DE102008030653A1 - Method for increasing biogas yield of a biodegradable substrate with a hydrolysis stage and a thermal disintegration stage, comprises preventing the formation of the methane gas in the hydrolysis stage by adjusting the individual parameter - Google Patents

Abstract

The method for increasing biogas yield of a biodegradable substrate with a hydrolysis stage (2) and a thermal disintegration stage (4), which is carried out between the hydrolysis stage and a methane stage (5), comprises preventing the formation of the methane gas in the hydrolysis stage by adjusting the individual parameter. The hydrolysis stage is carried out at 38[deg] C with a pH-value of 5.5-6.5. Fructooligosaccharides (FOS)/toxic air contaminant (TAC) factor in the hydrolysis stage is 2-3. The retention time of the substrate in the hydrolysis stage is 5 hours to ten days. The method for increasing biogas yield of a biodegradable substrate with a hydrolysis stage (2) and a thermal disintegration stage (4), which is performed between the hydrolysis stage and a methane stage (5), comprises preventing the formation of the methane gas in the hydrolysis stage by adjusting the individual parameter. The hydrolysis stage is carried out at 38[deg] C with a pH-value of 5.5-6.5. Fructooligosaccharides (FOS)/toxic air contaminant (TAC) factor in the hydrolysis stage is 2-3. The retention time of the substrate in the hydrolysis stage is 5 hours to ten days. The initial substrate in the hydrolysis stage has a trypsin-sensitive (TS) portion of greater than 30%. The thermal disintegration stage is operated at 70[deg] C with a pH value of 5.5-7. The retention time of the substrate in the thermal disintegration stage is 1-2 hours. The FOS/TAC factor in the thermal disintegration stage is 1.5-2.5. The methane stage is carried out at 50-55[deg] C with a pH-value of 7.5-8.0. The FOS/TAC factor in the methane stage is 0.3. The retention time of the substrate in the methane stage is 20-35 days. The concentration of the FOS factor is initially 15000 mg/l to finally 5000 mg/l, and the concentration of the TAC factor is initially 5000 to finally 15000 mg/l. An INDEPENDENT CLAIM is included for a plant for increasing biogas yield of a biodegradable substrate with a hydrolysis stage, a thermal disintegration stage and an anaerobic methane stage.

Description

The The present invention relates to a method and a Plant for increasing the biogas yield of a degradable substrate, in particular with a method and an installation in which the respective stages are operated under optimal conditions.

Such biogas plants and processes are from the EP 99968313.9 known. A similar process is still from the FR 2 711 980 known. Although these known processes also have two anaerobic digestion stages, between which a so-called thermal disintegration stage is connected, they have the disadvantage that the initial ratio of FOS (volatile organic acids) / TAC (total inorganic carbon) in the first digestion stage is as good as is unknown and one can assume an approximately equal concentration of the FOS value and the TAC value of about 10,000 mg / l, wherein the FOS concentration decreases in the course of the Ausfaulprozesse due to the acid consumption for methane gas production and the TAC concentration increases ,

When It is disadvantageous that already in the first stage Methane gas is formed to a not inconsiderable extent, resulting in adversely affects the mechanical design of the plant. Furthermore, in the known from the prior art systems of pH in the first Ausfaulstufe relatively high, which limits methane gas formation in subsequent stages becomes.

The from the EP 99968313.9 In the prior art known plant for biogas production has a horizontally lying cylindrical Berverhältnis, the diameter of about 3.80 m and a length of about 24 m, whereby manufacturing difficulties may occur. On the outside of the container, both an insulation of 60 mm thickness and a heating system is arranged. The heating system consists of welded U-steels, which run alongside on the outside of the cylinder, which provides a relatively low heat transfer to the substrate to be heated. Another disadvantageous feature of the container is the stirrer shaft, which is divided into two parts and each part is about 12 m long. The agitator shaft is equipped with so-called paddles, which rotate within a diameter of 3.60 m inside the container. The drive of the stirrer shaft is operated by a geared motor with a power of 3 KW. The speed of the stirrer shaft is limited to three to five revolutions per minute. The sealing of the stirrer shafts with respect to the ausfaulbaren substrate is carried out with a so-called mechanical seal, which is pressed together with a spring force. The ceramic plane surfaces form a dynamic seal. Within the container further bearings of the shaft are included. The bearings are provided with plain bearings made of plastic.

When disadvantageous in this system, it is considered that the main fermenter must be delivered in two parts of approx. 12 m in length, to be put together on site. The separation point, the in this case represents a flange, is when setting up adjusted and welded from the inside liquid-tight. The work on the construction site to make this connection are relatively expensive and time-consuming.

Further it is not without problems, the welds and manufacture tests to meet the requirements correspond to a biogas plant.

Farther is the thermal disintegration stage by means of a water jacket, the one around the container in which the one to be heated Biomass is located, lying around. This water jacket consists of a pressure-resistant outer shell and a pressure-resistant Inner sheath. Due to the resulting annulus is the Water of the heating system pumped.

Thereby results in a heat transfer from the outside thermal heated annulus volume to the internal volume of use.

Of the Disadvantage of such a constructed annular space heater for the thermal disintegration stage is that due the relatively high pressures within the annulus the walls relative must be designed strongly, which is costly and technical is expensive.

Further it is disadvantageous that the heat conduction of the heating medium within the shell is not sufficient because of the arrangement the flow plates within the shell the heat distribution is uneven.

From the FR 2 711 980 A1 a method is known in which in a one-stage digestion process after the first phase in which takes place the hydrolysis and acidification, even before the second phase in which the methane gas is formed and a thermal treatment is inserted, which is disadvantageous in terms of Overall yield of biogas.

In view of the ever-increasing requirements for the prevention and reduction of waste and pollutants, it is essential to think about the further degradation of energy-containing substances. From world political and economic Reasons, new plant concepts and technologies should be created to improve the overall balance. With increasing substrate costs for biomass plants, it is important that the substrates used in optimal. adapted to the individual process stages conditions are reduced with a significantly higher degree of degradation. This aspect of better overall utilization of the substrates used is of great importance for the environment and the economy.

It is therefore an object of the present invention to simplify the design of the biogas plant due to adjustable parameters of the initially introduced substrate and to reduce the overall CO ₂ balance, so that the plant is more cost-effective to manufacture and works more effectively in the individual degradation processes.

These The object is achieved by the characterizing features of the main claims solved.

According to the invention the method of increasing the biogas yield of a biological degradable substrate having at least one hydrolysis step and at least a thermal disintegration stage, which between the at least a hydrolysis step and at least one methane stage is arranged characterized in that by setting the individual parameters at least in the at least one hydrolysis step the formation of Methane gas is prevented.

Advantageous it is there that the at least one hydrolysis step between 35 ° C and 45 ° C, but preferably at about 38 ° C.

Farther it is advantageous that at least one hydrolysis step with a pH between 5 and 7.5, preferably between 5.5 to 6.5.

Further it is beneficial to change the FOS to TAC factor in the hydrolysis step between 1 to 4, preferably between 2 to 3.

Further it is advantageous, the residence time (VWZ) of the substrate in the at least a hydrolysis step depending on the substrate between 5 hours to select up to ten days, preferably between 2 to 10 Days.

Further it is advantageous that the initial substrate has a dry matter content of> 30%.

Farther It is also advantageous that the thermal disintegration stage operated with a pH between pH = 5.0 and pH = 7.5, preferably between 5.5 to 7.

Further it is advantageous to use the FOS / TAC factor of the thermal disintegration stage between 1 and 3, preferably between 1.5 and 2.5.

One Another advantage is seen in that the residence time of the substrate in the thermal disintegration stage between 0.5 and 1.5 hours is, but preferably at one hour.

Further it is advantageous that the thermal disintegration stage at Temperatures between 65 ° C and 80 ° C, preferably but operated at about 70 ° C.

One Another advantage is seen in that the at least one methane level is operated at a pH between pH 7 and pH 8.5, preferably between 7.5 to 8.0.

Advantageous it is further that the FOS / TAC factor of the methane level between 0.2 and 0.4, preferably at a FOS / TAC factor of ca. 0.3.

Advantageous it is further that the methane level between 45 ° C to 60 ° C. is operated, preferably between 50 ° C to 55 ° C.

Farther it is also advantageous that the methane stage with a residence time of the substrate is operated between 15 to 35 days, preferably between 20 to 35 days, with the actual residence time of respective substrate is dependent.

One An essential advantage is seen in the fact that the initial Concentration of the FOS factor at around 15,000 mg / l and at the end at about 5,000 mg / L and the concentration of TAC factor at baseline about 5,000 mg / l and at the end of the residence time at about 15,000 mg / l lies.

The adapted to the inventive method plant to increase the biogas yield of a substrate used with at least one hydrolysis step and at least one thermal disintegration step and at least one methane level, which after the o. g. Procedure created are distinguished by the fact that between the at least one essentially horizontal hydrolysis step and the at least a methane level at least with its longitudinal axis perpendicular standing thermal disintegration stage is arranged, wherein the Hydrolysis stage and the thermal Desinintergationsstufe so constructed is that they can be prepared ready for production and set up in the shortest possible time already tested on site and can be operated.

there it is advantageous that the longitudinal axis of the at least a hydrolysis step is arranged substantially horizontally.

Advantageous it is also that the stirrer shaft is hollow inside and the Cavity is filled with a gas.

One Another advantage is seen in the fact that the diameter of the stirring shaft between 25 cm and 50 cm, which is essentially of the size the hydrolysis or the system depends.

Advantageous it is also that the entire at least one agitator shaft disposed within the container of the hydrolysis step is.

All It is particularly advantageous that the hydrolysis step is an elongated Containment in which at least one stirring shaft and at least one heating pipe parallel to the longitudinal axis is arranged, wherein at the stirring shaft at least one stirring element is arranged and the individual stirring elements helical are arranged on the shaft.

Advantageous it is also that at the stirrer shaft at least one dry storage is arranged.

Advantageous It is also that the stirrer shaft at one end with a Floating bearing and the other end with a fixed bearing with axial seal is stored.

Farther It is advantageous that the bottom of the container a has weak inclination and in an end region of the container at least one sand discharge element is arranged.

One Another advantage is seen in that the longitudinal axis the thermal disintegration stage vertically and the second agitator shaft is arranged on a bearing block.

Advantageous it is also that within the thermal disintegration stage at least two fluid passage devices are arranged, wherein at least one of them formed like a pipe coil is.

Farther it is advantageous that the tube-shaped liquid flow device of surrounded by a water jacket.

in the The following is the method according to the invention and the associated system based on drawings in detail explained in more detail. It shows

1 : a schematic block diagram of a system according to the invention ( 1 );

2 : a diagram showing the qualitative functional relationship between the concentration (ml / l) of the FOS and the TAC as a function of time (t) / space (r);

3 : the basic technical structure of the plant ( 1 ) with a hydrolysis step ( 2 ), a thermal disintegration stage ( 4 ) and a methane level ( 5 );

4 : the basic technical structure of a hydrolysis stage ( 2 );

5 : a detailed representation from the inside of the hydrolysis stage ( 2 );

6 : the basic technical structure of a thermal disintegration stage ( 4 );

In 1 is a schematic block diagram of a system according to the invention 1 shown. The substrate used is via a supply line 3 a first hydrolysis step 2 in which the introduced substrate is digested under optimum hydrolysis conditions and prepared for further processing in the following stages. The special features of this hydrolysis step 2 On the one hand, it makes sense to set the FOS / TAC value to about a factor of 3 compared to a typical biogas plant in which the FOS / TAC Value is about 0.3 to 1. By this optimal condition, the substrate can be very well digested. The substrate-dependent residence time of 5 hours to 10 days significantly enhances the effect of the hydrolysis. In this hydrolysis step 2 Almost exclusively, the substrate used is digested, with virtually no methane formation takes place. Following the hydrolysis step 2 the degradable substrate enters a disintegration stage 4 in which the degradable introduced substrate is subjected to a further digestion treatment, which is already heated in the hydrolysis step before digested substrate to a preferred temperature of about 70 ° C and held at this temperature for about one hour. In general, the digestion treatment is carried out at an elevated temperature between about 60 ° C and about 95 ° C in a time interval of about 30 minutes to 120 minutes, so that the digestion of the substrate occurs only when the substrate has undergone the usual degradation processes , In the thermal disintegration, not only pathogens and parasites are largely killed, but also the aerobic biocenosis from the hydrolysis step 2 largely killed and thus made available for faster anaerobic degradation in the following stage. Following thermal disintegration, the substrate enters at least a first stage of the methane 5 in the wake of the previous complete up conclusion of the substrate by the thermophilic methane bacteria biogas is generated. The methane level 5 is operated in optimal conditions between 45 ° C and 60 ° C, with the most favorable range between 50 ° C and 55 ° C. In these temperature ranges, the conversion rate and the bacterial doubling time are significantly higher than for mesophilic bacteria. In a period of 20 to 35 days, the substrate is now almost completely degraded. Following the methane level 5 The almost completely degraded substrate is placed in a collecting container 7 in which the substrate is provided for further technical use. In this way described here can be achieved with the inventive arrangement or investment of the individual facilities a much better overall balance of the entire system.

2 shows a diagram representing the qualitative functional relationship between the concentration (mg / l) of the FOS value and the TAC value as a function of time (t) and space (r). On the vertical axis, the concentration in mg / l and on the horizontal axis, the time (t) or the spatial arrangement of the individual stages is qualitatively represented. The special feature of the system according to the invention is, on the one hand, that the FOS value in the hydrolysis step 2 initially begins at a concentration of about 15,000 mg / l and continuously decreases over time and space up to a concentration of about 5,000 mg / l. In contrast, the TAC value starts at a concentration of 5,000 mg / L and increases continuously over time and space until the end of the residence time of the substrate in the methane stage 5 in the plant up to a value of about 15,000 mg / l too. This shows that the newly designed biogas plant in the hydrolysis stage opens up the substrates used much better, which is characterized by the relatively high acid content of 15,000 mg / l. For the better the substrate is split by the hydrolysis bacteria, the more acids are formed, which are responsible for the methane gas production significantly. In order to use the higher acidity also with a high efficiency. the system was optimally adapted to this mode of operation.

In the methane level 5 in which the residence time is preferably 20-35 days, the acids formed are now utilized very quickly by the methane bacteria and the desired biogas is produced.

As a result of this procedure, the almost complete pre-digestion of the substrate in the hydrolysis step occurs 2 and the thermal disintegration stage 4 a significantly more effective gas yield than in conventional biogas plants.

A special feature of the method according to the invention is that due to a greater density of the degradable substrate in the hydrolysis step 2 a relatively strong acidification occurs in a relatively short residence time, whereby the time of degradation of the acids almost exclusively in the temporally at the end of the entire process lying Methanstufe 5 is laid, in which then a more efficient and complete degradation of the introduced substrate is ensured. In particular, this also improves the overall balance of CO ₂ production by biogas plants, because the discharged from the biogas plant residual substrate contains less degradable substance, which are then degraded in the fields for uncontrolled methane gas formation. The new process and the associated improved plant represent a new step towards a more positive overall balance of biomass plants.

3 shows the basic technical structure of the system 1 with a hydrolysis step 2 , a thermal disintegration stage 4 and a methane level 5 , The hydrolysis step 2 consists of an approximately 18 m long, almost horizontally lying container with an inner diameter of about 3.80 m, with a stirrer shaft 2 ' , the helical of stirring paddles 4 ' is occupied, is penetrated. Parallel to the stirrer shaft 2 ' run inside the container 6 in the edge region of the walls, the heating pipes 12 with which the filled substrate is brought to a certain uniform temperature between 25 ° C and 45 ° C. As a result of the direct contact of the heating pipes 12 With the substrate, a much more efficient heat transfer is introduced into the substrate. The FOS / TAC value is about 2 to 3 while the pH is between 5.6 and 6.5. The residence time of the substrate is preferably substrate-dependent between two to ten days. The initial supplied substrate contains about 30% dry matter. By adding pH-adjusting or similar substances, the pH is optimally adjusted to an ideal value for the given degradable substrate. After a typical residence time of between two and ten days, the substrate is passed through a conduit 30 in the thermal disintegration stage 4 pumped. The thermal disintegration stage 4 consists of a vertical cylindrical container, that of a second stirring shaft 29 is permeated. The substrate lingers for about one hour with a FOS / TAC of 1.5 to 2.5 at 70 ° C and a pH of between 5.5 and 7 in the thermal disintegration step 4 , Following this, the substrate is passed over the line 29 ' into the methane stage 5 transported. The methane level 5 consists of a relatively large cylindrical base container 31 over which a gas-tight hood 25 , usually made of plastic, is stretched. In the methane level 5 becomes the completely digested substrate by means of the thermophilic Methanbakterien to biogas at an ideal temperature between 50 ° C to 55 ° C, a FOS / TAC value of about 0.3 and a pH between 7.5 and 8.0 degraded. The residence time in the methane stage is about 20 to 35 days.

The 4 shows the basic technical structure of a hydrolysis step according to the invention 2 , The hydrolysis step 2 consists of a container 6 which is about 18 m to 20 m long and has a diameter of about 3.5 m to 4 m. The stirring shaft 2 ' is with a variety of stirring paddles 4 ' helically occupied on the circumference. The stirring shaft 2 ' itself is hollow inside and filled with a suitable gas. As a rule, the suitable gas is normal air. The ends of the stirrer shaft 2 ' are each provided by two special bearings 1' and 5 ' stored. The outer jacket of the container 6 is provided with a highly effective insulation of about 80 mm. Inside the jacket is the heating or the heating pipes 12 consisting of three longitudinal tubes with rectangular profile. The heating pipes are on the inner cylinder along the container 6 created and connected by welded joints. The air volume of the stirrer shaft 2 ' is designed so that the buoyancy force is approximately equal to the shaft weight of the stirrer shaft 2 equivalent. As a result of this technical measure, there are no further supports during the operation of the hydrolysis step 2 inside the container 6 required. Only for the commissioning of the hydrolysis stage 2 , in which at this time no substrate is filled, two Abstützgleitlager are arranged at a distance of about 6 m. The support bearings 3 ' Only a small amount of friction is applied as long as the weight of the stirrer shaft is so great that it bends and makes contact with the plain bearings 3 ' he follows. The shaft seal against the medium on the drive side is equipped with multiple radial shaft sealing rings arranged one behind the other 5 ' realized. There is a chamber between the third and fourth radial shaft seal. The chamber is pressurized with a barrier liquid. The opposite side of the stirrer shaft 3 ' is stored with a so-called floating bearing, which is located within the substrate, so that the substrate itself lubricates the bearing. Due to the relatively low mechanical load, this floating bearing 1' a relatively long life, the wear is extremely low. The maintenance of the camp is with little technical effort at half drained level of the container 6 possible. The support bearings 3 ' inside the container 6 , which are required for commissioning and in the event that the shaft is not yet in the floating state, consist of two V-shaped plates made of PTFE. This material is relatively low friction. The V-bearing is below the flange connection of the stirrer shaft 2 ' arranged. The bottom of the container 6 is aligned almost horizontally with a slight slope, with the ends of the container on foundation blocks 11 be stored. At one end of the container are Sandaustragungseinrichtungen 7 provided by the possible sand and rock fragments, which are deposited at the end of the container, sucked and executed. At one end of the container 6 is the filler neck 9 arranged for the solids of the substrate. At the other end of the container 6 is the so-called gas dome 8th arranged, which represents a collecting volume for the gas formation and a discharge valve for forming gases. The advantage of such an overall construction of the hydrolysis step 2 Among other things is that the entire container can be made in one piece and complete with the stirrer shaft 2 ' is delivered. It is also advantageous in this construction that the entire hydrolysis 2 already tried and tested at the production site. This results in a relatively rapid construction of the entire system at the final location.

The 5 shows a fragmentary perspective view of the basic technical structure of a sliding bearing 3 ' that the stirrer shaft 2 ' at start-up of the hydrolysis stage 2 supported. The plain bearing 3 ' is meaningful way below a flange 21 arranged, which is the two shaft parts of the stirrer shaft 2 ' connects with each other. The storage consists essentially of two V-shaped interconnected carriers 22 , which in a suitable place a lubricious material, for example PTFE plastic 23 take up. These support bearings 3 ' are loaded only as long as no substrate in the hydrolysis step 2 is introduced.

The 6 shows the basic technical structure of a thermal disintegration stage 4 , The thermal disintegration stage consists of a vertical cylindrical container 16 which is surrounded by a plurality of sheaths. The thermal disintegration stage 4 or the container 16 is from a second stirrer shaft 29 pervaded, at the a stirrer 14 is arranged. The wave 29 is at its lower end on a bearing block 18 stored and is arranged with a arranged at the top of the container drive 13 connected via a gearbox. The thermal disintegration stage 4 consists of an inner and an outer jacket, which are made of different materials. The inner jacket 20 is made of stainless steel. The outer jacket is made of conventional structural steel. The inner jacket 20 has a wall thickness of about 3 mm. Also the agitator 14 and the agitator bearing is made of stainless steel. The substrate is introduced at the lower side of the container. On the output side, the substrate is by means of an overflow 32 into the methane stage 5 transported. The parts in contact with the substrate are all inside the thermal disintegration stage 4 made of stainless steel. Zwi outer cylinder and inner cylinder is a heating coil 15 , which is made of a pressure-resistant tube. The coil is traversed by heated water, which comes from the cogeneration unit, not shown here. The outer jacket is made of simple structural steel. This results in an annular space between the inner and outer cylinders, in which the heating coils 15 are located. To the outside, the cylinder is covered with a strong highly effective insulating layer. The remaining annulus is filled with a heat transfer medium, in the simplest case water with antifreeze. The carrier liquid has the task, the heat from the heating coil to the inner shell 20 the thermal disintegration stage 4 transferred to. Since the carrier medium is only acted upon thermally and there is a non-pressurized copy, the production of the container wall can be made with smaller wall thicknesses. In addition, the construction is not carried out according to the pressure vessel regulation. The pressure test refers only to the built-in coils 15 , The material of the coils is normal steel and is used in commercial execution. This advantage also affects the design of the stainless steel parts contacted by the substrate. Due to the non-pressurized outer shell construction, it is possible to carry out the inner shell with low wall thicknesses and thus to reduce the construction costs. The inner jacket 20 the thermal disintegration stage 4 should be made of stainless steel because of the low pH levels in the methane level 5 are given, an increased risk of corrosion within the container can be expected. The operating temperatures are between 70 ° C and 90 ° C. The separation between the stainless steel parts and the structural steel parts is made by means of suitable flange connections. The vertical agitator 14 the thermal disintegration stage 4 is powered by a geared motor 13 , which is located on the top of the container, drives and regulates the fixed bearing side. In the interior of the cylinder is a grid agitator 14 , Since the stirrer shaft 29 in the present case is about 4 m long, it must be stabilized at the bottom of the container by a plain bearing. This sliding bearing can be replaced if necessary by emptying by opening the lower flange. Here is the bearing block 18 welded with a tripod on the lower flange plate of the entire container and can be complete with the flange plate 19 be removed, so that the bearing material in this case PTFE can be replaced with at the same time. The transport of the substrate takes place in a known manner with a screw eccentric pump, which is not shown here and between the methane stage 5 and the thermal disintegration stage 4 is arranged. The thermal disintegration stage 4 is traversed at predetermined time intervals in the so-called batch process, so that the substrate can be subjected to thermal disintegration.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• EP 99968313 [0002, 0004]
• FR 2711980 [0002]
• FR 2711980 A1 [0011]

Claims (28)

Process for increasing the biogas yield of a degradable substrate having at least one hydrolysis step ( 2 ) and at least one thermal disintegration stage ( 2 ), which is arranged between the at least one hydrolysis stage and at least one methane stage, characterized in that by adjusting the individual parameters at least in the at least one hydrolysis stage ( 2 ) the formation of methane gas is prevented. Process according to Claim 1, characterized in that the at least one hydrolysis stage ( 2 ) is operated between 35 ° C and 45 ° C, preferably at 38 ° C. Process according to Claim 1, characterized in that the at least one hydrolysis stage ( 2 ) is operated at a pH between 5.0 to 7.5, preferably between 5.5 to 6.5. Process according to Claim 1, characterized in that the at least one hydrolysis stage ( 2 ) is operated with a FOS / TAC factor between 1 to 4, preferably between 2 to 3. A method according to claim 1, characterized in that the residence time (VWZ) of the substrate in the at least one hydrolysis step ( 2 ) depends on the substrate between 5 hours to ten days. A method according to claim 1, characterized in that the initial substrate in the at least one hydrolysis step ( 2 ) preferably has a TS content of> 30%. Method according to claim 1, characterized in that the thermal disintegration stage ( 4 ) is operated at a pH between pH = 5.0 to pH = 7.5, preferably between 5.5 to 7. A method according to claim 1, characterized in that the residence time of the substrate in the at least one thermal disintegration stage ( 4 ) is between 0.5 to 1.5 hours, preferably between 1.5 to 2.5 hours. Process according to claim 1, characterized in that the FOS / TAC factor in the thermal disintegration stage ( 4 ) is between 1 to 3, preferably between 1.5 to 2.5. Process according to claim 1, characterized in that the residence time of the substrate in the thermal disintegration stage ( 4 ) is between 05 to 3 hours, preferably between 1 to 2 hours. Method according to claim 1, characterized in that the thermal disintegration stage ( 4 ) between 65 ° C to 80 ° C, preferably at about 70 ° C is operated. Method according to claim 1, characterized in that the methane stage ( 5 ) is operated at a pH between pH 7 to pH 8.5, preferably between 7.5 to 8.0. Method according to claim 1, characterized in that the methane stage ( 5 ) is operated at a FOS / TAC factor between 0.2 to 0.4, preferably at 0.3. Method according to claim 1, characterized in that the methane stage ( 5 ) is operated between 45 ° C to 57 ° C, preferably between 50 ° C and 55 ° C. Process according to Claim 1, characterized in that the residence time in the methane stage ( 5 ) is between 20 to 35 days. Method according to claim 1, characterized in that that the concentration of the FOS factor initially between about 15,000 mg / l and in the end about 5,000 mg / l and the concentration of the TAC factor between initially about 5,000 mg / l and at the end is about 15,000 mg / l. Plant for increasing the biogas yield of a biodegradable substrate having at least one hydrolysis step ( 2 ) and at least one thermal disintegration stage ( 2 ) and at least one anaerobic methane ( 5 ) characterized in that between the at least one substantially horizontally lying at least one hydrolysis step ( 2 ) and the at least one methane level ( 5 ) of the substrate at least in its longitudinal axis perpendicular thermal disintegration stage ( 4 ), the individual parameters in the individual stages ( 2 . 4 . 5 ) are optimally adjusted. Plant according to claim 17, characterized in that the longitudinal axis of the at least one hydrolysis step ( 2 ) is arranged substantially horizontally. Plant according to claim 17, characterized in that the stirring shaft ( 2 ' ) (Floating wave) is hollow inside and the cavity is filled with a gas. Plant according to claim 17, characterized in that the diameter of the stirrer shaft ( 2 ' ) depends on the installation between 25 cm and 50 cm. Plant according to claim 17, characterized gekenn characterized in that at least one stirring shaft ( 2 ' ) within the container ( 6 ) of the hydrolysis stage ( 2 ) is arranged. Plant according to claim 17, characterized in that the hydrolysis step ( 2 ) an elongated container ( 6 ), in which at least one horizontal stirrer shaft ( 2 ' ) and at least one heating pipe ( 23 ) parallel to the longitudinal axis ( 21 ) of the container ( 6 ) is arranged, wherein at the stirrer shaft ( 2 ' ) at least one stirring element ( 4 ' ) is arranged and the individual stirring elements ( 4 ' ) are arranged helically on the shaft. Installation according to one of the preceding claims, characterized in that on the stirrer shaft ( 2 ' ) at least one dry storage ( 3 ' ) is arranged. Installation according to one of the preceding claims, characterized in that the stirrer shaft ( 2 ' ) at one end with a floating bearing ( 1' ) and the other end with a fixed bearing ( 5 ' ) is mounted with axial seal. Installation according to one of the preceding claims, characterized in that the floor ( 27 ) of the container ( 6 ) has a slight inclination and in one end region of the container ( 6 ) at least one sand discharge element ( 7 ) is arranged. Plant according to claim 17, characterized in that the longitudinal axis of the thermal disintegration stage ( 4 ) is vertical and the second stirrer shaft ( 29 ) on a bearing block ( 18 ) is arranged. Installation according to claim 17, characterized in that within the thermal disintegration stage ( 4 ) at least two fluid receiving devices ( 15 . 17 ) are arranged, wherein at least one of which is formed like a pipe coil. Installation according to one of the preceding claims, characterized in that the pipe-snake-shaped liquid flow device ( 15 ) of a water jacket ( 17 ) is surrounded.