DE102009032122A1 - Generating energy from a biomass, preferably producing biogas from the biomass, comprises feeding reactants, converting reactants into products, and discharging products, where method is carried out according to memory batch process - Google Patents

Abstract

Generating energy from a biomass, preferably producing biogas from the biomass, comprises: feeding reactants, preferably the biomass; converting reactants into products; and discharging the products, where the method is carried out according to a memory batch process, and the steps of feeding, converting and discharging the solid and liquid products are carried out at least spatially separated, and in which the gaseous products are removed in a quasi-continuous process at least during two of the above steps. Independent claims are also included for: (1) a device (1), preferably a bioreactor or a fermenter for carrying out the method, comprising at least one feeding device (2), at least one discharging device (3), and a fermenter space (4) coupled with the feeding device and the discharging device for receiving and converting the biomass, where the fermenter space, the feeding device and/or the discharging device are formed at least in pairs, which are moving relative to each other; and (2) a biogas plant (10) provided with the device.

Description

The The invention relates to a method for obtaining energy from biomass, in particular for the production of biogas from biomass, according to the preamble of claim 1

Further the invention relates to a device for energy production Biomass, in particular a bioreactor or fermenter for production of biogas from biomass, according to the generic term of claim 4.

moreover the invention relates to a biogas plant for energy and / or Energy supply from biomass, according to the preamble of the claim 9th

Known are biogas plants for the conversion of residues from sewage treatment plants, for liquid manure conversion or for the conversion of cultivated energy plants. These plants are large-scale Nature and require a minimum use according to their interpretation Biomass of 200 tons / year and more to be converted. That with the Biogas plants according to the state Biogas produced by technology serves to drive engines that turn the energy they generate into electrical and thermal Feed nets.

Out The prior art is for the extraction of energy from biomass, a so-called fed-batch process or a fed-batch process known.

Of the Fed-batch process comes mainly used in biotechnology and process engineering. in this connection is the production with a targeted control of educt supply the products optimized to disadvantages, which in a direct Addition of a maximum necessary amount of reactants may occur too avoid. In the fed-batch process it is a chemical-biological process.

in this connection all processes in a container expire. There is a controller and control of the degradation processes by the microorganisms in the foreground. A first step in the fed-batch process is to create a basic substance (Fertile soil) for the later To generate processes. The fed-batch process is predominantly used the process control. In another step of the fed-batch process no further substrate is supplied. The residence time in this Step is not predetermined; The step serves to reduce the educts. Here you can Fluctuations in gas evolution occur.

Of the Invention is based on the object, an apparatus and a method for energy production from biomass, in particular for the production of Biogas from biomass, which overcome the disadvantages and in particular a continuous mode of operation with a simple, as possible fluctuation-free process control realize.

Further the invention has for its object to provide a biogas plant for Generating energy and / or energy from biomass which is simple and continuous gas evolution with simple process control realized.

According to the invention this is through the objects with the features of claim 1, of patent claim 4 and claim 9. Advantageous developments can be found in the dependent claims.

The inventive method for energy production from biomass, in particular for the production of Biogas from biomass, comprising the steps of: supplying reactants, in particular Biomass, converting the starting materials into products and discharging the Products, characterized in that the method according to a Memory batch process is performed, in which the steps Respectively, Transform and remove the solid and liquid Products at least spatially carried out separately and in which the gaseous Products in the sense of a quasi-continuous process during at least two of the aforementioned steps are discharged.

In an embodiment the method according to the invention is provided that feeding temporally parallel to a discharge and / or a conversion is performed.

In a further embodiment of the invention, it is provided that the step of supplying educts for supplying unfermented biomass and supplying a fermented biomass residue (fermentation restes) from a downstream step to start a fermentation process.

The inventive device for energy production from biomass, in particular a bioreactor or Fermenter for the production of biogas from biomass, comprising at least a feeder, at least a discharge device and one with the feeder and the discharge device coupled fermenter room for receiving and converting biomass, is characterized in that the fermenter space, the feeder and / or the discharge device at least in pairs are designed to be movable relative to each other.

at a further embodiment The present invention provides that the fermenter room comprises at least three chambers, each optionally by a relative movement of fermenter room, feeder and / or discharge device to each other with the feeder and / or the discharge device can be coupled.

In yet another embodiment The present invention provides that the fermenter room, the feeder and / or the discharge device formed rotatably and / or translationally to each other movable are.

In a further embodiment the invention provides that at least two of the chambers of the Fermenterraums in their upper regions gas-conducting in conjunction stand. This can, for example, by a vaulting the upper chamber areas common room or else by a wired connection be realized. This ensures that that the biogas produced in the various chambers is combined dissipated can be.

One embodiment The device also provides that the chambers are arranged in such a way are that when one of the chambers is coupled to the feeder, another of the chambers is coupled to the discharge device.

The Biogas plant according to the invention for energy production and / or energy supply from biomass characterized in that a device according to the invention is provided.

One embodiment The present invention provides that a gas-tight system is provided.

Yet another embodiment The present invention provides that a monitoring and security system for at least a pressure in the fermenter, in particular in the fermenter room, and / or is provided in a gas storage.

Further sees another embodiment the present invention that a heating system for heating the Fermenter, especially the fermenter rooms, is provided.

Yet another embodiment The present invention provides that at least one interface intended for connection to a power grid and / or a water network is.

With the method according to the invention, the device according to the invention and the biogas plant according to the invention, in particular the following advantages are realized:
The simplified process management reduces the required own energy consumption of the system. The biogas production process takes place without mass transfer operations in each case in a fermenter chamber, whereby the number of necessary aggregates, such as transport devices between the chambers, control devices and the like, is reduced. Thus, the power requirement is reduced by reducing the number of units. Operating the system at a relatively low temperature level requires less heat for the fermenter heater. The plant according to the invention preferably has an integrated purification device, which makes use of biodegradation processes, so that no external, technical device for removing hydrogen sulfide is required. As a result, the expenditure on equipment is reduced and energy is saved. Biological hydrogen sulphide separation devices are used successfully, for example, in large biogas plants. Due to the compact design of the plant and the reduction of the peripheral fermenter aggregates, the space requirement of the plant is reduced. This is of particular importance since a preferred site is the home cellar. By an inventive redesign of the biogas plant a significant reduction in investment, operating and maintenance costs is achieved, which ge an economic operation of the plant guaranteed.

By a targeted control of educt supply can be the generation of Optimize products, as disadvantages, which in a direct addition the maximum necessary amount of educts can occur avoided become. With the memory batch process are a simple structure and a continuous evolution of gas realizable. The containers The memory batch process perform different tasks. The to be filled container serves for buffering, storage and fermentation of the substrate. A constant Gas yield from this container can be achieved by a quasi-continuous substrate feed. But this is not the control and control of the degradation processes by the microorganisms in the foreground but the homogenization biogas production. Ideally, the biogas plant can daily substrate supplied become. But it can even larger periods without Substrate feed to be bridged, without jeopardizing the whole process. It is also possible to load the plant with more substrate than the microorganisms currently implement. Again, the process of biogas production remains controllable.

in the Memory batch process does not require a ground substance - for example a breeding ground - for the later processes to create. The fermentation process is carried out during filling the repatriation of digestate started from another chamber. In the memory batch process becomes substrate with recycled digestate mixed and added to another chamber. By the regular substrate addition becomes a uniform gas output guaranteed.

At the Storage batch process has the substrate in the from the filling phase different phases at least the same residence time as in the Filling phase. Extend it in the memory batch process these other phases are the dwell time and guarantee the fermentation of the substrate. Thus, in the storage batch process, variations in gas evolution preferably kept low, resulting in frequent, preferably daily Substrate feed is achieved. Furthermore, the whole lingering Substrate as possible long in the fermenter. Therefore, several containers are operated offset to a longer one To guarantee residence time. Furthermore the inoculation of the fresh substrate is realized by a fermentation residue recycling, unless the fermenter is stirred shall be. This is done in the storage batch process by the digestate recirculation a rear container allows. The memory batch process needed across from less electricity used in a small-scale flow-through process and space. In addition, the storage batch process is especially for the small-scale Application designed.

The Drawings represent several embodiments of the invention and show in the figures:

1 schematically material, gas and heat flows of a biogas plant, which is operated according to a storage-batch process,

2 schematically the process principle of the storage batch process in a fermenter room with three chambers formed as containers in a first phase,

3 schematically the process principle of the storage-batch process in a fermenter room with three chambers formed as a container in a second phase and

4 schematically the process principle of the storage-batch process in a fermenter room with three chambers formed as containers in a third phase.

1 schematically shows material, gas and heat flows of a biogas plant 10 , which is operated according to a memory-batch method according to the invention. The biogas plant 10 includes a device 1 for energy production from biomass, according to the embodiment according to 1 designed as a bioreactor or a fermenter, for the production of biogas from biomass. The fermenter is according to 1 formed as a standing cylinder in three equal chambers 4a - 4c is undiluted, which together form the fermenter room. In the chambers 4a - 4c Different phases of the memory batch process expire. The chambers 4a - 4c are, as shown schematically by an arrow, relative to a feeder 2 and a discharge device 3 rotatable. An addition of a substrate S in the chambers 4a - 4c takes place according to the embodiment according to 1 from above and the removal from below. In the fermenter is a possibility for mixing of the substrate S in the chambers 4a - 4c intended. The device 1 includes at least one feeder 2 which in turn has different feed units. A first feeder unit 2a comprises a substrate-feeding unit, which preferably has a shredder. The task of the substrate S by the substrate application unit via a feed hopper, the substrate S in a mixing device 2 B leads. In the mixing device 2 B the substrate S is comminuted, the proportion of air in the substrate S is reduced and a recirculated digestate G is mixed in. Via a screw or a piston press, the mixture is the fermenter, more precisely the fermenter room 4 fed. The substrate S is then placed in a first chamber 4a filled, with the other chambers 4b . 4c stay tightly closed. Through a mechanism, the chambers can be 4a - 4c open and close. The mechanism ensures that even during the substrate task no air in the fermenter 1 enters or gas from the fermenter 1 exit. In particular, a device is provided before a fermenter task, which presses the remaining air from the substrate S. For example, the piston press can first compress the substrate S, before a flap to the fermenter 1 opens and the entry in the fermenter 1 he follows. To all chambers 4a - 4c to be able to feed with a press, this can be designed to be pivotable or the openings of the individual chambers 4a - 4c are arranged close to each other.

An evacuation unit 3 includes a first unit that serves as digestate recycle 3a is trained. The removal of the digestate G takes place on a fermenter bottom. By means of a screw, part of the digestate G becomes the first feed device, also referred to as the filling device 2a guided and mixed with the fresh substrate S, for example via the mixing device 2 B , the fermenter 1 again admitted.

A discharge of the non-recirculated digestate G also takes place at the bottom of the fermenter. First, the non-recycled digestate G enters one of the discharge device 3 included drainage facility 3b in which the digestate G is dewatered by means of a press, such as a screw press. The fermentation residue G is withdrawn via a discharge opening and, for example, filled into a bucket in order to reuse it. The resulting liquid F can be used as a liquid fertilizer, the solid digestate Gf is composted by mixing with structural material or disposed of, for example, a bio bin.

For a thorough mixing of the contents of the individual fermenter chambers 4 a mixing unit is provided to homogenize the digestate G before it is recycled or discharged. A thorough mixing takes place, for example via the screws for fermentation residue return by this takes the fermenter content below and feeds back up and thus circulating the digestate.

• • eine Einheit zur Füllstandsmessung in allen Behältern oder Kammern 4a–4c, die insbesondere analog ausgeführt ist und eine Ableseeinheit aufweist,
• • eine Einheit zur Volumenmessung und/oder Gewichtsmessung des dem Fermenter 1 zugeführten Substrats S und/oder des ausgetragenen und rückgeführten Gärrests G,
• • eine Einheit zur Messung der gebildeten Gasmenge,
• • eine Einheit zur Messung des Sauerstoffgehalts des Biogases,
• • eine Einheit zur Temperaturmessung im Fermenter 1,
• • eine Einheit zur Messung des Füllstands im Gasspeicher und
• • eine Einheit zur pH-Wert-Messung im Fermenter 1.

In the biogas plant type according to the embodiment according to 1 Different tasks have to be fulfilled. For the smooth operation of a process monitoring is preferably provided. In addition, additional measuring and control technology units are provided. The measurement units comprise the following units:

• • one unit for level measurement in all containers or chambers 4a - 4c , which is designed in particular analogously and has a reading unit,
• • a unit for volume measurement and / or weight measurement of the fermenter 1 supplied substrate S and / or the discharged and recycled digestate G,
• A unit for measuring the amount of gas formed,
• A unit for measuring the oxygen content of the biogas,
• • one unit for temperature measurement in the fermenter 1 .
• • a unit for measuring the level in the gas storage tank and
• • One unit for pH measurement in the fermenter 1 ,

• • eine Einheit zur durchflussabhängigen Zudosierung von Mineralstoffen zum zugeführten Substrat S,
• • eine Einheit zum Einblasen von Luft für die Entschwefelung in Abhängigkeit der entstehenden Biogasmenge und des Sauerstoffgehalts,
• • eine Einheit zur Verbrennung des Biogases, wenn sich Füllstand des Gasspeichers dem maximal zulässigen Wert nähert und
• • eine Einheit zum Halten der Fermentertemperatur über ein Thermostat.

In relation to the above-mentioned measuring technology, the biogas plant is controlled 10 , The controller preferably comprises the following units:

• A unit for the flow-dependent addition of minerals to the supplied substrate S,
• A unit for blowing in air for desulphurisation depending on the amount of biogas produced and the oxygen content,
• • a biogas combustion unit when the gas storage tank level approaches the maximum permissible value and
• • a unit for holding the fermenter temperature via a thermostat.

The substrate addition to the fermenter 1 done by an operator. In a "substrate supply" control program, the necessary equipment, units and units start up and the supply can take place. The fill level monitoring can also be done by the operator, for example by means of displays.

The biogas plant 10 to 1 does not necessarily require a substrate or digestate storage, as a storage in the fermenter 1 he follows. A loading and control can be performed by the operator himself the. The added amount of substrate does not have to be constant, but in this case also the resulting amount of gas is not constant. Due to the structure according to the invention, all maintenance work can be carried out from the outside.

Next includes the biogas plant 10 a heat supply device, which both units 2 for a feeder and units for a discharge 3 includes. A heating of the fermenter 1 takes place at the in 1 exemplified system on laid in a fermenter wall heating hoses. The heat required is taken from a hot water tank or a heating return. Alternatively or in combination, the use of a residual heat potential from, for example, domestic waste water from showers, etc. is also possible. The substrate S may additionally during mixing with digestate G in the mixing device 2 B to be preheated. A thermostat is used to set the temperature in the fermenter 1 which should be as stable as possible at 35 ° C.

Because in the biogas plant 10 Gas is transported, a gas-carrying system is required. The gas-carrying system of a small-scale biogas plant, for example 10 must be impermeable to gas. Below are necessary facilities of the biogas plant 10 described.

There are gas pipes from the fermenter 1 and the possibly existing digestate storage to the gas storage 6 and to the spa 7 needed. The gas pipes are equipped with non-return valves. In the gas lines overpressure valves are attached. When the pressure in the fermenter 1 reaches a set value, the valves open and gas flows into the gas storage 6 or is burned directly.

moreover is a gas treatment provided. Before the burning of biogas in conventional burners it has to be processed. The required steps desulfurization and drying are described below.

Desulphurisation takes place via a desulphurisation device 2d , The desulfurization is, for example, via injection of small amounts of air in the gas space of the fermenter 1 or in the digestate storage or carried out via a separate purification step. For the injection of air for biological desulfurization, the oxygen content of the biogas or at least the amount of biogas produced is measured. The required amount of air is dosed via the control. There are areas for the settlement of the sulfur bacteria, such as a wooden scaffolding, provided and optionally a humidifying device is provided.

Further a gas drying unit is provided. The gas drying is necessary and takes place after desulfurization. The gas is passed through a condensation trap passed, in the water fails. The condensate is discharged into the sewage system. It can be easy be sulfuric.

There is also a gas storage 6 provided, which is also designed as a gas storage tank. It is preferably designed so that at least the amount of biogas can be stored one day. The gas storage 6 can be designed as a simple gas storage. The simple gas storage is carried out without pressure, that is, in the gas storage 6 raises the gas pressure of the fermenter 1 one. In order to keep the pressure stable regardless of the level, there is a foil store inside the solid storage tank. Above that, the level in the gas storage can be adjusted 6 determine. To increase safety, the outer shell of the gas storage 6 made of a solid material such as steel. Safety valves are provided to ensure explosion protection.

The gas storage 6 can also be designed as a gas storage with compressor. For example, a pressure accumulator can be used to reduce the required storage volume. For a compressor is needed and the memory must be designed for the higher pressure level consuming. The safety requirements increase with it.

Corresponding Safety devices are provided.

The safety devices can via a combustion of the gas over the thermal bath 7 be realized. It is thus ensured that the resulting gas always over the spa 7 can be burned. Is the gas storage 6 filled to a certain degree, the spa springs 7 and part of the gas is burned to heat a hot water tank. If this is too hot, heat must be discarded by replacing some of the hot water from the store with fresh water.

In addition, gas sensors are provided. Im the biogas plant 10 Surrounding room gas sensors are installed, which can trigger the ventilation of the surrounding space or the extraction of the gas.

The fermenter room 4 , the feeder 2 and / or the discharge device 3 are formed at least in pairs relative to each other movable, with individual units of the feeder 2 or the discharge device 3 can be designed to be relatively movable.

Based on the following 2 to 4 the functional principle of the present invention is described. It shows 2 schematically the process principle of the storage batch process in a fermenter room with three chambers formed as containers in a first phase, 3 schematically the process principle of the storage-batch process in a fermenter room with three chambers formed as a container in a second phase and 4 schematically the process principle of the storage-batch process in a fermenter room with three chambers formed as containers in a third phase.

The biogas plant 10 includes one of at least three chambers 4a to 4c existing fermenter 1 , While one of the chambers 4a is filled over several days, there is the second chamber 4b in the main fermentation phase and from the third chamber 4c the digestate is removed for inoculation of the fresh substrate S. The following table shows exemplary residence times in the various stages or phases. Wechselryhthmus Residence time of the substrate in days per phase total residence Phase 1 Phase 2 Phase 3 average 14 days min 0 days 14 days 14 days 28 days 35 days Max 14 days 14 days 14 days 42 days 20 days min 0 days 20 days 20 days 40 days 50 days Max 20 days 20 days 20 days 60 days

For example, if an alternating rhythm of 14 days is chosen, it starts in each container or chamber 4 after 14 days the next phase. The total residence time with a 14-day cycle is at least 28 days, during which time a sufficient degree of degradation would be achieved. With a residence time of 20 days in each phase, it has already reached at least 40 days to discharge.

Table 2 below shows the sequence of the phases. container Phase 1 Phase 2 Phase 3 4a fill Ferment empty 4b Ferment empty fill 4c empty fill Ferment

First, a chamber 4a or a container filled with substrate S for two weeks, as in 2 shown. The addition of the substrates S takes place with admixture of digestate from the chamber 4c via an airtight conveyor to prevent air from entering the container 4a entered. As soon as the substrate S comes into contact with the bacteria from the fermentation residue, the fermentation begins. During the filling phase, therefore, there is already a methane evolution. The residence time of the substrates S in this phase is between 0 and 14 days, then no further substrates S are added more and the fermenter content continues to ferment as in 3 shown. During that time, container becomes 4c with fresh substrate and digestate from container 4b fed. According to the invention, the chambers 4a - 4c moved relative to the feed and discharge devices. In the last phase, the in 4 is shown becomes container 4a gradually emptied by mixing its contents, mixed with fresh substrate, into containers 4b is introduced. The after 14 days digestate recirculation still in container 4a Remaining digestate G is again taken and recycled. The residence time in the last phase is therefore also 14 days, so that a total residence time of at least 28 days results. The actual amount of fermentation residue discharged after 28 days corresponds to the last amount of substrate introduced into the container, ie only the supply of one day. The remaining digestate G is up to 14 days older. At 25% fermentation residue recycling, the lower 25% of the digestate G would be recycled. The finally discharged fermentation residue G would be at the time of discharge for 28 to 38 days in the fermenter. With the help of the Kom The combination of storage and batch processes makes it possible to reduce the required volume in comparison to the conventional batch process, since no substrate storage is necessary and one can dispense with a digestate storage. The number of required units can be reduced compared to the continuous flow method.

With the method according to the invention, illustrated in the figures, of methods for energy production from biomass, in particular for the production of biogas from biomass, the steps of supplying educts, in particular biomass, converting the starting materials into products and removing the products are duchgeführt. In this case, the method according to the memory batch method is carried out in such a way that the steps of feeding, converting and discharging are carried out at least spatially separated in order to realize a quasi-continuous method. Accordingly, separate chambers are provided for each process step 4a - 4c intended. Thus, each phase - feeding, converting and discharging - in a different chamber, ie spatially separated from each other, are performed.

Claims (13)

Process for the production of energy from biomass, in particular for the production of biogas from biomass, comprising the steps of: supplying educts, in particular biomass, converting the starting materials into products and discharging the products, characterized in that the process is carried out by a storage batch process in which the steps of supplying, converting and discharging the solid and liquid products are carried out at least spatially separated, and in which the gaseous products are removed in the sense of a quasi-continuous process during at least two of the aforementioned steps. Method according to claim 1, characterized in that that feeding temporally parallel to a discharge and / or a conversion is performed. Method according to claim 1 or 2, characterized that feed the step of starting materials feeding of unfermented biomass and feeding a fermented biomass test from a downstream step involves to a fermentation process to start. Contraption ( 1 ) for energy production from biomass, in particular a bioreactor or fermenter for producing biogas from biomass, comprising at least one feed device ( 2 ), at least one discharge device ( 3 ) and one with the feeder ( 2 ) and the discharge device ( 3 ) coupled fermenter room ( 4 ) for receiving and converting biomass, characterized in that the fermenter space ( 4 ), the feeder ( 2 ) and / or the discharge device ( 3 ) are formed at least in pairs relative to each other movable. Contraption ( 1 ) according to claim 3, characterized in that the fermenter room ( 4 ) at least three chambers ( 4a . 4b . 4c ), which in each case optionally by a relative movement of fermenter space ( 4 ), Feeder ( 2 ) and / or discharge device ( 3 ) to each other with the feeder ( 2 ) and / or the discharge device ( 3 ) can be coupled. Contraption ( 1 ) according to claim 3 or 4, characterized in that the fermenter room ( 4 ), the feeder ( 2 ) and / or the discharge device ( 3 ) are formed rotatably and / or translationally movable relative to each other. Contraption ( 1 ) according to one of the preceding claims 3 to 5, characterized in that the chambers ( 4a . 4b . 4c ) are arranged such that when one of the chambers ( 4a . 4b . 4c ) with the feeder ( 2 ), another of the chambers ( 4c . 4a . 4b ) with the discharge device ( 3 ) is coupled. Contraption ( 1 ) according to one of the preceding claims 3 to 6, characterized in that at least two of the chambers ( 4a . 4b . 4c ) of the fermenter room ( 4 ) in their upper regions are gas-conducting with each other. Biogas plant ( 10 ) for energy production and / or energy supply from biomass, characterized in that a device ( 1 ) is provided according to one of claims 3 to 6. Biogas plant ( 10 ) according to claim 7, characterized in that a gas-tight system is provided. Biogas plant ( 10 ) according to claim 7 or 8, characterized in that a monitoring and security system is provided for at least one pressure in the fermenter, in particular in the fermenter room, and / or in a gas storage. Biogas plant ( 10 ) according to claim 7, 8 or 9, characterized in that a heating system for heating the fermenter, in particular the fermenter rooms ( 4 ), is provided. Biogas plant ( 10 ) according to one of the preceding claims 7 to 10, characterized in that at least one interface is provided for connection to a power grid and / or a water network.

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