DK168480B1 - Process and plant for the treatment of organic matter - Google Patents

Abstract

Biochemical treatment of matter subjected to the action of microorganisms, decomposing in a plurality of successive biochemical reactions and an installation with a view to implementing the process; the matter to be treated in the solid or pasty state is circulated continuously in a single vessel with a flow section which is small in relation to its length, at the two ends of which there is an entry and an exit, and differentiating working zones (42,43,44,45) are defined along the path of the matter within the single reactor and along a crown segment in plan view, each being assigned to a biochemical reaction and to a dominant specific flora, in particular the conditions for recycling the matter and for introducing solid or gaseous elements or reactants are defined by zones and preferably the gaseous atmospheres of the volumes corresponding to each zone are isolated from each other by a transverse partition. <IMAGE>

Description

DK 168480 B1

PROCEDURE AND PLANT FOR TREATMENT OF ORGANIC MATERIAL

The present invention relates to the biological treatment of materials or substrates under the influence of colonies of microorganisms, in which the general treatment involves at least two successive phases, each corresponding to a dominant biochemical reaction.

More specifically, the invention relates to a process and plant for use in the practice of this process which permits the production of biogas under improved conditions, preferably obtained by bacteriological fermentation of organic matter. The invention will then be described in connection with this application.

In particular, the present invention is adapted to provide a method of practice which allows the utilization and recovery of waste from cities, agriculture and any industrial origin by fermentation in an anaerobic medium, which fermentation under the influence of bacterial colonies is accompanied by production of a gas comprising a substantial proportion of methane and so-called "biogas".

More particularly, the invention relates to the utilization of residual residues, which in themselves are initially solid.

It is interesting to be able to process the materials that are subjected to the anaerobic fermentation process in a continuous manner in one reactor, which obviously allows the work, energy consumption and maintenance investment and running costs to be reduced.

35 Six types of methods are traditionally distinguished which are performed in a continuous manner and are used for treating liquids; a continued mixing by mechanical or pneumatic stirring in the fermentation vessel; 5 - anaerobic contact by recirculating a portion of the outgoing microorganisms recovered in an internal sheath in the fermentation vessel, in order to increase the average bacterial concentration; Anaerobic filter with binding of the bacteria to an inactive package in the container; fluidized bed maintaining a solution of a gasket at an ascending flow of the liquid to be treated; - USAB, with a wrapper inside the fermentation vessel to precipitate aggregates of bacterial sludge; 20 - piston with a progressive front of the material in a homogeneous manner. An approximation thereto is effected by passing effluents through a series of containers of the infinitely mixed types.

EP-A-0 048 675 discloses an apparatus for treating biochemical liquid waste.

This apparatus comprises an enclosed space forming a reactor provided with vertical partitions defining the volume of gas and of material in which each of the fermentation phases takes place.

However, while it is relatively easy to initiate continuous processes of a liquid feedstock, the continuous process is more or less difficult in the case of solid or dough waste.

It is an advantage of the invention to provide a method and a plant for carrying out the method which enables continuous processes from solid or doughy waste to be initiated.

Thus, methods are known in which the materials to be processed are stored in baskets which move through a tunnel while immersed in a liquid medium, the transport being accomplished by a complicated mechanical plant such as a screw, chain or scraper. ; It is obvious that these plants are difficult to control and represent a high degree of investment and risk of mechanical malfunctions that have not allowed industrial development.

There is also known a method of treating raw material comprising a high dry matter content wherein the solid material is placed in a solution to produce a dough-like mass which allows a viscous behavior substantially related to a semi-liquid mass; thus, garbage of urban origin can be utilized and treated, in which case the raw material is brought back to a granulogical size between 0 and 100 mm, dissolved in a ratio of dry material between 30 to 35% of dry extract, and the material by force from a shaft or piston is introduced into a cylindrical reactor where it must be subjected to a treatment cycle with an appropriate hydraulic retention time (RTH) of the order of 15 to 25 days.

FR Patent Application No. 2,481,873 has the subject of a fermentation installation for continuous production of methane gas from liquid or non-liquid materials soaked in a liquid. Furthermore, the size and capacity of each of the corresponding volumes either during aerobic fermentation or during anaerobic fermentation is calculated prior to the start of the fermentation, and no recycling of the materials and no control of the biological parameters during the course is provided. of the fermentation.

5

It is an advantage of the invention to allow recycling of the materials and modification of different capacities and thus the retention time corresponding to each previous step during the fermentation.

10

Also known is a method of continuous fermentation comprising placing the substrates (such as fertilizers) in a vertical silo; the materials are introduced at the top and removed from the bottom, which, however, involves technical problems; these methods are further limited in the present volume due to the vertical configuration of the plant, which limits the application of the method to large plants.

20 Although the implementation of a continuous process shows advantages in terms of application, there are disadvantages of maintaining in a closed volume under the same conditions a material which is at the beginning of the degradation and which is therefore close to materials already in the process. at the end of the degradation and is advanced in the complex methanation process by bacteriological solution, so that the average ratios (temperature, composition, gas produced, degree of recirculation, pH, etc.) of this heterogeneous medium do not necessarily correspond to the optimal conditions in each phase. characterized by a dominant biochemical reaction in the pervasive process.

This advantage of the continuous process, however, remains relatively theoretical in itself, because it assumes that each portion is itself of a homogeneous composition, so that the different phases of the methanization process are identical for each component; if the portions, especially in the case of residues of urban origin, have a substantially constant composition over time, each portion feeding the reactor will, by definition, contain elements 5 of completely non-uniform composition varying from rapidly fermenting materials to products whose reaction to on the contrary, the effect of bacterial digestion will be much slower; so as to find again that the disadvantage previously stated, namely that even in a continuous reactor, the portions will contain material which, at a relatively advanced rate of degradation, some time after the beginning of the cycle, while other components have remained very delayed .

Finally, FR Patent Application No. 2,475,524 proposes a fermentation process comprising two phases; a pre-digestion producing carbon dioxide gas which takes place in a digestive pit, and a digestion phase producing methane which takes place in a fermentation channel separate from the digestive pit and fed with material coming from the latter.

It is an advantage of the invention to propose a method and plant which allows to carry out these two phases in a single reactor.

Furthermore, it is known that the biological process defined as the methanization of organic products, in fact, results from four consecutive complex biological reactions carried out in microbial environments of various species acting in symbiosis.

Traditionally, four successive phases of degradation are distinguished by the action of the following predominant bacterial populations: hydrolysis: the biopolymers, of which the organic material is composed (glucides, proteins and lipids), are dissolved in metabolized substances by the microorganisms. This phase must proceed in an aerobic or anaerobic medium similar to the 5 substrates, - acidogenesis: the preceding intermediates are metabolized by acid-forming bacteria in a complex mixture rich in one side of volatile fatty acids and other compounds having more than two carbon atoms, and on the on the other, a mixture rich in acetate, carbon dioxide and hydrogen, - acetogenesis: under the influence of a new group of bacteria, the organic acids and other compositions of 15 more than two carbon atoms are converted to carbon dioxide, hydrogen or acetic acid; the phases acidogenesis and acetogenesis are sometimes regrouped, - methanogenesis: during this last phase under the influence of 20 a final group of microorganisms, acetate is converted to biogas, while the carbon dioxide is reduced by hydrogen.

It is noted that the rate of hydrolysis itself is lower than the rate of methanogenesis, itself lower than the rate of acidogenesis, and that the rate of reaction is biologically directly related to the rate of reproduction of the bacteria.

Therefore, it is desirable and at the same time the first object of the present invention to provide a method which links the technological and economic benefits of the investment and in the course of the work of the continuous process with a constant adaptation of the parameters for controlling the treatment to the successive The following phases of the process where each phase corresponds to a specific dominant reaction, which can therefore be controlled under appropriate and adapted conditions.

Another object of the invention is to provide facilities which, depending on the design and initial construction, can offer 5 interior design options and versatility that allow any quantitative or qualitative change in the material to be treated. In fact, it is very difficult to know the exact composition of a city, region, or even a land of waste or residues to be treated. Furthermore, the percentages of components will evolve over time with production and consumption habits.

Therefore, the process of the invention will allow to optimize the process of methanization during which the different dominant reactions are carried out one after the other in a single reactor, but in fact separated into different work zones, each of which is associated with a dominant reaction.

20

To this end, the invention relates to a process for the continuous treatment of organic raw materials in solid or dough form by fermentation under the influence of colonies of microorganisms, and in which at least two successive phases are each, each corresponding to a dominant biochemical reaction of the species in which the materials to be treated are introduced into at least one reactor where they undergo the action of microorganisms, such as bacterial colonies, which produce an anaerobic fermentation 30 for the purpose of producing biogas, causing the materials to continuously circulate between a a main inlet and an outlet located at the two ends of the reactor, the material passing during a hydraulic retention time corresponding to the resting time required for the average treatment of the materials included in the feed and the method characterized by comprising: DK 168480 B1 8 - Continuously allowing the materials to circulate in the reactor longitudinally and along a non-linear, concave and especially curved path, 5 - performing at least one removal operation of at least one material stream in a suitable part of the web to re-introduce it upstream to produce at least a partial recirculating the treated materials specific to a dominant reaction zone, the entry point and the withdrawal point of the recycled materials being mainly at the insertion point or at the execution point of the virtual volume defining said zone within the reactor, respectively, 15 - regulating the rate of recirculation in said zone to adjust the average retention time of the material in that zone by the time of reproduction of the colonies of specific microorganisms in that zone, and 20 - to control conditions specific to a dominant reaction in each of the subsequent zones at regular intervals. to continue taking physical and / or chemical and / or biological precautions adapted to allow the determination of the state of the material and the development conditions of the dominant reaction in each zone.

For the purpose of initiating the method, the fact of generating the rate of recirculation in a zone (the material is taken from the end of the zone 30 and re-upstream at the entrance to that zone) serves to adjust the retention time of the material in this zone. the time of recovery of the colonies of microorganisms (biomass) specific to this zone, thus avoiding leaching.

According to another form of initiating the process, the circulating medium is introduced in a manner specific to each of the zones, especially gaseous substances such as methane or carbon dioxide suitable to chemically affect the equilibrium of said medium. as a function of the dominant reaction in each zone.

More specifically, in order to limit the gas atmosphere prevailing over each zone, an upper transverse wall is provided at sites corresponding to the exit of a dominant reaction zone and to the inlet of a subsequent zone corresponding to another dominant reaction. thereby isolating the gas atmospheres located above each zone.

More specifically, within the scope of implementing the invention for the production of biogas through bacteriological fermentation of residues, within a small passageway cross-section and having a large path length corresponding to the path of movement of the treated material, four subsequent 20 zones are defined, each corresponding to a dominant reaction, viz. : a) a first zone destined for a hydrolysis process and located between the main inlet and a first intermediate inlet; b) a second zone downstream along the path of the treated material and destined for an acidogenesis process, which second zone lies between the first intermediate inlet and a second (c) a third zone again downstream along the path of the treated material and destined for an acetogenesis process, said third zone lying between said second intermediate inlet and a third intermediate inlet; d) a fourth zone lying downstream corresponds to DK 168480 B1 10 a methanogenesis test This zone is located between the third intermediate inlet and the outlet of the material in the form of effluents, and controlling the supply conditions, the recirculation conditions, the temperature conditions and the re-injection ratios of biogas in each zone as a function of the dominant reaction in this zone.

More specifically, in a particular zone of the mixture in the mass of materials to be treated, intermediate metabolites which are specific to the specific bacterial flora for the dominant reaction occurring in that zone can be introduced.

Even more particularly, said metabolites are in solid form and are selected in the family which include: a) glucose-containing products introduced into the zone for acidogenesis, 20 b) acetate-rich materials introduced into the zone for the formation of methane.

The invention also relates to a plant for use in the practice of the above-mentioned method.

For this purpose, the invention relates to a plant for the treatment of organic matter in solid or dough form and under the influence of microorganisms such as bacterial colonies, in particular for the production of biogas, the plant being of the kind consisting of closed container as contained in the one end is provided with a main inlet for the material to be treated, and at the other end an outlet for the dissolved effluent material, characterized in that the container is formed with a small constant cross-section relative to its length, and a plan view of a web as a ring segment DK 168480 B1 11 is connected to an insert, an embodiment and has means for collecting and introducing materials or biogas to a disengaged central part located in the middle of said ring segment, which constitutes a technical area, including means for controlling and directing the treatment in the container at its various points.

More particularly, the plant along its path comprises the means for removing material from the flow of material 10 in the passage in the plant and said means for introducing material into the flow of said material in the passage, which means are arranged on the concave wall of the plant. container.

Preferably, the container on its upper portion and projecting from its roof forming wall comprises substantially vertical transverse partitions extending into the material in the course of the reaction, these partitions being adapted to divide the free space above the doughy material. in circulation in the reactor while delimiting each other independent airspace, each volume being connected to a central unit designed to separately collect the samples taken during these gaseous phases corresponding to each of the volumes and to a particular composition.

25

Further features and advantages of the invention will become apparent from the following description which is given by way of example in a particular embodiment, illustrated as a non-limiting example of the attached drawings, in which:

FIG. 1 is a cross-sectional view of a reaction vessel according to the invention; FIG. 2 is a perspective view of a processing unit utilizing a reaction vessel according to the invention; FIG. 3 is a plan view of the plant of FIG. 2, FIG. 4 is a perspective view of a unit roof element; FIG. 5a and 5b show in plan view an alternative embodiment of a methanizing reaction vessel which includes virtual work zones; FIG. 5a shows the circuits for the material and FIG. 5b the gas-10 sen circuits.

According to all the figures and in particular figs. 1, which shows a cross-sectional view along line I-I of FIG. 3, it can be seen that the container is partially buried and that at its bottom it consists of a trench dug in the soil itself, especially by mechanical means such as a trench excavator.

The gutter 1 has a shape which extends upwardly and according to the drawing has a V-shaped cross-section and thus comprises two 20 walls 2 and 21, extending obliquely from the corresponding upper edge 3-3 'down to the bottom of the gutter 4.

The gutter follows, as can be seen in FIG. 2 and 3, is a curve and preferably has a discontinuous circular path, and thus consists of a circular section 5 interrupted by a zone 6 which allows external access to the center of the ring 7.

The gutter thus defined defining a shaped base consisting of the two inclined walls 2, 2 'is covered with a surface or cladding wall arranged against and parallel to the walls 2, 2'.

In the example shown in the drawing, a cover is made up of a concrete wall 8 which in a known manner rests on a gravel bed 9.

DK 168480 B1 13

The concrete wall forms a cladding that joins the bottom with a V-shaped cross-section in the gutter and is provided with a reinforcing shoulder conforming to the circular configuration of the walls 2, 2 '.

5

By choice, the concrete can be cast after application of sliding formwork, which is moved as the work progresses.

The gutter can be covered with any covering material which can ensure the tightness of the walls, especially elements made of reinforced resin or of formed steel sheets or even possibly of foils reinforced with a liquid-tight flexible material (plastic or reinforced rubber film).

It can be seen from FIG. 1, it is seen that the upper part of the concrete walls 8 is extended by a body 10, 10 which joins the upper edges 3, 3 'of the gutter.

20

These bodies will constitute supports which constitute consideration for receiving the coverage elements described below.

25 It can be seen from FIG. 1 shows that the open channel is closed at its top of a closure and cover element, one of which is shown in perspective in FIG. 4th

This element is advantageously made of a reinforced resin and is dimensioned to follow in a plan view the curve of the gutter, while its flat edges 12 and 12 'are deflected to their position on the supports 10 and 10', respectively, with intermediate sealing agents formed from fungi. bony or alveolar material impregnated with bitumen 13, 13 '.

DK 168480 B1 14

A series of preferably rearwardly bent rods 14, 14 'embedded in the support 10 protrude with their upper end to extend through the flange 12, 12' and, by bolts, secure the attachment of this flange to the supporting spring layer, and the It will be appreciated that each cover member 15 forms a vault which is therefore self-supporting and can be quickly placed in place and secured to the tapered edges 10, 10 'of the lower walls 8, 8' of the gutter.

The elements 15 are arranged one after the other to form a ring or ring segment located on the ring segment 5 constituted by the gutter.

The circumferential cover elements 15, 15 ', 15' 'at 15 comprise their opposing edges joining means, in particular in the form of recesses which interact with sealing layers (such as strips of compressible and alveolate material impregnated with bitumen), so liquid-tight -ness from one element 15 to the other is ensured.

20

From a central unit 23 there are extended upper pipelines 24, 24 'which collect and centralize the gas produced in a portion of the container and optionally reintroduce it into the recirculation circuit via the pipes 22, 22' after pressure application 25 in the central unit 23.

A significant advantage of the invention is the great flexibility of the reactor's capacity which has not been definitively determined.

30

It is therefore possible to provide a container formed as a quarter circle or as a semicircle, which can then be expanded by the addition of a new quarter circle to thereby increase the capacity while maintaining the unit and the homogeneity throughout; It will be understood that leaving the ends of iron bars protruding through the final end cap is easy during the performance of the reinforced concrete lining 8, 8 'DK 168480 B1 15, so that after the destruction of this end cap the gutter can be easily extended and subsequently extended walls 8, 8 'to produce a new ring section as an extension of the original container.

Therefore, the container, although presenting a large capacity, may be somewhat inconvenient to the surroundings and may perform its storage function in accordance with a substantial volume 10 without, however, exceeding an abnormal height.

The object of the invention provides the possibility of placing in the center of (partially closed) ring the central installations, which can thus operate the entire reactor, whose points 15 are all equidistant from the central zone.

In particular, where reagent elements (reagents or formal control fluids) must be added to the product under treatment, the length of pipelines 20 is significantly reduced.

Where the container is used as a methanization reactor for fermentation and bacterial reaction of waste, the lowering of energy consumption due to the low height of the transducer is a significant advantage in using the container of the invention, especially in the event of starting the pumps for introducing the material.

A transverse closure is provided on the cover elements located at the ends where the ring segment formed by the gutter is interrupted.

It can be seen from FIG. 2, it is seen that the end cover members 16, 16 'thus comprise a transverse wall 17, which in itself has a flange 18 which rests on and is fixed to a transverse support extending upwards from a transverse wall DK 168480 B1 16 ( not shown in the drawing) and closes both side walls 8, 8 'of the gutter in flight with both ends.

In FIG. 2, it can be seen that from a central source containing suitable pumps and compressors can radiate radial conduits 22, 22 '(visible in FIG. 1) leading to a recirculation container or nozzles 23' which dive into the container and therefore allow pressurized back into the viscous mass which is under the treatment of gases rich in methane, thereby producing the desired effect of the process, namely increasing the yield of methane production.

FIG. More specifically, Figures 5a and 5b provide an example of an embodiment of a plant provided for treating residues or, in particular, waste for a methanization process according to the process of the invention.

FIG. 5a shows the circuit of the solid or doughy material to be treated.

FIG. 5b shows the circulation of the gas phases.

It will be seen that within the term of this example, a reactor is defined which defines a single volume and as previously described in the general form of a ring segment.

Here, the reactor 30 is connected with its concave surface to a central area 32 by a plurality of channels or pipelines 33, 34, 35, 36, 37, 38.

These pipelines constitute the means of transferring, introducing and recirculating material circulating in the reactor 30.

It must be clarified that pipelines are shown in pairs shown, for example, 33 and 34, each being associated with a particular direction of circulation, which is done for the sake of clarity and for understanding the drawings; but it will be easy to produce a single pipeline which, in the direction of use, can serve to return both the recycled material from the reactor 30 to the technical area 32 and vice versa.

According to this embodiment, the reactor forms a single enclosure in which the materials introduced from the feed 39 continuously circulate to the outlet 40 through which the treated materials, i.e. the reacted, return to the technical area 32 .

However, within the sieve of this embodiment, a plurality of transverse walls are provided in the upper portion of the reactor's volume as shown in FIG. 1 and in FIG. 5a and 5b under the reference numeral 41.

These transverse walls are arranged to define in the upper part of the enclosure (intended to receive the gaseous atmosphere) 4 zones, which will correspond to 4 work zones, each associated with a dominant reaction.

25

For the sake of clarity, 3 transverse walls 41 are provided in an equidistant manner, thereby defining zones 42, 43, 44 and 45 by substantially the same volume.

30

However, it is obvious that the arrangement of the transverse walls 41 can be adjusted as a function of the required, that is, as a function of the volume of the zone corresponding to a particular reaction; each zone can thus take within a suitable length within the total volume of the reactor enclosure, which can only be defined by the application of the transverse wall 41 to DK 168480 B1 18.

It is clear that this wall can be easily removed and displaced along the ring if it becomes necessary as a function 5 of the subsequent development of the supply to attach a larger volume to a particular work zone ..

It will be seen that it is particularly possible to achieve a flexible and flexible structure because it is very easy to change the 10 virtual boundaries of the consecutive work zones, even while keeping the reactor intact, as will be described below.

Technical area 32 comprises a plurality of means allowing operation of the plant, namely: - elements for the introduction and mixing of the materials to be processed, and in particular from the upstream storage 46 and arriving at the central zone 32 through 20; channel 47.

The area 32 further comprises circulating means, for example pumps intended to ensure the movement of the treated materials which will be converted into a dough-like mass, as will be explained below.

Thus, the arriving materials arriving through the channel or connection 47 will be brought into suitable granulation and converted into a doughy and liquid 30 form which allows a rheological circulation of the products by mixing with the liquids coming from the converter and thus being directed towards the central area at 40.

Optionally, the arriving materials must already be subjected to a temperature rise to bring them to a physical state where they are able to undergo the first phase of the general methanization process, namely the hydrolysis that takes place in zone 42 .

Obviously, due to the use of an elongated web having a small cross-section and the dough-like shape of the material, local conditions can be obtained in each zone which are different and adapted to the dominant reaction in the corresponding zone without interference. with the adjacent zones.

Thus, in the first zone 42 which is associated with the hydrolyzing conditions, for example, of temperature and of mixtures or also of pH, viscosity, etc., adapted to the evolution of the hydrolyzing reaction must be produced.

15 In particular, and by considering FIG. 5b, it can be seen that it is possible to accelerate the methanization process at an aerobic phase, for example, in zone 42, by injecting oxygen and even air into a blowout end 51, 52 which covers the lower wall from a freshly stored gas 50 reactor.

However, the optionally oxygen-rich gas-containing atmosphere produced in zone 42 does not pose a risk of contamination of the subsequent zones due to the transverse flaps or walls 41 which isolate the gas-containing atmosphere in each zone from each of the others.

Thus, the gas collected from zone 32 through an upper pipeline can be recovered in the technical area 32 '(which is adapted to treat the gas circuit) and undergo the useful separation and compression operations (see Figure 5b).

35 The materials arriving through the pipeline 39 are gradually pushed downstream by the subsequent introduction of new materials which are being processed.

In zone 42, the materials move slowly according to an appropriate hydraulic retention time (TRH) and with the development of this progress, the colonies of bacteria corresponding to the dominant reaction in this zone (hydrolysis) develop and spread.

Therefore, upon arrival near transverse flap 41, the materials are rich in colonies of bacteria corresponding to the hydrolyzing treatment.

According to the invention, through the pipeline 33, a portion of the materials reached at the end of the hydrolyzing phase is continued and through the technical area 32 recycled to the incoming pipeline 39 where these materials are mixed with the freshly arrived material. to supplement the yeast mixture and to seed with colonies of bacteria exactly corresponding to the specific operation to which the arriving materials are to be subjected hereafter.

A plurality of probes are provided within the technical area for controlling the material, and these probes are shown schematically at 60, 61, 62, 63. They are connected by circuits 64, 65, 66, 67 to monitoring means 68, thus centralizes the information that allows the selected parameters to follow the evolution of the reactions in the successive zones.

30

Thus, these probes receive the measurements of the temperature along the entire web as well as the measurements of the viscosity, the acidity of the medium and the measurements corresponding to the composition of gases drawn from the gas-containing atmosphere present in each zone, and the flow rate of these gases which can be is measured at the gas return pipes 70, 72, 74, 76 respectively --- mf ^^^^ DK 168480 B1 21 (Fig. 5b).

It is therefore possible to know immediately from the technical area the degree of progress of the reactions in the materials arriving at the end of a zone or in the passage of the zone, and this makes it possible to exert influence on the conditions prevailing in that zone. to accelerate, slow down or correct and optimize the progress of the reaction.

10

For this purpose, various parameters can be used, such as the rate of recirculation of the material from the return tube 33 (when zone 42 is considered).

It is also possible to influence the process by intervening in the gas circuit, as seen in FIG. 5b, thereby interfering with the composition or propulsion of the gases which are re-injected into the corresponding zone of the exhausting ends 51, 52.

20

The transport of the materials is continued on a regular basis as it is not inhibited by any obstruction in the solid or dough phase (only the gas phase is insulated by the transverse partitions 41).

25

Therefore, the hydrolyzed material enters zone 43 where the monitored parameters (temperature, pH, viscosity, etc.) are adjusted to create the optimal developmental conditions for the microbial flora specific to the acidogenetic reaction.

As noted above, the material entering zone 43 and coming from hydrolysis zone 42 receives via pipeline 34 a portion of the material recycled from pipeline 35, with the result that the material treated in zone 43 initially receives a yeast mixture, which is specific for the reaction and the microbial flora corresponding to this reaction.

Therefore, the material leaving the acidogenetic zone 43 will enter the acetogenetic zone 44 and, as previously described via the inlet tube 36, will receive a recycled portion of the materials leaving the acetogenetic zone, which materials consequently enters the yeast mixture at the intake of the acetogenetic zone. and specific microbial poisons necessary for the acetogenesis provided in this zone.

Finally, the same phenomenon occurs when the materials rich in acetate leave the acetogenetic zone and enter the methanization zone 45; the materials are then added, via the conduit 38, to the recycled substance from the outlet 40 and allow entry from the beginning of the methanogenetic phase of the bacterium specific to this reaction, which can then be developed, the conditions of temperature, pH, etc. .., mentioned above, is adapted and monitored in this zone as a function of the desired parameters.

Also, at the inlet to each zone, elements capable of interfering with the reactions can be added either as metabolites or chemical fluids, which can produce favorable conditions for the development of the dominant reactions in each zone.

For example, materials rich in glucose will be introduced from the hydrolysis phase, while materials rich in acetate will be introduced at the intake of the methanogenetic zone.

The same goes for the gas flows; it can be seen that zone 42 can advantageously receive an initial supply of oxygen to start the reactions in an aerobic phase.

35

The biogas produced, specific to each zone, can - with advantage - be recovered and, after an analysis of the composition, re-injected either downstream or upstream into another zone where it, when injected via the exhaust ends, enters the dough mass for to create favorable chemical or biochemical conditions for the dominant reaction of the zone.

Therefore, it has become possible, for example, to inject methane in pure form or in the form of biogas produced at the site, in that particular or in a corresponding zone to adjust and correct the pH.

It is also possible from the fresh gas source 50 to conduct hydrogen arriving via the lower exhaust ends 78, 79, 15 into the passage of the material in the methane forming zone 45, the hydrogen blown under pressure thereafter contributing to the reduction of CO methane.

FIG. 5b does not show the details, including in particular ports, valves, compressors, etc. ..., in the technical area 32 'intended for regulating the gas circulations; It is seen that the gas as the final product can be discharged via the conduit 80 towards a purification phase 81 and stored in a gas storage 82. It is noted that circuits of the ends for re-injecting the material into the circulation at the bottom have been shown divided into four zones for to reproduce the drawings more clearly; the ends may actually be directly connected to the central technical area or zone 32 'and it is sufficient to check, by motorized means, the connection of the ends to the circuit or circuit to provide the injection of a suitable gas into the bounded zone, which therefore will not be geographically determined.

Claims (18)

A process for the continuous processing of organic raw materials in solid or doughy form by fermentation 5 under the influence of colonies of microorganisms, and in which at least two successive phases are passed, each corresponding to a dominant biochemical reaction of the kind in which the materials to be treated are introduced into at least one reactor where they undergo the action of 10 microorganisms, such as bacterial colonies, which produce an anaerobic fermentation for the purpose of producing biogas, causing the materials to continuously circulate between a main inlet and an outlet. located at the two ends of the reactor, the material passing during a hydraulic retention time corresponding to the resting time required for the average treatment of the materials included in the feed, this method being characterized by comprising: 20. continuously allowing the materials to circulate in the reactor longitudinally and along a non-line err, concave and especially curved web, - performing at least one removal operation of at least one flow of material in a suitable portion of the web to reintroduce it upstream to induce * at least a partial recycling of the treated materials which are specific to a dominant reaction zone, the point of entry and the point of discharge of the recycled materials being mainly at the point of entry or at the point of execution of the virtual volume defining said zone within the reactor, - controlling the rate of recirculation in said zone to adjust. the mean retention time of the material in this zone after the time of reproduction of the colonies by specific microorganisms in this zone, and to control conditions specific to a dominant reaction in each of the subsequent zones by regularly continuing with to take physical and / or chemical 5 and / or biology precautions adapted to allow the determination of the state of the material and the conditions of development of the dominant reaction in each zone. A method according to claim 1, characterized in that the recirculation of the materials between the outlet of a working zone specific to a dominant reaction and the inlet of this zone is regulated to allow access to graft of fresh material into the zone of colonies of microorganisms. which are specific to the dominant reaction 15. zone. Method according to one of claims 1 or 2, characterized in that the method further comprises limiting the gas atmosphere prevailing over each zone by placing separation means such as an upper transverse wall at the locations corresponding to the outlet. of a dominant reaction zone and to the inlet of a subsequent zone corresponding to another dominant reaction, thus isolating the gas atmospheres located above each zone. Process according to one of claims 1-3, characterized in that it further comprises recirculating biogas tapped from the gas atmosphere into a zone of the material which is treated in a preceding or subsequent zone, the biogas serving as a chemical or biochemical substance in the evolution of the dominant reaction. Process according to one of Claims 1 to 4, characterized in that within a small through-section and a large path length corresponding to the movement path DK 168480 B1 26 for the treated material, four subsequent zones are defined, each corresponding to a dominant reaction. , namely: a) a first zone designated for a hydrolysis process and located between the main inlet and a first intermediate inlet; b) a second zone downstream along the path of the treated material and destined for an acidogenesis process, which second zone lies between the first intermediate inlet and a second intermediate inlet; c) a third zone again downstream along the path of the treated material and destined for an acetogenesis process, said third zone being between the second intermediate inlet and a third intermediate inlet; (d) a fourth downstream zone corresponding to a methanogenesis process, said zone being between the third intermediate inlet and the effluent material inlet, and the method comprising controlling the feed conditions, the recirculation conditions, the temper ature conditions, and 25 re-injection ratios of biogas in each zone as a function of the dominant reaction in that zone. Process according to one of Claims 1 to 4, characterized in that three successive zones are generated in the path of the treated material in the passage and that these three zones correspond to the following dominant reactions: a) a first zone determined for hydrolysis; B) another zone intended for reactions of an acidogenesis and an acetogenesis; and finally c) a final zone intended for the reaction of a methanogenesis; and that the method comprises controlling the feed ratios, recirculation ratios, temperature ratios and re-injection ratios of biogas in each zone as a function of the dominant reaction in that zone. Process according to one of Claims 1 to 4, characterized in that two subsequent zones are defined in the path of the material, namely: a) a first zone intended for reactions of hydrolysis, aci-dogenesis and acetogenesis; and b) and another zone intended for the reaction of the dominant methanogenesis. Process according to one of Claims 1 to 7, characterized in that physical and / or chemical and / or biological measurements, in particular measurements such as pH, temperature, viscosity of the material, are regularly performed to control the conditions specific to a dominant reaction. in feed, the composition and flow rate of the produced bi-25 ash in each zone to specifically influence the parameters of the output of the dominant reactions in each zone to determine the state of the material and the progress of the dominant reaction in each zone and and as a function of the evolution of the reaction, thereby optimizing the execution conditions of the dominant reaction in each zone. Process according to one of claims 1-8, characterized in that intermediate metabolites or reagents adapted to bacterial flora and the dominant reaction occurring in this zone are introduced into the mixture in the mass of materials to be treated, these metabolites. - DK 168480 B1 28 liters and reagents are selected from the family comprising: (a) glucose-containing products introduced into the acidogenesis zone; B) acetate-containing materials introduced into the methanogenesis zone; c) oxygen, pure or mixed (especially in the form of air) introduced into the initial zone of hydrolysis for the purpose of causing an aerobic predation; and d) hydrogen, pure or in admixture, introduced the zone of methanogenesis for the purpose of causing the reduction of CO 2 and converting it to methane. 10. Installations for treating organic matter in solid or dough form and under the influence of microorganisms such as bacterial colonies, in particular for the production of biogas, the plant being of the kind consisting of a closed container forming a reactor which in it one end is provided with a main inlet for the material to be treated, and at the other end an outlet for the dissolved effluent material, characterized in that the container is formed with a small constant cross-section relative to its length, and in a plan view of a web as a ring segment is connected to an insert (39), an embodiment (40) and has means for collecting and introducing materials (33, 34, 35, 36, 37, 38) or biogas (70, 71) , 72, 73, 74, 75, 76, 77) to a disengaged central portion located in the middle of said ring segment constituting a technical area (23, 32, 32 ') comprising means for controlling and directing the treatment in the container at its various points. Plant according to claim 10, characterized in that the plant along its path comprises said means for removing material (33, 35, 37) from the flow of material in the passage. in the plant and said means for introducing material (34, 36, 38) into the flow of material in the passage, which means are placed on the concave wall in the container of the plant. Installation according to claim 10 or 11, characterized in that the reactor on its upper part and starting from its wall and forming roof comprises separate means such as substantially vertical transverse partitions (41) extending into the material of the reactor. course of the reaction, these partitions being adapted to divide the free space above the doughy material along the way in the reactor, delimiting each other independent air space, each volume being connected to a central unit (32) intended to separately collect the samples taken in these gaseous phases corresponding to each of the volumes and to a particular composition. Installation according to one of claims 10 to 12, characterized in that each of the transverse walls insulating the gaseous phases of the different zones is located immediately at each of the means of transport (33, 34, 35, 36, 37 38. corresponding to an intermediate inlet and therefore delimiting reaction zones (42, 43, 44, 45), and that each air-25 volume in each zone is separated from the air volume of the other zones, where a different dominant biochemical reaction takes place . Installation according to one of claims 10-13, characterized in that the reactor has a capacity whose volume is defined by at least two inclined side walls (2, 2 ') which meet at the bottom of the reactor and form between themselves. upwardly extending compartments, wherein the upper edges (3, 3 ') of the two walls are substantially parallel, the walls at their ends being elongated by two transverse walls, a first wall carrying the main inlet of the material while the second transverse 30 DK 168480 B1 wall carries the outlet for the products in the form of effluent materials and the reactor comprises an upper wall forming a roof (15) which rests in a fluid-tight manner with its two side edges (12, 12 ') on top of the two upper edges (3, 3 ') of the said oblique side walls. Installation according to one of Claims 10 to 14, characterized in that the reactor is composed on one side of a trench dug into the ground, said trench having an upwardly open 10 in particular V- or U-shaped cross section, and that the trench walls are provided with surface elements defining the sloping side walls of the container (8, 8 ') and ensuring the tightness of the space, and the container on the other side above the gutter comprises roof elements (15, 15'), each of the opposite edges of the roof elements. resting on the upper edges of said surface elements and being joined to a shoulder formed by support means (10, 10 ') / fixed to the surface elements of the gutter and comprising the roof elements (15, 15') interposed between two impact members, sealing means, and that the end roof elements at each end of the container comprise a wall shaped so that they can be joined together with a transverse wall (17) provided with a flange (18) in the gutter to seal each end. Installation according to claim 10, characterized in that the technical area (23, 32, 32 ') comprises means for storing, preparing, introducing and recirculating the treated materials or biogas, means for circulating and regulating the supply of the heating fluids, means for analyzing the material removed from the reactor and for measuring the parameters in the treated materials and in the biogas produced, means for storing and introducing new reagents or metabolites, and where the technical field relates to means for treating and removing fa -35 materials and / or liquids such as radial conduits at various locations on the reactor and where the technical area is located at the same distance from these sites on the reactor. An installation according to one of claims 10-16, characterized in that the annular reactor comprises several injection pipelines (23 ', 51, 52) arranged at least along one of its inclined side walls and intended to disperse injected gas. from the technical area and from place to place at the bottom of the container, the pipelines appearing from a gas source located in the central technical area. Installation according to one of claims 10-17, characterized in that the central area comprises means for directing the material from the central zone towards each of the inlets, respectively the main inlet or an intermediate inlet in the reactor, for the purpose of allowing supply and recirculation in the reactor in its various zones, and the plant also comprises means for controlling the material removed from the reactor at each intake for the purpose of recycling the material re-introduced via an intermediate upstream feed port.