RU2595143C1 - Reactor for aerobic fermentation of biomass - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: cylindrical temperature-controlled reactor housing is installed vertically and comprises a loading device pipe connected via bearing assemblies with an annular hollow pipe of a mixer, to the output of which there is connected a comb with holes. Mixer pipe rotation around the pipe of the loading device is ensured by a reversible electric drive via a reduction gear, connected with the ring gear on the mixer pipe. Preliminary heating of biomass is performed due to ascending gases in the feeding pipe, and the beginning of the phase of exponential growth of the biomass is carried out in the zone of the comb during intense mixing of raw materials and its saturation with oxygen. Also, inside the body on an insulated plate, there are arranged angle electrodes connected in pairs by a power supply source; inside, they contain a brush bio-loading promoting electric retention and generation of bacteria. For temperature control and selection of excess thermal energy a heat exchanger body is used, connected through a circulation pump with a heat accumulator, connected to a low-potential circuit comprising a steam turbine, a condenser and the second circulation pump.

EFFECT: invention makes it possible to perform accelerated aerobic solid-phase fermentation of biomass.

1 cl, 1 dwg

Description

The invention relates to agriculture and forestry, in particular to the processing of livestock and other biowaste, as well as to the processing of organic raw materials contained mainly in municipal solid waste.

Known devices, methods and systems for this purpose, intended for aerobic digestion, for example, “Method for processing manure into fertilizer”, authors Glazkova IK, Kovaleva NG, Tumanova IG according to the patent of the Russian Federation No. 1813085 [1].

The essence of this method consists in layering manure and moisture-absorbing organic material, mixing these components at the compost site and subsequent aerobic fermentation in the fermenter with periodic ventilation, and before composting, the mixture of components is covered with a layer of ready-made compost.

The disadvantage of this method and devices that implement this method is the long composting even under favorable external conditions (more than 7 days) and the low productivity of the fermenter, including due to the return to start a new portion of the mixture of components - previously prepared organic fertilizer (according to description of an example patent, its layer should be 10 cm).

Also known is "Installation for the processing of organic waste into fertilizer" by the authors Yegina N.L. and Mircetich S.M. according to the author's certificate of the USSR No. 1706423, IPC A01C 3/00 [2].

This device contains a conveyor belt with electric drive, hoppers for manure, peat and litter, a container for biological product, a device for heating waste, devices for draining and moistening waste, pipelines with electric pumps, humidity sensors and filters.

The disadvantage of this device is the great difficulty in implementation due to the bulkiness of the design and difficulties with the processing technology, which boils down to controlling the moisture content of the raw materials.

In addition, each time a new portion of the material is loaded, it is necessary to heat it through electrodes lowered into the feed from an external power source, which consumes considerable energy.

The well-known "Method of preparing compost for multi-purpose" authors Kovaleva NG, Malinina B.M. and Tumanova I.P. according to the patent of the Russian Federation No. 2112764, IPC C05F 3/00 and an example of its implementation set forth in the description of the patent [3].

According to this patent, layering of manure and moisture-absorbing material is performed, mixed, placed in a fermenter and aerobic composting is carried out for 3 ... 4 days when aerated with oxygen-containing gas.

The disadvantage of this method is its low productivity, due to the lack of a continuous fermentation process of newly incoming raw materials. In addition, the fermenter in this case is a tunnel trench, which limits the year-round use of this method.

The well-known "Installation for the preparation of composts" authors Rabinovich P.M., Kovaleva NG and others according to the certificate for utility model No. 39599, IPC C05F 3/00 [4]. This installation and compost preparation options are also described in the doctoral dissertation of Rabinovich P.M. [5].

This installation contains a cascade of containers for the fermented mixture with a lid, gates and sockets for installing a thermometer, an oxygen meter, and a blower with a system of pressure ducts installed in the bottom of the container, and the cascade of containers is mounted in one housing.

In this device, fermentation is also carried out not continuously, but occasionally in each individual tank from the moment of its loading to the end of the process. To preheat the mass loaded into the tank, it is necessary to expend thermal energy (supply hot water, hot air or pass electric current through special electrodes), and the thermal energy of the biomass heated later to 70 ° C is not used and its temperature (overheating - mass burnout) is not controlled . In addition, it is not possible to use this device in winter conditions.

The closest technical solution (prototype), which implements continuous solid-phase fermentation of organic raw materials, is the “Biothermal drum” according to the USSR copyright certificate No. 363523 of the authors M. Myagkova, GM Alekseeva et al., IPC B02C 17/18 [6].

A biothermal drum for processing household garbage contains a cylindrical body, loading and unloading devices, exhaust pipes, a compressor for supplying air into the inside of the housing and screw blades for moving raw materials with a horizontal (with a small angle of inclination towards the exit) position of the housing.

With forced heating and slow rotation of the bio-drum for several days, metal, plastic and wood are separated from bio-raw materials. At the outlet of the casing, these products are screened by separation, and partially fermented organic types of raw materials are sent for further fermentation to special tunnels or holding pools for up to 30 ... 40 days.

The share of bio-raw materials in the drum is from 5 to 12%, and during being in the casing it does not even manage to go through the first stage of lag phase fermentation.

KM-101L type bio-drums are huge structures (4 meters in diameter and 30 or 60 meters long), which require large amounts of energy to rotate and heat up the entire mass of household waste [7]. In addition, the operation of this device is also subject to seasonal restrictions, so the fermentation processes in the bio-drum are not continuous.

The objective of the present invention is to remedy these disadvantages.

The technical result of the proposed solution is as follows:

- increasing the efficiency of the reactor and accelerating aerobic fermentation by feeding the next portion of bio-raw materials to the reactor zone, in which the phase of exponential growth of the microbial culture occurs while stirring and aerating a certain amount of mass in this zone;

- increasing the efficiency of aerobic fermentation due to the cultivation and electro-retention of a community of microorganisms inside the housing and their recirculation into the fermented biomass by installing angular perforated electrodes connected to a power source in the zone of the exponential growth of bacteria, and a ruff bio-loading is placed inside the electrodes;

- increasing the efficiency of the aerobic fermentation process by controlling the temperature of fermentation and the selection of excess heat energy, leading to the burning of raw materials, by placing heat exchangers in the lower zone of the exponential growth of bacteria, connected to a heat accumulator that further transfers thermal energy through a low-temperature working fluid (for example, freon) to a steam turbine connected to an electric generator, which also allows the generation of electrical energy (ORC system);

- acceleration of the aerobic process due to the transmission of hot oxygen-containing gas from the zone of exponential growth of bacteria into the loading device for heating the newly incoming biomass;

- reducing the cost of electricity required to preheat the newly arrived biomass and to move it along the body by placing the cylindrical body vertically and using gravity to move the raw materials.

As a result of a search by sources of patent and scientific and technical information, we did not find a set of features characterizing the described “Reactor for Accelerated Aerobic Solid Phase Fermentation”. Thus, the proposed technical solution meets the criterion of "new".

Based on a comparative analysis of the proposed solution with the prior art, it can be argued that between the set of distinctive features, the functions performed by them and the task to be achieved, the proposed technical solution does not follow explicitly from the prior art and, in our opinion, meets the eligibility criterion of “inventive step”.

The proposed technical solution can be widely used as a universal reactor for accelerated processing of various types of organics into fertilizer.

The drawing in section shows the design of the "Reactor for aerobic fermentation of biomass".

The reactor comprises a thermostatically controlled cylindrical body 1, mounted vertically, with a pipe 2 of a biomass loading device buried inside the body, a cover 3 with an outlet pipe 4, a press extruder 5 for preparing raw materials, a reversible electric drive 6, which controls a gear 7 connected to the body and the annular hollow tube 9 of the mixer with its comb 10, having inclined rods with openings for the exit of oxygen-containing gas, which rotates by means of a pinion gear 8 and which comes from the compressor 11 through the valve 12 It is connected to a sleeve 13 connected to the body and sliding on the pipe surface, and through the valve 14, gas enters the body pallet having a perforated cover 15.

The power source 16 through the wires placed in the insulating plate 17, is connected to the electrodes of perforated metal corners 18 attached to the plate, the corners are located with their edges facing upward towards the moving biomass, and between the edges of the corners there is a ruff bio-loading 19.

The first circulation pump 20 is connected between the housing heat exchanger 21 and the heat accumulator 22, from the output of which the low-temperature working fluid enters the steam turbine 23 connected to the electric generator 24, and then from the turbine exit through the condenser 25 and the second circulation pump 26 to the heat accumulator heat exchanger, closing low-potential contour of the working fluid. The finished product is dispensed through the unloading device 27. Pressure, temperature, gas analyzers and automation circuitry are not shown in the drawing.

The reactor for aerobic solid-phase fermentation of biomass works as follows.

Raw materials with adjustable humidity is fed into the housing 1 through a press extruder 5, a cover 3 and a pipe 2 of the loading device. In the process of constant operation, the entire internal volume of the housing is completely filled with raw materials, and the newly supplied still cold portion of biomass remains in the upper part of the wide pipe with a diameter of 0.2 ... 0.4 of the dimensions of the cylindrical body.

The reversible electric drive 6 through the gear 7 mounted on the housing, and the ring gear 8, belonging to the annular hollow mixer 9, carries out its rotation. At the same time, oxygen-containing gas enters from the compressor 11 through the valve 12 and the slip clutch 13 connected to the housing into the holes inside the annular hollow tube of the mixer and enters the biomass through the holes of the mixer 10 of the mixer. Through the valve 14, gas can also be supplied to the housing pan, from where it enters the biomass through the perforated tray 15. The hot exhaust gas together with carbon dioxide rises, heats the raw materials in the pipe 2 and exits through the exhaust pipe 4 (the movement of gases in the housing is shown by dashed lines , and the promotion of raw materials - in solid lines). The rods (“teeth)” of the comb have deviations from the vertical axis — they are bent at a small angle (10 ... 15 °), which, when it is reversed in a circular motion, facilitates the movement of biomass in the comb zone in the vertical plane and the full filling of the body cavities that serve, including drives of colonies of microorganisms, for their further inoculation into newly entering biomass.

It is known that the microbiological composting process is described by the growth curve of the microbial culture, which consists of four phases: the lag phase, the exponential growth phase, the stationary phase, and the cell lysis (death) phase [8].

The lag phase is a long process of self-heating of biomass. In the proposed device, this period is significantly reduced due to its preliminary heating in the pipe 2, the lower end of which is at the beginning of the zone of the phase of exponential growth of bacteria. A new portion of the raw material coming from the pipe again under the action of gravity is mixed with a comb 10 of the mixer and at the same time it is actively saturated with oxygen-containing gas coming from the ends of the mixer from the compressor 11 through the open valve 12, the slip clutch 13 and the annular hollow tube 9 of the mixer.

The phase of exponential growth of microbes that began in the zone of location of the comb 10 of the mixer continues when the biomass moves down to the zones of location in the casing of the electrodes 18 and heat exchangers 21.

Perforated metal electrodes 18 are mounted on an insulated plate 17 (or several plates) with the corners pointing upward towards the movement of raw materials, which prevents the ruffled bio-loading tapes [9] placed in them for destruction and enhanced reproduction of colonies of microorganisms in them.

In addition, an electric potential for electrically holding bacteria [10, 11] has been applied to pairwise connected electrodes 18 from a power source 16, which facilitates the transfer of microorganisms into the electrode zone and their penetration through perforation of the side walls of the electrodes to ruff biofeedback. Oxygen-containing gas also enters this zone through valve 14 and housing pan 15.

In the process of solid phase fermentation, biomass is heated to 70 ° C or more, which leads to the burning of raw materials. In order to regulate the temperature in this zone of the housing, a heat exchanger 21 is introduced, connected through the first circulation pump 20 to the heat accumulator 22, the heat is taken from which is closed loop with a low-potential working fluid.

The working fluid, evaporating in the heat exchanger heat exchanger, enters the steam turbine 23, which rotates the electric generator 24. After the turbine, the working fluid in the condenser 25 turns into liquid and returns to the heat storage heat exchanger 22 by the second circulation pump 26. The excess of the received electricity from the generator 24 enters the consumers network .

Below the zone of location of the heat exchangers 22 of the body begins the stationary phase of the life of bacterial cells, passing into the phase of lysis of bacteria.

The total height of these zones and the degree of readiness (complete conversion of bio-raw materials into compost) depends on the design and manufacturing technology of the housing 1.

By prior arrangement with representatives of Avangard OJSC, for the described “Biomass Aerobic Fermentation Reactor” it is proposed to use insulated containers made of composite materials with a diameter of up to 4 meters, a section length of 6 and more meters [12].

With a tower arrangement of the building, loading it with bio-raw materials will present a certain problem, therefore, it is advisable to place such a structure, if possible, for example, in a hillside or buried in the ground. With a sufficient height of the cylindrical body 1, the finished product will be discharged by a screw pump through the unloading device 27.

In another embodiment, when the height of the casing is insufficient for the complete fermentation of bio-raw materials, the incomplete product with a temperature of about 30 ° C is discharged by a screw pump with a heat-insulated casing into the heat-insulated containers of Avangard OJSC, which are in a horizontal position, to complete the lysis stage and completely transform the product into valuable compost.

The proposed reactor allows to accelerate the processes of aerobic solid-phase fermentation, which makes it possible to increase the volume of processed manure, manure and other organic raw materials.

INFORMATION SOURCES

1. Glazkov I.K., Kovalev N.G., Tumanov I.P. A method of processing manure into fertilizer. RF patent No. 1813085, MK C05F 3/00, C05F 15/00 (analogue).

2. Egin N.L., Mircetich S.M. Plant for processing organic waste into fertilizer. USSR author's certificate No. 1706423, IPC A01c 3/00 (analogue).

3. Kovalev N.G., Malinin B.M., Tumanov I.P. A method of preparing compost for multipurpose use. RF patent No. 2112764, IPC C05F 3/00 (analogue).

4. Rabinovich P.M., Kovalev N.G. Installation for composting. Utility model No. 39599, IPC C05F 3/00 (analogue).

5. Rabinovich P.M. Improving aerobic solid-phase fermentation of organic raw materials by optimizing the technological parameters of the production process. Doctoral dissertation. St. Petersburg-Pavlovsk, 2006.

6. Myagkov M.I., Alekseev G.M. and other Description of the invention to the copyright certificate of the USSR No. 363523, IPC B02c 17/18 (prototype).

7. Aerobic fermentation in the processing of solid waste [Electronic resource]. Access mode: http://ztbo.ru. Section: garbage processing.

8. Artamonov B.C., Ivanyuk G.K., Zhurkovich V.V. and others. Resource-saving technologies for the processing of municipal solid waste from housing and communal services, ensuring the safety of the megalopolis. St. Petersburg: Humanism, 2008.

9. Ecopromecology. Ruff biofuel [Electronic resource]. Access mode: www.epcs.ru/03.

10. Gvozdyak P.I., Chekhovskaya T.P. Electro-retention of microorganisms // Microbiology, vol. XLV, 1976, no. 5, p. 901-904.

11. Chekhovskaya T.P. Electro-retention of microorganisms in water treatment. The dissertation of a doctor of biological sciences. Kiev, 1983.

12. Oversized fiberglass products. Plastic and rubber products of Avangard OJSC [Electronic resource]. Access mode: http://www.avangard-plastik.ru.

Claims (1)

 A reactor for aerobic fermentation of biomass containing a cylindrical thermostatic housing, loading and unloading devices, an exhaust pipe, an electric drive with a gearbox and a compressor for aeration of biomass in the housing, characterized in that a loading device pipe is inserted into the vertically mounted housing, connected through the bearing units to the annular hollow a mixer pipe, at the outlet of which a comb is connected with openings for the exit of oxygen-containing gas, to the annular hollow pipe with the possibility of a coupling connected through a valve to a compressor, the latter through another valve also connected to a housing pan equipped with a perforated cover, the electric drive being reversible and connected to the ring gear on the annular hollow pipe, below the comb in the housing on the insulating the plate contains perforated corner electrodes with a brushed bio-loading placed in them, connected to a power source, while the housing contains a heat exchanger, with connected outside the casing through the first circulation pump with a heat accumulator, the heat exchanger of which with a low-temperature working fluid is connected to the turbine outlet, its output through a low-potential circuit condenser and the second circulation pump is connected to the heat accumulator heat exchanger, and the loading device pipe is made with a diameter of 0.2 ... 0.4 from the dimensions of the cylindrical body for the preliminary accumulation of new portions of the incoming biomass and the passage of spent hot gas through it, the boot cover It is equipped with an outlet pipe for hot gases, and the comb rods at the mixer are made with a deviation from the vertical axis of 10 ... 15 ° to improve mixing of biomass.

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