RU2803703C1 - Block plant for complete carbonization of organic substances - Google Patents

Abstract

FIELD: waste processing.

SUBSTANCE: invention relates to processing solid household, solid and liquid industrial waste. The block installation includes horizontal and shaft blocks built into a hot channel, to which the following are connected: a cyclone liquid waste purification unit, a tunnel furnace, a cooling unit, a cyclone filter unit, a retort-type unit, a smoke exhauster, a storage tank for cooled synthesis gas, and a chimney, wherein the installation additionally contains a manifold-distributor, sections for sorting, grinding, mixing and transporting the initial fuel mixture. A horizontal block is located on the upper ceiling of the hot channel, is made with a vaulted part and is equipped with a loading device, inspection windows, ash pan doors with an ash removal system. A shaft unit is equipped with a loading device, temperature sensors, an ash removal channel and is connected to the air supply channel, and is also connected to a cyclone filter unit, which is connected to the cooling unit. An ash removal channel is equipped with a container for collecting and transporting ash, the cooling unit is equipped with an analyser of the net calorific value of combustible gas and a sampler. A hot channel is equipped with holes and includes a combustion control device, an adjustable air supply damper and an ash pan door, as well as a pipeline for supplying “dirty” exhaust from the tunnel furnace and a retort-type unit, while inside the hot channel there is a screen superheater, a flame reflector, the ash pan door and the air supply channel to the shaft block. In the vaulted part there is a loading device, temperature sensors and ash pan doors with inspection windows. A retort-type block is equipped with a sealed lid and a discharge valve, and is also connected to the “dirty” exhaust supply pipeline, a smoke exhauster-driver made with the ability to create draft in the hot channel and vacuum in the vaulted part, as well as ensure the direction of hot gases from the hot channel into the chimney, made with a burner and a sampler. The cyclone liquid waste purification unit contains a dispenser and is in communication with the smoke exhauster, wherein the tunnel the furnace is equipped with a channel equipped with trolleys and includes burners connected to a manifold-distributor.

EFFECT: complete conversion of organic substances into synthetic gas with chemical suppression of the formation of hazardous compounds.

2 cl, 5 dwg

Description

The invention relates to the field of processing solid household, solid and liquid industrial waste and can be used as a source of providing independent heat and power supply to production facilities, greenhouses and residential areas of settlements without harmful effects on the environment by restoring energy resources contained in solid or liquid organic matter .

There is a known method for processing solid household and industrial waste to produce synthesis gas according to patent No. 2475677, in which the crushed waste is taken from the loading hopper by a feeding device, carbon dioxide and water are added to it, the resulting mixture is pushed through the heat supply pipes of the gasifier, heated to a temperature of 850- 1100°C and maintained at this temperature until gasification of the processed products is completed, flue gases are pumped sequentially through a heater of a mixture of air and part of the cooled flue gases using a smoke exhauster, which is then directed to the burner, an additional gas-water cooler and an adsorber in which carbon dioxide is separated from the flue gases , which is then separated from the adsorbent and sent by a blower to the inlet of the gasifier, after which the flue gases are divided into two streams, one of which is discharged into the atmosphere, the second is sent for mixing with the air supplied to the burner, and the gaseous and solid products formed in the gasifier are sent to a separation chamber irrigated with water, where sludge moistened and cooled with water to a temperature of 50-90°C is collected in the lower part of the separation chamber, from where it is removed by a screw device for further use or disposal, and the partially cooled gas, together with the water vapor formed in the separation chamber, is supplied for quenching into the gas cavity of a double-cavity quenching device, irrigated with water, cooling water is pumped through the second cavity of the quenching device from an external source, after which the mixture of irrigation water and the resulting condensate, accumulating in the lower part of the gas cavity of the quenching device, is drained into a water tank, and the gas leaving hardening device with a temperature of 60-90°C, additionally cooled with water from an external source in a surface heat exchanger to a temperature of 40-50°C, then taken with an exhauster and pumped through devices for cleaning dust, acid gases, sulfur compounds, resins and organic compounds, after whereby the purified gas is divided into two streams, one of which is sent as fuel to the burner, and the second stream is passed through a device for stabilizing the ratio of hydrogen and carbon monoxide, resulting in synthesis gas of the required composition, which is removed for further processing.

The disadvantage of the invention is:

- this installation requires preliminary drying and dehydration of the initial crushed waste, this is a separate energy-consuming operation;

- the use of adsorbers and carbon dioxide release devices increases the cost of waste processing, and consumables appear;

- a screw remover of wet sludge reduces the overall reliability of the installation.

A known installation for gasification of solid fuel according to patent No. 2333929 (C10B 49/10, op. 09.20.2008 Bulletin No. 26), including a supply source of crushed solid fuel, external and internal high-pressure vessels located coaxially to form between the vertical walls of the internal and outer vessels of the annular space, pipelines for supplying gasifying reagents and releasing the resulting gases, an air distribution grille is installed in the lower part of the outer vessel, and the annular space between the outer and inner vessels is filled with a fluidized layer of coolant material (heat releaser), while in the upper part of the outer high-pressure vessel There is a device for separating fuel carbonization products, which at its lower part is connected through a vertical pipe to an internal gasifier vessel, to the lower part of which a pipeline for supplying gasifying reagents is connected.

The disadvantage of the invention is:

- the device uses high-pressure vessels, approvals and permits for their operation will be required (complication, increased cost of the design);

- external sources of oxygen and steam are required;

- in the fluidized bed of the heat separator there is a high probability of the formation of liquid pyrolysis products. An explosive mixture is formed in a mixture of pyrolysis oil with oxygen, water vapor and air, and this cannot lead to anything good;

- in the inner vessel, liquid will also form as a pyrolysis product and increase the explosion hazard of the gasification process.

A known system for producing synthesis gas from biomass by carbonization according to patent No. 2525491 (C10J 3/66, op. 08/20/2014 Bulletin No. 23), including a section for pre-processing the source material of biomass, a carbonization furnace, a gasification furnace, a connecting pipeline for the carbonization furnace and gasification furnace, pneumatic conveying system, the upper part of the carbonization furnace is connected to the cyclone separator, the outlet end of the cyclone separator is connected to the combustion layer and charcoal storage hopper, the outlet end of the combustion layer is connected to the heat exchanger to heat the recycled pyrolytic gas, the outlet for the heated pyrolytic gas is connected to the carbonization furnace and the outlet of the chimney for waste flue gas that gives off heat is connected to the drying system.

The disadvantages of the system are:

- in a large number of individual devices connected by pneumatic transport;

- the installation is designed for the production, storage and consumption of charcoal (and only) coal for the purpose of subsequent production of synthetic gas.

The objective of the present invention is to safely obtain useful thermal energy and (or) synthesis gas.

The technical result is the complete conversion of organic substances into synthetic gas with chemical suppression of the formation of dangerous compounds, for example, dioxins and benzopyrenes, their derivatives and dust in the exhaust gases, as well as the use of thermal energy obtained as a result of the conversion process to maintain chemical reactions in plant units .

The specified technical result is achieved by a block installation for complete carbonization of solid organic substances, including horizontal and shaft blocks built into a hot channel, to which are connected a cyclone liquid waste purification unit, a tunnel oven, a cooling unit, a cyclone filter unit, a retort-type unit, a smoke exhauster, a storage tank for cooled synthesis gas, a chimney, wherein the installation additionally contains a manifold-distributor, areas for sorting, grinding, mixing and transporting the initial fuel mixture, a horizontal block is located on the upper ceiling of the hot channel, is made with a vaulted part and is equipped with a loading device, inspection windows, ash pan doors with an ash removal system, the shaft block is equipped with a loading device, temperature sensors, an ash removal channel and is connected to the air supply channel, and is also connected to a cyclone filter unit, which is connected to the cooling unit, the ash removal channel is equipped with a container for collecting and transporting ash , the cooling unit is equipped with a net calorific value analyzer and sampler, the hot channel is equipped with holes and includes a combustion control device, an adjustable air supply damper and an ash door, as well as a pipeline for supplying “dirty” exhaust from the tunnel furnace and the retort-type unit, while inside the hot channel there is a screen steam superheater, a flame reflector, an ash pan door and an air supply channel to the shaft block, in the vaulted part there is a loading device, temperature sensors and ash pan doors with inspection windows, the retort-type block is equipped with a sealed lid and a dump valve, and is also in communication with pipeline for supplying “dirty” exhaust, the smoke exhauster is designed to create draft in the hot channel and vacuum in the vaulted part, as well as ensure the direction of hot gases from the hot channel into the chimney, made with a burner and a sampler, the cyclone unit for cleaning liquid waste contains a dispenser and communicates with the smoke exhauster, wherein the tunnel oven is equipped with a channel equipped with trolleys, and includes burners connected to the distribution manifold.

It is advisable to cover the walls and under the hot duct with heat-insulating material, and make the upper ceiling from fire-resistant material.

The accompanying Figures 1-5 show the modular installation.

The modular installation consists of a horizontal block 1, designed to obtain thermal energy from the source organic material, and a shaft block 2, designed to produce synthetic gas from the source organic material, built into the hot channel 36, as well as terminal devices connected to them by pipelines:

- cyclone liquid waste disposal unit 3 for neutralization of liquid flammable waste (bottom residue);

- tunnel furnace 4 for neutralizing oil-contaminated soils, scale, oily chips, paints and varnishes in containers and similar carbon-containing materials;

- cooling unit 5, synthesized during the operation of a carbonization plant for combustible synthesis gas gas with a water filter;

- block of cyclone filters 6 for cleaning from mechanical impurities (inorganic dust) and neutralizing acidic impurities of HCl and HF;

- retort type unit 7 for thermal neutralization and (or) disposal of mixed waste and complex chemical compounds without access to oxygen;

- smoke exhauster - air draft stimulator 8 in the common channel;

- containers for storing cooled synthesis gas 9 at low pressure for its further use (gas holder);

- chimney 10 for removing exhaust gases from the installation (a mixture of nitrogen and carbon dioxide and excess heat). In the chimney 10 there is a burner for burning synthesis gas 11;

- sections for sorting 18, grinding 19, mixing 20 and transporting the initial fuel mixture 21, intended for grinding incoming waste and mixing the initial fuel mixture to the required size and uniformity, and then supplying the prepared fuel mixture to loading devices 14, 15.

All parts and blocks of the modular plant are equipped with temperature sensors to monitor process parameters.

Horizontal block 1 (Fig. 2) is made with a vaulted part 44, located on the upper ceiling of the hot channel 36. In the horizontal block 1, a horizontal gasification scheme for solid organic substances is implemented. Horizontal block 1 is equipped with inspection windows 24 and ash pan doors 22, 23. Temperature sensor readings (T°C) at measurement points 25 and 26 are used by thermostats to issue control commands to dampers - air supply regulators 35, as well as to remove ash from collections.

Mine block 2 (Fig. 3) is a shaft-type reactor equipped with temperature sensors 38, a loading device 15 and an ash removal channel 37.

To control the quality of the resulting synthesis gas at the outlet of the cooling unit 5, an analyzer of the net calorific value of the combustible gas 12 is provided, which is also used to control the production of synthesis gas.

The hot channel 36 is common to the entire installation and the hearth 1 and retort 2 blocks mounted on it.

At the right end of the hot channel 36 (Fig. 3) a combustion control device 27 and an adjustable damper of the air supply device 28 are installed. Below, also at the right end of the hot channel 36, there is an ash pan door 23. A supply pipeline is connected to the right end of the hot channel 36 dirty exhaust 13 from the tunnel furnace 4 and the retort-type block 7.

Inside the hot channel 36 there is a screen superheater 29 to produce water vapor with a temperature of 500°C and a flame reflector 30 that directs hot gases to the upper ceiling of the hot channel 36.

Along the hot channel 36, inside there is a rectangular air supply channel 31 to the horizontal block 2, designed to heat the air supplied to the reactor of the shaft block 2 to operating temperature. After the flame reflector 30 in the wall of the hot channel 36 there is an ash pan door 32.

The walls and under the hot channel 36 (Fig. 4) are separated from the environment by a layer of heat-insulating material 33.

The upper cover of the hot channel 36 is made of refractory material with an operating temperature of 1550 °C and high thermal conductivity. Closer to the right end of the hot channel 36 in the upper ceiling there are holes for the flow of gases into the hot channel and their effective mixing with air for the high-quality formation of a gas-air mixture.

At the left end of the vaulted part 44 of the horizontal block 1 there is a loading device 14 for feeding the starting organic materials inside; below there is a temperature sensor 33 and an ash pan door with an inspection window 34.

Further along the hot channel 36, a shaft block 2 is built into its body, which is a shaft-type reactor designed to produce synthetic gas from source organic substances.

The design of shaft block 2 implements a scheme for the reverse process of direct-flow gasification in a dense layer of solid organic substances. The initial mixture for gasification is fed into the reactor of the shaft block 2 through the loading device 15. The elements of the shaft block 2 are located so that the thermal energy of hot gases can be used for operational drying of organics and the production of products of chemical pyrolysis reactions. Air supply channel 31 is connected to retort unit 2 and allows air to be heated to operating temperature (300-400°C). Next, the air supply channel 31 is used for distribution over the zones of location of tuyeres 23 in the reactor of shaft block 2. Synthesis gas is supplied from shaft block 2 through pipeline 16 to the cyclone filter block 6 for pre-cooling and sedimentation of mechanical impurities, as well as neutralization of acids in the synthesis composition -gas. The cyclone filter unit 6 is connected by pipeline to the cooling unit 5 for final cooling and conditioning of the synthesis gas. At the outlet of the cooling unit 5, a sampler 12 is installed to monitor the composition of the exhaust gases.

The finished synthesis gas is sent to the distribution manifold 17 for further use.

Ash from the shaft block 2 is removed through the ash removal channel 37 as it accumulates and cools, ending up in the transportation container 45.

Further downstream, a retort-type block 7 is built into the body of the hot channel 36. Gaseous products formed during the thermal treatment of substances (for example, packaged drugs, hazardous medical waste) are removed from the retort-type block 7 through a relief valve and pipeline. Next, these gases enter the right end of the hot channel 36 into the “dirty” exhaust supply pipeline 13.

Organic waste or the original fuel mixture is loaded into a retort-type block 7 through a lid 42 that closes hermetically. The ash formed as a result of heat treatment plays the role of a dry seal and, as it accumulates, is removed through the ash removal channel 37 into a separate container for collection, transportation and burial.

A smoke exhauster-driver 8 is connected to the left end of the hot channel 36 through a pipeline, which creates draft in the hot channel 36 and a vacuum in the vaulted part 44, and on the other hand directs hot gases from the hot channel 36 into the chimney 10 and further into the atmosphere. A burner 11 is built into the chimney 10 for afterburning unused synthesis gas and also a sampler 12 for analyzing and monitoring the composition of the exhaust gases.

Synthesis gas, after cooling and conditioning in the cyclone filter unit 6 and the cooling unit 5, can be sent from the distribution manifold 17 to the cyclone liquid waste disposal unit 3, the tunnel oven 4 or to the gas holder 9. Excess synthesis gas is sent to the burner 11 for direct combustion in a chimney 10.

Cyclone liquid waste recycling unit 3 is a multi-section furnace in which wall circulation of flows of a mixture of combustible synthesis gas and air is organized.

From above, liquid flammable waste (bottom residue) is supplied to the second section 40 of the cyclone liquid waste disposal unit 3 through a dispenser 41 for thermal neutralization.

All undesirable factors and consequences during the thermal neutralization of liquid waste are thus minimized due to exposure to high temperatures and long exposure times. The generated heat is removed from the heat exchanger body of the cyclone liquid waste disposal unit 3 and is used to heat clean air or dry wet waste. The gases leaving the last section of the cyclone liquid waste disposal unit 3 are sent to the smoke exhauster 8.

Containers (trolleys) 46 with oil-contaminated soils and bagged paints and varnishes move along the channel of the tunnel kiln 4. Along the length of the channel of the tunnel furnace 4 there are burners connected to the manifold-distributor 17 of the synthesis gas. The flame from the burners is directed into the channel. This is how the materials are calcined in the containers of the tunnel furnace 4. The gases released during the calcination are removed from the channel of the tunnel furnace 4 by a smoke removal system. The smoke removal system includes a pipeline that directs gases from the tunnel furnace 4 into the “dirty” exhaust pipeline 13. Neutralized soils, etc., are removed from the containers and sent for disposal.

Synthesis gas stored in gas tank 9 can be used as fuel to power internal combustion engines, thermal boilers, gas microturbines, etc.

Operating principle of a modular installation.

To ensure a sustainable and stable result in the operation of a carbonization plant, the starting organic materials must be averaged in size and composition. For example, the organic mixture TOPAL-1 (RDF) (a mixture of plastic waste) fits the listed conditions. Such starting material must be relatively homogeneous, moderately moistened, crushed, and capable of being compressed. Morphologically, RDF contains carbon-containing substances: polyolefins (polymer films), cellulose, rubber, textiles, RDF, etc., therefore, raw materials for obtaining more high-calorie synthesis gas during subsequent combustion, in contrast to gas obtained, for example, from waste wood.

This initial organic material creates the so-called. product plug in loading devices 14, 15. The product plug blocks the circulation of gases and separates the products released during carbonization and thermal processing from the atmosphere of the horizontal block 1 and shaft block 2. Below in the ash removal channel 37 there are dry ash plugs that prevent the penetration of gases from reaction zones of horizontal block 1 and mine block 2 into the atmosphere.

The transformation of the averaged organic mixture into carbon (soot) in the horizontal block 1 begins at a temperature inside the vaulted part 44 above 300°C. To do this, the upper ceiling of the hot channel 36 of the vaulted part 44 and the entire hot channel 36 are heated before starting work with fuel loaded through the doors of the ash pans 22, 23 at the right end of the installation.

After heating, the electric motor of the smoke exhauster 8 is turned on, creating a vacuum inside the vaulted part 44 and in the hot channel 36. A draft arises and the air, through the adjustable dampers 35 located on top of the vaulted part 44, enters the chemical reaction zones.

Along with heating, the hot air penetrates through the tuyeres 48 into the vaulted part 44. Here, carbon monoxide CO is predominantly formed. The temperature inside the vaulted portion 44 rises rapidly. Further, the residual moisture in the starting material makes it possible to obtain additional hydrogen gas. In the reaction zone, products for the synthesis of methane and similar flammable gases appear.

Through aerodynamically shaped holes in the upper ceiling in the hot channel 36, a mixture of gaseous products from the vaulted part 44 is carried away by draft into the hot channel 36 and, mixing with air, burns. In this case, the flame temperature reaches temperatures above 1200 °C. The length of the hot channel 36 allows the combustion products of synthetic gas to be retained for a long time at a high temperature. This promotes the decomposition of unwanted impurities and soot into simple and non-hazardous compounds. In the hot channel 36, a flow of hot exhaust gas arises, which heats: the upper overlap of the hot channel 36, the screen superheater 29, the air supply channel 31, the reactor vessel of the mine block 2, the housing of the retort-type block 7. The exhaust gases are directed into the chimney 10.

Due to the thrust modes in the hot channel 36, complete combustion (re-oxidation) of carbon monoxide, methane and hydrogen occurs to carbon dioxide and water vapor. Complex organic compounds decompose to simpler ones at such temperatures. Halogens and sulfur from polymers react primarily into hydrogen. The soot has time to burn completely, mineral dust settles in the ash pans of the vaulted part 44 and the hot channel 36. The ash formed in the vaulted part 44 is also removed through the doors of the ash pans 22, 23.

The initial organic material loaded from above into the shaft block 2 through the loading device 15 is preheated and dried, the moisture evaporates and its carbonization begins. Heated air is supplied to the charring zone from the air supply channel 31 through the tuyere system 48. With a relative lack of oxygen, charring and intensive formation of soot (carbonization) occurs, and then, after the next addition of oxygen to the next reaction zone, the formation of carbon monoxide. The temperature in the gasification zone rises sharply. Water vapor at high temperatures interacts with existing carbon to produce hydrogen gas. Here, hydrogen bonds between halogens and sulfur. Along the way, methane is formed.

The mixture of flammable gases leaves the reactor of the shaft block 2 and is supplied to the cyclone filter block 6 and the cooling block 5, and then to the terminal devices.

Mine block 2 implements the principle of suppressing the formation of precursors of heavy and polyaromatic hydrocarbons.

The automatic control system for the processes of carbonization and thermal neutralization of hazardous waste is based on the readings of temperature sensors, air flow, and analyzers for the quality of the mixture of synthetic gas and waste gases. Several parameters, taken into account jointly by the control system, make it possible to obtain waste gases without harmful impurities at the outlet of the installation (within the maximum permissible concentration).

The main advantage of the presented installation is the common hot channel 36, on which the installation units are located.

This arrangement makes it possible to obtain separately: primary synthesis gas and the final mixture of flammable synthesized gases. The final synthesis gas used in the technological cycle and purified can be used to obtain its processing products - for example, methanol or dimethyl ether.

You can also receive:

- mineral substances, soils, scale, metal shavings purified from organic impurities;

- hot water for heating needs, hot water supply for the operation of various technological equipment, for example, flotation washers for degreasing crushed plastics;

- superheated steam for drying and calcining various materials, thermal disinfection of hazardous biological waste or generating electricity;

- synthesis gas for producing a highly active oxidizer in the decontamination reaction of waste of high hazard classes.

Excess heat obtained during exothermic chemical reactions in a common heat channel makes it possible to organize the neutralization of, among other things, liquid organic waste (for example, waste from the production of paints and varnishes) mixed with solid industrial waste.

Through the use of domestic ceramic materials, opportunities have been created for reactions to proceed at elevated temperatures (1350-1400°C). Heat from the reaction zone does not enter the external environment due to the well-thought-out thermal insulation of the plant blocks.

Unlike existing solutions, carbon conversion occurs with a relative lack of oxygen in the conversion zones, which prevents the formation of explosive mixtures. Separately, I would like to note that primary synthetic gas is low explosive in the presence of high-performance thrust in a common channel.

To prevent leakage of conversion products from the block casing, negative pressure is created around the reactor vessels.

Continuous loading of solid fuel or a mixture of organic substances into the reactor blocks is carried out by a loading device that excludes contact between the reactor zones and the environment. Ash removal is carried out through a channel with a dry seal from ash masses.

It has been practically determined that with increasing temperature in reactors, the depth of carbon conversion in organic substances and the yield of flammable gases increase, and the formation of harmful substances is significantly reduced.

In this case, the temperature in the reaction zones exceeds 1200 °C, the yields of H ₂ and CO tend to maximum values.

Tars and soot are completely gasified, and no harmful by-products are formed at all. This is the process of gradually suppressing the formation of toxic substances in exhaust gases. Excess heat from the common channel 36 of the installation is removed using a system of heat exchangers for the needs of external consumers.

Claims (2)

1. Block installation for complete carbonization of solid and liquid organic substances, including horizontal and shaft blocks built into a hot channel, to which are connected a cyclone liquid waste treatment unit, a tunnel oven, a cooling unit, a cyclone filter unit, a retort-type unit, a smoke exhauster, a storage tank for cooled synthesis gas, a chimney, wherein the installation additionally contains a manifold-distributor, areas for sorting, grinding, mixing and transporting the initial fuel mixture, a horizontal block is located on the upper ceiling of the hot channel, is made with a vaulted part and is equipped with a loading device, inspection windows, ash pan doors with an ash removal system, the shaft block is equipped with a loading device, temperature sensors, an ash removal channel and is connected to the air supply channel, and is also connected to a cyclone filter unit, which is connected to the cooling unit, the ash removal channel is equipped with a container for collecting and transporting ash , the cooling unit is equipped with a net calorific value analyzer and sampler, the hot channel is equipped with holes and includes a combustion control device, an adjustable air supply damper and an ash door, as well as a pipeline for supplying “dirty” exhaust from the tunnel furnace and the retort-type unit, while inside the hot channel there is a screen steam superheater, a flame reflector, an ash pan door and an air supply channel to the shaft block, in the vaulted part there is a loading device, temperature sensors and ash pan doors with inspection windows, the retort-type block is equipped with a sealed lid and a dump valve, and is also in communication with pipeline for supplying “dirty” exhaust, the smoke exhauster is designed to create draft in the hot channel and vacuum in the vaulted part, as well as ensure the direction of hot gases from the hot channel into the chimney, made with a burner and a sampler, the cyclone unit for cleaning liquid waste contains a dispenser and communicates with the smoke exhauster, wherein the tunnel oven is equipped with a channel equipped with trolleys, and includes burners connected to the distribution manifold. 2. Block installation for complete carbonization of solid organic substances according to claim 1, in which the walls and under the hot channel are lined with heat-insulating material, and the top floor is made of fire-resistant material.