DE102012212298A1 - Digestate treatment system comprises separating device for separating digestate into liquid phase and solid phase, evaporator unit for separating the liquid phase into water, first phase manure and solid residues, and a briquetting device - Google Patents

Abstract

Digestate treatment system (1), comprises a separating device (3) for separating a supplied digestate into a liquid phase and a solid phase, an evaporator unit for separating the liquid phase into water, a first phase manure and solid residues, preferably by supply of low-temperature thermal energy and a briquetting device for pressing the solid phase into the briquette shape. An independent claim is also included for processing digestate, comprising providing a digestate, separating the digestate into a liquid phase and a solid phase, separating the liquid phase into water, a first phase manure and solid residues by supplying low-temperature thermal energy, and pressing the solid phase into briquette shape.

Description

The present invention relates to a digestate treatment system.

Known systems for digestate treatment are used to process fermentation residues in biogas plants, but they are also used in agriculture (animal breeding, manure processing, liquid manure utilization) or in the support of industrial processes for recycling industrial residues. In particular, in the field of biogas plants has been recognized that a disposal and processing of the resulting digestate is necessary. Known approaches are provided here by the water industry, in particular the drinking water treatment. From there it is known to clean digestate by means of multi-stage filter systems, for example via ultrafiltration and reverse osmosis. However, this only leads to an incomplete and unsatisfactory treatment of fermentation residues, which still leaves substantial residues.

Another disadvantage of these known filtration techniques is that high cost expenditures are necessary, which limits the profitability of such treatment plants. The maintenance and operating expenses have also led to such filtration systems being used only as special applications and in individual cases, but not across the board.

Thus, the present invention was the object of specifying a Gärrestaufbereitungssystem, which mitigates the above perceived disadvantages as much as possible.

The invention solves the underlying object by proposing a Gärrestaufbereitungssystem with a Separatoreinrichtung for separating a supplied digestate in a liquid phase and a solid phase, an evaporator for dividing the liquid phase in water, a first fertilizer phase and solid residues, preferably by supplying low temperature Heat energy, and a Brikettierungseinrichtung for pressing the solid phase in briquette form. Under low temperature are understood in the context of the invention temperatures below 200 ° C, preferred ranges of low temperatures in the invention are below 100 ° C, more preferably at 90 ° C. In return, the term "high temperature" is used in the context of the invention for temperatures which are above the low temperature. Preferred ranges here are temperatures above 400 ° C, more preferably above 500 ° C. In one embodiment, a high temperature in the range of 550 ° C is proposed.

The invention makes use of the knowledge that it can be used to propose a holistic system for processing digestate, in which the digestate produced can be repeatedly processed into more usable products in an integrated system. The invention makes particular use of the fact that in the evaporator device, the liquid phase largely separated from the solids is treatable by dehydration to even higher-quality fertilizer as the first fertilizer phase. In known systems, the digestate is applied either directly or after coarse separation of solids in the form of manure and the like as a fertilizer. However, the fertilizer of the first fertilizer phase produced by the invention is much higher quality and can also be sold in smaller quantities at higher prices. Furthermore, the system according to the invention provides a possibility to press the separated solids in briquette form and to make available for subsequent use possibilities.

Another advantage of the invention lies in the fact that biogas plants can be constructed and operated in conjunction with the system according to the invention and when using the method according to the invention, without having to set up the otherwise required detection surfaces. It is no longer necessary to tie regenerative energy production from biomass to farmland for the application of fermentation residue, because the fermentation residues are completely processed and refined. On the basis of the manure products produced in the system and method, an ecologically safe and more easily controllable use in the agricultural sector is made possible due to the adjustable in the parameter range fertilizer concentration. In any case, in the medium term, this also leads to lower soil and groundwater pollution in the agricultural sector.

In an advantageous embodiment of the invention, the evaporator device is adapted to separate by evaporation from the liquid phase water, and run from the evaporator means to offset the remaining after dehydration residue of the liquid phase with sulfuric acid, sulfuric acid solution, phosphoric acid, or a phosphoric acid solution such that an ammonium sulfate - or phosphate solution is obtained, and to carry out these from the evaporator device, and to carry out any remaining solid residues from the evaporator device. Preferably, the ammonium sulfate or phosphate solution is concentrated to an ammonium sulfate or phosphate content of 30% or higher, preferably 40%. This is possible because the liquid phase of the fermentation residue, which is supplied to the evaporator device, contains ammonium nitrogen (NH4 cations). These remain as salt back when out of the Liquid phase water is evaporated. By adding this remaining after evaporation residue with sulfuric acid, sulfuric acid solution, phosphoric acid, or a phosphoric acid solution, the resulting ammonium sulfate or phosphate solution can be removed from the evaporator device, for example by means of appropriate piping systems. The resulting ammonium sulfate or phosphate solution serves as a particularly high quality fertilizer. The remaining at the end of this process in the evaporator solid residues are preferably collectable by appropriate collection means in the device and removable by means of appropriate execution means from the device, so that they can be made available for subsequent use.

In a preferred embodiment of the present invention, the evaporator device comprises a two-stage or multi-stage vacuum evaporator for the evaporation of the water from the liquid phase. Here, the knowledge is used that the boiling point of the water can be further reduced by reducing the pressure within the evaporator, and the evaporation can also be done by supplying low-temperature heat energy below the boiling point of water under normal conditions (100 ° C).

The system according to the present invention preferably comprises a conduit system for recirculating the water discharged from the evaporator means. The line system is preferably designed to recirculate the water for cooling purposes and / or as process water for supplying the system components with low-temperature heat energy. Preferably, the line system is connected to heat exchangers, which are set up for heat recovery of waste heat from other parts of the system or for the delivery of heat to other parts of the system. Excess water, which is substantially pure, can also be removed from the piping to be made available for other uses.

According to a further preferred embodiment of the fermentation treatment system, the briquetting device is adapted, in addition to the solid phase fed to it, to press the solid residues, which are supplied to it by the evaporator device, together with the solid phase in briquette form. This allows a maximum utilization of the total feedstock of the fermentation residue. Preferably, a mass flow of the solid residues, which are output from the evaporator means, mixed with the solid phase and introduced after mixing by suitable supply means in the briquetting.

Preferably, the briquetting device is set up to dry the briquettes, and in this case to supply the briquetting of the briquetting during drying to the briquettes for drying. The briquetting device preferably has a dryer. The dryer is either adapted to generate heat automatically, or alternatively adapted to use externally supplied heat and deliver it to the material to be dried. Furthermore, the briquetting device preferably has a press, which is connected downstream of the drying unit and is adapted to press the at least partially dried fed solid phase in briquette form. In the context of the invention, the term "briquette" is understood to mean any compressed solid form, for example also pellets. Also, pelletizers are therefore to be understood as Brikettierungseinrichtungen within the meaning of the invention. Further details on the briquetting device will be discussed later in this description. The digestate conditioning system further preferably comprises a thermal utilization device configured to provide low temperature thermal energy by firing the dried briquettes supplied thereto, the low temperature thermal energy being generated by heat transfer means of the evaporator means and / or the dryer unit within the briquetting means, and / or which is adapted to provide medium temperature and / or high temperature thermal energy by firing the dried briquettes supplied to it. Preferably, the device for thermal utilization is adapted to burn a regenerative energy source, which is selected from the following: biomass, in particular green waste and / or crops grown for thermal use; and / or biogas. The use of biogas or a hybrid use of biogas and biomass is particularly preferred because these two components in addition to the digestate in biogas plants are available anyway and the connection of the system according to the invention to a biogas plant is accordingly economically particularly advantageous.

In a further advantageous embodiment, the device for thermal utilization is set up to provide low-temperature heat energy by means of combustion of the regenerative energy supply supplied to it, wherein the low-temperature heat energy can be supplied to the evaporation device by means of heat transfer means, and / or is arranged to supply it by means of combustion regenerative energy source to provide high-temperature thermal energy. Particularly preferred is a combination of the combustion of briquettes and externally supplied energy sources, because this significantly higher Amount of heat for the system processes can be provided.

The system according to the invention with a device for thermal utilization is furthermore preferably set up such that the low-temperature heat energy can be supplied for drying by means of heat transfer means of the dryer unit within the briquetting device.

In addition to the low-temperature heat energy but also the high-temperature heat energy within the system can be effectively used. For this purpose, the Gärrestaufbereitungssystem according to a further preferred embodiment, a power conversion device for converting heat energy into electrical energy, wherein the high-temperature heat energy can be supplied by means of heat transfer means of the power conversion device. The power conversion device is preferably configured to supply low-temperature heat energy in the form of waste heat by means of heat transfer means to the device for thermal utilization and / or the briquetting device and / or the evaporation device.

Further preferably, the power conversion device is adapted to convert the thermal energy supplied to it by means of a steam turbine process into electrical energy. For this purpose, the power conversion device preferably has a steam turbine unit, which is set up for heating and evaporation of a working fluid by means of the high-temperature heat energy supplied by the device for thermal utilization, such that within a pressure vessel of the steam turbine unit, a vapor pressure is built up to relax the vapor pressure by means of drive a turbine, which cooperates with a generator, such that the generator converts the rotational movement of the turbine into electrical energy, and for cooling the working fluid, removal of heat as low-temperature heat energy, preferably for the evaporation device and / or for the drying device. This is preferably ensured by means of a line system, particularly preferably by means of the process water line system.

The system is advantageously further developed in that the power conversion device is set up to feed the electrical energy into a power grid.

Further preferably, the steam turbine unit is adapted to be operated in an ORC (Organic Rankine Cycle) process. The ORC process is essentially characterized in that a working fluid other than water vapor is used to operate the steam turbine, namely an organic working fluid with a boiling point well below the boiling point of water.

According to a further alternative embodiment of the invention, instead of a steam turbine unit, a steam expansion motor is provided in the power conversion device. Here, instead of a turbine, a piston is driven by the steam expansion.

According to a further preferred embodiment of the digestate treatment system, the briquetting device is adapted to dry the solids supplied to it before pressing in briquette form by supplying heat energy to a dry matter content of more than 50%, preferably in a range of 55% to 60% to press in briquette form, and post-pressing the briquetted solid, preferably by means of supply of ambient air nachgetrocknen so that a dry matter content of above 70%, preferably in a range of 74% to 76% is obtained. By dry matter is meant that constituent of a substance or mixture which remains after removal of water. The dry matter content and the water content of the substance or mixture thus complement each other to 100%. The reference point for the determination of the dry matter content is the respective mass fraction. The determination of the dry matter content is carried out by known methods, for example by means of microwaves or by use of an evaporation balance. With regard to the determination by means of microwave measurement technology, reference is made, for example, to the DynFAS technology of Braunschweigische Maschinenbauanstalt AG.

Preferably, the briquetting device has for drying a belt dryer which can be operated in the low to high temperature range, or another dryer which is preferably operable up to the high temperature range. For pressing in briquette form, preferably a wet briquetting machine is used. A particular advantage of wet briquetting - based on the entire briquetting device - the lower energy consumption compared to conventional briquetting. The lower energy requirement results from the fact that a wet briquetting device compresses the mass supplied to it while it still has some moisture. The moisture contained in the mass fed to the wet briquetter ensures that the mass can not spontaneously ignite during pressing, which is a risk with conventional pressing methods and completely dried press materials. This in turn means that the heat generated during the pressing process does not have to be dissipated in the briquettes. Just this, the pressing process in the briquettes accumulating According to the invention, heat is not dissipated after the pressing process or during it, but remains in the briquettes and serves for further drying of the briquettes in a post-drying process subsequent to the briquetting process. Optionally, the briquetting device thus has an after-dryer, in which the pressed briquettes are further dried. Particularly preferably, the briquetting device for the after-dryer on means for supplying air, such as ambient air on.

According to an alternative embodiment of the method according to the invention, the briquetting device does not have a wet briquetting device but a conventional briquetting device. The alternative briquetting device is equipped with a dryer, which performs a drying of the supplied solids as far as possible before briquetting, for example, to a dry matter content of 85% or higher. Following the pressing process, in the alternative briquetting device, cooling medium, for example in the form of cooled air, is actively fed in a downstream process, thus removing the heat present.

In a further preferred embodiment of the invention, the device for thermal utilization is adapted to carry out remaining residues from the device as a second fertilizer phase after firing. This embodiment is particularly advantageous if the residues are phosphate and kalihaltig (which is usually the case depending on the supplied digestate). These components survive the firing within the thermal utilization device essentially without damage. The exported residues can be further used as phosphorus or potash fertilizers. Thus, the inventive system ensures the upgrading of the digestate in an integrative manner to a first fertilizer phase, a second fertilizer phase and pure water. In addition, the system provides electrical energy which is available for operating the plant and for feeding it into a power grid when the system is additionally combined with a power plant as described above.

The digestate treatment system preferably has a combustion unit adapted for combustion of biomass within the device for thermal utilization and / or a cogeneration unit for providing additional heat energy for the device for thermal utilization. The preferably provided cogeneration plant is also configured in a particularly preferred embodiment to use excess heat energy for generating electrical energy.

According to an alternative embodiment, the device for thermal utilization has a gasification or pyrolysis unit. This unit also supplies coal as an additional residue after gasification or pyrolysis, which coal can be carried out as "biochar" from the thermal utilization device and used externally.

The device for thermal utilization is further preferably configured to provide waste heat as low-temperature heat energy, for example by means of heat exchangers and the proposed process water pipe system.

The Gärrestaufbereitungssystem is also advantageously further developed in that the separator comprises a separator for the separation of solids, preferably by means of a press screw separator or by sedimentation, in a first stage, and a centrifuge for the separation of suspended matter in a second stage.

• – Bereitstellen eines Gärrestes,
• – Trennen des Gärrestes in eine Flüssigphase und eine Festphase,
• – Aufteilen der Flüssigphase in Wasser, eine erste Düngerphase und Feststoffrückstände, vorzugsweise mittels Zuführen von Niedertemperatur-Wärmeenergie, und
• – Pressen der Festphase in Brikettform.

The invention further relates to a process for the treatment of digestate. The invention solves the underlying problem with such a method, in particular by using a system according to one of the preferred embodiments described above, wherein the method comprises the steps:

• Providing a digestate,
• Separating the digestate into a liquid phase and a solid phase,
• - Splitting the liquid phase into water, a first fertilizer phase and solid residues, preferably by supplying low-temperature heat energy, and
• - Pressing the solid phase in briquette form.

With regard to the particular advantages of this method, reference is made in particular to the above statements on the digestate treatment system according to the invention, in which the method is used.

• – Verdampfen von Wasser aus der Flüssigphase,
• – Versetzen des nach Wasserentzug verbleibenden Rests der Flüssigphase mit Schwefelsäure oder einer Schwefelsäurelösung, oder Phosphorsäure, oder einer Phosphorsäurelösung derart, dass eine Ammoniumsulfatlösung oder eine Ammoniumphosphatlösung erhalten wird, vorzugsweise mit 40% Ammoniumsulfat- oder Ammoniumphosphatanteil,
• – Ausführen des verdampften Wassers in ein Leitungssystem zur Rezirkulation,
• – Ausführen der eventuell nach Wasserentzug verbleibenden Feststoffrückstände,
• – Pressen der ausgeführten Feststoffrückstände gemeinsam mit der Festphase in Brikettform,
• – Trocknen der Briketts mittels Abwärme, die beim Pressen in Brikettform entsteht
• – Verfeuern der getrockneten Briketts und/oder eines zugeführten regenerativen Energieträgers und Bereitstellen von Niedertemperatur-Wärmeenergie, Mitteltemperatur- und/oder Hochtemperatur-Wärmeenergie,
• – Zuführen der bereitgestellten Niedertemperatur-Wärmeenergie oder Mitteltemperatur-Wärmeenergie zu dem Schritt des Verdampfens und/oder Trocknens
• – Wandeln der bereitgestellten Hochtemperatur-Wärmeenergie in elektrische Energie, vorzugsweise mittels eines Dampfturbinenverfahrens,
• – Zuführen der bei der Wandlung in Form von Abwärme entstehenden Niedertemperatur-Wärmeenergie zu dem Schritt des Verfeuerns und/oder des Trocknens und/oder des Verdampfens,
• – Abscheiden von Feststoffen aus dem Gärrest, vorzugsweise mittels eines Pressschneckenseparators oder mittels Sedimentation, in einer ersten Stufe,
• – Abscheiden von Schwebstoffen mittels einer Zentrifuge in einer zweiten Stufe,
• – Trocknen des Feststoffs vor dem Pressen in Brikettform mittels Zufuhr von Wärmeenergie auf einen Trockensubstanzgehalt von über 50%, vorzugsweise in einem Bereich von 55%–60%,
• – Nachtrocknen des in Brikettform gepressten Feststoffs im Anschluss an das Pressen, vorzugsweise mittels Zufuhr von Umgebungsluft, derart, dass ein Trockensubstanzgehalt von oberhalb 70%, vorzugsweise in einem Bereich von 74% bis 76%, erhalten wird,
• – Ausführen der nach der Verfeuerung verbleibenden Rückstände als zweite Düngerphase

The process according to the invention for the treatment of digestate is preferably further developed by one, several or all of the steps:

• Vaporizing water from the liquid phase,
• Adding the residue of the liquid phase remaining after dehydration with sulfuric acid or a sulfuric acid solution, or phosphoric acid, or a phosphoric acid solution such that an ammonium sulfate solution or an ammonium phosphate solution is obtained, preferably with 40% ammonium sulfate or ammonium phosphate fraction,
• - Run the evaporated water into a recirculation piping system,
• - carrying out any remaining solids after removal of water,
• Pressing of the executed solid residues together with the solid phase in briquette form,
• - Drying of the briquettes by means of waste heat, which arises during pressing in briquette form
• Burning the dried briquettes and / or a supplied regenerative energy carrier and providing low-temperature heat energy, medium-temperature and / or high-temperature heat energy,
• Supplying the provided low-temperature heat energy or medium-temperature heat energy to the step of evaporating and / or drying
• Converting the provided high-temperature heat energy into electrical energy, preferably by means of a steam turbine process,
• Supplying the low-temperature heat energy resulting from the conversion in the form of waste heat to the step of firing and / or drying and / or evaporation,
• Separating solids from the fermentation residue, preferably by means of a press screw separator or by means of sedimentation, in a first stage,
• Separating suspended matter by means of a centrifuge in a second stage,
• Drying the solid before pressing in briquette form by supplying heat energy to a dry matter content of more than 50%, preferably in a range of 55% -60%,
• After-drying of the briquetted solid after pressing, preferably by supplying ambient air, such that a dry matter content of above 70%, preferably in a range of 74% to 76%, is obtained,
• - Perform the remaining residues after firing as a second fertilizer phase

Further advantages of the method according to the invention are immediately apparent from the analogous advantages of the embodiments of the digestate treatment system in one or more of the preferred embodiments described above. For this reason, reference is also made to the above statements regarding the advantages of the developments of the method according to the invention.

The invention will be described in more detail below with reference to a preferred embodiment and the attached figures.

Hereby show:

1 a digestate conditioning system 1 , and

2 a schematic detail view of the system according to 1 ,

The system 1 has a separator 3 on. The separator device 3 has a digestate port 5a on, as well as a solids outlet 7a and a liquid outlet 9a , The Separatoreinrichtung is adapted to the supplied digestate, indicated by arrow 5 to separate into a solid phase and a liquid phase in one or more stages as described above with respect to the preferred embodiments. The liquid phase is by means of the liquid outlet 9a in a liquid phase line 9 carried out while the solid phase to remove the solid phase from the solids outlet 7a is executed, for example, a means of transport 7 or in a solid line (a conveyor belt or similar known means of transport).

The system 1 also has a briquetting device 11 on. The briquetting device 11 has an inlet 7b for the solid phase up. The through this inlet 7b fed solid phase is dried in the briquetting and pressed in briquette form. The briquetted substances are used as briquettes from a briquette outlet 15a from the briquetting device 11 executed.

The system 1 further comprises an evaporator device 13 on. The evaporator device 13 has a liquid phase connection 9b which is for supplying liquid phase from the line 9 from the separator device 3 Coming is set up. The evaporator device 13 is configured, as described above with reference to the preferred embodiments, to divide the supplied liquid phase into various components. For example, by means of vacuum evaporation, water is separated from the liquid phase and via the water outlet 23a executed, for example, in a process water pipe 23 , The remaining after removal of water substances are added (in a manner not shown) supplied sulfuric acid or sulfuric acid solution and concentrated to an ammonium sulfate solution. This ammonium sulfate solution is used as a first fertilizer phase by means of a fertilizer outlet 21a from the evaporator device 13 executed, for example, in a first fertilizer line 21 , After these process steps still remaining solid residues are by means of a solids outlet 19a from the evaporator device 13 executed and for example on a means of transport 19 promoted, which may be designed as a belt conveyor or similar known funding. About this funding 19 become the solid residues of the briquetting device 11 fed where they share with the over the means of transport 7 fed solids can be pressed in briquette form.

According to the embodiment shown in the figure, the system 1 also a device 27 for thermal utilization. The device 27 for thermal utilization has a connection 15b for the supply of briquetted solid. Furthermore, the device has 27 for thermal utilization a connection 29a for supplying a, preferably regenerative, energy carrier (indicated by arrow 29 ). The device 27 for thermal utilization is adapted to burn the briquetted solid and / or the, preferably regenerative, energy carrier, or alternatively to gasify or undergo pyrolysis. This heat energy is released, which for example via the heat transfer medium 17 to the briquetting device 11 , or via the heat transfer medium 25 to the evaporator device 13 is deliverable. The heat energy coming from the device 27 for thermal utilization at the outlets 17a . 25a is preferably low temperature heat energy, more preferably at a temperature around 90 ° C. In any case, it is relevant that at the corresponding connections 17b . 25b the briquetting device 11 or the evaporator device 13 corresponding heat energy arrives, so that in the intervening cable paths 17 . 25 , which may be connected, for example, with a process water pipe system, and corresponding heat transfer means may be provided.

Preferably, the device provides 27 for thermal utilization not only low-temperature heat energy available, but also high-temperature heat energy. This is via a corresponding connection 31a and heat transfer means connected thereto 31 to a connection 31b a power conversion device 35 directed. The power conversion device is preferably equipped with a steam turbine unit or a steam expansion motor. In this case, mechanical work is converted into electrical energy essentially in the relaxation of the working fluid used (pressurized steam). This can be realized according to a preferred embodiment by means of an ORC method.

The power plant 35 has a connection 37a for dissipating the generated electrical current or the generated electrical energy, indicated by arrow 37 , on. In the power generation process by the cooling of the working fluid resulting waste heat is via a connection 28a the power conversion device 35 in a corresponding heat transfer medium 28 issued. This is according to the attached figure with a corresponding connection 28b the device 27 connected to the thermal utilization, there to the from the power plant 35 dissipated waste heat of the device 27 to provide for thermal utilization. Alternatively, it is also possible to make the waste heat available to a process water line system or to feed it to one of the other system parts of the system in order to feed in heat energy there. This can in particular the briquetting 11 or the evaporator device 13 be.

During the implementation of the device 27 For thermal utilization introduced briquetted solid and / or renewable energy carrier resulting in heat energy residues are, in particular in ash form, through an outlet 33a the device 27 designed for thermal utilization. These residues serve as a second fertilizer phase (indicated by arrow 33 ) for further economic use.

In 2 is the briquetting device 11 of the system 1 shown schematically in detail. The briquetting device 11 has a dryer 39 on. The dryer 39 has one or more ports connected to the means of transport 7 . 19 cooperate and by means of which or which of the briquetting device 11 fed solids into the dryer 39 be initiated. In addition, the dryer points 39 Means for supplying heat energy from the heat transfer means 17 to be provided. The heat energy supplied may be either low-temperature thermal energy or high-temperature thermal energy. Alternatively, the use of medium temperature heat energy is possible, which is in the temperature range above 90 ° C and below 500 ° C. Preferably, the heat source is transported by means of a heated fluid, for example gas.

The briquetting device 11 also has a briquette 41 which is preferably a wet briquetting machine. The briquetting machine 41 At least partially dried solid is fed. This preferably has a dry matter content of 55 to 60% according to a preferred embodiment of the method. In the briquetting device, according to a preferred embodiment, heat energy is released during pressing, which results in that after passing through the wet briquetting device the dry matter content is approximately 70%.

Furthermore, the briquetting device according to 2 a night dryer 43 on. In the after-dryer 43 For example, the briquetted material is preferably mixed with ambient air via the supply 45 A further drying of the briquettes takes place according to a preferred embodiment in cooperation with the heat energy still present in the briquettes, until they have a dry matter content of preferably 75 to 85%. Then the dried briquettes are used as fuel from the briquetting device 11 executed, indicated by arrow 15 ,

In summary, the advantages of the solution according to the invention thus are as follows: With the system according to the invention for digestate treatment and the analogous process for digestate treatment, it is possible to completely disassemble the supplied digestate into its components and to refine them so that their economic value in Sum clearly above that of the digestate. At the same time, electrical energy is generated in the process, which can be fed in and used economically. Heat generated in the process is simultaneously returned to the system and the process, resulting in a further improvement of the economy and increase the efficiency of the overall system. As a result, an economically acceptable use of the system of digestate treatment is possible.

Claims (16)

Digestate conditioning system ( 1 ), - a Separatoreinrichtung for separating a supplied fermentation residue in a liquid phase and a solid phase, - an evaporator means for dividing the liquid phase into water, a first fertilizer phase and solid residues, preferably by supplying low-temperature heat energy, and - a Brikettierungseinrichtung for pressing the solid phase in briquette form. System ( 1 ) according to claim 1, wherein the evaporator device is adapted to - remove by evaporation from the liquid phase water and run out of the evaporator device, - the remaining after dehydration residue of the liquid phase with sulfuric acid, sulfuric acid solution, phosphoric acid or a phosphoric acid solution such that an ammonium sulfate solution or ammonium phosphate solution is obtained, and to carry out this from the evaporator device; and - to carry out any remaining solid residues from the evaporator device. System ( 1 ) according to claim 2, comprising a conduit system for recirculating the water discharged from the evaporator means. System ( 1 ) according to any one of the preceding claims, wherein the briquetting device is adapted, in addition to the solid phase fed to it, to press the solid residues, which are fed to it from the evaporator device, together with the solid phase in briquette form. System ( 1 ) according to one of the preceding claims, wherein the briquetting device is adapted to dry the briquettes. System ( 1 ) according to one of the preceding claims, with a device for thermal utilization, which - is adapted to provide low-temperature heat energy by burning the dried briquettes supplied to it, wherein the low-temperature heat energy can be supplied to the evaporator device and / or the briquetting device by means of heat transfer means, and / or - is arranged to provide medium temperature and / or high temperature thermal energy by firing the dried briquettes supplied to it. System ( 1 ) according to claim 6, wherein the means for thermal utilization is adapted to provide by means of combustion of the supplied regenerative energy carrier low-temperature heat energy, wherein the low-temperature heat energy can be supplied by means of heat transfer means of the evaporation device, and / or - is arranged by means of firing the their supplied regenerative energy medium to provide medium and / or high-temperature heat energy. System ( 1 ) according to claim 6 or 7, wherein the low-temperature heat energy can be supplied to the briquetting device by means of heat transfer means for drying. System ( 1 ) according to one of claims 6 to 8, with a power conversion device for converting heat energy into electrical energy, wherein the high-temperature heat energy can be supplied to the power conversion device by means of heat transfer means. System ( 1 ) according to claim 9, wherein the power conversion device is adapted to supply low-temperature heat energy in the form of waste heat by means of heat transfer means of the means for thermal utilization and / or the briquetting and / or the evaporation device. System ( 1 ) according to one of the preceding claims, wherein the power conversion device is adapted to convert the thermal energy supplied to it by means of a steam turbine method into electrical energy. System ( 1 ) according to one of claims 3 to 11, wherein the briquetting device is adapted to dry the solid supplied to it before being pressed in briquette form by supplying heat energy to a dry matter content of more than 50%, preferably in a range of 55% -60% To press the solid in briquette form, and post-press the briquetted solid, preferably by supplying ambient air, in such a way that a dry matter content of above 70%, preferably in a range of 74% to 76%, is obtained , System ( 1 ) according to one of claims 4 to 12, wherein the means for thermal utilization is adapted to carry out remaining residues from the device as a second fertilizer phase after the firing. System ( 1 ) according to one of claims 7 to 13, wherein the separator comprises a separator for the separation of solids, preferably by means of a press screw separator or by sedimentation, in a first stage and a centrifuge for the separation of suspended matter in a second stage. Process for the treatment of fermentation residues, comprising the steps: Providing a digestate, Separating the digestate into a liquid phase and a solid phase, - Splitting the liquid phase into water, a first fertilizer phase and solid residues, preferably by supplying low-temperature heat energy, and - Pressing the solid phase in briquette form. The method of claim 15, comprising one, several or all of the steps: Vaporizing water from the liquid phase, Adding the residue of the liquid phase remaining after dehydration with sulfuric acid, or a sulfuric acid solution, or phosphoric acid, or a phosphoric acid solution such that an ammonium sulfate or ammonium phosphate solution is obtained, preferably with 40% ammonium sulfate content, - Run the evaporated water into a recirculation piping system, - carrying out any remaining solids after removal of water, Pressing of the executed solid residues together with the solid phase in briquette form, Drying of the briquettes by means of waste heat produced during pressing in briquette form, Burning the dried briquettes and / or a supplied regenerative energy carrier, and providing low-temperature heat energy and / or high-temperature heat energy, Supplying the provided low-temperature heat energy to the step of evaporating and / or drying, Converting the provided high-temperature heat energy into electrical energy, Supplying the low-temperature heat energy resulting from the conversion in the form of waste heat to the step of firing and / or drying and / or evaporation, Separating solids from the fermentation residue, preferably by means of a press screw separator or by means of sedimentation, in a first stage, Separating suspended matter by means of a centrifuge in a second stage, Drying the solid before pressing in briquette form by supplying heat energy to a dry matter content of more than 50%, preferably in a range of 55% -60%, After-drying of the briquetted solid after pressing, preferably by supplying ambient air, such that a dry matter content of above 70%, preferably in a range of 74% to 76%, is obtained, - Perform the remaining residues after firing as a second fertilizer phase, and - converting the provided high-temperature heat energy by means of a steam turbine process into electrical energy.

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