WO2015063167A1

WO2015063167A1 - Biogas plant with biocarbon-filter arrangement

Info

Publication number: WO2015063167A1
Application number: PCT/EP2014/073243
Authority: WO
Inventors: Mathias Schlegel; Norbert Kanswohl
Original assignee: Universität Rostock
Priority date: 2013-11-01
Filing date: 2014-10-29
Publication date: 2015-05-07
Also published as: DE102013112069A1

Abstract

The invention concerns a biogas plant (10) comprising at least one biogas reactor (11, 12, 13) in which a gaseous product is prepared, and at least one filter arrangement (14, 15) which is able to filter useful material out of the gaseous product from the biogas plant (10) and/or from the at least one biogas reactor (11, 12, 13), the filter arrangement (14, 15) comprising biocarbon which is able to accumulate useful material. The invention also concerns corresponding arrangements and methods.

Description

Biogas plant with biochar filter device

The present invention relates to a biogas plant, a device for collecting valuable material, a device for producing biochar and corresponding methods.

In particular, in biogas production and in biogas, but also in other biological and agricultural processes or materials, often undesirable substances appear that are undesirable or even harmful in the actual product, such as biogas. For example, biogas may contain a component of hydrogen sulphide which would be detrimental to combustion and which therefore has to be filtered out. On the other hand, materials such as sulfur, phosphorus and nitrogen or some of their compounds represent valuable substances that can be used, for example, as fertilizer materials.

It is an object of the present invention to be able to provide such valuable substances as sustainably as possible.

This object is achieved with the devices and methods of the independent claims.

Advantageous embodiments and development will become apparent from the dependent claims.

In the context of this description, a biogas plant can generally be a device which is designed to produce biogas from a substrate by fermentation, in particular by anaerobic digestion. Biogas can contain methane as an essential energy source. During fermentation As a rule, there are four different degradation phases, namely a hydrolysis phase, an acidogenesis phase, an acetogenesis phase and a methanogenesis phase. These phases can be run together in a reactor. Alternatively, a biogas plant may have separate reactors for different phases, so that substrate is pumped from one reactor to another for passing through all phases. Thus, for example, a biogas plant may have a hydrolysis reactor in which the hydrolysis and optionally the acidogenesis phase are passed through, and a downstream fermentation reactor may be provided in which the methanogenesis and optionally the acetogenesis are passed through. After passing through the methanogenesis remains a digestate of substantially organic material in which, inter alia, lignocellulose is included, which is not or not completely degraded during biogas production. A gas or gas mixture that is produced in a reactor of the biogas plant can be referred to as gaseous product or product gas. As a valuable material can be considered in particular a substance that is used for fertilization, such as sulfur and / or sulfur compounds such as hydrogen sulfide and / or methyl mercaptan and / or ethyl mercaptan and / or dimethyl sulfide and / or carbonyl sulfide, and / or phosphorus and phosphorus compounds such as phosphate and / or nitrogen and / or nitrogen compounds such as ammonia. Biochar may generally refer to a char produced by charring from a biological material, especially coal derived from the charring of lignocellulose. The charring can take place in a charring device. A charring device may generally be configured to treat charred material at a suitable temperature and pressure to produce coal. Pressure and temperature may be adjusted or adjustable to adjust desired properties of the biochar produced, in particular Surface properties such as porosity and / or grain size and / or structure size and the ability to accumulate certain recyclable material and / or filters. The temperature for charring may be, for example, between about 180 ° C and 230 ° C. It is conceivable that water is added to the material to be carbonized during and / or for charring. The properties of biochar may depend on the material from which the recyclables are to be derived. Thus, for example, biochar which is intended to filter and / or collect a valuable substance, such as sulfur or a sulfur compound, from a gaseous material may have a different surface structure and / or structure size than biochar, for example for filtering and / or accumulating phosphorus or phosphorus compounds from manure is provided. Biochar, in particular biochar of a filter device, can generally have a surface coating and / or a material for influencing pores and / or surfaces, in particular for pore surface control, for example for pore activation and / or doping and / or impregnation, which accumulation and / or filtration one or more of certain valuable substances. For example, biochar may be treated with a material catalytically active for a particular desired pool of valuable material. It is conceivable that biochar is treated with citric acid and / or nitric acid to favor nitrogen deposition. It is also conceivable that during and / or prior to charring a starting material of the charring, such as fermentation residues, a material influencing the properties of the biochar to be produced, for example the pore size, is added, for example a catalytically active material. A corresponding material may include, for example, citric acid and / or phosphoric acid. The use of appropriate biochar allows the enrichment and compaction of valuable materials and optimal use existing resources, especially in biogas production.

According to the invention, a biogas plant with at least one biogas reactor is provided, in which a gaseous product is provided. The biogas plant has at least one filter device which is capable of filtering valuable material from the gaseous product of the biogas plant and / or the at least one biogas reactor, wherein the filter device comprises biochar, which is able to accumulate valuable material. Thus, the valuable material can be accumulated on the biochar, with which it can be used as fertilizer or as a fertilizer component. At the same time the recyclable material is removed from the gaseous product, where it is usually undesirable. The biogas plant may in particular comprise a hydrolysis reactor whose product gas may contain sulfur and / or a sulfur compound such as hydrogen sulphide and / or one of the abovementioned compounds, which may be regarded as a valuable substance. The biochar of the filter device can be designed to adsorb sulfur and / or hydrogen sulfide and / or a sulfur compound and / or sulfur from such a compound, in particular from hydrogen sulfide. Alternatively or additionally, a filter device for collecting valuable material from a gaseous product of a methane-producing reactor may be provided, for example a fermentation reactor and / or a biogas reactor in which all four phases are carried out. A biogas plant can generally have an electronic control device, which can be connected or connectable to control and monitor the biogas plant with sensors and / or switches and / or valves and / or pumps. In general, a plurality of filter devices may be provided, which may have different types of biochar to enrich different recyclables. The biogas plant may be connected to a charring device or connectable. Fermentation residues from the biogas plant can be provided to the carbonization device for charring. The charring device may be designed to carbonize fermentation residues from the biogas plant of the charring facility. The biogas plant may be designed such that waste heat from the biogas plant of the charring device is provided. The waste heat can originate, for example, from a bioreactor of the biogas plant, for example from a hydrolysis reactor and / or fermentation reactor and / or biogas reactor, in which all four phases are passed. In a variant it can be provided that the biogas plant has a device for converting biogas into energy such as electric current and / or heat, such as a burner and / or a generator and / or a fuel cell arrangement. It is conceivable that the biogas plant is designed to provide waste heat from such a device and / or several such devices, the charring device. For this purpose, the charring device may be in heat-transmitting contact with one or more waste heat producing devices. Alternatively or additionally, the biogas plant may be designed to supply waste heat via a heat carrier medium heated by one or more waste heat-producing devices, for example a fluid such as water and / or steam, to the charring device. Thus, the efficiency of the biogas plant can be increased and at the same time the digestate can be reused. It may alternatively or additionally be provided that biogas produced in the biogas plant is provided and / or used for operating the charring device, for example by being fed to a burner of the charring device, for example in accordance with a biogas plant and / or the charring plant. device monitoring and / or controlling control device.

In a further development, the biogas plant can have a hydrolysis reactor for carrying out a hydrolysis reaction and a downstream fermentation reactor. The filter means may be arranged to filter gas generated in the hydrolysis reactor, such as to enrich the biochar with hydrogen sulphide and / or sulfur. Alternatively or additionally, a filter device for filtering gas from the fermentor can be provided.

The invention also relates to a device for collecting valuable material with a filter device. The filter device has biochar, which is designed to accumulate valuable material. The biochar can be designed to accumulate a particular valuable material and / or certain valuable substances. The biochar may be biochar as described herein. The filter device may be a filter device described herein. For example, the filter device can be provided to filter valuable material from a gas or a liquid. It is conceivable that the filter device is intended to filter phosphorus and / or phosphorus compounds such as phosphate from agricultural waste such as manure and / or digestate and accumulate on the biochar.

It is conceivable that the device is designed to accumulate valuable material from a product gas of a biogas plant on the biochar. The biogas plant may be a biogas plant as described herein. Alternatively or additionally, a filter device for filtering recyclable material from fermentation residues of the biogas plant may be provided, for example for filtering phosphorus and / or phosphorus compounds such as phosphate. Furthermore, a device for producing biochar is provided, which has a charring device, which is designed to carbonize fermentation residues from a biogas plant. The charring means may be a charring means described herein. It is intended to use a charring device described herein for converting digestate of a biogas plant into biochar. This can be produced for different types of biochar, such as by adjusting the water content and / or pressure and / or temperature and / or time course and / or drug delivery.

In general, the charring device can be designed as part of a biogas plant, in particular as part of a biogas plant described herein.

The charring means may be adapted to treat the biochar with at least one active agent after and / or during charring. Such an agent may be designed to produce certain properties of the biochar produced during charring. Alternatively or additionally, an active ingredient can be provided to adapt the surface properties of the biochar and / or to influence the pores of the biochar, in particular to dope and / or impregnate and / or activate it in order to promote the accumulation of certain valuable material.

In addition, a process for the production of biochar is provided in which fermentation residues are converted from a biogas plant to biochar. The method may in particular be operated or operable with a charring device described herein. A method is also provided for operating a biogas plant, in particular one described herein

Biogas plant. The method comprises the steps of providing a gaseous product in at least one biogas reactor of the biogas plant and filtering out and collecting recyclable material from the gaseous product using a biochar filter means, wherein valuable material is accumulated on the biochar. Further, the step of charring, by a charring means, fermentation residues of a biogas plant to produce biochar is provided. In particular, biochar can be made for use in the filter device. The biogas plant may be a biogas plant as described herein. Waste heat of the biogas plant, in particular waste heat of one or more biogas reactors and / or at least one burner and / or at least one generator and / or at least one fuel cell arrangement can be supplied to the charring means to operate and / or to heat them. It is conceivable that the charring device biogas is supplied from the biogas plant, in particular in order to be implemented by the charring device as by combustion in Betriebswäre.

Hereinafter, a variant of a biogas plant will be described with reference to the accompanying figure.

It shows:

Fig. 1 shows schematically an example of a biogas plant.

Fig. 1 shows schematically an example of a biogas plant 10. The biogas plant 10 has a biogas reactor device 11 which comprises a reactor for carrying out all phases of Fermentation or alternatively a first hydrolysis reactor 12 and a fermentation reactor 13 may have. In the reactor device 11 generated gas, such as gas generated in the hydrolysis reactor 12 is passed through a filter device 14 which has as an active filter element biochar, which is adapted to sulfur and / or sulfur compounds, in particular sulfur ^¬ hydrogen to filter out of the product gas and to accumulate. If only one reactor is present, the biogas produced is passed through the filter device 14. It is conceivable that at least one further filter device 15 is present, for example to collect nitrogen and / or nitrogen compounds from the product gas in biochar. Such a filter device may be connected upstream or downstream of the filter device 14. Alternatively, the filter means may be provided from a hydrolysis reactor 14 for filtering of the product gas, while as shown a further filter device 15 may be provided for filtering of valuable material, in particular nitrogen and / or StickstoffVerbind ^¬ Ungen from a product gas of a fermenting reactor. 13 Product gas from the hydrolysis reactor 12 can be fed to a fermentation reactor 13 and / or be provided for another use. After going through the

Hydrolysis reactor 12, the substrate to be fermented is transported into the fermentation reactor 13: If only one biogas reactor for all stages of fermentation is present, corresponding arrangements are eliminated. Furthermore, a filter device 16 may be provided, which is able to filter recyclable material such as phosphorus and / or phosphorus compounds such as phosphate from digestate, which arise in the reactor device 11, in particular in the fermentation reactor 13. Such a filter device 16 may in the range of an outlet for fermentation residues be provided downstream of the reactor device 11 or such. It can be provided on a sweeping device, which is able to swell fermentation residues with water in order to transport them more easily through the filter device 16 can. The biogas plant 10 in this example also has a charring device 18, to which fermentation residues can be fed. The charring device 18 may be disposed downstream of the filter device 16. The charring device 18 is intended to carbonize fermentation residues, in particular to char and optionally treat them with active ingredient, that the biochar can be used for the filter device 14 and / or the filter device 15 and / or the filter device 16. In this case, different types of biochar can be produced for the various filter devices, for example by adjusting the water content and / or pressure and / or temperature and / or time course and / or drug delivery. The biogas plant also has a waste heat generating device for generating energy from biogas 20, which may include, for example, a burner and / or a fuel cell and / or a generator. Waste heat from the device 20 is supplied to the charring device 18. Optionally, a supply of waste heat from the reactor device 11 take place. Alternatively or additionally, it may be provided that the charring device 18 is supplied with biogas from the biogas plant 10. For example, a burner of the charring device 18 can be operated with biogas. It will be understood that the biogas plant has suitable valves, conduits, pumps and similar transport means to properly transport gas and / or digestate and / or solids such as biochar. Depending on requirements, it may be advantageous not to use all filter devices 14, 15, 16. In particular, the filter device 15 and the filter device 16 are each to be regarded as optional. The charring device 18 may also be optional.

In operation, the biogas plant 10 is characterized by a comprehensive use of resources. Fermentation residues are only from Recycled material and then converted into biochar, which in turn is used as a filter. If sufficient resources have accumulated in the biochar, this can be used for fertilization. Waste heat of the plant can be exploited to operate the charring of digestate.

Features described herein may be individually or in any combination relevant to the practice of the invention.

LIST OF REFERENCE NUMBERS

biogas plant

bioreactor facility

hydrolysis reactor

fermentation reactor

filter device

Charring device

Energy generator

Claims

Protection claims 1. Biogas plant (10) with at least one biogas reactor

(11, 12, 13), in which a gaseous product

and at least one filter device (14, 15) which is capable of filtering valuable material from the gaseous product of the biogas plant (10) and / or the at least one biogas reactor (11, 12, 13), the filter device (14, 15) being biochar includes which recyclable material can accumulate.

2. biogas plant according to claim 1, wherein the biogas plant (10) connected to a charring device (18) or

is connectable to fermentation residues from the biogas plant (10) of

To provide charring device (18) for charring.

3. biogas plant according to one of the preceding claims, wherein the biogas plant (10) a hydrolysis reactor (12) for

Performing a hydrolysis reaction and a downstream fermentation reactor (13), wherein the filter means (14) for filtering in the hydrolysis reactor (11) generated gas is arranged.

4. means (14, 15) for collecting recyclable material with a filter device;

wherein the filter device comprises biochar, which is designed to accumulate valuable material.

5. Device according to claim 4, wherein the device (14,

15) is adapted to accumulate valuable material from a product gas of a biogas plant (10) to the biochar.

6. A device for producing biochar, which has a charring device (18) which is designed to carbonize fermentation residues from a biogas plant (10).

7. Device according to claim 6, wherein the

Charring device (18) is formed as part of a biogas plant (10), in particular as part of a biogas plant (10) according to one of claims 1 to 3.

8. Device according to one of claims 6 or 7, wherein the charring means (18) is adapted to the

Biochar after and / or during charring with a

To treat active ingredient.

9. A process for the production of biochar, wherein fermentation residues from a biogas plant (10) are converted to biochar.

10. A method for operating a biogas plant (10), in particular a biogas plant (10) according to one of claims 1 to 3 or 7, with the steps:

Providing a gaseous product in at least one biogas reactor (11, 12, 13) of the biogas plant (10);

Filtering out and collecting recyclable material from the gaseous product using a biochar filter means (14, 15), wherein biocarbon is valuable

is accumulated; and

Charring, by a charring means (18), of digestate of a biogas plant (10) to produce biochar, in particular biochar for use in the biochar

Filter device (14, 15).