DECOUPLED MULTI-TROPHIC PRODUCTION FACILITY WITH DISTILLATION UNIT

Abstract

A facility for growing vegetation, the facility comprising at least one container for taking aquatic animals and/or aquatic organisms (2), at least one hydroponic part (13), at least one device for water and/or substance circulation (17) whereby the facility further comprises at least one unit (16) for distillation.

Claims

1. A facility for growing vegetation, the facility comprising: at least one container for taking aquatic animals and/or aquatic organisms; at least one hydroponic part; at least one device for water and/or substance circulation; and at least one unit for distillation.

2. The facility of claim 1 wherein the container is a fish tank.

3. The facility of claim 1, further comprising at least one mechanical filter unit for filtering the medium.

4. The facility of claim 1 further comprising at least one unit for bio filtration of the medium.

5. The facility of claim 1, wherein the at least one hydroponic part comprises a deep water culture (DWC)-system.

6. The facility of claim 1 wherein the at least one hydroponic part comprises a nutrient film technique (NFT)-system and/or grow bed system.

7. The facility of claim 1 wherein the facility is configured to provide for at least one of controlling temperature, controlling environmental parameters, controlling oxygen level, controlling pH-value, controlling nitrogen compounds, controlling alkalinity, controlling nutrients, controlling macronutrients, and controlling micronutrients.

8. The facility of claim 1 further comprising a photovoltaic system.

9. A method for operating the facility of claim 1, the method comprising: distilling the medium with the at least one distillation unit to produce hydroponic solution and demineralized water; circulating the hydroponic solution from the at least one distillation unit to the at least one hydroponic part; and circulating the demineralized water from the at least one distillation unit to the at least one container.

10. The facility of claim 1 further comprising a biogas system.

11. The facility of claim 1 wherein the at least one distillation unit is configured to desalinate sea or brackish water.

12. A facility for growing vegetation, the facility comprising: at least one container for taking aquatic animals and/or aquatic organisms; at least one hydroponic system; at least one device for circulation of a medium; and at least one unit for distillation; wherein the at least one unit for distillation is positioned within the facility such that the at least one unit for distillation processes the medium being exchanged between the at least one container and the at least one hydroponic system by distilling the medium, thereby separating demineralized water from the medium and a hydroponic nutrient solution from the medium; wherein the facility is configured to direct the demineralized water separated by the at least one unit for distillation towards the at least one multi-trophic container; wherein the facility is configured to direct the hydroponic nutrient solution separated by the at least one unit for distillation towards the at least one hydroponic system.

13. The facility of claim 12 wherein the at least one container is a fish tank.

14. The facility of claim 14 further comprising at least one mechanical filter unit for filtering the medium.

15. The facility of claim 14 further comprising a biofilter unit positioned to filter the demineralized water prior to the demineralized water reaching the at least one multi-trophic container.

16. The facility of claim 15 wherein the at least one hydroponic part comprises a deep water culture (DWC) system.

17. The facility of claim 15 wherein the at least one hydroponic part comprises a nutrient film technique (NFT) system.

18. The facility of claim 15 wherein the at least on hydroponic part comprises a grow bed system.

19. The facility of claim 15 further comprising a gas exchange unit for processing the medium prior to the medium reaching the container.

20. A method for operating the facility of claim 12, the method comprising: distilling the medium with the at least one distillation unit to produce the hydroponic solution and the demineralized water; circulating the hydroponic solution from the at least one distillation unit to the at least one hydroponic part; and circulating the demineralized water from the at least one distillation unit to the at least one container.

Description

EXAMPLE OF CARRYING OUT THE INVENTION

[0173] The system and method according to the invention is described in more detail; however the invention is not restricted to this detail, which shows in

[0174] FIG. 1: a water flow scheme of the multi-loop aquaponics system.

[0175] The facility 1 according to the invention shows a scheme of the multi-loop aquaponics system comprising four part-systems which are decoupled.

[0176] The facility according to the invention comprises accordingly multi-trophic units 2, 4, 6, 7 as well as hydroponic units 13, 12, 14.

[0177] The facility also comprises a distillation unit 16 and/or a bio reactor unit 8, 9, 10, 11. The use of recirculating aquaculture systems is an embodiment of the multi-trophic part of the facility.

[0178] A multi-trophic part of the facility comprises a container 2.

[0179] This multi-trophic system as shown in FIG. 1 comprises besides the container 2 additional units, such as a bio-filter unit 6, a gas exchange unit 5, a mechanical filter unit 4. These additional units are arranged outside of the container 2.

[0180] The multi-trophic container 2 is designed to contain the fish. The container has one or more connectors to a medium discharge line, e.g. a water discharge line, which conducts the medium into at least one sedimentation tank or chamber (not shown). This sedimentation device may be used as pre-filtration system as well as pump sumps.

[0181] The total medium flow is split into two independent loops. The first loop can be used for conducting the medium, e.g. water, to the plant facility, i.e. to the hydroponic part, according to the invention. The second independent loop returns water back from the hydroponic part of the facility to the multi-trophic container 2 containing the fish, i.e. fish tank 3.

[0182] The facility comprises a unit for mechanical filtration 4 of the medium of the recirculating aquaculture system. In order to maintain good medium quality and to prevent the system from decaying, it is necessary to remove rests of feed given to the fish and the effluents of the fish, e.g. excrements. This is processed by the mechanical filtration unit 4.

[0183] The mechanical filtration unit 4 is arranged directly following the multi-trophic container 2, i.e. the fish tank 3, and ahead of a bio filter unit 6, according to this example of carrying out the invention.

[0184] The mechanical filtration unit 4 separates the solid parts of the medium, e.g. feed rests, excrements, from the rest of the medium, i.e. from the liquid part of the medium.

[0185] From the mechanical filtration unit 4 the liquid part of the medium is being conducted to the sump unit 7 whereas the solid parts of the medium are conducted to a bio reactor unit 8, if provided, each for further processing. In case a bio reactor is not provided the solid parts are also conducted to the sump unit.

[0186] The sequence order of the sump unit 7 or the bio filtration unit 5 may be as desired.

[0187] The sump unit 7 receives at least most of the liquid part of the medium for further processing. The sump unit 7 is designed for a further refinement process, e.g. for further separation of the nutrient components. At least most of the nutrient-enriched part of the liquid is further conducted to the hydroponics sump unit 12. This nutrient-enriched part is intended for further processing within the hydroponic part 13, 12, 14 of the entire facility 1.

[0188] The nutrient-poor liquid part of the medium which will be returned to the container 2 at the end of the processing steps and will be conducted from the sump unit 7 either entirely or partially to the bio filtration unit 6.

[0189] In case the bio filtration unit 6 follows directly the mechanical filtration unit 4 the liquid part of the medium mentioned will be conducted to the sump unit 7 of the multi-trophic part of the facility 1 and further processed in this sump unit 7 as described and then either fully or partially conducted to an optional gas exchange unit 5 or entirely conducted to the fish tank 3 back again.

[0190] The unit for bio filtration 6 aims at a removal ofamong othersammonia, dissolved organics and carbon dioxide. The ammonia being a toxic metabolite found in the excrements of the fish, is being converted into nitrite and/or nitrate.

[0191] After having removed all or a great part of the solids by the above mentioned mechanical filtration unit 4, the medium, e.g. water, is conducted through the bio filter unit 6 where the ammonia will be converted first to nitrite and then to nitrate.

[0192] The system according to the invention preferably comprises, hence, a unit for denitrification. The unit deals with the existing of nitrate in oxygenated waters; the nitrate (NH.sub.4.sup.+) can be biochemically transferred to nitrite (NH.sub.3) which again can be oxidized to nitrate once more. The denitrification unit is, hence, capable of denitrification, i.e. reducing nitrate, as well as of nitrification, i.e. oxidation of ammonia or ammonium to nitrite.

[0193] The nitrate received by this process is in addition an important nitrogen source for the plants. Since nitrite is also toxic to the fish it has to be ensured that the bacterial system in the bio filter facility works properly with the result that the ammonia is kept within non-toxic levels; the existence of ammonia cannot be deleted completely since the fish segregate permanently ammonia due to the excrements. This means, the bio filtering is an ongoing process.

[0194] According to FIG. 1 the RAS part of the invention comprises a (optional) gas exchange unit 5. The gas exchange unit 5 dissolves CO.sub.2 from the medium, e.g. water, and optimizes the level of oxygen. Oxygen is an important quality parameter for the growth of fish. The configuration of the gas exchange unit 5 depends on kind of fish, size of fish, feeding parameters, water temperature and so on.

[0195] After passing this optional gas exchange unit 5 the previously mentioned bio filtration unit 6 or sump unit 7 the nutrient-poor water is conducted back to the container 2 of the RAS loop.

[0196] The other main part of the system is the at least one hydroponic system 13 comprising at least one hydroponic sump unit 12 and at least one deep water culture unit 14 allowing plants to grow and suspend with the roots immersed in the nutrient solution.

[0197] The at least one hydroponic part 13, 12, 14 of the entire facility 1 of the invention comprises a container 14, which contains the substrates for the growth of the vegetation, e.g. the plants, andof coursethe plants themselves.

[0198] There exist various constructional approaches of these hydroponic parts of the facility possible.

[0199] One of these techniques refers to the deep water culture (hereinafter: DWC) also known as direct water culture, that works by suspending the plants' roots directly into a highly oxygenated nutrient solution.

[0200] Since hydroponics isas already mentioneda soil-less cultivation system, the nutrients for the plants are being deliveredamong othersby the fish food as fish waste, i.e. as excrements. The nutrients may be divided into macronutrients and micronutrients. Macronutrients as nitrogen N, phosphorus P, potassium K, calcium Ca, magnesium Mg and sulfur S are of at most importance for the plants.

[0201] Micronutrients such as iron Fe, copper Cu, boron B, zinc Zn etc. may be preferably added.

[0202] Since the nutrient in the system comes through the fish food as fish waste or rests of the food, the macro- and micro-nutrient concentration in the RAS loop is automatically consistently higher than in the hydroponic component in case no additional fertilizer inputs occur in the hydroponic part. On the other hand, as already mentioned, the converse situation should be achieved since the plants in the hydroponic loop need the supply of the macro- and micro-nutrient concentration.

[0203] On the other hand, fish needs nutrient-poor medium. Just conducting the nutrient-enriched medium of the RAS part to the hydroponic part and filling the RAS part with fresh medium would lead the entire system ad absurdum because no medium, e.g. water, could be saved at all.

[0204] In addition, it is to be mentioned that addition of artificial fertilizers may on the base of further costs raise as well as of raise of the ecological footprint the hydroponic nutrient content, however, it would not solve the problem of the high nitrate values in the RAS.

[0205] The applicant has surprisingly found that such an obstacle of additional fertilization can be overcome by implementing a distillation process. Thus, it is an essential feature of one embodiment of the invention, to provide a unit for distillation 16.

[0206] Accordingly part of the system is the providing of a unit (facility) for distillation 16. Water from the hydroponics sump 12 is being concentrated in the distillation plant 16 resulting in two separated flows, namely transporting back demineralized water to the RAS having nutrient-poor conditions for the fish and concentrated nutrient solution, i.e. increased nutrient concentration, flowing back to the hydroponic loop 13.

[0207] Distillation in this context is capable of increasing the nutrient concentration within the hydroponic loop 13, 12, 14 while ensuring preferable nutrient-poor conditions for the fish. In addition, water usage can also be minimized. The distillation unit overcomes water and nutrient discharges. Distillation technology can be used to balance nutrient concentrations.

[0208] As already mentioned above with regard to the multi-trophic part 2, 4, 6, 7 of the facility 1 the hydroponic sump unit 12 receives medium, e.g. water, from the sump unit 7 of the multi-trophic part of the facility. The hydroponic sump unit 12 itself conducts at least a great part of the medium received to the distillation unit 16.

[0209] Water from the hydroponics sump is being concentrated in the distillation unit resulting in two separated flows, namely a demineralized water to the RAS on the one hand and a concentrated nutrient solution (i.e. brine) flowing back to the hydroponic loop on the other hand.

[0210] The distillation unit 16 is, therefore, capable of concentrating the hydroponic nutrient solution and of directing demineralized water to the RAS part of the system back again. The nutrient solution which is achieved by running this process in the units described contains the nutrient concentrate. This concentrate usually does not consist of particulate nutrients, i.e. solid nutrients but of dissolved nutrients.

[0211] A further advantage of the facility is that the hydroponic and RAS nutrient concentrations are directly regulated. The treated sludge, i.e. waste, is further concentrated to increase the concentration in the hydroponics and to increase water quality in the RAS.

[0212] Additionally to the proportioning of the nutrient concentrations of the RAS part as well as of the hydroponic part, the at least one distillation unit is capable to desalinate sea or brackish water, thus increasing capacity of dry regions to produce food within the sustainable system.

[0213] Hence, the implementation of distillation processes contributes to the nitrate balances in multi-loop aquaponics systems to attain optimal growth condition for both fish and vegetation, e.g. plants, by concentrating the hydroponic nutrient solution while diluting the RAS process water.

[0214] In the facility according to FIG. 1 the system for growing vegetation comprises at least one further unit in the form of a bio reactor 8, 10.

[0215] The provision of an unit comprising a bio reactor 10 could be characterized as providing a so called remineralization unit resp. remineralization loop 8 which is capable to further reducing the pH value of solid nutrient parts in the system and to convert at least a great part, preferably the entire part, of these solid nutrient parts into bio-fertilizer.

[0216] It was already indicated in the context of the description of the mechanical filter 4 of the RAS part of the facility 1 according to the invention that at least a great part of the water-soluble particulate parts which are separated due to the process of the mechanical filter unit 4 are conducted from the mechanical filter 4 to the bio reactor loop 8, if provided, including the bio reactor unit 10. An additional settling basin 9 receiving these particulate parts is an option.

[0217] These water-soluble particulate parts could be named as aquaculture waste. They are typically fish sludge, i.e. excrements and uneaten feed.

[0218] The water-soluble particulate parts are getting caught in the gitter, net ore membrane or other separation means as a result of the mechanical filtering process run by the mechanical filter unit 4. The particulate parts getting caught may be separated by applying overpressure which results in flushing out the particulate parts.

[0219] The remineralization loop 8 including the bio reactor unit 10 is designed to conduct an aerobic post treatment of the particulate parts, i.e. of the aquaculture waste.

[0220] The bio reactor unit 10 reduces the pH value of this aquaculture waste. As a result of reducing the pH value it will amount to a range of pH 6 to pH 5, preferably, however, to an amount less than pH 5.

[0221] The reduction of the pH value does preferably not influence the nutrient content, i.e. the nutritional value. The nutrient content of this aquaculture waste after having passed the process of reducing the pH value remains preferably the same.

[0222] However, by reducing the pH value in the bio reactor unit 10 the nutrients of tis aquaculture waste are dissolved in an advantageous manner. This means that running the process in the bio reactor unit 10 results in a pulling out of the nutrients of the aquaculture waste, e.g. fish sludge.

[0223] A range of less than 5 pH leads to a much better nutrient recovery efficiency. The aquaculture waste is effectively converted into bio-fertilizer.

[0224] Due to the pH value and the corresponding suppressed methanogenesis, the effluent is rich in volatile fatty acids (VFAs) which are growth retarding.

[0225] Thus, the bio reactor unit 10 provides an additional process step of an aerobic post-treatment, which provides steps of oxidizing resp. reducing the VFAs so that the effluent of this post-treatment step can be transferred to the hydroponic system 13, 12, 14.

[0226] The transfer of the aquaculture waste into bio-fertilizer is preferably finalized in a device for radial flow settling 11 which may part of the entire bio reactor unit 8, 10.

[0227] Radial flow settlers 11 are a type of filter that supports removing the solid parts of the aquaculture waste and hereby making bio-fertilizer. In a radial flow settler the aquaculture waste already treated in the bio reactor unit 10 as described above enters for instance the center of a thank vertically and flows through a stilling well causing low density solids to be easily settled out of the water column as they settle at the tank. Filtered medium overflows a weir at the top of the settler into a collection trough where the treated medium is sent off to the hydroponics part of the facility (specifics not shown in FIG. 1).

[0228] According to the above mentioned bio reactor unit 10 the treated effluent is being transferred to the hydroponic part 13, 12, 14 of the facility 1, resp. to the hydroponic sump 12 already mentioned.

[0229] When mixing this effluent which has, as described, a low pH value with the medium coming from the RAS part of the facility 1, which is also already pH value-reduced, as described above, a further reduction of the pH value in the hydroponic part 13, 12, 14 of the facility 1 is possible which is advantageous for the growth of the plants according to the above mentioned requirements for the pH level for plants. Irrespective of this at least most part of the nutrients needed for the growth of the plants remain in the effluent transferred from the bio reactor unit to the hydroponic part of the facility.

[0230] When the effluent will have reached the hydroponic part 13, 12, 14 of the facility, i.e. the hydroponic sump 12, the treatment of the medium will continue as described above. This means that due to providing the above mentioned distillation unit 16 the medium passes the corresponding process steps described.

[0231] The bio reactor 10 is positioned in the system between the multi-trophic container 2 and the hydroponic part 13, 12, 14, especially following the mechanical screen filter 4.

[0232] The bio reactor 10 functionally comprises a settling basin 9 plus pump.

[0233] The bio reactor 10 is able to increase to remineralize fish sludge to convert aqua culture waste, i.e. fish excrements and uneaten feed, into bio-fertilizer. The applicant found out that providing low pH, i.e. less than 5.0, led to a much better nutrient recovery efficiency. Accordingly, a remineralization loop can improve sustainability performance. This remineralization loop 8 is provided by a settling basin 9, a bio reactor 10 and radial flow settler 11. The remineralization loop is composed by an upflow anaerobic sludge blanket reactor whereby the phosphorus parameter is used in order to determine the flow of the bio reactor 10. Within this system of the remineralization loop 8 fish sludge is remineralized to convert aquaculture waste, i.e. fish excrements and uneaten feed, into bio-fertilizer. The conducting of the remineralization takes place at a low pH value, i.e. less than 5.0 which leads to a much better nutrient recovery efficiency.

[0234] The recycling aquaculture system, hydroponics and sludge remineralization are displayed independently to constitute the need for different conditions in each subsystem. In the system provided by the invention there is no need to exchange water in addition to the water replacement as consequence of evapotranspiration 15.

[0235] The remineralized sludge, i.e. concentrated liquid fertilizer is only led to the hydroponic system where it is needed. Unnecessary dilution is thus avoided. Of course, global radiation plays an important factor for the evapotranspiration 15 and dependent on the evapotranspiration 15 for the replacement of the water.

[0236] Accordingly, RAS-derived fish sludge is being remineralized and supplemented to the hydroponics.

[0237] The various components, units are connected to each other by unidirectional or bidirectional devices for water and/or substance circulation 17, i.e. corresponding pipelines.

LIST OF REFERENCE NUMBERS

[0238] 1 facility

[0239] 2 multi-trophic container

[0240] 3 fish tank

[0241] 4 mechanical filter unit

[0242] 5 gas exchange unit

[0243] 6 bio filter unit

[0244] 7 sump unit

[0245] 8 remineralization loop

[0246] 9 settling basin unit

[0247] 10 bio reactor unit

[0248] 11 radial flow settler unit

[0249] 12 hydroponic sump unit

[0250] 13 hydroponic part

[0251] 14 hydroponic bed

[0252] 15 evapotranspiration

[0253] 16 distillation unit

[0254] 17 device for water and/or substance circulation