DE102014001910A1 - Process for the material and energetic utilization of biogenic residues of potato processing and arrangement for carrying out the process - Google Patents

Abstract

Process for the material and energy recovery of biogenic residues from potato processing plants by using the residues in a wet fermentation, by concentrating the total nutrient potential in the form of nitrogen, phosphorus, potassium and sulfur in a fertilizer fraction obtained from the fermentation residues, and by providing the desulfurized biogas for the energetic utilization, characterized in that are used as wet fermentation Hefefermentation for bioethanol production and / or methane fermentation for biogas production, that the resulting biogenic residues from the processing of starchy root crops, such as potatoes, sweet potatoes, cassava, tapioca, cassava, in the form of Peelings, starchy white waters, residues from the purification of feedstocks, sludge from the upstream ethanol distillation, aqueous media from the periodic plant cleaning and / or Sch lambing, that the available residues are subjected to a suspending process that is set using additives with dry matter contents of at least 25% in the biosuspension, a dry matter content between 12 and 18%, that the biosuspension produced is subjected to an aerobic hydrolysis process that the biosuspension hydrolyzate produced an anaerobic fermenter system from at least one hydraulically and partially mixed fermenter with initially used and constantly reproducing special culture is supplied that contained in the recovered feedstock potential of plant nutrients as a mixture of the solid phase of the fermentation residues and from the Hemmstoffentfrachtung the Biofiltrate resulting liquid washing media is obtained with high levels of ammonium and sulfur compounds and that the desulfurized, dried and compressed biogas for the coupled production of electrical shear and thermal process energy is used.

Description

field of use

The invention relates to a method for the material and energetic utilization of biogenic residues of potato processing and an arrangement for carrying out the method. Such a technical solution is needed to increase the security of disposal, to reduce costs, to reduce emissions and to increase the independence of the fossil energy supply in the potato processing industry.

State of the art

Modern production facilities for the processing of potatoes, cassava, tapioca, cassava and similar starchy tubers are operated worldwide with similar process technology. The largest potential of organic and thus high-energy biomass is the entire residue spectrum of a potato processing plant accumulating pest. When dried, this residue is a well-contractual, high-energy, protein-containing and storable animal feed, but in view of rising energy prices barely with alternative protein feed, such as soybean meal or rapeseed cake, can compete. In wet conditions, the peel is used in most cases as a supplementary feed. It is accepted that because of the risk of infection of this excellent microbial soil there is a strong dependency on the decreasing livestock breeders and on a reliably functioning transport logistics. The organic residues not suitable for animal feed must generally be disposed of as waste, although they also have considerable energy potential and plant nutrient content. Examples are known in which, in order to avoid dependencies of animal breeders close to the location, the resulting residues are applied to farmland as soil improvers. In order to avoid damage to the soil life, because of the possible crusting of the soil surface due to the starch contents, the applied residues must be incorporated immediately into the culture layer. At the same time, potato processing is burdened to a considerable extent by rising energy prices.

This is another reason why the operators of potato processing plants are very interested in the industry because of the competitive pressure in the industry. Despite this situation, no example has been made so far in industrial practice, according to which the predominantly moist biogenic residues from the SKA processing would be a material and energy recovery would have been supplied. From a material and energetic utilization of the accumulating residues could be spoken, if waiving the thermal drying by wet fermentation in addition to the complete receipt of plant nutrients from the at least 22% dry biomass in the wet peelings biogas with a calorific value of at least 1,140 kWh / t, of which at least 450 kWh / t electrical energy would be gained. Known technical solutions are limited to the utilization of biological sludges from wastewater treatment by means of methane fermentation, whereby only comparatively small amounts of the actually available potential are used. Both the practically uninterrupted residual materials and the almost constant energy demand for electric energy, thermal energy and cooling energy, as well as motor fuels form almost ideal conditions for the use of methane fermentation for energy production from renewable sources and concurrent utilization of the resulting fermentation residues for fertilizer production. Therefore, there has been no lack of attempts to further develop the state of the art that, using the biogenic residues in particular contributions to reduce the fossil energy needs of a potato processing plant can be made. The peculiarities of the biogenic residues from the industrial potato processing consist in the fine graininess and in the continuity of the seizure of these residues. The barriers to the use of these residues in biotechnological recycling plants obviously include the considerable contents of proteins and / or raw fibers, which are supposed to counter monofermentation, whether in the context of yeast fermentation for ethanol production or methane fermentation for biogas production.

The DE 3627253 C2 (1986) describes, for example, a method for the biological treatment of substrates containing organic substances, wherein the central treatment stage for the solids-depleted phase of a biosubstrate and the solids-rich phases of the biosubstrate liquefied in subsequent treatment steps comprises a hydrolysis reactor for the aerobic degradation of the organic substances contained in the biosubstrate is.

However, the solution described gives no indication of the treatment of the resulting hydrolysis gases, which are known to also contain fatty acid vapors from the aerobic decomposition of selected phases of the registered biostats. The discharged from the hydrolysis substrate return to a part without further pretreatment in the hydrolysis. The remaining solids-rich phases are separated after several intermediate treatments of remaining undissolved constituents and removed from the further fermentative treatment. The alleged suitability for the utilization of known solid-high production residues from the potato processing is not given for lack of available adapted Methanbakterienkulturen and lack of culture-preserving fermentation technology for the disclosed technical solution.

Furthermore, with the DE 4000834 C2 (1990) published a technical solution for the biomethanization of organic residues from breweries, which could in principle also be applied to potato processing residues. It provides for the wastewater to be added to the usual residual materials from the immediate production process and for the wastewater, which is now subjected to extremely high levels of organic pollution, to undergo a multi-stage fermentation process. The disclosed method makes use of cascaded loop reactors, which are at least partially filled with random packings and completely mixed by compressed process gases. The perceived need for hydrolytic pretreatment in a first fermentation stage is said to be met by chemical, enzymatic and optionally by aerobic to anaerobic means. Obviously, in the interests of energetic development of predominantly lignocellulosic and protein-containing pulp ingredients, these should preferably be used after comminution to <1.0 mm. The process described assumes the possibility of being able to extract a pure water by ultrafiltration from the fermentation residues of the last anaerobic treatment stage which, however, should at the same time be the source of an additional degassing process. A refining step should be used for further solids reduction and an aerobic aftertreatment step for odor elimination and nitrogen reduction. The theoretical approach of this proposal contradicts in many respects often confirmed practical experience and could logically no input into the modern potato processing technology.

Thus, it is generally known that it is fundamentally not possible to obtain sufficiently stable available, in completely mixed fermenters, a special bacterial culture suitable for the utilization of the lignocellulosic and protein-rich starting materials. However, the acknowledged requirement of prehydrolysis of biosuspensions with potato processing residues can only be met by enzyme addition or by anaerobic treatment if additive costs are not an issue, or if large volume additional anaerobic systems are available. In the proposed technical solution, the aerobic nitrogen reduction of the digestate after the multi-stage fermentation process is used exclusively for the recovery of low-polluted wastewater at the expense of recycling the reduced nitrogen load into the atmosphere. On the other hand, eluates from individual fermentation stages should be recycled to other fermentation stages to control optimal C-N-P ratios in the respective fermentation substrates. Thus, a key condition for maintaining a sustainable fermentation process is ignored, according to which delousing the closed fermentation system of nitrogen and sulfur compounds to avoid the formation of toxic concentrations of these compounds in the fermentation substrate is indispensable. This is especially remarkable, because in the form of the peelings from the potato processing protein and thus nitrogen and sulfur rich substrates are introduced into the fermentation process.

The DE 4226087 A1 (1992) describes inter alia a method for the biological treatment of organic substances, in particular for anaerobic biological hydrolysis for subsequent biomethanization. The disclosed technical proposal seeks to solve the problem simpler and more efficient to design the methods known from the prior art and in particular to provide a control concept by which the pH, the solids concentration and the Feststoffverweilzeit are independently adjustable. The essential means of this technical solution are that in a first anaerobic hydrolysis step, the predominantly dissolved organic constituents of a biosuspension and in a second anaerobic stage a solids-rich fraction of the biosuspension to be treated are hydrolytically acidified so that in a third treatment stage, both hydrolyzates undergo methanation can be. Even with these proposals, it is not possible for many reasons, the process of material and energy recovery of potato processing residues with the required energy efficiency and stability to lead.

Neither can be effectively treated with the proposed procedures, the actual and temporally possibly changing residual flow of a potato processing plant because of the required pH control, still stands before the methanization of the anaerobic process rejectable solids fraction available for further energy use. In addition, any preconditions for limiting the levels of nitrogen and sulfur compounds in the fermentation substrate to concentrations below the toxicity threshold are lacking if the system is to be supplied with high-protein potato peelings.

The DE 19613397 C2 (1992) describes a process for the biological purification of wastewater, which differs from the prior art available at that time, in that the biosuspension to be treated in the form of a waste water is first subjected to a phase separation, wherein only the solids-rich phase is fed directly to the fermenter. The low-solids phase from this process stage is to be fed to an ammonia stripping, although in the case of the peelings from the potato processing, the nitrogen inventory is known to be predominantly present in protein form and ammonium is formed from it only by the anaerobic fermentation process. According to the proposed technical solution, the described attempt at nitrogen discharge certainly does not serve to avoid nitrogen enrichment up to toxic concentrations in the fermentation process. The aerobic hydrolysis of the effluent from the ammonia stripping thus has virtually no influence on the required dissolution of the lignocellulose composite and on the development of the energy potential of the lignocellulose-containing residues from the potato processing introduced with the peelings.

With the DE 19615551 C2 (1996), inter alia, a technical solution is described, which serves the multi-stage treatment of biomass for the production of biogas. The developed method is intended to solve the problem of achieving a maximum reduction of the cell contents of the biological waste with a minimum investment and operating costs. In the case of short residence times of the biomass in the anaerobic environment, an economically usable gas mixture of methane and carbon dioxide must be obtainable, whereby the amount of biogas to be maximized and the post-rotting fermentation compost quantity to be minimized.

For this purpose, the feed should first be freed of non-biodegradable by-products by screening and metal deposition and processed by post-shredding. Thereafter, the incipient acidification should be intensified by intermediate buffering of the fermentation substrate to be treated in a prehydrolysis tank. For the purpose of increasing the attack surfaces for the microorganisms is intended to effect the dissolution of the cell structures by ultrasonic treatment. This is followed by the production of a biosuspension by mixing the fermentation substrate with process water containing active biomass in a static mixer. Now, the biosuspension produced at temperatures for the mesophilic degradation process with the addition of air is subjected to an aerobic hydrolysis treatment. It should come despite the introduction of air to a sink-float separation and the expulsion of hydrogen sulfide. Now the resulting liquid phase is heated with the containing organic acids to temperatures for thermophilic cultures and fed to the methane reactor with the addition of further process water. The solid phase which obviously arises in the hydrolysis vessel is dehydrated, fed to a post-rotting unit or hydrolyzed again. It is worth noting the proposal to interpret the methanization so that the individual fermentation tanks are each designed only for receiving a daily amount of the resulting feed, so that the postulated residence time can be guaranteed, because short-circuit currents are reliably avoided. The careful complete circulation of the fermentation substrate in the fermentation tanks is ensured by avoiding so-called dead zones by recirculated injected biogas. Likewise, as in the case of the hydrolysis vessel, the solids which have not been completely degraded are removed from the methane reactor by means of a discharge screw, dewatered and post-aerobically retted. The aqueous fractions of the fermentation residues are decanted, collected in a process water tank and used from there as a heat carrier and mashing water for the hydrolysis or moistening the Nachrotteeinheit and the biofilter. The proposed method is obviously designed for the disposal of biogenic waste materials and, for several reasons, not suitable for the efficient recycling of energy and potato residues from potato processing. Although a multi-stage aerobic prehydrolysis of the suspended biomasses is provided, however, neither measures to prevent toxic concentrations of nitrogen and sulfur compounds in the fermentation medium are provided, as they are indispensable for the use of particularly protein-rich residues from potato processing.

Furthermore, the initially undissolved portions of the biomasses used, as are typical for peelings from potato processing in the form of proteins and / or lignocellulosischen portions of Schalmaassen, discharged as sinking and / or floating sludges from the individual process stages and after dewatering a fed to aerobic rotting. The aerobic decomposition primarily requires process energy and leads to the loss of appreciable portions of the contained inventory of fertilizer nitrogen and sulfur compounds. A special for the fermentation of Bacteria culture adapted to lignocellulosic biomass is neither available nor is it intended to be used and could not be obtained and reproduced even in the respectively thoroughly mixed fermentation tanks.

The DE 10 2004 030 482 B4 (2004) describes a process for the treatment of waste water from the processing and treatment of organic waste. This technical solution contains, inter alia, the suggestion to add at least a portion of the organic feedstock not to the fermentation stage, but only the first preferably mechanical phase separation of the resulting digestate as flocculant the so-called turbidity of this process stage, thus one for the intended downstream membrane filtration stages to achieve a suitable course of action. The proposal also includes the advice to provide the proposed reverse osmosis a liquid phase, which allows both the formation of acidic ammonium compounds by acid addition and obstructs the release of ammonia. Finally, the actual fermentation process before the build-up of toxic ammonium concentrations in the fermentation substrate should be protected in that concentration dilution of inhibitors for the fermentation process is achieved by addition of reverse osmosis permeate as Ansetzwasser in the production of a fermentable biosuspension. This technical solution does not meet the requirements for the material and energy recovery of residues of the potato processing process, especially since the high-energy solid phases of the organic waste to be recycled are discharged from the biotechnological energy production process early and partly without any fermentative treatment.

That in the magazine Brewery Forum, issue 9/2000, under the title "Grain Fermenting to Biogas" described method provides for the addition of up to about 15% spent grains to other residues of crop production and the food industry.

Such a method should also be suitable for peeling masses because of the qualitative similarity of brewing solids and residues from potato processing. In the process chain described process steps for the avoidance of concentrations of so-called inhibitors in the fermentation process are not provided. The feed mixture is first sanitized for one hour at 70 ° C and then hydrolyzed using acidification bacteria. The hydrolyzate produced is then treated in methane fermenters. According to the description of the technique used, there is no media recirculation, the resulting fermentation residues are used either untreated fertilizer technology or processed in his own wastewater treatment plant to flooding wastewater and a solid matter rotting material.

The DE 10 2007 004 135 A1 (2007) identifies a method and a device for the fermentation of biomass and should expressly be suitable for the utilization of organic residues from the brewing process, whereby it would also have to be usable for the utilization of moist residues from the potato processing in an actual existing suitability. The developed proposal provides for the use of a the anaerobic fermenter system downstream stack container for the resulting fermentation residues, where the digestate membrane technology part of the aqueous phase should be withdrawn to return the remaining partially dehydrated substance in the fermentation process again. This proposal contains neither a solution for the use and the sustainable reproduction of an adapted culture for the lignocellulose-containing residues nor measures to avoid overloading the fermentation stage with nitrogen and sulfur compounds, the formation of which is unavoidable when using highly proteinaceous residues from the potato processing process. The multiple treatment of at least part of the solids fraction used as a helpful measure in no way leads to the required energy yields due to the lack of targeted hydrolytic treatments.

The DE 20 2008 014 330 U1 (2008) describes a device for supplying energy to a brewery, which, among other things, means for the hydrolysis and fermentation of brewery solids. Such a technical solution must be equally suitable for a potato processing plant because of the similarity of the resulting residues.

The object to be solved by the proposal according to the invention, however, is to improve the energy supply. This is to be achieved primarily with the coupling of different techniques for the production of electrical and thermal energy from renewable sources. The proposal preferably provides for separate hydrolysis for each of the available feedstocks without indicating the nature of the hydrolysis. The aqueous substrates obtained after the hydrolysis stages are then removed from the solid phases and kept away from the further biotechnological process. The fermentation stage, only the comparatively low-energy solids-depleted media to be supplied without giving any indication as the dissolved in the fermentation substrates nitrogen and sulfur compounds from the Use of high-protein residues to be treated before concentration in the fermentation process.

The DE 10 2008 060 140 A1 (2008) describes a Biertreber hydrolysis process, which would have to be suitably suitable for potato processing in principle because of the material similarity of the spent grains with the peeling masses from the potato processing process. It plans to first mix the available proteins and lignocellulose-rich residues with wastewater and sludge and to feed them into a first hydrolysis process. The hydrolyzate produced is then to be separated in a phase separation in a high-solids and in a low-solids fraction, wherein the high-solids fraction is subjected under liquor use a solids digestion. The resulting from the liquor digestion medium is then fed again to a phase separation and subjected to the recovered solids-rich fraction in a second hydrolysis process again a liquor digestion. After renewed phase separation, the low-solids fraction is to be fed to a third hydrolysis stage, while the solids-rich fraction is optionally dried with other biogenic residues and compacted for subsequent combustion. The resulting from the third stage hydrolysis substrate is finally fed to a fermentation process. A special starter culture, which preferably has to be taken from parallel plants or grown specially in small plants, should already be used in the first hydrolysis stage, which is also preferred to be operated at 60 ° C.

Obviously, anaerobic hydrolysis processes are used in which the active bacterial cultures produce the necessary acidification enzymes themselves. For the fats, proteins and carbohydrates used with the residues, the hydrolytic pretreatment is not required per se, at best for the accelerated process control in the fermentation stage. The regular neutralization of the more or less acidic hydrolyzates from the individual stages of hydrolysis by addition of alkali does not appreciably lead to the result that the lignocellulosic material components used in particular with the residues are digested for the subsequent fermentation process. These high-energy components from the residual materials used can be found with a high degree of certainty in the high-solids fraction to be discharged after the second hydrolysis stage and hardly contribute to the energy gain for the potato processing process with significantly more than 70% moisture content after energy-intensive drying. Even if a starting culture which supports the hydrolysis process is available, it can scarcely support the methanation process in the downstream fermentation stage at the stated temperatures of 60.degree. C., because the microorganisms required therein either in the temperature range between 30 and 40.degree. C. as mesophilic culture or in the temperature range between 48.degree and 55 ° C as thermophilic culture are known to have other compositions.

With the DE 10 2010 005 818 A1 (2010) announces an energetically optimized process for operating a bioethanol production plant. Such a method is therefore part of the search range of a person skilled in the art, because both the vapors from a bioethanol production and the peeling masses from the potato processing are equally aqueous substrates with predominant protein and lignocellulose contents. When seized, the peelings have a higher dry matter content than the ethanol sebum. According to the stated task, the proposed proposal only makes statements that the vapors produced in the bioethanol production process are fed into a methane fermentation.

There, the dissolved organic compounds contained in the vinasses would be converted predominantly to biogas and thus the aqueous phase of the digestate can be used at least partially for the substitution of the required fresh water for the mashing process. In order to avoid an additional burden on the mashing process of the ethanol plant, the solids-rich phase should be withdrawn from the recycled digestate before reuse. A concentration of dissolved hydrogen sulfide and ammonium in the recirculated digestate should be prevented by appropriate depletion steps. Further information can not be found in the above proposal.

Summary Criticism of the Prior Art

The technical solutions hitherto disclosed have the common deficiency that a mono-fermentation of the biogenic residues from the potato processing with the required biotechnological stability and without considerable addition of diluents, such as fresh or waste water, can not be guaranteed. In addition, appropriate proposals for effective preparation of high-energy lignocellulosic fractions of the available potato processing residues for biogas production have not been disclosed. Finally, the previously published sources also no usable Note how the high protein contents of the peeling masses from the potato processing and the resulting system load of the nitrogen and sulfur compounds acting as inhibitors for the biotechnological process can be counteracted. Consequently, none of the proposals made so far has found its way into industrial potato processing.

Object of the invention

The object of the invention is therefore to overcome the deficiencies of the known technical solutions to problems. In particular, technical, logistical, energetic and ecological improvements are to be made possible with the help of the invention in the potato processing, which should lead to a sustainable cost reduction and improved competitive positions. The desired independence from the fossil energy market on the one hand and from the conventional feed market on the other hand is considered a prerequisite for stable and predictable potato processing.

In particular, the exclusive material and energy recovery of the resulting in a potato processing plant biogenic residues with high energy and ecological efficiency should be possible. High reliability should be ensured by avoiding interfering influences on the biotechnological process.

Description of the invention

The object is achieved according to the invention according to the teachings of claims 1 and 11. Advantageous embodiments of the invention are described in the subclaims. Thereafter, the material and energy recovery of biogenic residues from potato processing plants by using these residues in a wet fermentation for biogas production takes place. As a result of the extensive conversion of the carbon compounds contained in the residues to biogas, a considerable concentration of the nutrient potential, in particular in the form of nitrogen, phosphorus, potassium and sulfur, is effected in a fertilizer fraction obtained from the fermentation residues. The biogas formed in the fermentation process is available for energy recovery after almost complete removal of entrained hydrogen sulfide and water vapor. The resulting in the potato processing biogenic residues, such as peelings, white waters, residues from the purification of feedstocks, aqueous media from the periodic plant cleaning and / or sludge from the operational wastewater treatment are in the respective seizure state without further pretreatment and, if required, without intermediate storage a suspending process subjected. Through the use of qualitatively similar additives with dry matter contents of at least 25%, for example, grain cleaning residues u. Like. And / or process waters, a dry matter content is set between 12 and 18% in the produced biosuspension. The biosuspension produced is then subjected to an aerobic hydrolysis process. Not only the desirable acidification processes, but also the at least partial cleavage of the lignocellulosic ingredients of the biosuspension are achieved. The obtained hydrolyzate passes into an anaerobic fermenter system, which consists of at least one hydraulically and only partially mixed fermenter. This fermenter system is equipped with an initially used and constantly reproducing special culture.

• – im Einsatz einer speziellen auf die Verwertung von protein- und lignocellulosereichen Bioabfällen adaptierte Methanbakterienmischkultur,
• – in der Anwendung einer Fermentertechnik mit der Eignung zum uneingeschränkten Erhalt bzw. zur stetigen Reproduktion der eingesetzten Startkultur,
• – in der Rückführung eines Teiles der Fermentationsreste in die Suspensionsstufe, verbunden mit der wiederholten hydrolytischen und fermentativen Behandlung des in den rückgeführten Fermentationsresten enthaltenen biogenen Potentials,
• – in der Schaffung einer zusätzlichen Hemmstoffsenke zur Vermeidung einer Aufkonzentration von Ammonium und Schwefelwasserstoff in den Gärsubstraten auf Werte in der Nähe der toxischen Schwellwerte und
• – in der Nutzung der die entfrachteten Hemmstoffe enthaltenden Waschflüssigkeit der Hemmstoffentfrachtungsstation als flüssiges Düngerkonzentrat.

The potential of plant nutrients contained in the recycled feedstocks as a mixture of the solid phase of the fermentation residues and the fertilizer concentrates obtained in the Hemmstoffentfrachtungsstation with high levels of ammonium and sulfur compounds are completely recovered and recycled to the economic cycle as organic NPKS fertilizer. The biogas produced in the fermentation process is desulphurised, dried and, if necessary, compressed. In this quality, it is preferably used for the coupled production of electrical and thermal energy. Thus, the function of the proposed method results both from the direct coupling of known process steps, such as production of a biosuspension from the available residues of potato processing in each seizure condition and in the respective amounts without previous intermediate stacking, supply of qualitatively similar waste materials from agriculture or the food industry as a welcome cofermentate, pretreatment of the produced biosuspension in a lignocellulose-splitting aerobic hydrolysis, biological gas desulphurisation to obtain a sulphurous bioacid required in the recycling process, as well as from newly developed process steps. Such process steps exist

• - using a special methane bacteria mixed culture adapted to the recovery of protein and lignocellulosic biowaste,
• In the application of a fermenter technique suitable for unrestricted preservation or continuous reproduction of the starting culture used,
• In the recycling of part of the fermentation residues to the suspension stage, combined with the repeated hydrolytic and fermentative treatment of the biogenic potential contained in the recycled fermentation residues,
• - in the creation of an additional inhibitor sink to avoid concentration of ammonium and hydrogen sulphide in the fermentation substrates to values close to the toxic thresholds and
• In the use of the scrubbing liquid containing the defoamer inhibitors of the inhibitor decontamination station as a liquid fertilizer concentrate.

In a preferred embodiment, at least portions of the sour mashes produced in the case of the preceding yeast fermentation in the form of solids-rich presscakes or the vats of the biosuspension obtained in the ethanol distillation of the sour mash are added.

In another embodiment variant, additional biogenic potential in the form of the sludge fraction is obtained from the aerobic and / or anaerobic treatment of the production effluents of the potato processing plant and fed to the suspending process. This not only reduces the wastewater load of the potato processing plant, but also reduces odor emissions and increases the production of renewable energy from its own biogenic sources.

Another solution variant is to stabilize the entire process by increasing the dry matter content of the biosuspension to values of more than 14%. For this purpose, additives of a composition similar to the residues of potato processing, such as malt dusts, grain chaff, mill dusts and / or brush dusts from grain cleaning, should preferably be used in the suspending process. In addition to process stabilization, the biogenic potentials contained in the additives are tapped simultaneously with almost undiminished efficiency for the production of process energy for the potato processing process.

Advantageously, the proportions of the fermentation residues obtained during the mechanical phase separation of the fermentation residues biofiltrate recycled as process water in the suspension process. Because of the comparatively high feed rates of proteins contained in the residues of the potato processing, the biotechnological utilization process of these residues is endangered by excessive ammonium and hydrogen sulfide contents in the fermentation substrates as soon as a required reduction in concentration can not be guaranteed. In accordance with the invention, those biofiltrates from the fermentation residues are used for this purpose, which have previously been deprived of portions of the nitrogen and sulfur compounds contained in an inhibitor-deflagration process. On the one hand, this eliminates risks to process stability and, on the other hand, it supplies the extracted inhibitors as valuable plant nutrients for fertilizer use.

In a further advantageous embodiment of the invention, the biofilate parts of the dissolved ammonium and / or dissolved hydrogen sulfide in an expeller at up to 65 ° C elevated temperatures and at a pressure in the supernatant fumes of at most 980 mbar to withdraw. The ammonia and / or hydrogen sulfide-containing vapors produced in the generator are then cooled in an intermediate heat exchanger to a maximum temperature of 45 ° C. The cooled vapors containing ammonia and / or hydrogen sulfide are now fed to a downstream vapor scrubber in the form of a trickle body apparatus, with sulfurous bios acid from biogas desulfurization having a maximum temperature of 25 ° C. and a pH of between 1 and 3.5 being used as the scrubbing medium. In the scrubbed sump, in particular due to the incorporation of ammonium into the scrubbing medium, a continuous increase in its pH value takes place, whereby the scrubbing efficiency is simultaneously reduced. When the selectable upper limit for the permissible pH range is reached, the scrubber sump is taken off a proportion of between 10 and 60% and used as a fertilizer concentrate with high nitrogen and sulfur concentrations. The withdrawn amount of washing liquid is then replaced by fresh sulfurous bioacid from the gas desulphurisation process.

For the desired high energy efficiency of the method according to the invention, the special hydrolysis process is essential. In a preferred embodiment, the hydrolysis process is carried out with intensive mixing with ambient air in a stirred tank at temperatures between 50 and 60 ° C. In this case, ambient air in the order of between 2 and 10% by volume of the biogas obtained in the entire fermentation process is added to the hydrolysis process. The dimension of the hydrolysis vessel (s) is chosen such that a mean residence time of the biosuspension in the hydrolysis vessel of about 2 days can be maintained. The hydrolytic treatment is effectively assisted when the hydrolysis process between 20 and 100% of the biological desulfurization of the biogas accumulating sulfurous bioacid is added. Since the gaseous reaction products released during the hydrolysis also remain in the gas system, the ambient air supplied to the hydrolysis process also serves to supply the aerobic sulfur bacteria in the gas desulphurisation process. Odor emissions, especially in the form of fatty acid vapors resulting from the hydrolysis, are safely excluded.

It is possible to compress the resulting hydrolysis gas to at least 30 mbar and to introduce it into the central crude gas line before the gas desulphurisation station.

In another embodiment, the resulting hydrolysis gas can be compressed to at least 30 mbar in order to then supply it to the corrosion-resistant secondary fermenter station. Overcoming the pressure loss of the gas desulphurisation station does not require any additional gas conveying technology in this case. The hydrogen and carbon monoxide components contained in the hydrolysis gas as well as the expected fatty acid vapors are incorporated in the biogas formation either in the anaerobic digestate storage and / or in the secondary fermenter station. The Methanbacteria mixed population to be used initially as a starting culture for the fermentation process is obtained with the addition of predominantly lignocellulosic starting materials in a breeding station for mesophilic or thermophilic mixed cultures. In the case of the so-called "tipping over" of the fermentation process which can only be imagined in the case of extreme violations of the prescribed operating regulations, the fermentation process can be restarted using the breeding station and continued without noticeable reductions in yield.

• – einer Suspendierstation,
• – einer Fermentationsstation für die Methanfermentation,
• – einer Phasentrenntation für die Garrückstände,
• – einem Biofiltratsvorratstank und
• – einer Gasentschwefelungsstation.

The proposed arrangement for carrying out the method according to the invention consists of at least

• - a suspending station,
• - a fermentation station for methane fermentation,
• - a phase separation for the cooking residues,
• - a biofilter stock tank and
• - a gas desulphurisation station.

According to the invention, the suspending station is connected to a storage and dosing system for additives rich in dry substances. Further, an inhibitor dump station is disposed between the biofilter stock tank and the suspending station. For gas desulfurization, a gas scrubber is preferably arranged in the form of a trickle apparatus. For storing the sulfurous bioacid obtained in the gas desulphurisation station, a biosäurevorststank is arranged between the gas desulphurisation station and the Hemmstoffentfrachtungsstation and / or the Hydrolysestation. Finally, a hydrolysis station is arranged between the suspending station and the fermenter station. It is essential to the invention that the fermentation station consists of at least one main fermenter and at least one downstream secondary fermenter.

With this arrangement of the plant components is achieved that without special crushing, storage, dosing and mandatory continuous feed processes for external media, such as chemical and / or biotechnological additives and / or dilution media for suspending, a stable material and energy recovery process for the resulting Residues of potato processing can be maintained. With the subdivision of the fermentation process on a main and on a Nachfermenterstation, can easily be taken into account a major concern. This is that the inevitable arising in changing composition residues from potato processing are first treated after previous hydrolysis in the main fermenter station with a relatively robust mesophilic culture. Thereafter, the further fermentation of the fermentation substrates leaving the main fermenter station can be carried out with significantly lower quality differences in the main parameters by the more efficient but less robust thermophilic cultures. For the permanent preservation of the starting structure used with particular suitability for the protein and lignocellulosereichen residues of potato processing, it is essential to the invention that at least one or the main fermenter are hydraulically mixed and not completely mixed apparatus.

Advantages of the invention

The advantages of the invention consist, after the economic effects, primarily in the reduction of process energy costs for the operation of potato processing plants. By largely covering the thermal process energy demand from the operation of combined heat and power plant technology for the energy recovery of the recoverable biogas, additional sales can be achieved by selling surplus quantities of electric energy. In any case, a partial or complete independence of the Operation of potato processing plants has achieved price developments in the process energy market from fossil sources. The logistical and contractual dependence on the resulting peelings exploiting animal producers is completely avoided because of the virtually impossible storage capacity of these nutrient-rich and thus extremely vulnerable to infection feed. The resulting solid fermentation residues from the phase separation can be sold as nutrient-rich organic NPKS (nitrogen-phosphorus-potassium-sulfur) fertilizers for additional sales.

The avoidable disposal of waste, such as sludges from the operational wastewater treatment or loaded filter aids, leads to noticeable cost reductions in the process of potato processing. In the case of the sale of certificates from the saved emissions of CO ₂ equivalents, additional revenues are generated. The pollution-relevant plant-related load traffic is significantly reduced. In addition, encounters between feed and waste transports on the one hand and food transports on the other hand can certainly be avoided. The odor emissions resulting from the temporary storage and transport of animal feed and biogenic waste can be safely avoided. The waste water load, which is often a limiting factor for the potential expansion of production, can be reduced when introduced into public sewage treatment plants. Finally, the use of so-called "green" energy can be promoted to promote the acceptance of the products produced.

embodiment

The invention will be explained in more detail below with exemplary embodiments. In the attached drawing show:

1 the process scheme of the technical solution according to the invention;

2 the process scheme of the technical solution according to the invention with an upstream Bioethanolgewinngsstätte for utilization of the carbohydrates contained in the residues;

3 the block diagram for the interaction of the system components in the direct use of the resulting peelings in the suspending station;

4 the block diagram for the interaction of the system components when using the solid phase from the phase separation of the resulting peelings in the suspending station;

LIST OF REFERENCE NUMBERS

1

Home Culture

2

Potato processing plant (supplier of ethanol vapors, peelings, whitewater, residues from the purification of feedstocks, organically contaminated cleaning agents)

3

Storage for suspension additives (malt dusts, grain chaff, Dicksauermaische, mill after-products)

4

operational wastewater treatment plant (supplier of sewage sludge)

5

Hemmstoffentfrachtungsstation

6

Suspendierstation

7

hydrolysis station

8th

main fermenter

9

fermenter

10

digestate

11

Phasentrermstation

12

Biofiltratvorratstank

13

fertilizer warehouse

14

Gasentschwefelungsstation

15

Biosäurevoratstank

16

gas storage

17

energetic gas utilization complex

Example 1:

According to the 1 and 3 become available biogenic residues from a potato processing plant 2 , in particular the peelings, the white waters and the sludges from the operational Wastewater treatment plant 4 , according to their attack in the potato processing process predominantly by means of pipeline transport of a suspending station 6 fed.

In the example will be off
1 part by weight of peeling mass with 22% dry matter content and 94% organic content of the dry matter,
0.012 parts by weight of sediment from the so-called white waters with 15% dry matter content and 98% organic content of dry matter,
0.015 parts by weight of sludge from the operational wastewater treatment with 28% dry matter content and 65% organic content of the dry matter and
0.21 parts by weight of thickened sludge from the flotation of the resulting biofiltrate with 10.1% dry matter content and 96% organic content of the total dry matter using recycled biofiltrate
1.648 parts by weight of biosuspension with 15% dry matter content and 93.7% organic content of the dry matter.

In a warehouse for suspension additives 3 additives such as malt dusts, hop dusts and / or grain cleaning residues, with an average dry matter content of at least 85% and at least 80% organic content of the dry matter stored. In the case of increased seizure of waste fractions from the potato processing plant 2 with smaller dry mass fractions, the preferred dry matter concentration in the biosuspension to be prepared batchwise is adjusted between 12 and 18% by mass by admixing these additives. The generated biosuspension is then in the Hydrolysestation 7 pumped and subjected to an aerobic hydrolytic treatment. In this case, the hydrolysis tank ambient air in the amount of about 10%, based on the biogas volume to be desulfurized fed. In the hydrolysis tank, additional heat energy is supplied via heating surfaces integrated in the container wall. By the action of the exothermic hydrolytic reactions and the heat energy indirectly supplied to the hydrolyzate by heating water is in the Hydrolysestation 7 maintain a temperature between 55 and 60 ° C. The mean residence time of the biosuspension in the hydrolysis station 7 is at least 2 days. The added ambient air is pressed in fine bubbles above the container bottom into the hydrolysis tank. The hydrolysis tank also has a centrally positioned propeller agitator, with the aid of which not only an intensive and degassing turbulence is maintained in the upper region of the hydrolysis tank, but also the exiting oxygen-containing gases are repeatedly brought into contact with the biosuspension via the generated trumpet. The acidification process in the hydrolysis tank, which leads to a lowering of the pH of the biosuspension from about 7.5 to less than 4 for the hydrolysis station 7 leaving hydrolyzate is assisted by the addition of the available bioacid. The resulting oxygen-containing hydrolysis gas is detected in the head of the hydrolysis tank, compressed by means of a booster blower to about 50 mbar and conveyed into the crude gas line. The use of oxygen-containing ambient air in the hydrolysis process, the optionally introduced into the biosuspension anaerobic microorganisms are so permanently damaged that in the main fermenter 8th active methane bacteria mixed culture remains safely protected from displacement. That in the hydrolysis station 7 produced hydrolyzate is removed from the hydrolyzation tank through the metering pump station and the main fermenter station 8th fed.

The hydrolysis tank thus also serves for the process decoupling between the batchwise production of the biosuspension in the suspending station 6 and the quasi-continuous feeding of the main fermenter 8th , For the dosing pump station, the hydrolysis tank also serves as a pump reservoir. With the help of the dosing pump station, the so-called feeding of the individual main fermenters takes place 8th the main fermenter station. At a time interval of four hours each fermenter 8th fed to the main fermenter each one-sixth of the intended daily dose of hydrolyzate. During the commissioning of the recycling plant for the biogenic residues of the potato processing plant, the main fermenter station was filled with biomass that had a mesophilic starter culture 1 from an already existing recycling plant for potato processing residues or from an active fermenter operation for the biotechnological utilization of predominantly lignocellulosic feedstocks, for example grain cleaning residues, oilseed cleaning residues, brewery waste, ethanol bottoms and / or pulps from starch production. The two main fermenters used in the main fermenter station 8th are hydraulically mixed devices, which are operated in the push-through principle. They contain three areas with different demands on the biomass used. A first subarea is flow-mixed at regular and selectable time intervals. An intermediate, non-intermixed area is designed as a short-circuit preventing plug and serves as a starting culture 1 used biomass for undisturbed reproduction. A third section is located above the so-called plug area and includes the part of the main fermenter 8th located fermentation substrate, which is located directly at the end of the fermenter. This area also flows after reaching the full mixing pressure the biogas formed in the first area and leads to an intensive and turbulent mixing of the largely degassed fermentation substrate. At the same time, the fermentation substrate present at the outlet is fluidized so effectively that the formation of floating layers, by which the gas release and / or the course of the fermentation residue could be impeded, is reliably avoided.

The metered hydrolyzate batch reaches the first fermenter area.

There, the fermentation substrate is in each case after completion of the dosing by means of short-term pressure equalization between the gas space above the flow-mixed fermenter of a maximum of 490 mbar and above the unmixed plug area at the end of the fermenter of 50 mbar is offset by the mixing pulse thus effected in a circular flow. At the same time, in this process, part of the mesophilic biomass growing under ideal conditions in the non-thoroughly mixed graft is conveyed back into the flow-mixed fermenter area. This also brings a particularly low-germ biomass, such as the peelings from a potato processing plant, in the fermentation process early in contact with active and already adapted methane bacteria mixed culture. During the metering of a batch of hydrolyzate in the first fermenter area, an adequate volume of fermentation substrate, reduced by the mass of biogas released since the previous metering into the fermenter station, is discharged via the outlet of the fermenter. Thus, there is virtually no significant change in the filling volume of the fermenter during the entire life of the fermenter. The effluent of the fermentation substrate from the two main fermenters charged with hydrolyzate 8th now passes to the postfermenter for post-treatment 9 the post fermenter station. The secondary fermenter 9 is similar to the main fermenter 8th constructed. However, he has two peculiarities:
First, it is operated with a maximum mixing pressure of 420 mbar, which is for the flow mixing of the first fermenter section in the secondary fermenter 9 only about a 15% reduced mixing energy is available. This is unproblematic, taking into account the reduction in the dry matter content of the fermentation substrate that has already taken place in the main fermenter station. However, this can drain the fermentation substrate from the main fermenters 8th practically at any time in the secondary fermenter 9 reach.
Secondly, after passing through the main fermenter station, the fermentation substrate is evened out so far as to contain the biogenic components that the secondary fermenter 9 can be operated stably with an adapted thermophilic bacterial culture, without overstraining the less robust thermophilic bacteria by strongly changing qualities of the fermentation substrate. With this arrangement of anaerobic treatment steps connected in series by means of mesophilic and thermophilic bacterial cultures, the changing composition of the in the potato processing plant 2 accumulating biogenic residues without accepting the risk of overloading the biotechnological system.

At the same time, because of the minimum holding time of the fermentation substrate in the secondary fermenter station at temperatures for thermophilic bacterial cultures, the requirements for effective sanitation of biogenic waste are met if, for example, they are to be marketed as organic fertilizers after biotechnological treatment. The Nachfermenterstation is a digestate storage 10 downstream, which primarily serves to decouple the 9 process stages fermentation and phase separation. The digestate warehouse 10 is covered with a double membrane gas storage, so that the digestate still escaping amounts of residual gas are additionally collected. The fermentation residue camp 10 downstream phase separation station 11 is used to recover a high-solids fraction from the digestate, this fraction being used directly as a nutrient-rich organic NPKS fertilizer in the fertilizer storage 13 is supplied. The biofiltration obtained in parallel as a low-solids fraction enters the biofiltrate storage tank 12 , which also serves to decouple the process stages phase separation and Hemmstofentfrachtung. From the biofiltrate storage tank 12 For example, the biofiltrate may optionally be used as an organic NPKS liquid fertilizer for agricultural use or as a liquid component to produce a suitable biosuspension in the suspending station 6 be removed. In addition, there is the possibility of using biofilms in the suspending station 6 depleted of nitrogen and sulfur compounds, if necessary to avoid accumulation of toxic concentrations of ammonium and / or hydrogen sulphide in the fermentation substrate. In this case, this gets to the biofiltrate storage tank 12 removed biofiltrate only after passing through the inhibitor debris station 5 back to the biotechnology treatment process. Alternatively, the biofilter stock tank 12 a flotation station as part of the biofiltrate treatment fed to Vorflutqualität. Finally, the biofiltrate storage tank serves 12 Also as a reservoir for the Biofiltratpumpenstation. The fermenters 8th . 9 escaping biogases reach the autogenous pressure of the gases in the fermenters via pressure reducing valves in the crude gas line, which is operated at an absolute pressure of about 1050 mbar. In this crude gas line also passes in the Hydrolysestation 7 resulting hydrolysis gas, in addition to the there for stimulation The ambient air supplied to the aerobic hydrolysis process also contains the gases from the aerobic treatment of the biosuspension used and vapors of the resulting short-chain fatty acids.

Alternatively, from the biofiltrate, there is an estrogen tank 12 a flotation station as part of the biofiltrate treatment fed to Vorflutqualität. Finally, the biofiltrate storage tank serves 12 Also as a reservoir for the Biofiltratpumpenstation. The fermenters 8th . 9 escaping biogases reach the autogenous pressure of the gases in the fermenters via pressure reducing valves in the crude gas line, which is operated at an absolute pressure of about 1050 mbar. In this crude gas line also passes in the Hydrolysestation 7 Hydrogenysis gas which, in addition to the ambient air supplied there to stimulate the aerobic hydrolysis process, also contains the gases from the aerobic treatment of the biosuspension used and vapors of the resulting short-chain fatty acids. This so-called hydrolysis gas is sucked off by the hydrolysis reactor and compressed to an absolute pressure of at least 1050 mbar before being introduced into the crude gas line. This procedure allows the fermenters 8th . 9 to use the main and secondary fermenter stations as steel sheet structures made of non-conserved structural steel. The oxygen-containing mixed gas in the crude gas line first flows through the designed as Rieselkörperapparat gas desulfurization 14 , which has a pressure loss in the amount of about 40 mbar during normal operation. From the gas desulphurisation station, the biogas finally reaches the gas desulphurisation station 14 downstream double membrane gas storage 16 , which is operated with an absolute support pressure of the weather protection membrane in the amount of 1,008 mbar. If required, the desulphurised gas is supplied to the gas storage tank at a pressure of 1,008 mbar 16 taken out, compacted after passing through a gas drying station and an energetic gas utilization complex 17 , In the embodiment of a combined heat and power plant fed. The nutrient solution used in the gas desulphurisation station for the sulfur bacteria settling on the trickle bodies is pumped back continuously as bottom product to the head of the trickle body apparatus and undergoes a steady lowering of the pH value to values of less than pH = 2.0 when passing through the trickle body pack. Portions of the nutrient solution are taken batchwise from the apparatus sump when the pH has reached a size between 1.5 and 2.0. The withdrawn charge passes as a bio-acid in the Biosäurevorratstank 15 and stands there for the Wrasenwäscher the Hemmstoffentfrachtungsstation 5 as a washing liquid available. Additional stores of bio-acid are added to the hydrolyzation station 7 to promote the acidification of the biosuspension used there.

In the exemplary embodiment, pulp biogas with an energy content of 665 kWh used per t used is obtained from the biosuspension produced.

Example 2:

According to the 2 and 4 There is an arrangement for the material and energetic utilization of biogenic residues of a potato processing plant 2 for the production of high-energy biogas with a heating capacity of 9 MW _th . from an upstream bioethanol plant, with the help of which from the peelings and the sediments of the so-called white waters a Bioethanolmenge of at least 80,000 m ³ / a is obtained. The decision to use bioethanol in advance from the available starch-containing residues was made in the light of the assessment of the current market prices for the different forms of utility energy: Pos. Form of utility energy market price Useful energy content kWh / ME spec. Energy value € / MWh 1. Animal feed (feed barley) 140 € / t 4000 40, - Second Heat energy (WE) (natural gas) 0,70 € / m ³ 11 kWh / m ³ 63, - Third Cooling Energy (KE) (Absorption Cold) Heat energy + 10% 12.1 kWh / m ³ 69, - 4th Combined heat and power by means of CHP (diesel fuel) 1,30 € / 1 5 kWh WE / 1 + 4 kWh EE 144, - 5th Electric energy (EE) on average 0.15 € / kWh Direct application 1 150, - 6th Motor fuel energy on average 1.35 € / 1 at 45% efficiency 5.4 kWh / 1 250, -

For energetic, ecological and economic reasons, a variant with the highest proportion of high-quality energy form according to the above table is chosen in this example. The variants also prove to be the variant with the highest economic yield.

• – Rohstofflager,
• – Zerkleinerungsstation,
• – Station zur Herstellung einer Rohmaische,
• – Lager für die Zwischenstapelung der Schlempen und Weißwässer,
• – Umschlagseinrichtungen für den Vertrieb oder für die Entsorgung der Schlempen und Weißwässer.

In der Brennerei werden aus den anfallenden stärkehaltigen Reststoffen der Maniokverarbeitung insgesamt etwa 80.000 m³ Bioethanol gewonnen. Die anfallenden Schlempen werden anschließend als Teil der Anordnung für die stoffliche und energetische Reststoffverwertung der Kartoffelverarbeitungsstätte in eine Dickphase und in eine Dünnphase getrennt. Im Beispiel werden dabei aus
1 Masseteil Dickschlempe 14,7% Trockenmasseanteil und 88% organischem Anteil an der Trockenmasse,
0,0185 Masseteilen Schlamm aus der betrieblichen Abwasserbehandlung mit 28% Trockenmasseanteil und 65% organischem Anteil an der Trockenmasse und
0,283 Masseteilen eingedickter Schlamm aus der Flotation der anfallenden Biofiltrate mit 10,1% Trockenmassenanteil und 96% organischem Anteil an der Trockenmasse insgesamt unter Einsatz von recyceltem Biofiltrat
1,3 Masseteile Biosuspension mit 13,9% Trockenmasseanteil und 88,5% organischem Anteil an der Trockenmasse gewonnen. Die bei der Phasentrennung der in der vorgeschalteten Ethanolbrennerei anfallenden Ethanolschlempen gewonnene Dünnphase gelangt in die nachgeordnete Aufbereitungsanlage für die überschüssigen Biofiltrate aus den Gärresten der Methanfermentationsanlage. Aus der betrieblichen Abwasserbehandlumgsanlage 4 werden täglich ohne Zwischenpufferung Abwasserschlamm mit einem Trockensubstanzgehalt von ca. 28% im Umfang von 4,1 t mittels Schneckenförderer zur Suspendierstation 6 gefördert. Von der täglich anfallenden Dickschlempe werden der Suspendierstation 6 etwa 225 t Presskuchen aus der Phasentrennung der anfallenden Dickschlempe mit einem Trockensubstanzgehalt von 14,7% zugeführt.From a manioc processing plant for the production of chips and French fries, about 100,000 t peeling masses are produced annually. From the production wastewater after the purification of the input materials, the so-called starchy white waters are obtained. Both streams are used as feedstocks for an ethanol production plant, which do not contain the following plant components compared to conventional distillers:

• - raw material storage,
• - Crushing station,
• - Station for making a Rohmic,
• - warehouses for intermediate storage of vats and white waters,
• - Transfer facilities for the distribution or disposal of vinasse and white water.

In the distillery, a total of about 80,000 m ^{3 of} bioethanol is obtained from the resulting starch-containing residues of manioc processing. The resulting vats are then separated into a thick phase and a thin phase as part of the arrangement for the material and energy recovery of the potato processing plant. In the example will be off
1 part of solid sludge 14.7% dry matter content and 88% organic content of the dry matter,
0.0185 parts by weight sludge from the operational wastewater treatment with 28% dry matter content and 65% organic content of the dry matter and
0.283 parts by weight of thickened sludge from the flotation of the resulting biofiltrate with 10.1% dry matter content and 96% organic content of the total dry matter using recycled biofiltrate
1.3 parts by mass of biosuspension with 13.9% dry matter content and 88.5% organic content of the dry matter. The thin phase obtained in the phase separation of the ethanol sludge obtained in the preceding ethanol distillery passes into the downstream processing plant for the excess biofiltration rate from the fermentation residues of the methane fermentation plant. From the operational Abwasserbehandlumgsanlage 4 Every day without intermediate buffering, sewage sludge with a dry matter content of approx. 28% in the amount of 4.1 tonnes by means of screw conveyors to the suspending station 6 promoted. From the daily arising Dickschlempe become the Suspendierstation 6 About 225 t press cake from the phase separation of the resulting Dickschlempe fed with a dry matter content of 14.7%.

Additionally arrive in the suspension station 6 daily 63.5 t of thickened flotate sludge with a dry matter content of 10.1% from the removal of suspended solids of the excess biofiltrate quantities by means of pressure-release flotation. This will be in the suspension station 6 a total biosuspension amount of 292.5 t / d was produced with an average dry matter content of 13.9%. The suspension station 6 consists of a stirred tank made of reinforced concrete with a useful volume of 600 m ³ , taken daily up to 300 m ^{3 of} biosuspension and the Hydrolysestation 7 be supplied. The hydrolysis station 7 consists of a ventable stainless steel agitator, depending on the gas attack in the fermentation 8th . 9 selectable amounts of ambient air are supplied. The net volume of the hydrolysis station 7 is 800 m ³ . The hydrolysis station 7 Hydrolyzate quantities of up to 280 m ^{3 are} taken daily in several dosage units and alternately two main fermenters operated in parallel 8th supplied to the main fermenter station. For the main fermenters 8th They are partially and hydraulically mixed devices with usable volumes of 8,000 m ³ each, which are made of unpreserved sheet steel. In the main fermenters 8th became a mesophilic seed culture prior to start-up 1 submitted from an existing fermentation plant for the material and energy recovery of predominantly lignocellulosic starting materials. When dosing hydrolyzate from the hydrolysis station 7 into the two main fermenters 8th each fermentation substrate amounts from the main fermenter 8th discharged. These fermentation substrate quantities go directly into the secondary fermenter 9 the post fermenter station. The secondary fermenter 9 is like the main fermenter 8th constructed, also has a useful volume of 8,000 m ³ and has in the container wall integrated heating surfaces, with which in the secondary fermenter 9 Media temperatures between 52 and 57 ° C can be maintained. Every time the secondary fermenter is loaded 9 becomes fermentation residue from the secondary fermenter 9 in the digestate warehouse 10 discharged. The digestate warehouse 10 is an unheated open stirrer made of sheet steel with a useful volume of 6,000 m ³ . This is with a gas storage 16 covered, which has a maximum storage capacity of 6,000 m ³ . This is while maintaining a middle level of the gas storage 16 ensures such a process decoupling, the disturbances in the downstream gas treatment and in the energetic gas utilization complex 17 bridged by up to 2 hours.

The safety device in the form of the flare system with a thermal output of 9 MW does not yet have to be used. The digestate warehouse 10 serves both the residual degassing of the fermenters 8th . 9 fermentation residues discharged from the main and secondary fermenter stations as well as the decoupling of fermentation station and digestate treatment. To obtain a nutrient-rich fertilizer fraction, digestate is the digestate storage 10 taken and a phase separation station 11 fed. There by means of press screw separators and decanters, the separation of the fermentation residues in press cake with dry matter contents of on average 30% and biofiltrate. During the press cake as a high quality fertilizer in the fertilizer storage 13 is entered with a bulk material capacity of 2,000 m ³ for about 20-day intermediate stacking, the resulting biofiltrate enters the closed biofiltrate storage tank 12 made of reinforced concrete with a useful volume of 1,000 m ³ . The biofiltrate quantities not required for re-use in the fermentation process are processed into flooded wastewater with the aid of a process network of flotation, UASB fermentation, nitrification and denitrification. The thin sludge from the phase separation of the sludge produced in the upstream ethanol distillery is fed to the downstream process before the UASB fermenter station. That in the hydrolysis station 7 accumulating gas / acid vapor mixture is compressed to about 50 mbar pressure and fed to the crude gas line. From the fermenters 8th . 9 the main and Nachfermenterstation passes the resulting gas by means of autogenous pressure also in the crude gas line. Between the crude gas line and the gas storage 16 is the gas desulphurisation station 14 arranged for a raw gas flow of about 1100 m ³ / h. The spent bottom product of the designed as Rieselkörperapparat gas desulfurization station 14 is discharged as bio-acid and in the bio acid storage tank 15 cached with a useful volume of 100 m ³ . The Biosäure serves primarily to supply the Hemmstoffentfrachtungsstation 5 with fluid for the Wrasenwäscher and beyond to support the hydrolytic treatment of the biosuspension in the Hydrolysestation 7 , The plant characterized in the example for the utilization of biogenic residues of a manioc processing plant thus serves to produce 80,000 m ^{3 of} bioethanol, which is preferably used as a motor fuel, and to produce 8.9 million m ^{3 of} biogas with a mean methane content of 65%.

This amount of methane corresponds to about 108 m ^{3 of} biogas per t used Dickschlempe. From the amount of biogas produced, 28,600 MWh of electrical energy and 33,600 MWh of thermal energy are generated annually by means of combined heat and power plant technology.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 3627253 C2 [0004]
• DE 4000834 C2 [0006]
• DE 4226087 A1 [0008]
• DE 19613397 C2 [0010]
• DE 19615551 C2 [0011]
• DE 102004030482 B4 [0014]
• DE 102007004135 A1 [0017]
• DE 202008014330 U1 [0018]
• DE 102008060140 A1 [0020]
• DE 102010005818 A1 [0022]

Cited non-patent literature

• Brewery Forum, Issue 9/2000, entitled "Grain Fermenting to Biogas" [0015]

Claims (15)

Process for the material and energy recovery of biogenic residues from potato processing plants by using the residues in a wet fermentation, by concentrating the total nutrient potential in the form of nitrogen, phosphorus, potassium and sulfur in a fertilizer fraction obtained from the fermentation residues, and by providing the desulfurized biogas for the energetic utilization, characterized in that are used as wet fermentation Hefefermentation for bioethanol production and / or methane fermentation for biogas production, that the resulting biogenic residues from the processing of starchy root crops, such as potatoes, sweet potatoes, cassava, tapioca, cassava, in the form of Peelings, starchy white waters, residues from the purification of feedstocks, sludge from the upstream ethanol distillation, aqueous media from the periodic plant cleaning and / or Sch lambing, that the available residues are subjected to a suspending process that is set using additives with dry matter contents of at least 25% in the biosuspension, a dry matter content between 12 and 18%, that the biosuspension produced is subjected to an aerobic hydrolysis process that the biosuspension hydrolyzate produced an anaerobic fermenter system from at least one hydraulically and partially mixed fermenter with initially used and constantly reproducing special culture is supplied that contained in the recovered feedstock potential of plant nutrients as a mixture of the solid phase of the fermentation residues and from the Hemmstoffentfrachtung the Biofiltrate resulting liquid washing media is obtained with high levels of ammonium and sulfur compounds and that the desulfurized, dried and compressed biogas for the coupled production of electrical shear and thermal process energy is used. Method according to claim 1, characterized in that at least portions of the sour mashes produced in the yeast fermentation are added to the biosuspension in the form of solids-rich presscakes. Method according to one of claims 1 and 2, characterized in that from the production effluents of the starch production site before or after an aerobic and / or anaerobic treatment, a sludge fraction is obtained as additional biogenic waste fraction. Method according to one of claims 1 and 3, characterized in that are preferably used as additives grain chaff, mill dust and / or brush dusts from the grain cleaning in the suspending process. Method according to one of claims 1 to 4, characterized in that are used as process water biofiltrates from the mechanical phase separation of the resulting fermentation residues in the suspending process. A method according to claim 5, characterized in that the biofilms prior to use in the suspending process to avoid inhibiting the fermentation process concentrations of toxic ingredients ammonium and / or hydrogen sulfide are removed. Method according to one of claims 5 and 6, characterized in that the biofiltrate parts of the dissolved ammonium and / or dissolved hydrogen sulfide in an expeller at up to 65 ° C elevated temperatures and at an absolute pressure in the supernatant fumes of at most 980 mbar withdrawn be that the ammonia and / or hydrogen sulfide-containing vapors of the expeller are cooled in an intermediate heat exchanger to temperatures of 45 ° C maximum, that the cooled fumes containing ammonia and / or hydrogen sulfide are fed to a downstream Wrasenwäscher in the form of a trickle body apparatus, being used as a washing medium sulfuric biosäure from the biogas desulphurisation with a temperature of maximally 25 ° C and a pH value between 1 and 3,5 is used and that the scrubber sump when reaching the upper pH limit value between 10 and 60 mass% as fertilizer concentrate with high nitrogen and / or sulfur concentration deprived of them and replaced by fresh sulfurous bio-acid. Method according to one of claims 1 to 7, characterized in that the hydrolysis is carried out under intensive mixing with ambient air in a stirred tank at temperatures between 50 and 60 ° C that the hydrolysis ambient air in an order of between 2 and 10 vol .-% of biogas obtained in the entire fermentation process is added so that an average residence time of the biosuspension in the hydrolysis of about 2 days is maintained and that the hydrolysis between 20 and 100% of biosulfurization incurred in the biological desulfurization of bio-acid is added. Method according to one of claims 1 to 8, characterized in that the resulting hydrolysis gas is compressed to at least 30 mbar and introduced into the central crude gas before the gas desulphurisation station or that the resulting hydrolysis gas is compressed to at least 30 mbar and introduced into the corrosion-resistant secondary fermenter station. Method according to one of claims 1 to 8, characterized in that the special culture used for the fermentation process as a starting culture and is obtained with the addition of predominantly lignocellulosic starting materials in a breeding station for mesophilic or thermophilic mixed cultures. Arrangement for carrying out the method according to claim 1, consisting of at least one suspending station ( 6 ), a fermentation station for methane fermentation ( 8th . 9 ), a phase separation station ( 11 ) for the digestate, a biofiltration stock tank ( 12 ), a gas desulphurisation station ( 14 ), characterized in that the suspending station ( 6 ) is associated with a storage and dosing system for dry substance-rich additives, that between the biofilter stock tank ( 12 ) and the suspending station ( 6 ) an inhibitor decontamination station ( 5 ) is arranged as a gas desulphurisation station ( 14 ) a gas scrubber is preferably arranged in the form of a trickle apparatus that for the storage of the gas in the desulphurisation station ( 14 ) obtained sulfurous bioacid between the gas desulphurisation station ( 14 ) and the inhibitor decontamination station ( 5 ) and / or the hydrolysis station ( 7 ) a Biosäurevorststank ( 15 ) is arranged that between the suspending station ( 6 ) and the fermenter station ( 8th . 9 ) a hydrolysis station ( 7 ) and that the fermenter station ( 8th . 9 ) from at least one main fermenter ( 8th ) and at least one downstream secondary fermenter ( 9 ) consists. Arrangement according to claim 11, characterized in that the plant components are preceded by a plant for the production of bioethanol from the inventory of carbohydrates contained in the peeling masses and / or the starchy sediments of the white waters. Arrangement according to claim 11, characterized in that at least the main fermenter (s) ( 8th ) are hydraulically mixed, but not completely mixed, apparatus. Arrangement according to one of claims 11 and 12, characterized in that the secondary fermenter ( 9 ) are designed as batchwise operated and heated stirred tank. Arrangement according to claim 11, characterized in that in the main fermenters ( 8th ) and in the downstream secondary fermenters ( 9 ) different methane bacteria mixed cultures are used,

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