EP0111505A1 - Process and plant for producing biogas - Google Patents
Process and plant for producing biogasInfo
- Publication number
- EP0111505A1 EP0111505A1 EP83901707A EP83901707A EP0111505A1 EP 0111505 A1 EP0111505 A1 EP 0111505A1 EP 83901707 A EP83901707 A EP 83901707A EP 83901707 A EP83901707 A EP 83901707A EP 0111505 A1 EP0111505 A1 EP 0111505A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- digestion
- tank
- manure
- thermophilic
- mesophilic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
- C12M23/00—Constructional details, e.g. recesses, hinges
- C12M23/58—Reaction vessels connected in series or in parallel
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12M—APPARATUS FOR ENZYMOLOGY OR MICROBIOLOGY; APPARATUS FOR CULTURING MICROORGANISMS FOR PRODUCING BIOMASS, FOR GROWING CELLS OR FOR OBTAINING FERMENTATION OR METABOLIC PRODUCTS, i.e. BIOREACTORS OR FERMENTERS
- C12M21/00—Bioreactors or fermenters specially adapted for specific uses
- C12M21/04—Bioreactors or fermenters specially adapted for specific uses for producing gas, e.g. biogas
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E50/00—Technologies for the production of fuel of non-fossil origin
- Y02E50/30—Fuel from waste, e.g. synthetic alcohol or diesel
Definitions
- This invention relates to a process for producing biogas by digestion of animal manure under production of methane by a continuous process, in which fresh animal manure is supplied to a digestion tank concurrently with the removal of degassed manure from the tank.
- the treatment of the supplied manure takes place in a single digestion tank either by a so-called mesophilic process where the diges- tion and the accompanying production of methane take place at a comparatively low temp-rature of about 35°C, or by a thermophilic process in which the digestion with a more complete degassing of the manure takes place at a temperature of about 55°C.
- the mesophilic process re- quires a comparatively long treatment time if a reason ⁇ able amount of gas is to be evolved, and a complete de- gassing of the manure is difficult to achieve; at the same time, mesophilic process does not make it possible to remove completely pathogenic organisms from the treat- ed manure which after having passed the biogas plant is to be used for fertilizing purposes.
- thermophilic process By the thermophilic process, one achieves a more complete degassing, of the manure, but in order to main ⁇ tain the comparatively high digestion temperature, it is necessary, especially at low outdoor temperatures, to supply a substantial amount of energy to heat the digestor, which reduces the efficiency in respect of energy economy to such an extent that up till now the thermophilic process has not been extensively used, in spite of the fact that it offers substantial environmen ⁇ tal advantages owing to the fact that it results in a degassed manure of a very high fertilizing value, practically odourless and also free of pathogenic orga ⁇ nisms, such as intestinal worms and various pathogenic bacteria, which were contained in the fresh manure.
- OM that the supplied animal manure is, in two separate, successive digestion tanks, subjected first to a meso ⁇ philic digestion at a temperature of about 35°C and afterwards to a thermophilic digestion at a temperature of about 55°C.
- thermophilic process in which starting material plant residue and organic refuse from the vegetable production, such as litter straw, have been decomposed to a substantial ex ⁇ tent as compared to fresh manure. Consequently, the pro ⁇ cessing time for the complete degassing of manure by the thermophilic process is substantially shorter than in the case of a thermophilic process carried out from fresh manure.
- the duration of the thermophilic digestion will typically be of about 6-8 days, while a thermophilic process on basis of fresh manure will typically require a processing time of 3 to 4 weeks.
- a plant according to the invention is characterized in that it con rises an inner digestion tank provided with heating members for the thermophilic digestion of manure at a ten erature of about 55°C, and a surrounding outer digestion tank for the mesophilic digestion of manure at a temperature of about 35°C, which tanks are separated by a common heat- insulating wall and communicate with each other only through a duct provided adjacent to the said wall for transferring mesophilically digested manure from the bottom of the outer tank to the upper part of the inner tank, an inlet duct for fresh manure opening into the upper part of the outer tank and an outlet duct for de ⁇ gassed manure passing from the bottom of the inner tank througt the outer tank, while outlet ducts for the methane gas are respectively connected with each of two separate chambers which are placed above the tanks and are open towards their respective tank.
- thermophilic digestion tank by the mesophilic digestion tank will further reduce the total heat requirement for digestion and degassing of a given amount of manure per time unit.
- the biogas plant com ⁇ prises an inner thermophilic digestion tank 1 surround- ed by an outer mesophilic digestion tank 2, the two tanks being separated by a common heat-insulating wall 3.
- the outer tank 2 has also a heat-insulating outer wall 4.
- An inlet duct 5 for fresh animal manure opens in- to the upper part of the outer tank 2, while in connec ⁇ tion with the common wall 3,, provision is made of a connection duct 6 for transferring the mesophilically digested manure from the bottom of the outer tank 2 to the top of the inner tank 1. From the bottom of the inner tank 1 , an outlet duct 7 for degassed manure passes through the outer tank 2 and the upper part of the outer wall 4.
- each of the tanks 1 and 2 closed by its respective heat-insulating roof, 8 and 9 respectively, so that there is no air connection between the two tanks but only connection through the transfer duct 6.
- Outlet ducts 10 and 11 for methane gas 5 from the inner tank 1 and the outer tank 2, respec ⁇ tively, are passed through the roofs 8 and 9 , re ⁇ spectively.
- the biogas plant according to the invention is of the so-called displacement type where the digestion pro-
- thermophilic digestion process 20 tain the temperature of about 55°C necessary to the thermophilic digestion process, provision is made of a heating coil 12, while a heating pipe 13 is provided for the occasional heating of the outer tank 2 in cold periods, in order to maintain the temperature of about
- the tanks 1 and 2 may, moreover, be provided with devices for instance in the form of circulating pumps for stirring the manure and thus preventing the formation of a so-called floating (supernatant) layer
- Such stirring devices can also in a conventional manner be further designed for comminuting manure, in particular in the outer tank 2.
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Wood Science & Technology (AREA)
- Organic Chemistry (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Zoology (AREA)
- Genetics & Genomics (AREA)
- Sustainable Development (AREA)
- Microbiology (AREA)
- Biotechnology (AREA)
- Biochemistry (AREA)
- General Engineering & Computer Science (AREA)
- General Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Molecular Biology (AREA)
- Clinical Laboratory Science (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Treatment Of Sludge (AREA)
Abstract
Dans la production de biogaz, on obtient une amélioration par rapport aux économies d'énergie avec une baisse de la consommation de chaleur et une réduction du temps de traitement ainsi qu'un engrais animal dégazé inodore de haute valeur fertilisante et exempt d'organismes pathogènes, par digestion de l'engrais dans un procédé continu dans lequel l'engrais passe dans deux réservoirs séparés successifs de digestion, où il est d'abord soumis à une digestion mésophile à une température de 35oC environ et ensuite à une digestion thermophile à une température de 55oC environ. Les réservoirs peuvent être conçus comme réservoirs internes de digestion (1) pour la digestion thermophile et un réservoir extérieur de digestion (2) pour la digestion mésophile, entourant le premier et séparé par une paroi commune thermo-isolante (3) comportant une conduite de transfert (6) pour le transfert de l'engrais digéré de manière mésophile depuis le fond du réservoir extérieur (2) jusqu'au sommet du réservoir intérieur (1), ce qui constitue la seule liaison entre les deux réservoirs.In the production of biogas, an improvement in energy savings is obtained with lower heat consumption and reduced processing time as well as odorless degassed animal fertilizer of high fertilizing value and free from pathogenic organisms , by digestion of the fertilizer in a continuous process in which the fertilizer passes through two successive separate digestion tanks, where it is first subjected to mesophilic digestion at a temperature of about 35oC and then to thermophilic digestion at a temperature around 55oC. The reservoirs can be designed as internal digestion reservoirs (1) for thermophilic digestion and an exterior digestion reservoir (2) for mesophilic digestion, surrounding the first and separated by a common heat-insulating wall (3) comprising a pipe for transfer (6) for the transfer of the mesophilically digested fertilizer from the bottom of the outer tank (2) to the top of the inner tank (1), which constitutes the only connection between the two tanks.
Description
Process and plant for producing biogas.
This invention relates to a process for producing biogas by digestion of animal manure under production of methane by a continuous process, in which fresh animal manure is supplied to a digestion tank concurrently with the removal of degassed manure from the tank.
In known biogas plants, the treatment of the supplied manure takes place in a single digestion tank either by a so-called mesophilic process where the diges- tion and the accompanying production of methane take place at a comparatively low temp-rature of about 35°C, or by a thermophilic process in which the digestion with a more complete degassing of the manure takes place at a temperature of about 55°C. The mesophilic process re- quires a comparatively long treatment time if a reason¬ able amount of gas is to be evolved, and a complete de- gassing of the manure is difficult to achieve; at the same time, mesophilic process does not make it possible to remove completely pathogenic organisms from the treat- ed manure which after having passed the biogas plant is to be used for fertilizing purposes.
By the thermophilic process, one achieves a more complete degassing, of the manure, but in order to main¬ tain the comparatively high digestion temperature, it is necessary, especially at low outdoor temperatures, to supply a substantial amount of energy to heat the digestor, which reduces the efficiency in respect of energy economy to such an extent that up till now the thermophilic process has not been extensively used, in spite of the fact that it offers substantial environmen¬ tal advantages owing to the fact that it results in a degassed manure of a very high fertilizing value, practically odourless and also free of pathogenic orga¬ nisms, such as intestinal worms and various pathogenic bacteria, which were contained in the fresh manure.
With a view to overcoming the energetic and^ en¬ vironmental drawbacks of existing biogas plants, the process according to the invention is characterized in
OM
that the supplied animal manure is, in two separate, successive digestion tanks, subjected first to a meso¬ philic digestion at a temperature of about 35°C and afterwards to a thermophilic digestion at a temperature of about 55°C.
By subjecting successively the animal manure first to a mesophilic digestion and then to a thermo¬ philic digestion, one obtains in the first place an en¬ vironmentally valuable process making the degassed manure intended for fertilizing purposes both odourless and free of pathogenic organisms, so that the process according to the invention is particularly suitable for use in collec¬ tive plants treating manure from a plurality of farms, as it ensure that the degassed manure returned to each farm for fertilizing purposes is not infected with pathogenic organisms of foreign origin.
Moreover, as a result of the first mesophilic digestion process a more homogeneous manure πaterial is supplied as starting material for the subsequent thermo- philic process, in which starting material plant residue and organic refuse from the vegetable production, such as litter straw, have been decomposed to a substantial ex¬ tent as compared to fresh manure. Consequently, the pro¬ cessing time for the complete degassing of manure by the thermophilic process is substantially shorter than in the case of a thermophilic process carried out from fresh manure. In the process according to the invention the duration of the thermophilic digestion will typically be of about 6-8 days, while a thermophilic process on basis of fresh manure will typically require a processing time of 3 to 4 weeks.
For carrying out the process, a plant according to the invention is characterized in that it con rises an inner digestion tank provided with heating members for the thermophilic digestion of manure at a ten erature of about 55°C, and a surrounding outer digestion tank for the mesophilic digestion of manure at a temperature of about 35°C, which tanks are separated by a common heat-
insulating wall and communicate with each other only through a duct provided adjacent to the said wall for transferring mesophilically digested manure from the bottom of the outer tank to the upper part of the inner tank, an inlet duct for fresh manure opening into the upper part of the outer tank and an outlet duct for de¬ gassed manure passing from the bottom of the inner tank througt the outer tank, while outlet ducts for the methane gas are respectively connected with each of two separate chambers which are placed above the tanks and are open towards their respective tank.
This embodiment of the biogas plant with coaxial cylindrical tanks results in a further improvement of the energetic efficiency since the surrounding of the thermophilic digestion tank by the mesophilic digestion tank will further reduce the total heat requirement for digestion and degassing of a given amount of manure per time unit.
The invention will in the following be explained in more detail with reference to the schematic drawing showing a section of an embodiment of a biogas plant according to the invention.
In the embodiment shown, the biogas plant com¬ prises an inner thermophilic digestion tank 1 surround- ed by an outer mesophilic digestion tank 2, the two tanks being separated by a common heat-insulating wall 3. The outer tank 2 has also a heat-insulating outer wall 4.
An inlet duct 5 for fresh animal manure opens in- to the upper part of the outer tank 2, while in connec¬ tion with the common wall 3,, provision is made of a connection duct 6 for transferring the mesophilically digested manure from the bottom of the outer tank 2 to the top of the inner tank 1. From the bottom of the inner tank 1 , an outlet duct 7 for degassed manure passes through the outer tank 2 and the upper part of the outer wall 4.
At the top,' each of the tanks 1 and 2
closed by its respective heat-insulating roof, 8 and 9 respectively, so that there is no air connection between the two tanks but only connection through the transfer duct 6. Outlet ducts 10 and 11 for methane gas 5 from the inner tank 1 and the outer tank 2, respec¬ tively, are passed through the roofs 8 and 9 , re¬ spectively.
The biogas plant according to the invention is of the so-called displacement type where the digestion pro-
10 cess is continuous, since once the process has been started, the supply of fresh manure through the inlet duct 5 takes place concurrently with the removal of degassed manure through the outlet duct 7 and its conveying to a storage vessel (not shown) . The levels
15 of manure in the inner tank 1 and the outer tank 2 will be determined by the position of the lead-in of the outlet duct 7 through the outer wall 4 and of the opening of the transfer duct 6 into the inner tank 1. For heating the inner tank 1 in order to main-
20 tain the temperature of about 55°C necessary to the thermophilic digestion process, provision is made of a heating coil 12, while a heating pipe 13 is provided for the occasional heating of the outer tank 2 in cold periods, in order to maintain the temperature of about
25 35°C for the mesophilic digestion process.
The tanks 1 and 2 may, moreover, be provided with devices for instance in the form of circulating pumps for stirring the manure and thus preventing the formation of a so-called floating (supernatant) layer
30 at the top of the tanks. Such stirring devices can also in a conventional manner be further designed for comminuting manure, in particular in the outer tank 2.
Claims
P A T E N T C L A I M S 1. A process for producing biogas by digestion of animal manure under production of methane by a con¬ tinuous process, in which fresh animal manure is supplied to a digestion tank concurrently with the re- i moval of degassed manure from the tank, characterized in that the supplied animal manure is, in two separate, successive digestion tanks (1, 2), subjected first to a mesophilic digestion at a temperature of about 35°C and afterwards to a thermophilic digestion at a tempe¬ rature of about 55°C.
2. A process as claimed in claim 1, characterized in that the mesophilic digestion is continued until a substantially homogeneous manure material to be supplied to the digestion tank (1] for the thermophilic diges¬ tion is obtained, and that the duration of the thermo¬ philic digestion is substantially shorter than the duration of the mesophilic digestion.
3. A process as claimed in claim 1 or 2, characterized in that the duration of the mesophilic digestion is of about two weeks, while the duration of the thermophilic digestion is of 6 to 8 days.
4. A plant for carrying out the process according to claim 1 or 2, characterized in that it comprises an inner digestion tank (1) provided with heating members (12) for the thermophilic digestion of manure at a tem¬ perature of about 55 C,and a surrounding outer digestion tank (2) for the mesophilic digestion of manure at a ■ temperature of about 35°C, which tanks are separated by a common heat-insulating wall (3) and communicate with each other only through a duct (6) provided adjacent to the said wall for transferring mesophilically digested manure from the bottom of the outer tank (2) to the top of the inner tank (1), an inlet duct (5) for fresh manure opening into the top of the outer tank (2) and an outlet- duct (7) for degassed manure passing from the bottom of the inner tank (1) through the outer tank (2), while common outlet ducts (10, 11) for the methane gas
are respectively connected with each of two separate chambers placed above the tanks (1, 2) and open towards their respective tank.
5. A plant as claimed in claim 4, characterized in that the common wall (3) between the inner and the outer tank (1, 2) and an outer wall (4) for the outer tank (2) are formed of coaxial, substantially cylindrical walls.
-BURE
OKPI
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DK271382A DK271382A (en) | 1982-06-16 | 1982-06-16 | METHOD AND PLANT FOR BIOGAS MANUFACTURING |
| DK2713/82 | 1982-06-16 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP0111505A1 true EP0111505A1 (en) | 1984-06-27 |
Family
ID=8114951
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP83901707A Withdrawn EP0111505A1 (en) | 1982-06-16 | 1983-06-03 | Process and plant for producing biogas |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0111505A1 (en) |
| DK (1) | DK271382A (en) |
| WO (1) | WO1984000038A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013039407A1 (en) | 2011-09-16 | 2013-03-21 | Green Gas As | Modular anaerobic digestion system |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3248703A1 (en) * | 1982-12-30 | 1984-07-05 | Inprohold Establishment, Vaduz | METHOD AND DEVICE FOR CONTINUOUSLY PRODUCING BIOLOGICAL, HUMUS-FORMING DUENGER |
| US5525229A (en) * | 1994-09-14 | 1996-06-11 | North Carolina State University | Process and apparatus for anaerobic digestion |
| FR2744937B1 (en) * | 1996-02-21 | 1998-04-10 | Europ Agence Spatiale | ORGANIC WASTE TREATMENT PROCESS AND PLANT AND APPLICATIONS OF SUCH PROCESS |
| DE19746636A1 (en) * | 1997-10-22 | 1999-04-29 | Nordenskjoeld Reinhart Von | Methane gas generator provided with cavity wall structure |
| EP1280738B1 (en) | 2000-05-12 | 2011-09-14 | United Utilities Plc | Sludge treatment at a mesophilic temperature |
| MY143253A (en) | 2002-08-01 | 2011-04-15 | Gfe Patent As | Method and device for stripping ammonia from liquids |
| DE10345600A1 (en) * | 2003-09-29 | 2005-04-28 | Eisenmann Kg Maschbau | Plant to generate biogas from biomass has fermenting container divided into two zones with heating to give raised temperature in second discharge zone |
| DE102004035997A1 (en) * | 2004-07-16 | 2006-02-02 | Rühl, Bernhard | Biogas plant for the supply of methane-containing gases |
| DE102005054323B4 (en) | 2005-11-11 | 2008-02-21 | Wilhelm Gantefort | Fermenter for the production of biogas from organic material |
| WO2018064993A1 (en) * | 2016-10-09 | 2018-04-12 | Archea New Energy Gmbh | Multi-chamber system for generating biogas |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE630242C (en) * | 1931-06-02 | 1936-05-23 | Franz Fries | Device for utilizing the surplus heat of artificially heated digestion rooms |
| GB462941A (en) * | 1935-06-21 | 1937-03-18 | Dorr Co Inc | Improvements relating to the process of sewage sludge digestion and apparatus therefor |
| AU485782B2 (en) * | 1972-08-24 | 1975-02-27 | Beaumont Stanley | Sewage treatment plant and process |
| DE3042883A1 (en) * | 1980-11-13 | 1982-06-09 | Hans Dipl.-Ing. 6393 Wehrheim Schneider | Biomass conversion to methane and manure - in two reactors in series with specified different temp. levels |
-
1982
- 1982-06-16 DK DK271382A patent/DK271382A/en not_active Application Discontinuation
-
1983
- 1983-06-03 WO PCT/DK1983/000058 patent/WO1984000038A1/en not_active Application Discontinuation
- 1983-06-03 EP EP83901707A patent/EP0111505A1/en not_active Withdrawn
Non-Patent Citations (1)
| Title |
|---|
| See references of WO8400038A1 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013039407A1 (en) | 2011-09-16 | 2013-03-21 | Green Gas As | Modular anaerobic digestion system |
Also Published As
| Publication number | Publication date |
|---|---|
| WO1984000038A1 (en) | 1984-01-05 |
| DK271382A (en) | 1983-12-17 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
| AK | Designated contracting states |
Designated state(s): AT BE CH DE FR GB LI LU NL SE |
|
| 17P | Request for examination filed |
Effective date: 19840629 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
| 18D | Application deemed to be withdrawn |
Effective date: 19850819 |