preparation in an amount of 0.9 g. No substrate was introduced into the bioreactors. The experiment was predominantly carried out under aerobic conditions at a temperature of 20 to 25° C. In the course of the experiment, the pH value of the medium changed in the range from 6.1 to 7.2. The biomass was removed from the reactor every 1 to 3 days. Radiospectroscopic examinations of the biomass revealed a caesium content in the moist biomass of up to 17 kBq per one gram of the completely dry biomass.

[0137] Example 6: As a model for liquid radioactive waste, deionised water in a volume of 700 ml with a compound of stable caesium CsNO.sub.3 in a concentration of 0.12 g/l dissolved in the water was used. The preparation was introduced into the reactor so that the bioreactor contained 10 g of the moist biomass and a set of macro- and microelements with the exception of biochemical caesium equivalents as well as a substrate in the ratio of 2 to 3 g organic substance per one litre of the mixture. The experiment was predominantly carried out under microaerophilic conditions at a temperature of 35 to 45° C. The best result was already achieved after 8 days of the experiment. An analysis of the content of the bioreactor by means of atomic emission spectrometry with an inductively coupled plasma revealed that the caesium content was reduced by 55%. In the bioreactors, barium was detected which may indicate a transmutation of atomic nuclei.

[0138] Example 7: As a model for liquid radioactive waste, deionised water in a volume of 750 ml with the radioactive caesium compound CsNO.sub.3 dissolved in the water was used which guarantees a caesium content on a level of 10.sup.4 Bq. Introduced into the reactor were: A set of macro- and microelements with the exception of biochemical caesium equivalents, then moist paste-like preparation in an amount of 9.05 g as well as a substrate in the ratio of 0.5 bis 1 g organic substance per one litre of the mixture. The experiment was carried out under aerobic conditions at a temperature of 20 to 28° C. In the course of the experiment the pH value of the medium changed in the range from 6.5 to 8.1. The consumption level of the organic substance and the relevant macro- and microelements were monitored. Within a maximum of 15 days, radiospectroscopic examinations revealed an average reduction of the activity of the content of the bioreactor by 23%.

[0139] If radionuclides from water solutions are to be rapidly concentrated the preparation seems to be a universal biosorbent which is easy to dispose of and which is capable of extracting all substances in arbitrary quantity ratios from the liquid radioactive waste. In case of a rational change of the element composition in the medium and during the growth of the microorganisms, the preparation is capable of transforming predetermined elements and thus transform the radioactive elements from the liquid radioactive waste into non-radioactive elements.

[0140] In the biological processing of liquid radioactive waste under application of the preparation, no extreme temperatures or pressures are required so that the method requires a low energy intensity. Furthermore, the application of the preparation does not require the introduction of hazardous chemical reagents which excludes the risk of a secondary contamination. The features described above guarantee utmost simplicity and operational safety of the procedural facility.

[0141] The features of the invention disclosed in the above description, in the drawings as well as in the claims may be important for the realisation of the invention both individually and in any combination.

TABLE-US-00001 List of numerals 10 Aqueous solution 10′ Aqueous solution 12 Container 12′ Container 14 Substrate 14′ Substrate 16 Other elements 16′ Other elements 18 Inoculant 18′ Inoculant 20 Biomass 20′ Biomass 22 Reactor 24 Radioactive liquid 26 Radioactive liquid 28 Biomass 30 Substrate 32 Compressor 34 Pipe 36 Jet nebuliser 38 Heating device 38′ Heating device 40 Temperature controller 40′ Temperature controller 42 Thermocouple 42′ Thermocouple 44 Biomass collector 44′ Biomass collector 46′ Closure 48′ Water trap 50 Primary container 52
Opening
58 Analysis unit 60 Conveyor system 62 Heating device 64 Temperature controller 66 Thermocouple 68 Closure 70 Water trap 72 Compressor 74 Pipe 76 Jet nebuliser 78 Agitator 80 Biomass discharge system 82 Filter press 84 Heating plate 86 Disposal 88 Final disposal site 90 Analysing unit 92 Waste water container 94 Discharge system 96 Coarse cleaning filter 98 Analysing unit