WO2014101915A1

WO2014101915A1 - Method and device for producing regenerative energy from biomass

Info

Publication number: WO2014101915A1
Application number: PCT/DE2013/100393
Authority: WO
Inventors: Thomas Reichhart
Original assignee: Thomas Reichhart
Priority date: 2012-12-27
Filing date: 2013-11-20
Publication date: 2014-07-03
Also published as: EP2938729A1; DE102012113119A1

Abstract

The invention relates to a method for producing regenerative energy by fermentation of biomass in at least one fermenter (6), wherein the biomass is subjected to a pretreatment before being fed to the fermenter (6), the method comprising the following steps: - feeding the biomass to a closed reactor (5); - pretreating the biomass under the action of heat and pressure in at least one sub-process of the hydrothermal carbonization in the reactor (5); - feeding the pretreated biomass to the fermenter (6); and - fermentation of the pretreated biomass for the production of biogas.

Description

Method and device for generating regenerative energy from biomass

The invention relates to a method for generating regenerative energy

Biomass according to the preamble of patent claim 1 and a device for generating regenerative energy from biomass according to the preamble of

Patent claim 10.

Under biomass in the context of the invention are all renewable

Raw materials, i. vegetable biomass and derived therefrom animal biomass and their metabolites understood, so for example, green waste, wood chips, plant and plant residues, straw, silage, agricultural residues, Papierbzw. Sewage sludge etc. Processes for the production of regenerative energy from biomass are already well known. In particular, methods for producing biogas, i. a methane-containing gas mixture by fermentation of biomass known. Here, biomass introduced into a biomass feed is fed via a conveyor to a fermenter, in which the fermentation of the biomass used takes place under anaerobic conditions. In most cases, after the at least one fermenter a Nachgärer provided, which is airtight and biomass taken in addition to the further fermentation or residual fermentation from the fermenter used as a storage container for the resulting biogas. The biogas obtained from the fermentation process is preferably used in a combined heat and power plant to generate electrical energy and heat energy. In another application, the biogas obtained from the fermentation process is fed into the natural gas grid after treatment.

Furthermore, methods for hydrothermal are already known from the prior art

Carbonization of biomass known. Hydrothermal carbonisation is a thermochemical process that simulates the natural production process of lignite. This biomass is used as starting material in a reactor dehydrated and carbonated at a pressure in the range between 10 bar and 55 bar and temperatures in the range between 1 50 ° C and 270 ° C, wherein the

Reactor outlet then a coal slurry can be removed. In this

Coal sludge contains carbon particles which can be removed from coal sludge by a drying and / or dewatering process. These coal particles obtained after the drying and / or dewatering process produce a coal dust containing almost all of the carbon of the processed biomass and having a calorific value substantially equal to the calorific value of fossil brown coal.

In order to increase the biogas yield in biogas plants, it is also known to pretreat the biomass used and thereby to comminute its structure. For this purpose, in particular devices are used which mechanically break the biomass, such as hammer mills, Hächsler, extruder or the like. It is also known that the biomass to be fermented before the fermentation process or after the

Fermentation resulting under fermentation process under the influence of temperature too

sanitize to kill the germs contained in the biomass or digestate and thus to prevent the health risk to humans by spreading the digestate on agricultural land and thus the entry of the germs contained in the fermentation residues in the food chain. The digestate, for example, at a temperature of 70 ° C for at least 1 hour.

sanitized.

A disadvantage of the known pretreatment of the biomass is that the

Structural crushing is insufficient and thus the biogas yield can only be increased slightly. Furthermore, the biomass pretreatment or the sanitation of the fermentation residues requires considerable energy, so that the energy balance of the entire plant is deteriorated. Based on this, it is an object of the invention, a method or a

To provide apparatus for generating renewable energy from biomass, which overcomes the aforementioned disadvantages. The task is based on the The preambles of the independent claims 1 and 1 0 each solved by the characterizing features.

The essential aspect of the process according to the invention for the production of regenerative energy by fermentation of biomass in at least one fermenter, in which the biomass is subjected to a pretreatment before being fed to the fermenter, is that the biomass is fed to a closed reactor, the biomass subsequently is pretreated under the action of heat and pressure in at least one sub-process of the hydrothermal carbonization in the reactor, the resulting pretreated biomass is removed from the reactor and fed to the at least one fermenter and then the fermentation of the pretreated biomass to produce biogas. The pretreatment of the biomass in the reactor by at least one sub-process of the hydrothermal carbonization has the decisive advantage that a

Structural reduction of the biomass without mechanical effort, for example by Hächsler, hammer mills, extruders or the like is required. During the process of hydrothermal carbonation several run

Reaction mechanisms, in particular the reaction mechanisms of hydrolysis, dehydration and aromatization. The process of hydrolysis results in the pulping of the cellulose contained in the biomass, whereby the gas yield can be considerably increased. Further, by the reaction mechanism of dehydration, water molecules are split off, so that water, hereinafter referred to as dehydrated water, is released. This cleavage of dehydrated water prior to introduction into the fermenter and preferably removal of this

Dehydratwassers separated from the pretreated biomass from the reactor causes the subsequently introduced into the fermenter, pretreated biomass has an increased dry matter. This will turn the

Gas yield significantly increased in biogas production. Furthermore, by the pretreatment of the biomass by the at least one sub-process of

hydrothermal carbonization the plasticity or structural viscosity of the

Fermenter contained biomass or contained in the fermenter biomass Reduced liquid mixture compared to conventional structurally comminuted biomass, so that the necessary stirring energy in the fermenter is reduced.

In a particularly preferred embodiment, the biomass is pretreated in the reactor over a period of 0.5 hours to 8 hours. Depending on the residence time of the biomass in the reactor, the cumulative process of hydrothermal carbonization will undergo a variable subrange, i. the reaction mechanisms of hydrolysis, dehydration and aromatization that take place in the hydrothermal carbonization are carried out depending on the residence time. Preferred is a refueling time within the reactor which causes complete or mostly complete cellulosic digestion by hydrolysis. Further preferably, the residence time in the reactor is such that at least partial dehydration of the biomass occurs. As a result, as already mentioned above, after separation of the resulting dehydrated water, the dry mass of the biomass introduced in the fermenter can be increased.

In a preferred embodiment, the pretreatment of the biomass is carried out at a temperature between 100 ° C and 270 ° C. Particularly preferred

Temperatures in the range between 1 50 ° C and 250 ° C, in particular temperatures between 1 80 ° C and 240 ° C. Within these temperature ranges, a pretreatment of the biomass by at least one sub-process of

hydrothermal carbonation. Advantageously, within this

Temperature range also a sanitation of the biomass, i. a killing of germs contained in the biomass. This can be a contribution of germs in the food chain by spreading the after the fermentation process

resulting fermentation residues on agricultural land can be effectively avoided.

In a further preferred embodiment, the pretreatment of the biomass takes place within the reactor at pressures between 5 bar and 55 bar, preferably in the range between 10 bar and 35 bar. In the mentioned pressure ranges can optimal structural comminution of the biomass by the at least one sub-process of the hydrothermal carbonization carried out.

In a further preferred embodiment, the

Pretreatment dehydration of the biomass, wherein the water formed during dehydration is removed from the reactor separately from the at least partially pretreated biomass. In the reaction mechanism of

Dehydration, which is a sub-process of hydrothermal carbonation, splits off water molecules from the biomass. The resulting dehydrated water rises within the reactor and thus forms an upper layer in the reactor, so that when providing a removal device on the reactor,

For example, in the upper half of the reactor, the dehydrated water can be removed separately from the at least partially pretreated biomass. By cleavage of dehydrated water s, the dry matter of the pretreated, then transferred to the fermenter biomass is increased, causing the

Biogas yield per m ³ fermenter volume during the fermentation of the pretreated biomass is significantly increased.

In a preferred embodiment, the reactor by a passage of gases, gas mixtures and / or vapors by at least one in the

Heat exchanger provided in the reactor interior or heated

temperature stabilized. At the beginning of the process, it is necessary, the reactor to a

desired temperature, in particular to a temperature between 100 ° C and 250 ° C to heat. Although the process of hydrothermal carbonization is an exothermic reaction process, i. Reaction energy is released in the form of heat, it may be necessary depending on different process parameters, a temperature stabilization of the reactor and thus a

To achieve process control. As a result, the pretreatment process can be operated in a desired process window with desired process parameters.

Preferably, the heating and / or temperature stabilization of the reactor by a passage of flue gases through the heat exchanger, wherein the Flue gases during combustion of the biogas to generate electrical energy arise. The heat exchanger is preferably a tube heat exchanger with a plurality of vertically arranged tube elements, which are surrounded by the biomass or the biomass-liquid mixture. Preferably, a biogas plant is operated in conjunction with a downstream B hlockheiz kr aftwerk in which by combustion of the biogas produced electrical energy or heat energy is generated. Through the passage of the combustion process in the

Combined heat and power plant arising flue gases through the heat exchanger, the waste heat contained in the flue gas can be used for heating and / or temperature stabilization of the reactor.

Preferably, water is used for cooling in the cogeneration plant, whereby preferably also a use of the heat energy contained in the cooling water is provided, in which the heat energy contained in the cooling water is withdrawn and removed for further use. As a result, legal requirements, in particular requirements of the Renewable Energy Sources Act (EEG) can be met. To control the temperature of the gas or vapor passed through the heat exchanger, mixing devices may be provided which have a controlled flow

Adding a desired amount of fresh or cold air to the flue gas or steam cause. The admixture can be used to control the temperature of the gas or vapor passed through the heat exchanger and thus to effect a temperature control of the reactor.

Preferably, the introduction of biomass into the reactor, the removal of pretreated biomass from the reactor and the subsequent process of fermentation of the biomass is continuous or quasi-continuous in one

Completion process carried out, wherein the supply of biomass into the reactor or the removal of pretreated biomass from the reactor in short successive time intervals, for example, intervals of 5 min. To 30 min., I. intermittently. Likewise, a continuous supply of biomass into the reactor or a continuous removal of

pretreated biomass possible. This will be compared to the total in the Reactor interior existing biomass volume lower volume of

Biomass respectively supplied or discharged on pretreated biomass, so that the residence time within the reactor is substantially greater than the introduction or removal cycles.

In a preferred embodiment, the biomass is heated prior to introduction into the reactor in a preheater. The preheating of the biomass causes the reaction inside the reactor interior reaction mechanisms are not or only slightly disturbed by the continuous or quasi-continuous introduction of new biomass, since the preheating of the biomass, the pressure and temperature fluctuations in the reactor interior are minimized. This is particularly the case when the biomass is preheated to a temperature equal to or approximately equal to the temperature in the reactor interior. In a preferred embodiment, the heating of the biomass takes place by removal of dehydration resulting hydrate water in the liquid state from the reactor, by direct supply of dehydrated water to the preheater and mixing the dehydrated water with the biomass within the preheater. Due to the fact that the water in the liquid state in comparison to steam a larger amount of

Having heat energy per unit volume, is supplied by the removal of a defined volume of dehydrated water in the liquid state from the reactor, a larger amount of heat energy of the preheater than in the removal of the same volume of water vapor. Thus, in order to obtain a specific heat input into the biomass, a smaller volume of dehydrated water than the use of water vapor must be removed so that the reaction mechanisms in the interior of the reactor are only slightly impaired. Especially when using biomass with a high

Dry content is achieved by mixing the biomass with the dehydrated water an improved, more uniform preheating of the biomass compared to conventionally used heat exchanger systems, since the heat exchangers when using relatively dry biomass, in particular biomass with a Dry content greater than 20%, tend to encrustation on the heat transfer surfaces and thereby decreases the efficiency of the heat exchanger.

In a further preferred embodiment, prior to introducing the biomass into the reactor, the pressure in the preheater is increased to a pressure at least equal to the pressure in the reactor. By such

Pressure increase in the preheater can be omitted a pumping device, which causes a transfer of preheated biomass from the preheater in the reactor interior. Rather, a carryover can take place which is effected solely by the gravitational effect on the biomass or the mixture of biomass and dehydrated water, i. the biomass or biomass mixture is allowed to fall from the preheating arranged above the reactor in the reactor interior. Alternatively, it is possible to increase the pressure in the preheating device via the pressure in the interior of the reactor so that a carryover caused by the overpressure takes place from the preheating device into the interior of the reactor. Due to such overpressure in the

Preheating a blockage of the outlet of the preheater or the feed opening of the reactor is effectively avoided. According to a further aspect, the invention relates to a device for generating regenerative energy by fermentation of biomass in at least one fermenter, wherein before the at least one fermenter, a reactor is provided, which for pretreatment of the biomass by at least one

Sub-process of hydrothermal carbonation, i. Loading the biomass is formed with pressure and temperature.

Particularly preferably, at least part of the inner wall of the reactor and / or the entire inner wall of the reactor has a coating of a highly lubricious material. This highly lubricious material may in particular be a polytetrafluoroethylene (PTFE), with a coating having a layer thickness of from 1 to 20 μm being preferred. The coating offers the decisive advantage that the lubricity of the process intermediates or end products the reactor wall is decisively improved, so that even with prolonged continuous use of the reactor no process is negative

form affecting deposits. In particular, the heat exchanger, in particular the tube elements of the heat exchanger with such a

Be provided coating of a highly lubricious material. Particularly preferred is a condensation water resistant and a high

Temperature differences on the tubular elements of the heat exchanger resistant polytetrafluoroethylene used. Under the direct supply of dehydration water for preheating a supply, for example by means of pipes without further

Devices, in particular evaporator for relaxing the water, understood. Under direct feed, however, is also a pipeline or a

Pipe system comprising at least one barrier means, in particular to understand a valve for closing the preheater and / or the reactor.

Under dehydration water according to the invention is present in the reactor

Liquid understood that contained by the biomass or admixed liquid and / or formed during the dehydration process of the biomass split off water molecules.

The term "substantially" in the context of the invention means deviations from the exact value by +/- 10%, preferably by +/- 5% and / or

Deviations in the form of changes that are insignificant for the function.

Further developments, advantages and applications of the invention will become apparent from the following description of the embodiment and from the figures. All are described and / or illustrated

Features alone or in any combination in principle subject of the invention, regardless of their summary in the claims or their dependency. Also, the content of the claims is made an integral part of the description. The invention will be explained in more detail using an exemplary embodiment in conjunction with the figures. 1 shows by way of example a plant according to the invention for the production of regenerative

Energy from biomass in a schematic presen- tation;

Fig. 2 shows an example of the graphical representation of in a batch experiment

determined gas yield over the residence time of the biomass in the fermenter using biomass pretreated according to the invention; and FIG. 3 shows, by way of example, a plant according to the invention for producing regenerative plants

Energy from biomass with a preheating device in one

schematic representation.

In Figure 1, the reference numeral 1 is an inventive system for

Production of renewable energy from biomass shown. The plant 1 has a biomass application 2, at which in particular dry or substantially dry biomass with a dry content> 30% is introduced and controlled by a conveyor 3 or intermittently fed to the reactor 5. The conveyor 3 may in this case be a screw conveyor, a conveyor belt, a push floor conveyor or biomass with a high water content and a pump.

The reactor 5 is formed by a pressure-resistant container which surrounds or delimits a reactor interior 5.1 through its container walls. For filling the interior of the reactor with biomass, the reactor 5 has an inlet 5.2, via which the biomass passes into the reactor interior 5.1. Preferably, the inlet 5.2 is provided at the top of the reactor 5. The biomass fed to the reactor 5 is pretreated after introduction under the action of pressure and temperature in a thermochemical process. The pressure in the interior of the reactor 5 is set to a value between 5 bar and 35 bar, preferably between 10 bar and 25 bar. The temperature of the biomass in the reactor interior, values between 1 00 ° C and 250 ° C,

preferably from 1 50 ° C to 250 ° C, more preferably from 1 80 ° C to 240 ° C.

When introducing the biomass into the reactor 5 is preferably a

Mixing the same with befindlichem in the reactor 5 water or biomass liquid mixture. The resulting aqueous biomass mixture preferably has a pH in the range of 3 to 6. Under these

Within the reactor 5, the process conditions include the process of hydrothermal carbonization, in which the process stages hydrolysis,

Dehydration and aromatization coal slurry containing a coal particles formed. Preferably, however, the process of hydrothermal carbonization is not completely run through, but the process is terminated after a period of time between 0.5 hours and 5 hours and the biomass thus pretreated is removed from the reactor interior 5.1 via an outlet 5.3 of the reactor 5. By at least a Tei lprozess the hydrothermal carbonization, which is run through during the Verwei ldauer the biomass in the reactor, a splitting of the molecular structure of the biomass. In particular, the cellulose contained in the biomass is isomerized by a hydrolysis process and in

Glucose or fructose split. Preferably, the introduction of the biomass or the application of the biomass from the reactor 5 is carried out continuously or quasi-continuously in a continuous process, which is maintained by the Einbri ning or application of 5.1 in the reactor interior vol-forming thermochemical process, i. the supplied amount of biomass or the discharged amount of pretreated biomass is dimensioned in comparison to the remaining in the reactor interior 5.1 amount of biomass that change the process parameters within the reactor 5 only insignificantly, so that the vol leaching Tei lprozesse the hydrothermal Carbonation in the

Maintain unchanged.

In the interior of the reactor 5.1, preference is given to dehydration which takes place during the hydrothermal carbonization as a reaction mechanism

Splits off water molecules from the biomass, ie within the reactor 5 takes place a separation of water. This separated water rises in the reactor 5 upwards and is preferably removed separately from the pretreated biomass at a discharge opening 5.4 the reactor interior 5.1. As a result, the dry matter of the pretreated, subsequently fermented biomass is advantageously increased substantially.

The pretreated biomass is removed at the outlet 5.3, as already mentioned above, and fed to a fermenter 6 of a biogas plant. In fermenter 6, at least partial fermentation of the biomass takes place under anaerobic conditions

Conditions whereby the fermentation process produces methane-containing biogas.

Preferably, the fermentation process within the fermenter 6 as

operated continuous fermentation process, wherein the fermenter 6 continuously or at regular intervals pre-treated biomass from the reactor 5 is supplied and the at least partially fermented biomass or its digestate is supplied to the post-fermenter 7 together with the biogas produced in the fermenter 6. The secondary fermenter 7 serves for a residual fermentation of the biomass or digestate of the biomass, on the other hand as gas storage for the biogas produced within the post-fermenter 7 or in the fermenter 6.

The essential Vortei l the pretreatment of the biomass in the reactor 5 by at least one sub-process of hydrothermal carbonization is that the residence time of the biomass within the fermenter 6 to achieve a certain biogas yield can be significantly reduced or the biogas yield at a constant residence time in the fermenter. 6 or in the post-fermenter 7 can be significantly increased.

FIG. 2 shows a diagram in which the gas yield or the gas yield in NL / kg oTM (net liter per kilogram of organic dry matter) is plotted over time. Whole plant silage of the cereal Tritikale was in a

Retention of 1 hour pretreated in the reactor 5, for example at a temperature of 200 ° C and a pressure of 1 6 bar. By the

Pretreatment can significantly increase the gas yield. When using whole crop silage of the cereal Tritikale without pretreatment by means of a sub-process of the hydrothermal carbonization, the gas yield after 31 days of residence in the fermenter / Nachgärer only 41 9 NL / kg oTM, i. the gas yield during pretreatment by means of a sub-process of hydrothermal

Carbonation is already increased by more than 20% after 24 days of residence in the fermenter / postgrader. Furthermore, the length of stay within the

Fermenters / Nachgärers at a desired solid gas yield through the

Pretreatment according to the invention are significantly reduced, since the o.g. Value of gas yield at pretreatment of biomass already at 12 days

Residence time in the fermenter / secondary fermenter is reached.

The system 1 also has, in a conventional manner, a Gärresteend bearing 8, in which the digestate from the post-fermenter 7 are introduced.

The combustible gases produced in the fermenter or in the post-fermenter 7 are preferably taken from the gas reservoir provided in the region of the secondary fermenter and fed to a combined heat and power plant 9, by which electric current and heat are generated upon combustion of the combustible gas generated within the biogas plant. The residual heat utilization of the cogeneration unit 9 is carried out by passage of the flue gas produced during combustion through a provided in the interior of the reactor 5 heat exchanger 10, the

Passage of the flue gases is formed.

As shown in Figure 3, the heat exchanger 10 is formed as a tube heat exchanger and has a plurality of, preferably vertically arranged pipe element 10.1, which are connected to the flue gas line 9.1 connected to the cogeneration unit 9 and thus flows through the flue gas. As a result, heating of the biomass contained in the reactor interior 5.1 or the biomass liquid mixture is effected. Preferably, a mixing device 9.2 is provided in the flue gas line 9.1 between the cogeneration unit 9 and the reactor 5, which is a controlled

Admixing a desired amount of cold air or fresh air to the flue gas allows. As a result, the flue gas temperature or the heat input into the reactor 5 is controlled via the heat exchanger 10. The required heat input in the reactor 5 depends largely on the biomass used or the dry fraction of this biomass, wherein biomass with a higher dry content requires less heat input, as biomass with a low dry content. By the controlled supply of cold air or fresh air to the flue gas can be taken into account the respective required heat demand depending on the processed biomass. In addition, a control of the temperature of the guided through the heat exchanger 10 flue gases in dependence on the respective

Process conditions possible. Preferably, a residual heat utilization of the amount of heat contained in the flue gas> 50% is carried out by the passage of the flue gas through the heat exchanger 10, so that by a further provided

Residual heat in the cooling water circuit of the combined heat and power plant, in which at least 10% of the waste heat generated in the cogeneration unit 9 is used, the legally required limit of at least 60% of the residual heat is reached. The residual heat utilization of the cooling water is preferably carried out by the heat exchanger 1 1.

In Figure 3, the inventive system 1 is shown in a higher level of detail. The plant 1 has a preheating device 12 arranged between the biomass feed 2 and the reactor 5, to which the biomass feed introduced at the biomass feed 2 is fed via the conveyor 3. The

Preheating device 12 is preferably a pressure-resistant, apart from supply and discharge lines, closed container, which serves to preheat the biomass prior to introduction into the reactor 5. It is preferably arranged above the reactor 5, in particular directly above the inlet 5.2. The preheating of the biomass has the advantage that the introduction of the biomass into the reactor 5, the temperature fluctuations are minimized within the reactor 5, and thereby the at least one sub-process of the hydrothermal carbonization within of the reactor 5 by the intermittent introduction of new biomass

is maintained.

The preheating of the biomass is preferably carried out by removal of

Liquid from the reactor 5, for example by means of the removal device 12.1. Preferably, water is separated from the biomass introduced into the reactor 5 by a dehydration process, so-called dehydrated water, which is supplied to the preheating device 12 via the removal device 12. Within the preheating 12 preferably takes place mixing of the dehydrated water with the biomass. This water has approximately the prevailing temperature in the reactor 5, i. preferably temperatures in the range of 100 ° C to 250 ° C and can be used optimally for heat input into the biomass to be heated due to its high specific mass. To remove the dehydrated water in the liquid state from the reactor 5 is an immediate fluid connection between the reactor 5 and the

Preheating device 12 is provided, via which the dehydrated water can be withdrawn from the reactor 5, preferably controlled by at least one valve. When supplying the dehydration water in the preheating 12, this is preferably closed pressure-tight, so that upon supply of the pressurized

Dehydratwassers the pressure inside the preheater 12 is increased. Preferably, the pressure within the preheater 12 is increased above the pressure prevailing in the reactor 5. This pressure increase can take place, for example, by means of a pressure generator or a pressure accumulator coupled to the pressure generator. After the increase in pressure in the preheater 12, the preheated biomass or the mixture of biomass and

Dehydrated water is fed via the inlet 5.2 to the reactor 5. In the event that prevails in the preheater 12, the same pressure as in the reactor 5, the biomass is introduced into the reactor 5 due to gravity. Preference is given to an increase in the pressure in the preheating 12 on the pressure in the reactor 5, so that clogging of the outlet of the preheater 12 and the

Feed opening 5.2 of the reactor 5 is effectively avoided. The invention has been described above by means of an embodiment. It is understood that numerous modifications and changes are possible without departing from the inventive concept.

LIST OF REFERENCE NUMBERS

1 plant

2 biomass task

3 conveyor

5 reactor

5.1 reactor interior

5.2 Inlet

5.3 outlet

5.4 removal opening

6 fermenters

7 After fermentation

8 fermentation residue storage

9 combined heat and power plant

9.1 flue gas line

9.2 mixing device

10 heat exchangers

10.1 pipe element

1 1 heat exchanger

12 preheating device

12.1 unloading device

25

Claims

claims

Process for the production of regenerative energy by fermentation of biomass in at least one fermenter (6), wherein the biomass is subjected to a pretreatment before being fed to the fermenter (6), characterized in that the process comprises the following steps:

- Supply of biomass to a closed reactor (5);

- pretreatment of the biomass under the action of heat and pressure in at least one partial process of the hydrothermal carbonization in the reactor (5);

- feeding the pretreated biomass to the fermenter (6); and

- Fermentation of pretreated biomass for the production of biogas.

A method according to claim 1, characterized in that the biomass is pretreated over a period of 0.5 hours to 5 hours.

Method according to claim 1 or 2, characterized in that the

Pre-treatment of the biomass is carried out at a temperature between 1 00 ° C and 270 ° C.

Method according to one of the preceding claims, characterized

characterized in that the pretreatment of the biomass is carried out at pressures between 5 bar and 55 bar.

Method according to one of the preceding claims, characterized

characterized in that by the pretreatment, a dehydration of the biomass is carried out, wherein the water formed during the dehydration is taken separately from the pretreated biomass from the reactor.

6. The method according to any one of the preceding claims, characterized

characterized in that the reactor is heated by a passage of gases and / or water vapor through at least one in the reactor interior (5.1) provided heat exchanger (10) and / or temperature stabilized.

7. The method according to claim 6, characterized in that the heating and / or temperature stabilization by a passage of flue gases through the heat exchanger (10), wherein the flue gases in the

Combustion of biogas to generate electrical energy arise.

8. The method according to any one of the preceding claims, characterized

characterized in that the biomass is heated in a preheater (12) prior to introduction into the reactor (5).

9. The method according to claim 8, characterized in that the heating of the biomass by removing arising by dehydration

Dehydrated water in the liquid state from the reactor (5), by direct supply of the dehydrated water to the preheater (12) and

Mixing the dehydration water with the biomass in the

Preheating device (12) takes place.

10. A device for generating regenerative energy by fermentation of biomass in at least one fermenter (6), characterized in that in front of the at least one fermenter (6), a reactor (5) is provided for pretreatment of the biomass by at least one sub-process of hydrothermal carbonation, ie Loading the biomass is formed with pressure and temperature.

1 1 .Vorrichtung according to claim 10, characterized in that in the interior of the reactor (5), a heat exchanger (10) is provided, which is designed for the passage of gases and / or vapors.

12. The apparatus of claim 10 or 1 1, characterized in that in front of the reactor (5) is provided a preheating device (12) for heating the biomass prior to introduction into the reactor (5).

1 3. Device according to one of claims 10 to 12, characterized in that the reactor (5) on at least a part of the inner surface of the

Reactor wall has a coating that prevents adhesion of the biomass.

14. Device according to one of claims 1 1 to 1 3, characterized in that the heat exchanger (12) has a coating which prevents adhesion of the biomass.

1 5. Device according to one of claims 1 3 to 14, characterized in that the coating is at least one layer of polytetrafluoroethylene (PTFE).