RU2528262C2 - Method of processing poultry farm litter and device for its implementation - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: invention can be used in preparation of enhanced fuel from wastes of poultry farms. The method of processing poultry farm litter comprises granulating the wet raw material in the granulator. The granules obtained are dried in a drying chamber at a temperature of 150°C and heated in the pyrolysis chamber without access of air at a temperature of 550°C in the presence of gaseous coolant with the transfer of the pyrolysis products to the solid product and steam-gases with their subsequent partial condensation into the liquid fuel.

EFFECT: inventions enable to increase the yield of liquid fuel from organic material to 31,6% with a decrease of water content in it to 5%, to increase the calorific value by 15-20%, and to reduce energy consumption per 1 kg of the obtained solid and liquid fuel, to obtain the solid carbon-mineral product with a yield of up to 15%, which can be used as fuel and as fertiliser.

8 cl, 7 dwg, 5 tbl, 1 ex

Description

FIELD OF THE INVENTION

The group of inventions relates to the field of processing litter of poultry farms in refined fuel, in particular to the technology of pyrolytic conversion of organic substances into solid and liquid fuel and a device for its implementation.

State of the art

A known method of thermal processing of wood (RF patent No. 2083633, 11.24.1995, СВВ 53/02). The method includes preliminary drying of wood and subsequent heat treatment in the presence of a gaseous coolant in a continuous process with successive passage through zones of drying, pyrolysis with the formation of charcoal, its calcination and cooling with countercurrent supply of a cooling agent, which uses flue gases from complete combustion of fuel containing oxygen in them is 1.5-7.0%, while these gases, after passing through the cooling zone, are used as a coolant in the calcination zones, pi Rolise and drying.

The methods described above are low productivity, require additional fuel and do not allow the processing of wood with a moisture content above 25%.

A known installation for pyrolysis of wood is a vertical continuously operating retort (Vyrodov V.A., Kislitsyn A.N. Technology of wood chemical production. M: Forest industry, 1987, p.216-218). It is a steel cylindrical chamber with internal heating, mounted vertically and containing distribution cones for entering the coolant and the selection of steam and gas, a device for loading wood and coal, a condensation system for processing steam and gas. The height chamber is conditionally divided into three zones: wood drying, pyrolysis and calcining of coal, coal cooling. Pyrolysis steam gas is processed in a condensation system to remove liquid pyrolysis products. The remaining non-condensable gases diluted with the coolant (flue gas) are fed in a mixture with additional fuel for combustion and formation of the coolant for pyrolysis in a special furnace device. The disadvantages of the installation are: the need to process combined-cycle gases, which complicates its operation, the need for additional fuel, the lack of the possibility of processing wood with a humidity above 25%.

A well-known installation for pyrolysis of wood is a retort of the company Lambibit (Vyrodov V.A., Kislitsyn A.N. Technology of chemical production. M: Forest industry, 1987, p.218-220). It is a cylindrical chamber mounted vertically, with the transition in the lower part into a cone. Conditionally, the height retort can be divided into 3 parts: the upper one, intended for drying wood, the middle (extended), where pyrolysis and calcination of coal takes place, the lower one - the coal cooling zone. In the interval between the upper and middle zones there is a furnace device, where hot pyrolysis steam gas, taken from the bottom of the middle part of the retort (pyrolysis zone), and also air for burning gas and vapor are supplied through special fittings using gas blowers. In the upper part, the installation is equipped with a device for loading wood, in the lower - a device for unloading coal. Thus, the retort “Lambibit” eliminates the need for a condensation system to trap liquid products. The heat from burning raw steam and gas is sufficient to ensure the thermal regime of drying and pyrolysis of wood with a moisture content of up to 35%, in which case additional fuel is not required.

The disadvantage of the retort "Lambit" is the location of the combustion device in the gap between the pyrolysis zone and the drying zone of wood. Partially burnt gas-vapor from the combustion device is fed to a retort on a wood layer heated only to 100 ° C, which excludes continued combustion and leads to the extinction of the torch. The temperature in the pyrolysis zone of the retort therefore does not exceed 500 ° C, which reduces the productivity of the installation, does not allow to obtain high-quality coal due to insufficient calcination, and excludes the possibility of processing wood with a humidity above 35%. The coolant leaving the drying zone contains unburned resin and other hardly combustible ingredients, which leads to irretrievable heat losses and the emission to the atmosphere of the working area. The distribution of gas flows in the retort "Lambibit" is not regulated.

A known method for the production of charcoal and a plant for the production of charcoal (RF patent No. 2166527, 02.01.2000, CB 53/02). The method includes preliminary drying of the raw material and subsequent heat treatment in the presence of a gaseous coolant in a continuous process with successive passage of the drying, pyrolysis zones with the formation of charcoal and its calcination. The use of a gas coolant in the pyrolysis zone dramatically reduces the concentration of wood-tar products in combined cycle thermal decomposition of raw materials, increases their temperature and complicates the condensation system for the separation of bio-oils.

There is a method of thermal processing of organo-containing raw materials into gaseous and liquid fuels (RF patent No. 2395559, 07.27.2010, СВВ 57/10), by heating first in a drying chamber, which is a hopper, with a drying agent at a temperature of 160-200 ° C, obtained by mixing flue gases passing through the jacket of the pyrolysis chamber, with air, and then without air in the pyrolysis chamber with the conversion of the pyrolysis products into coal and gaseous fuel - a gas-vapor mixture with subsequent condensation of part of the gas-vapor mixture into liquid fuel, and part ensirovannoy gas mixture after preheating to a temperature of 450-520 ° C is fed into the pyrolysis chamber in an amount providing a residence time in the pyrolysis chamber of the pyrolysis products of not more than 2 seconds, and the pressure in the pyrolysis chamber at 500-1000 Pa. The known method is adopted as a prototype.

The known method is not sufficiently effective in terms of obtaining the output of a useful product, because solid residue is burned, which also makes the method not environmentally friendly.

There is a method of processing wood biomass in the form of wood chips to produce biomasses and charcoal and a drying-retort module for its implementation (RF patent No. 2338770, СВВ 53/02, СВВ 1/04, 11/20/2008). The drying-retort module contains a vertically mounted housing separated by clamps on the drying chamber, a tree biomass pyrolysis chamber mounted on the upper and lower parts of the housing for loading and unloading coal, a combustion chamber, a bio-oil extraction unit, and a first gas circuit in the form of a gas duct with a gas blower for supplying gas and vapor from the pyrolysis chamber of wood biomass and calcining coal into a combustion chamber located in the zone of pyrolysis of wood biomass and calcining coal, the module is additionally equipped with a mixing chamber for forming a heat transfer fluid connected through a gas circuit to the combustion chamber, a second gas circuit in the form of a gas duct with a control flap for supplying flue gases from the combustion chamber to the lower part of the wood biomass drying zone, and a third gas circuit in the form of a gas duct with a control flap and a gas blower for recirculation flue gases from the upper part of the drying zone to its lower part for the reverse-counter-current-transverse process of preparation of raw materials with the aim of producing bio-oils and coal from wood biomass. A disadvantage of the known device is the insufficient yield of a useful product from processed raw materials.

Disclosure of invention

The objective of the present invention is to increase the yield of a useful product while maintaining the environmental safety of the method.

To solve this problem, a method for processing poultry bedding is proposed, in which the moisture-containing processed raw materials are dried, and then heated in a pyrolysis chamber without air access with the conversion of the pyrolysis products into a solid product and combined-cycle gases with their subsequent partial condensation into liquid fuel. The difference of the claimed method is that before drying the wet raw materials are granulated, the obtained granules are dried at a temperature of 150 ° C, and heating in the pyrolysis chamber is carried out at a temperature of 550 ° C in the presence of a gas coolant.

Pyrolysis is preferably carried out at atmospheric pressure.

Wet raw materials are preferably pre-granulated to a granule size of 5 to 6 mm in diameter and 20 to 35 mm in length.

In a preferred embodiment, the liquid fuel in the form of biomass is obtained from the pyrolysis steam-gas by fractional condensation.

In another preferred embodiment, the resin-free steam-gases obtained as a result of fractional condensation are fed for combustion to form a gas coolant for pyrolysis and drying of the processed raw materials.

The spent drying agent is preferably discharged into the atmosphere.

The calcined remainder of the granules is preferably cooled to a temperature of 150-200 ° C and selected in the form of a solid carbon-mineral product.

In another aspect of the invention, there is provided a device for processing a litter of a poultry farm, comprising a vertically mounted housing including a drying chamber and a pyrolysis chamber, a feed loading unit, a carbon-mineral product discharge unit, a combustion chamber, at least one liquid biofuel extraction unit, a mixing chamber for forming a heat transfer fluid connected through a first gas circuit with a combustion chamber, a first gas circuit made in the form of a gas duct with a gas blower, a second gas circuit and a third gas circuit a tour made in the form of a gas duct with a gas blower. In contrast to the prototype, the device is additionally equipped with a raw material granulator located in the feed loading unit, the first gas circuit being configured to supply the spent drying agent and flue gases to the mixing chamber to form the pyrolysis coolant to provide external heating of the pyrolysis chamber to obtain the spent pyrolysis coolant, the second gas circuit of the gas duct by gas blowing with the possibility of feeding the spent drying agent and the spent pyrolysis coolant into the mixing chamber to form a drying coolant and ensure drying of the granules to obtain dried granules and spent drying agent, and the third gas circuit is configured to supply the spent drying agent and flue gases generated by burning tar-free gas-vapor resulting from fractional condensation of pyrolysis vapor-gases to form a heat-transfer agent pyrolysis and providing internal heating of the pyrolysis chamber.

Preferably, the liquid biofuel extraction unit includes a condenser cooler, a centrifugal resin separator, and a liquid biofuel dropper.

The invention allows to increase the yield of liquid fuel from organic matter up to 31.6%, reduce the water content in it to 5%, increase the heat of combustion by 15-20% and reduce energy consumption per 1 kg of the resulting solid and liquid fuel, and also calls to receive output solid carbon-mineral product that can be used both as fuel and as fertilizer. This ensures the environmental safety of the process due to the burning of toxic volatile substances in the combustion chamber and the absence of burning of the resulting solid fuel (carbon mineral product).

Brief Description of the Drawings

The invention is illustrated by drawings.

Figure 1 presents a schematic diagram of a method of processing litter poultry.

Figure 2 presents a schematic diagram of a device, front view.

Figure 3 presents a schematic diagram of a device, a top view.

Figure 4 presents a schematic diagram of a device, side view.

Figure 5 presents a diagram of a first gas circuit.

Figure 6 presents a diagram of a second gas circuit.

7 is a diagram of a third gas circuit.

The implementation of the invention

According to the scheme in FIG. 1, wet raw materials are pre-granulated, preferably to a granule size of 5 to 6 mm in diameter and 20 to 35 mm in length, then the granules are dried at a temperature of 150 ° C, and then heated in a pyrolysis chamber without air at temperature 550 ° С at atmospheric pressure in the presence of a gas coolant. The pyrolysis products are converted to solid product and combined cycle gases. The pyrolysis steam gas is subjected to fractional condensation, as a result of which liquid fuel is obtained in the form of biomass. Resin-free pyrolysis steam-gas obtained as a result of fractional condensation is fed for combustion to form a gas coolant for pyrolysis and drying the processed raw materials. The spent drying agent is discharged into the atmosphere. The calcined pellet residue is cooled to a temperature of 150-200 ° C and selected in the form of a solid carbon-mineral product.

The device for processing the litter of the poultry farm (Figure 2-4) contains two chimneys 1, a hopper 2 of raw materials, a node 3 of the load / granulator of raw materials, flues 4, gas blowers 5, gas channels 6 for recycling the spent drying agent, shutters 7, a drying chamber 8, centrifugal resin separators 9, biomass droplet eliminators 10, condenser coolers 11, pyrolysis chamber 12, combustion chamber 13, blowers 14, carbon-mineral product discharge unit 15, clamps 16, mixing chamber 17, steam and gas extraction pipe 18, service areas 19 regulating the bed ki 20, the burner 21, the gas passage 22 entering the coolant.

The housing of the device includes two vertically arranged chambers that conditionally divide it into a zone of reverse-transverse-countercurrent drying of raw materials — chamber 8, a pyrolysis zone of raw materials — chamber 12, a liquid biofuel selection unit, consisting of condenser-coolers 11, centrifugal resin separators 9, drop catchers 10 biomass. The cameras are separated by pincers 16, which are a truncated cone. In the lower part of the device in the middle zone of the pyrolysis of raw materials, a combustion chamber 13 is installed, equipped with chimneys with control dampers 20 for supplying a pyrolysis coolant for heating the external walls and internal heating.

Inside the installation, three circuits are used (Figs. 5-7) for the circulation of combined-gas flows, the mass flow rates of which are regulated by the set operating factors for pressure and temperature:

- the first circuit (Figure 5) is designed to supply the spent drying agent and flue gases to the mixing chamber to form a pyrolysis coolant to provide external heating of the pyrolysis chamber to obtain the spent pyrolysis coolant;

- the second circuit (Fig.6) is designed to supply the spent drying agent and the spent pyrolysis coolant to the mixing chamber to form a drying coolant to ensure drying of the granules to obtain dried granules and spent drying agent;

- a third circuit (Fig. 7) for supplying the spent drying agent and flue gases generated by burning the tarless combined-cycle gases obtained by fractional condensation of the pyrolysis steam gas to form a pyrolysis coolant to provide internal heating of the pyrolysis chamber.

This allows you to adjust the volume of gas flows, set the pressure mode in the installation areas, and thereby maintain the necessary temperature conditions.

The device operates as follows. From the hopper 2 of the raw material through the node 3 loading / granulator of raw materials, the raw material enters the device where the drying chamber 8 and the pyrolysis chamber 12 pass sequentially. The resulting carbon-mineral product is partially cooled and is discharged from the device through the coal unloading unit 15.

The site 15 of the unloading of the carbon-mineral product is made in the form of a screw drive with external cooling.

When the device is operating, the resulting pyrolysis vapor and gas pyrolysis coolant are removed from the active thermal decomposition zone of the raw materials, the spent pyrolysis gas coolant is fed through the clamps 16 to form a drying agent, and the pyrolysis steam and gas through the nozzle 18, air-cooled condensers-coolers 11, centrifugal resin separators 9, drip catchers 10 of liquid biofuel and burners 21 are fed into the combustion chamber 13. There, air blowers are injected with air blowers 14 to burn about tarred combined-cycle gases. The combustion gases generated during combustion first heat the walls of the pyrolysis chamber 12, then partially go inside the pyrolysis chamber, and mainly after heating the chamber 12 into the mixing chamber 17 to form the drying coolant, and through the blinds 7, the drying coolant contacts the raw material in the transverse direction. Liquid biofuel is selected from condensers-coolers 11 and drop catchers 10 node selection liquid biofuel.

The separation of liquid biofuels from combined cycle pyrolysis gas with combined external and internal heating is necessary in order to reduce their heat output, i.e. the temperature of the flue gases should be no higher than 900-950 ° C, since the combustion temperature of non-tarred combined-cycle gases can reach 1300-1450 ° C, and this would greatly complicate the operation of the installation and would require the use of expensive materials in the furnace unit and the pyrolysis chamber.

After heating the unit and entering the operating mode, the amount of heat received from burning the tarless combined-cycle gases is sufficient to ensure a closed heat balance of drying and pyrolysis at a moisture content of the feedstock up to 55 rel. %

The high temperature of the flue gases entering the drying and pyrolysis sharply (4-6 times) accelerates the process of thermal processing of raw materials in the form of granules and increases the specific productivity of the installation, which allows us to develop a portable mobile installation up to 2 t / h using absolutely dry raw materials (a. ss).

Since the tarred pyrolysis combined cycle gases completely burn out, their emission into the atmosphere is excluded, which does not violate the ecology of the area.

Examples

To confirm the effectiveness of the claimed method, experimental studies of the process and general analyzes of solid and liquid ultraoxypyrolysis products obtained by processing the litter of the poultry farm according to the proposed method were carried out.

Table 1 shows the averaged data on the yield of ultraoxypyrolysis products from the litter of the poultry farm. Humidity of raw waste 54%. The mineral content of raw materials is 22.38% of a.s. The experiment was carried out at a drying temperature of 150 ° C and a pyrolysis temperature of 550 ° C.

Table 1 The yield of carbon-mineral product,% of raw materials The output of n / a gas + losses (by difference),% of raw materials The yield of liquid pyrolyate,% of raw materials 18.9 66.9 14.2 18.3 66.3 15.4 17.7 67.4 14.9 Average 18.3 66.9 14.8

Table 2 shows the characteristics of the carbon-mineral product obtained by ultraoxypyrolysis.

table 2 Characteristics of the carbon-mineral product No. Empty weight Weight of weighing box, g Ash mass Ash content,% Ash content,%,% Before ashing After ashing one 14.102 15,337 14,604 0.502 40,648 43,242 2 15,426 16,718 15,896 0.470 36,378 38,700 3 14,927 16,500 15,574 0.647 41,132 43,757 four 14,577 16,094 15,200 0.623 41,068 43,689 average 39.81 42.35

Table 3 shows the averaged data on the output of biomass from pyrolysates and the averaged data on the dehydration of liquid pyrolyzate obtained from the balance experiments of ultraoxypyrolysis.

Table 3 % biomass from feedstock % biomass from liquid pyrolyzate Mass Ref. raw materials, g Weight a.s., g Mass org. parts, g (from a.s.s.) The mass of liquid pyrolyzate, g Biomass mass, g % biomass from a.s. % biomass from org. parts 2239.8 1030.3 800,5 1485.9 253.0 11.3 17.0 24.6 31.6 ash, g 229.8

Table 4 shows the calorific value of the resulting liquid and solid fuels (biomass and biochar).

Table 4 Determined physical quantity Biomass Biocoal Highest specific combustion energy, Qs, kJ / kg 27991.45 15674.34 27983.60 15673.94 Arithmetic mean value, Qs, kJ / kg 27988 15674 124.5 - 124.5 - Flash point in open crucible, ° С Arithmetic average flash point in an open crucible, ° С 124.5 -

Table 5 shows the chemical composition of the resulting carbon-mineral product (biochar).

Table 5 Ingredient Amount, % Organic carbon 40.1 Inorganic carbon <0.1 Beryllium <0.0001 Boron 0,021 Manganese 0.018 Chromium <0.01 Nickel <0,0005 Cobalt <0,0003 Lead <0.001 Gallium <0,0005 Vanadium <0.001 Copper 0.15 Zinc 0.15 Molybdenum <0,0005 Yttrium <0.001 Lanthanum <0.001 Iron 0.26 Titanium 0,048 Calcium 6.2 Sodium 1.3 Potassium 0.3 Magnesium 1.7 Phosphorus 6.2 Sulfur <0.001

As can be seen from the above tables, the proposed invention can be used in the production of liquid biofuels with an energy intensity of up to ~ 28 MJ / kg and solid biofuels with an energy intensity of up to ~ 15.7 MJ / kg. In addition, the resulting carbon-mineral product with proper certification can be used as a fertilizer with the necessary content of macro- and microelements from the litter of poultry farms due to the presence of such mineral elements as sodium, potassium, calcium, phosphorus and others.

The claimed method and device can increase the yield of liquid fuel from organic matter up to almost 31.6% while reducing the water content in it to 5%, increase the heat of combustion by 15-20% and reduce energy consumption per 1 kg of solid and liquid fuel. The method also allows to obtain a solid carbon-mineral product with a yield of up to 15%, which can be used as fuel, as well as fertilizer. This ensures the environmental safety of the method due to the absence of burning solid fuel.

Claims (8)

1. A method of processing the litter of a poultry farm, in which the moisture-containing processed raw materials are dried, and then heated in a pyrolysis chamber without air access with the conversion of the pyrolysis products into a solid product and combined-cycle gases with their subsequent partial condensation into liquid biofuel, characterized in that the wet raw material is dried before drying granulate, the obtained granules are dried at a temperature of 150 ° C, and heating in the pyrolysis chamber is carried out at a temperature of 550 ° C in the presence of a gas coolant. 2. The method according to claim 1, characterized in that the pyrolysis is carried out at atmospheric pressure. 3. The method according to claim 1, characterized in that the wet material is granulated to a granule size of 5 to 6 mm in diameter and 20 to 35 mm in length. 4. The method according to claim 1, characterized in that the liquid fuel in the form of biomass is obtained from the pyrolysis steam and gas by fractional condensation. 5. The method according to claim 4, characterized in that the resin-free combined-cycle gases obtained as a result of fractional condensation are fed for combustion to form a gas coolant for pyrolysis and drying the processed raw materials. 6. The method according to claim 1, characterized in that the calcined residue of the granules is cooled to a temperature of 150-200 ° C and selected in the form of a solid carbon-mineral product. 7. A device for processing a litter of a poultry farm, comprising a vertically mounted housing including a drying chamber and a pyrolysis chamber, a feed loading unit, a carbon-mineral product unloading unit, a combustion chamber, at least one liquid biofuel extraction unit, a mixing chamber for forming a heat carrier drying connected through the first gas circuit with the combustion chamber, the first gas circuit made in the form of a gas duct with gas blowing, the second gas circuit and the third gas circuit made in the form of a gas duct with gas uvka, characterized in that it is additionally equipped with a feed granulator located in the feed loading unit, wherein the first gas circuit includes a combustion chamber connected to the flues, a mixing chamber, a drying chamber, while the first gas circuit is configured to supply a treated drying agent and flue gases into the mixing chamber to form a pyrolysis coolant to provide external heating of the pyrolysis chamber to obtain the spent pyrolysis coolant; the second gas circuit includes a gas blower gas duct, a mixing chamber and a drying chamber, while the second gas circuit is configured to supply the spent drying agent and spent pyrolysis coolant to the mixing chamber to form a drying coolant and allow drying of the granules to obtain dried granules and spent drying agent and the third gas circuit includes a gas duct and a pyrolysis chamber and is configured to supply spent drying agent and flue gases generated by t of burning tar-free gas-vapor obtained as a result of fractional condensation of pyrolysis steam-gases to form a pyrolysis coolant and provide internal heating of the pyrolysis chamber. 8. The device according to claim 7, characterized in that the node for the selection of liquid biofuel includes a condenser-cooler, a centrifugal resin separator and a droplet collector of liquid biofuel.

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