AND PHOTODISSOCIATION SYSTEM

Field of the invention

The invention relates to systems and methods for generating from an input stream of material a plurality of output streams, wherein the intermediary subsystems involved comprise electro-gasification and photodissociation, condensation and other physical and chemical processes, and through which energy conversion is achieved.

Background of the invention

Amongst thermochemical processes, gasification or pyrolysis of organic waste is the process or thermal decomposition of the waste under high temperatures with limited access of air or oxygen. This process is known in the field of energy conversion, whereas the resulting output may contain gas and fuel for internal combustion engines.

Current issues with digestate, manure and domestic wastewater treatment sludge can be identified. For example, after centrifugation, followed by a thermal treatment (with or without liming) or composting, the solid phase streams of manure and digestate are generally transported over long distances. Moreover, wastewater treatment sludge can no longer be used on the agricultural land. Therefore, these sludge streams are now burnt, and for instance recycled as low-grade asphalt, without any recovery of phosphorus or (rare earth) metals.

In the art phosphorus recovery from manure and digestate is based on the chemical binding of orthophosphate (P0 ₄ ) producing FeP0 ₄ (iron sludge), CaP0 ₄ (calcium sludge), NH ₄ MgP0 ₄ .6H20 (ammonium struvite) or KMgP0 ₄ .6H20 (potassium struvite), allowing the recovery of newly formed molecules through decantation. After centrifugation of manure and digestate 60-70% of the phosphorus (P) is found in the solid fraction. Phosphorus recovery is only possible from the liquid fraction, and therefore potentially maximum 30-40% can be recovered in a useful form. It is noted that not all of the phosphorus is under the form of orthophosphate. Further, the iron and/or calcium sludge isn't pure and has a negative value, and moreover, the struvite production is difficult with the high concentration of suspended solids in the liquid fraction. According to scientific studies, the conversion of organically bound phosphorus to orthophosphate is possible through acidification, enzymatic or thermal processes in order to increase the P percentage in the liquid fraction up till 60%. Due to the high cost of chemicals, enzymes and/or energy, the low yield of the phosphate mineral struvite (almost nil) and the negative value of calcium and iron sludge, these processes are not applied for phosphorus recovery from manure or digestate.

In the art, phosphorus recovery from wastewater treatment sludge is particularly owing to the mono-incineration ashes of the (thickened) sludge. The phosphorus can be extracted from the ashes by thermal and physicochemical processes. The residual ashes are then seen as an alternative to phosphate ores. In the ashes is on average per kg 100-120 g phosphorus. Although phosphorus could be recovered this way, the disadvantage of incineration is the production and emission of furans, dioxins and NOx. It is also mentioned that the recovery of phosphorus is only possible after incineration, followed by thermal and physicochemical processes on the ashes.

There is a need for recycling organic waste material with (enhanced) recovery of phosphorus and/or (rare earth) metals, while reducing or eliminating the disadvantages as mentioned above, such as for instance the emission of harmful substances.

Aim of the invention

It is the aim of the invention to have an improved recycling and energy conversion system for organic waste streams, particularly containing phosphorus compounds such as e.g. animal manure, solid fraction of digestate and sludge, while recovering phosphorus, fuels, and (rare earth) metals amongst others.

Summary of the invention In a first aspect, the invention relates to systems and methods for generating from an input stream of material a plurality of output streams, comprising a gaseous stream, and at least two separable liquid streams. In an embodiment thereof the output stream further comprises a solid stream (further also referred to as ashes). The input stream may comprise of a solid stream, a liquid stream, a gaseous phase or mixtures of any combination of those. Further, according to the present invention, the system for generating from an input stream of material a plurality of output streams comprises of a first subsystem and a second subsystem. The first subsystem performs dissociation mechanisms, for example an electro-gasification (related to thermal activity) and photodissociation operation, while generating from the first input stream a first intermediate stream, being at least gaseous, and preferably entirely gaseous. In essence, the system and method in accordance with the invention, exploits dissociation mechanisms based on thermal activity and/or radiation. In an embodiment of the invention, the first intermediate stream further comprises a solid stream. In a further embodiment this solid intermediate stream equals the solid output stream. According to an embodiment of the invention, the first subsystem comprises of a heating and radiating subsystem for heating the input stream.

In an embodiment of the invention the electro-gasification and photodissociation is performed under a high temperature. In an embodiment of the invention, the electro- gasification and photodissociation is performed by applying radiation to the (input) stream being propagated within the first subsystem. In an embodiment of the invention, radiation and heat are generated by a heat radiation source. In other words, the temperature within the first subsystem is mainly generated by a heat source, which is also used as radiation source. The second subsystem is meant for generating from the first intermediate stream a second intermediate stream, having at least a gaseous phase and two separable liquids. In an embodiment of the invention, at least one of the separable liquid streams is at least in part fed back, and hence used as input stream of the second subsystem. In a further embodiment thereof, before the at least one of the separable liquid streams is used at least in part as input stream of said second subsystem, it is used within the heating subsystem of the first subsystem. Moreover, according to the present invention, the second subsystem performs a combined physical and chemical operation, wherein a condensation process mainly characterizes the physical operation. In an embodiment of the invention, the system comprises of a third subsystem for generating from the second intermediate stream, the gaseous output stream, and the at least two separable liquid output streams. In a further embodiment of the invention the third subsystem performs a physical operation. Moreover, the third subsystem may comprise of a pumping subsystem for pumping the gaseous output stream away. According to an embodiment of the invention the first, second and third subsystem are connected in that the operation of the pumping subsystem of the third subsystem realizes a lower than atmospheric pressure within first, second and third subsystems. In an embodiment of the invention, the operating pressure is installed below 300mbar, by use of a vacuum pump connected to the third subsystem. In an embodiment of the invention, the system is further provided with an energy conversion system, being fed by the one of the liquid output streams that is not being fed back to the system, in particular the liquid output stream being oil and the gaseous output stream being (fuel) gas.

In an embodiment of the invention, the system is further fed with the exhaust gases of the energy conversion system or the combined heat and power (CHP) system, being fed with the gaseous output stream and/or the liquid output stream being oil.

In an embodiment of the invention, the system has an organic input stream, whereas one of the two separable liquids of the second intermediate stream comprises the elements P, CI, S, N and hydrogenated halogens, originating from the organic input stream. According to another embodiment, one of the two separable liquids comprises at least 95% of the elements P, CI, N and hydrogenated halogens, originating from the input stream, and preferable this percentage is higher than 95%. For a further embodiment, the solid output stream comprises at most 5% of the elements P, CI, N, C and hydrogenated halogens, originating from the input stream. In an embodiment of the invention, the gaseous phase of the second intermediate stream comprises an amount of NOx (in accordance with the international standards) being less than 65ppmv, preferably a factor 10 less, even more preferably a factor 100 less. In an embodiment, the gaseous phase of the second intermediate stream comprises an amount of furans and dioxins less than the detection limit (ppmv). The above invented system and its accompanied methods have a plurality of control parameters such as the input stream feeding rate, the pressure in the entire system, the recycle rate of the fed back liquid, the temperature and radiation intensity and frequency characteristics. The invented system generates one or more useful products but also consumes energy for steering the one or more mechanical systems involved (like the gas pump and/or liquid recycling pump) and generating the heat for bringing the first subsystem to a desired temperature. As indicated at least one of the output streams can be used for energy conversion. In an embodiment of the invention the first subsystem and/or the third subsystem of the system comprises an optical system designed for a radiation optimally received by the input stream under processing. In a preferred embodiment, there are three stream stages defined for acquiring spectral images, i.e. the input stream, the first intermediate stream and the gaseous output stream, in order to control radiation but also for regulating or fine-tuning the stoichiometric relations in the second subsystem.

It is a second aspect of the invention to provide a control system for determining one or more of the control parameters for operating the system described above in that the objective is achieved of generating an optimal amount and distribution of output streams, i.e. more in particular a maximal amount of useful products and a minimal amount of unwished products (like to be emitted gasses), given the net energy (meaning the extra energy needed compared to the own generated energy), are delivered by the system.

Brief description of the drawings

Figure 1-3 show a schematic description of the system (including subsystems) in accordance with the present invention.

Figure 4 illustrates an embodiment of the system in accordance with the present invention. Figure 5 illustrates an embodiment of the input subsystem in accordance with the present invention.

Figure 6 illustrates an embodiment of the electro-gasification and photodissociation furnace in accordance with the present invention.

Figure 7 illustrates an embodiment of the condenser, separator and gas outlet in accordance with the present invention.

Figure 8 is a picture of the system as schematically represented in Figure 4 in accordance with the present invention.

Detailed description of the invention The present invention provides for an improved recycling and energy conversion system for organic matter mixed in a specific substrate. Possible input streams are manure, digestate, sludge, e-waste, polluted ground and all sorts of polymers. The output is a solid fraction containing all the (rare earth) metals, a liquid fraction containing at least 95% of the initial phosphorus, nitrogen and halogens, a liquid fuel (oil) and a gaseous fuel (methane).

The proposed invention can be applied for the recovery of nutrients from organic waste streams. With state-of-the-art technology, the organically bound nutrients can only be partially recovered. The present invention makes it possible to recover completely phosphorus in the form of phosphoric acid. The process conditions are herewith controlled such that the recovery of nutrients is performed in energy efficient way and with little as possible emissions. The present invention allows for the first time, that in regions where there is a large occupancy of phosphorus, organic waste streams containing phosphate (as there are manure, digestate and sludge) are locally valorized, rather than being transported over long distances. In addition, for wastewater treatment sludge that can no longer be used on agricultural land, and therefore is burnt, the ashes are a mixture of phosphorus and metals, where the phosphorus can only be separated with an extra thermal en physicochemical step.

In accordance with the present invention, a new technique based on electro- gasification and photodissiciation, by means of radiation (e.g. UV), is provided allowing to produce ashes without any phosphorus left. In particular, the ashes comprise (rare earth) metals and (quasi) no carbon, this latter as would be resulting generally from a pyrolysis process. Moreover, by means of the system and related methods used, the phosphorus is separated in a liquid phase in the form of phosphoric acid. This makes further processing easier and enables complete recovery of phosphorus, nitrogen, halogens and metals.

While referring to Figure 1, the invention provides that an input stream 200, in particular of organic waste material, being largely unknown in composition or even having varying composition, is decomposed by means of a system 100 into a predetermined plurality of output streams 310, 320, 330 in that it comprises of a gaseous stream 310, and at least two liquid streams 320, 330, being separable. Moreover one or more of the output stream products is considered as being useful, while having for instance a further technical use, e.g. for the combustion of an energy generating system, and hence having an economic value; alternatively unwished products are (rather) not formed at all. Therefore the system 100 as realized is quite a challenge in that (i) even from a pure stoichiometric point of view (static view) the amount of atoms will most likely not match and (ii) even if they do the variety of processes (decomposition, recombination in the chemical step) have other dynamics (kinetics). Moreover while the electro-gasification and photodissociation occurs at elevated temperatures, the obtaining of liquids requires a condensation step, hence a strong difference in temperature profile occurs along the operational stream of the entire system and the processes occurring therein tend to be very temperature dependent.

The invented system is adapted for generating one or more predefined output streams by having means for curing stoichiometric mismatches. Hence, as an example, in an embodiment, part of one or more of the output streams is recirculated and/or a special known input stream is used. Further, means for temperature control along at least part of the operational stream of the system are provided. In an embodiment for instance, the place can be selected for injecting the recirculated output stream used for cooling in the second subsystem. Particularly for matching the unknown or varying character of the input stream with the electro-gasification and photodissociation step, the electro- gasification and photodissociation subsystem is provided with means for adapting the electro-gasification and photodissociation operations. Therefore, according to an embodiment an appropriate radiation spectrum, temperature range and pressure conditions are chosen.

It is noted that recycling of output streams is always done in partially in order to avoid accumulation. Moreover curing mismatch and temperature control per se are not sufficient, in that over-dimensioning of the system or subsystems and operating in the wrong conditions (e.g. too high temperature), besides practical concerns, do lead to inefficient production, in the sense that the required net energy to be injected in the system might not outweigh the benefit of the produced output streams. Said otherwise the (net) energy input per recovered mass unit of useful product (e.g. phosphorus, rare earth metals) should be minimized. The following examples are illustrative for this. While the electro-gasification and photodissociation process performs better in low pressure, up to vacuum conditions, this has obviously consequences for the energy demand on the pump side. While the electro-gasification and photodissociation process performs better in high temperature conditions, this has obviously consequences on the heat generation side.

In summary one might state that the invented system is made suitable for generating from an unknown and/or varying first input stream of material a predefined set of one or more output streams (containing useful products, e.g. phosphorus) while avoiding unwished products (e.g. emissions like NOx, i.e. nitrogen oxide air pollutants nitric oxide (NO) and nitrogen dioxide (N0 ₂ ), furans and dioxins) by having various means for controlling (e.g. by recirculated streams, specific temperature ranges, stoichiometric relationships and other operational conditions of subsystems) to ensure that the joint process is efficient. Moreover, due to the system processes described, output streams are compared to the art far better recovered and/or recycled, characterized by its low emission and resulting in final output materials that are appropriate for new and high- grade (industrial) applications.

Detailed description of the embodiments

While Figure 1 shows the system 100 according to the invention in a rather simplified way, indicating input stream 200 and output streams 310, 320, 330 as already mentioned above, the representation of Figure 2 shows yet more detail by introducing the subsystems 140, 150, 160 of the system 100. Appearing in both Figure 1 and Figure 2, the input stream 200 can be a solid stream, a liquid stream, a gaseous phase or mixtures of any combination of those. The output streams 310, 320, 330 comprise a gaseous stream 310, and two separable liquid streams 320, 330. As an example, the gaseous stream 310 comprises of methane. In an embodiment of the invention the first liquid output stream 320 comprises of water, mixed with acids e.g. comprising halogens and phosphorus, while the second liquid output stream 330 being oil such as fuel oil or diesel.

Further referring to Figure 2, the intermediate streams 170, 180 between the subsystems 140, 150, 160 are given, more in particular the first intermediate stream 170 being the output of the first subsystem 140 acts as input of the second subsystem 150, whereas the second intermediate stream 180 being the output of the second subsystem 150 is the input of the third subsystem 160. The first subsystem 140 performs an electro-gasification and photodissociation operation, while generating from the input stream 200 the first intermediate stream 170, in an embodiment being entirely gaseous. The second subsystem 150 is meant for generating from the first intermediate stream 170 a second intermediate stream 180, according to an embodiment having a gaseous phase and two separable liquids. Moreover, the second subsystem 150 performs a combined physical and chemical operation, wherein a condensation process mainly characterizes the physical operation and wherein the hydrolysis of the halogens characterizes the chemical operation. The system 100 further comprises of a third subsystem 160, e.g. performing a physical operation, for generating from the second intermediate stream 180, the gaseous output stream 310, and two separable liquid output streams 320, 330. The system 100 according to the invention is schematically described with even more detail in Figure 3. Here, the output of the system 100 further comprises a solid output stream 340. According to an embodiment of the invention, another first intermediate stream - than the gaseous first intermediate stream 170 - being a solid stream can be generated as output of the first subsystem 140. As depicted here, this solid first intermediate stream may equal the solid output stream 340. Further, the first subsystem 140 comprises of a heating subsystem 141 for heating the input stream 200. For the second subsystem 150, a feedback 190 is illustrated, indicating that one or both of the separable liquids being part of the second intermediate stream 180 are (partially) fed back, and hence used as input of the second subsystem 150. Moreover, the third subsystem 160 comprises of a pumping subsystem 161 for pumping the gaseous output stream 310 away. In an embodiment the first, second and third subsystem 140, 150, 160 are connected in that the operation of the pumping subsystem 161 of the third subsystem 160 realizes a lower than atmospheric pressure within first, second and third subsystems 140, 150, 160. Also shown in Figure 3, one of the liquid output streams 320 is fed back and subsequent (partial) feedback 195 functions as cooling for the second subsystem 150. The system 100 is further provided with an energy conversion system 390, being fed by the one of the liquid output streams 330 that is not being fed back to the system 100, in particular the liquid output stream 330 being oil. The gaseous output stream 310 being e.g. fuel gas, can also feed the energy conversion system 390, which is for instance a combined heat and power (CHP) system or a cogeneration platform. Subsequently, exhaust gases 395, i.e. for example C0 ₂ and H ₂ 0 damp, being emitted from the energy conversion system 390 can then be fed back to the system 100, acting as further input of the system 100, while preheating the input stream 200. In an embodiment (not shown), the energy conversion system for the gaseous output stream 310 differs from the energy conversion system for the liquid output stream 330.

The invention is now further described via illustrative embodiments as depicted in Figure 4-7. Figure 4 illustrates an embodiment of the system 400 in accordance with the present invention. Organic waste material 405, such as animal manure or digestate, including a solid fraction thereof, is introduced as input stream in the input container 410, possibly provided with means for assisting in grinding the received organic waste material 405. Just below the input container 410, the input stream of organic waste material 405 is guided into an electro-gasification and photodissociation furnace 420 together with a gaseous stream 406 being the exhaust gases of the CHP 390 fed with at least one of the output streams 465, 475 (or 330, 310 in Figure 3). As illustrated in Figure 4, the input container 410 and the electro-gasification and photodissociation furnace 420 are vertically arranged, meaning that the input stream flow F (see Figure 6) is in vertical direction. The electro-gasification and photodissociation process performed within the furnace 420 is determined by a thermochemical decomposition of the organic waste material 405 at elevated temperatures, e.g. between 800 and 1200°C. At least in principle this process occurs in the absence of oxygen (or any halogen). In this particular example, low pressure l-300mbar, close to vacuum is also set as one of the operating condition. With the electro-gasification and photodissociation process a simultaneous change of chemical composition and physical phase is achieved. The gaseous phase 435 resulting from the thermochemical process is led to a gas pipe 440 for continuing further processing of the system 400, while the solid residues 425 fallen down by gravitation and/or left over from the process, are captured in a receptacle in the bottom part of the furnace 420, and can be removed using the solid outlet 430 mounted below the furnace 420. The gaseous phase 435 is propagated in the gas pipe 440 by rising, which is particularly supported due to the high temperatures reached in the oven 420. The temperature in the gas pipe 440 is e.g. 600-1000°C. At the end of the gas pipe 440, the pipe structure is curved, hereby guiding the gaseous phase 435 to the upper part of the condenser 450. Within the condenser 450, operating at low pressure, the gaseous phase 435 is being cooled and hence physical as well as chemical processes occur. The cooling process is enhanced by means of sprinklers, atomizing a liquid with a particular flow, and also catalyzing preferred new compounds. The resulting output at the bottom of the condenser 450, comprises a gaseous stream, being the non-condensed part 475, and two separable liquid streams, the condensed part 455, and is subsequently led to a separator 460. More particularly, after condensation, the condensed part 455 comprises acids (e.g. comprising hydrogenated halogens) and oil, first in a separable mixture to be then split apart by decantation 480 into polar and nonpolar molecules. After decantation 480, oil 465 is reduced and separated from the acids 485 generally mixed with water. The oil 465 can now be reused as fuel for a combustion chamber or CHP 390, whereas the 'acids + water' stream 485 can be (partially) kept apart via the leftover stream 495 or can be (partially) fed back to the input of the system 400 via the feedback stream 415. The feedback stream 415 is thus reducing water and energy consumption of the system 400, by either recirculating (part of) the 'acids + water' stream into the system, or either functioning as heat recovery, while cooling the condenser 450 via provided apertures therein. The non-condensed part 475, here e.g. methane (CH ₄ ), is pumped away via the gas outlet 470 towards a cogeneration platform 390 and hence further recycled as a combustion gas. Similarly to or comparable with the first, second and third subsystem 140, 150, 160 of the system 100 shown in Figure 2-3, a first, second and third subsystem 401, 402, 403 of the system 400 are indicated in Figure 4.

A few parts of the system 400 are now discussed into more detail. First, Figure 5 illustrates an embodiment of the input container 510 in accordance with the present invention. Arranged again in vertical set-up, the input container 510 is amongst others determined by its tubular shape 512 and its vertically mounted rotating main shaft or central axis 511. The input container 510 has for example dimensions of height h (e.g. 1000 mm) > diameter d (e.g. 850 mm). A supporting frame 514 is connecting the central axis 511 with the tubular surface 512. At certain heights scrapers 513 are concentrically positioned within the container 510. While no real restrictions on the size of the solid fraction particles are made, these scrapers 513 will assist in grinding the organic waste material, before it is led towards the electro-gasification and photodissociation furnace. The auger 515 extending out of the inner as well as outer surface of the input container bottom 516, assists in the mechanical lead-through of the input stream towards the oven, mounted below the input container 510. Moreover, the input container bottom 516 comprises of a double-layered structure in order to accommodate in the heat recovery, when for instance 'hot' feedback stream, coming from the gas pipe 440 (shown in Figure 4), is injected back into the system via the bottom 516. In the upper area 517 of the input container 510, atmospheric pressure is present, whereas close to the bottom 516 there is under pressure.

According to an embodiment, the electro-gasification and photodissociation furnace 620 is also characterized by a tubular shape, as illustrated by the perspective view in Figure 6 (a), whereas Figure 6 (b) shows the top view of the oven 620. Concentrically positioned in a vertical arrangement, an amount of electrodes 622 are surrounding the central axis 621. The electrodes 622 are for instance made of an aluminum alloy (e.g. lconel-601) enabling resonance in organic compounds, by emitting radiation at particular wavelengths, more particularly in the UV range. Each bond (C-C, C-H, C-O...) of the organic compound has a particular vibration frequency, and can be resonated. Due to the low pressure within the oven 620, radiation will maximally arrive at or collide with the organic molecules and the phosphorous bounds need less energy to break. The electrodes 622 are circumvented by a parabolic plate 629, reflecting the radiation emitted by the electrodes 622, and concentrating it to the center of the oven 620, as indicated by the arrow R. Further, due to the low pressure in the furnace 620, there is no complex isolation material required at its inner surface 628, resistant to high temperatures, low pressure and aggressive environment. This is particularly illustrated in Figure 6 (b), wherein the concentric area A between the parabolic plate 629 and the inner surface 628 of the oven 620, is a zone of under pressure, and hence acting as isolation. While referring back to Figure 6 (a), at multiple heights, possibly regular positions, rotating scrapers 623 are mounted within the central chamber 627. Each of the scrapers 623 is assembled close to a disc 624, made out of a particular material. Further, a solid receptacle chamber 631 is provided in the lower area of the electro- gasification and photodissociation oven 620, for capturing all non-gaseous material. The opening or outlet 630 is used to exit the solid stream 425 being ashes comprising of (rare earth) metals. While this lower area is a cooled zone, the vacuum here will function as barrier for heat transfer (cfr. low heat conduction coefficient). A gas pipe 640 is extending from the central chamber 627 of the oven 620, for diverting the gaseous phase towards further processing.

With Figure 7 an embodiment of the condenser 750, separator 760 and gas outlet 770 in accordance with the present invention is illustrated and herewith described into more detail. At low pressure, for example less than 300 mbar, and a temperature less than 1200°C, condensation of the gaseous stream 735 directed from the gas pipe 740 into the condenser 750 is further catalyzed by means of sprinkling a liquid, such as for instance water or any other liquid, via the nozzles or sprinklers 780 provided at (regular) heights within the condenser tube 750. Temperature is regulated in the condenser and is for example lower than 20°C, preferably lower than 18°C. The sprinkled liquid can be a fed back liquid 415 (partially) deducted from the liquid output stream 485 or else can be another externally introduced liquid, i.e. not fed back from the system but coming from outside of the system. The sprinkled liquid is moreover enhancing the formation of preferred new compounds corresponding the proportions C, N, O and H within the condenser tower 750, particularly determined by its size and dimensions. The relationship between C/N/O/H is for instance 1/0,3-0,5/0,9-1/2-3. Moreover, the distance L between the sprinklers 780, along the height H of the tower 750, as well as the relation H/L are important parameters in the design of the condenser 750. As an example, a distance L of 1000mm is used for a height H of 3000mm. The resulting output at the bottom of the condenser 750 still comprises a non-condensed part 775 being gaseous, while the condensed part 755 comprises of two separable liquids, i.e. acids (e.g. comprising halogens such as phosphorus) and oil. The gaseous condensed and liquid non-condensed parts 755, 775 are split using a separator 760, and a gas outlet 770, all or not provided with a vacuum pump to pump the gas away towards a further (recycling) application such as for instance a cogeneration platform.

Phosphorous is recovered in a liquid form as phosphoric acid. This opens the possibility to concentrate the recovered phosphorous with state of the art evaporation systems using mechanical vapour recompression, increasing the value of the end product and lower the transportation costs. According to a further embodiment, an additional gasification step at 270-330°C of the input stream 200 is provided, which makes the phosphorous bounds easier to brake in our system 100 and lowers the overall energy consumption for phosphorous recovery with at least 15 %. This pretreatment lowers the complexity in the second step as described above, optimizing the reorganization of atoms. The best recovery of phosphorous is seen when this pretreatment precedes the conditions maintained in the oven of the system 100.

According to a further preferred embodiment, in order to cure stoichiometric mismatches, a hydrogen rich input stream is added.

According to an embodiment, an oven 420 with a volume of 200 liters can treat 20-50 kg per hour of dried manure with a dry matter of 80%.