WO2008002186A1

WO2008002186A1 - Plant for reprocessing solid combustible waste

Info

Publication number: WO2008002186A1
Application number: PCT/RU2007/000201
Authority: WO
Inventors: Boris Nikolaevich Ulko; Dmitry Semenovich Strebkov; Farit Salikhovich Burganov
Original assignee: Boris Nikolaevich Ulko; Strebkov Dmitrij S; Farit Salikhovich Burganov
Priority date: 2006-06-28
Filing date: 2007-04-24
Publication date: 2008-01-03
Also published as: RU2316696C1

Abstract

The invention relates to reprocessing solid combustible. The inventive method consists in supplying a combustible mixture principally consisting of a combustible gas and air to a high-temperature reactor (1) for burning said mixture in such a way that a working medium is formed, in transferring hot gases through a pipeline (2) to a an annular slotted channel (6) which is located between walls of a first pyrolysis chamber and is used as a heating chamber, in simultaneously leading the gas stream to a pipe (13), in heating the internal space of a first pyrolysis chamber (3), in removing the thus formed gaseous pyrolysis products through a branch pipe (10) and a solid residual to a bin (8), in simultaneously carrying out the pyrolysis of a sorted raw material supplied by a top pipe (17) in a second pyrolysis chamber (12), wherein said raw material is supplied, by shooting, to blades of a mixing device. The pyrolysis process is carried out in the presence of hydrogen contained in the working medium received from a fine disperser (14) and from the annular slotted clearance (6). The gaseous pyrolysis products are removed from the second pyrolysis chamber (12) through a branch pipe (18), whilst a solid residual is removed through a bin (16). Said invention makes it possible to reprocess industrial waste exhibiting different physicochemical characteristics.

Description

INSTALLATION FOR THE PROCESSING OF FLAMMABLE SOLID WASTE

Technical field

The invention relates to the field of processing of combustible solid household and industrial waste, including polyethylene, plastics, food waste, fabrics, dry biomass, woodworking waste, sawdust, bark, etc., with obtaining diesel fuel, gasoline as final products, synthesis gas.

State of the art

A device for processing solid waste is known [RF Patent N 2076272], containing a horizontally located housing, means for supplying raw materials and unloading coke residue, a heating chamber located on the outside of the housing with a furnace (high-temperature reactor) and means for supplying and burning fuel, air and output combustion products. The installation is equipped with different-sized movable jumpers attached to the upper wall of the housing, dividing its internal volume into zones of drying, pyrolysis and afterburning. The upper part of the afterburning zone is connected by an external channel to the lower part of the pyrolysis zone, the upper part of the pyrolysis zone is connected by an external channel to the lower part of the drying zone, and the upper part of the drying zone is connected by an external channel to the furnace. The disadvantage of this device is that with the heterogeneity of the feedstock received for processing, there are significant fluctuations in the quantity and calorific value of gaseous products released during pyrolysis and then transferred to the furnace of the device. And since the thermal potential of products burned in the furnace, then transferred by flue gases to the pyrolysis zone through the wall of the device, is the source of the bulk of the thermal energy necessary for of the pyrolysis process, either the process attenuates at too low calorie content of the raw material, or, on the contrary, its excessive intensification at high calorific value, leading to uncontrolled "acceleration" of the process and an unaccounted temperature increase, which may result in structural failure.

As a prototype, a device for processing solid waste was selected [RF Patent Ns 2132997], containing a horizontal body, means for feeding waste (auger) and unloading coke residue. Outside the casing there is a heating chamber connected to a high-temperature reactor with means for supplying and burning fuel and pyrolysis gas, air supply and output of combustion products. The walls of the casing from the side of the heating chamber are equipped with movable partitions, the axis of rotation of which are perpendicular to the longitudinal axis of the casing, and their width is equal to or less than the gap between the walls of the casing and the heating chamber. The distance between the axis of rotation of two adjacent partitions is equal to or less than their width. Partitions are equipped with bimetallic rotary devices. During the operation of the prototype device, the flue gases generated in the furnace during fuel combustion pass through the heating chamber and the processed waste located in the housing is heated through the walls of the furnace. As a result, the raw material is first dried, and then, as it warms up, it is pyrolyzed. Pyrolysis occurs in the presence of air, which is supplied by means of a special tool. Gaseous decomposition products enter a high-temperature reactor, replacing part of the fuel. The position of the partitions is determined by the temperature inside the case. At low temperatures, partitions partially overlap the internal volume of the casing, forming labyrinth passages for the movement of pyrosynthesis gas, which is directed in countercurrent to the supplied raw materials. At high temperatures, the partitions occupy a position that does not impede the direct passage of gas through the internal volume of the chambers. The main disadvantage of the prototype is that the resulting pyrosynthesis is used only for own needs to ensure the combustion process in the furnace. At the output of the device receive flue gases and coke and slag residue.

Disclosure of invention

The basis of the invention is the task of ensuring the processing of combustible waste to produce marketable products - hydrocarbons, namely gasoline, diesel fuel, combustible gases, as well as solid carbon-containing fractions (carbon black, coke and slag residue).

The problem is solved by changing the design of the installation. The plant for processing solid combustible waste includes a high-temperature reactor connected to a pyrolysis reactor. The installation differs from the prototype in that the pyrolysis reactor is vertically oriented and has two coaxially located pyrolysis chambers. Both cameras are equipped with mixing devices. The first pyrolysis chamber has an outer and inner coaxially located body with a slotted annular channel between them, which is a heating chamber and connected to a high-temperature reactor. The exit of the slotted annular channel is located inside the second pyrolysis chamber. The first pyrolysis chamber in the bottom has a hopper with a lock chamber for collecting and withdrawing coke residue. In the upper part of the first pyrolysis chamber there is a pipe for supplying raw materials and a pipe for exiting the pyrolysis products, equipped with a shut-off valve. In the axial zone of the first pyrolysis chamber is located at least one longitudinally oriented pipe, the entrance of which is located in the bottom of the heating chamber. The outlet of the pipe is equipped with a fine atomizer and is located in the bottom of the second pyrolysis chamber. In the upper part of the second pyrolysis chamber there is a pipe for supplying sorted raw materials and a pipe for the output of pyrolysis products. In the bottom of the second pyrolysis chamber there is a hopper for withdrawing the coke residue. Embodiments of the invention

In more detail, the invention is disclosed in the following implementation example and is illustrated by the Figure, which is a schematic representation of the installation.

Installation for processing solid combustible waste contains a high-temperature reactor 1, which is connected by a pipe 2 to the pyrolysis reactor. The pyrolysis reactor consists of two coaxially located pyrolysis chambers, with a common vertically oriented cylindrical water-cooled casing (not shown in the Figure). In one installation, two pyrolysis reactors can be connected to one high-temperature reactor.

The first chamber 3 of the pyrolysis reactor has an outer casing 4 and an inner casing 5 coaxial to it (construction “glass in glass”). Between the housings 4, 5 there is a slotted annular cylindrical channel 6, which is a heating chamber of the first pyrolysis chamber and is connected by a pipe 2 to a high-temperature reactor 1. A mixing device is located inside the first pyrolysis chamber 3 (the device itself is not shown, but its drive 7 is shown) . In the bottom of the body of the first pyrolysis chamber there is a hopper 8 for collecting and withdrawing coke residue, equipped with a lock chamber. In the upper part of the first chamber 3 there is a pipe 9 for supplying processed raw materials and a pipe 10 for outputting gaseous pyrolysis products. The pipe 10 is equipped with an adjustable shut-off valve (not shown in the Figure). A continuation of the housing 4 of the first chamber is the housing 11 of the second pyrolysis chamber 12, and the slotted annular channel 6 extends into the second pyrolysis chamber 13 into its bottom part. A longitudinally oriented pipe 13 is placed along the axis or in the axial region of the first pyrolysis chamber 3. Its inlet is located at the bottom of the heating chamber and, thus, it is connected to the high-temperature reactor 1. The outlet of the pipe 13 is equipped with a fine spray 14 and is located in the bottom of the second chamber 12palysis. In the first chamber 3 pyrolysis can several longitudinally oriented pipes should be placed, just like the pipe 13. The second pyrolysis chamber 12, like the first, is equipped with a mixing device (the device itself is not shown in the Figure, but its drive 15 is shown) and a hopper 16 for collecting and removing the coke residue. In the upper part of the second chamber 12 there is a pipe 17 for supplying sorted processed raw materials (solid combustible waste) and a pipe 18 for outputting the pyrolysis products.

Installation works as follows.

A combustible mixture consisting mainly of combustible gas (methane) and air with an excess of fuel (oxygen excess coefficient is cH), 5-0.6) is fed to a high-temperature reactor 1, where at a temperature of 1400-1600 ⁰ C combustion is carried out with the formation of a working fluid consisting of a mixture of gases: CO, CO ₂ , H _2, N _2; and other gases. The heated gases through the pipe 2 enter the slotted annular channel 6 between the walls of the first pyrolysis chamber, which is the heating chamber. At the same time, the heated gas stream rushes into the pipe 13. In this case, the internal volume of the first pyrolysis chamber is uniformly heated by radial counter flows: from the walls to the longitudinal axis and from the axial pipe 13 to the walls. Metals, stones, glass, dry plaster, sand, clay, etc. are preliminarily separated from solid waste, leaving combustible household waste intended for processing in the first pyrolysis chamber 3. If necessary, the purified raw materials are ground. The load goes from above through the nozzle 9. When strewn, the raw material falls on the blades of the mixing device and is further loosened and crushed. Upon reaching the operating mode, the temperature inside the first chamber 3 of pyrolysis reaches 400 ° - 500 ⁰ C, and the pressure is 0.1-2.0 MPa, and is determined by the adjustment of the shut-off valve. In the first pyrolysis chamber 3, high-speed heating of combustible raw materials occurs, accompanied by the destruction of high molecular weight components of the raw materials. The resulting gaseous pyrolysis products when the specified pressure is reached in the chamber are discharged through the pipe 10, because its shut-off valve is triggered. Further processing of the obtained gas phase of the pyrolysis products is carried out by traditional methods and is not the subject of the present invention. The solid coke-ash residues formed are poured into the hopper 8 and removed from it as they accumulate. In this case, the raw materials continue to be fed to the first chamber 3 for processing continuously.

The increased pressure created in the chamber 3 accelerates the dry pyrolysis process, improves the heat exchange between the walls of the reactor and the raw material, as well as within the volume of the raw material itself, since the mass density increases per unit volume. Thus, with increasing pressure in the chamber 3, the pyrolysis process is accelerated and improved, the process of intensification of the pyrolysis of the feedstock occurs, which improves the quality of the liquid fraction of diesel fuel. In this case, the pyrolysis process occurs without contact with the working fluid. At the same time, in the second chamber 12, pyrolysis of the sorted raw material takes place, which is supplied from the upper pipe 17. When strewn, the raw material falls onto the blades of the mixing device and is further loosened and crushed. The raw materials in the second chamber use polyethylene waste and wood waste (eg sawdust), while the amount of wood waste is at least 30%. The pyrolysis process occurs in the presence of hydrogen, which is present in the working fluid coming from a finely dispersed atomizer 14 and a slotted annular gap 6. With this organization of the pyrolysis of polyethylene and wood waste, gasoline and diesel fuel are formed up to 80% of the mass of processed raw materials and up to 11% of pyrolysis gas the rest is carbon black (carbon black). The raw materials in the second chamber 12 is fed continuously and the pyrolysis process is continuous. The temperature in the second chamber 12 is slightly lower - 390-430 ⁰ C. The heating and supply of the products of the high-temperature reactor is carried out by annular blasting from the bottom along the chamber walls (from the annular slot gap of the first chamber), and also introduced by blasting from the atomizer 14 at the end of the pipe 13. Thus, in the second chamber 12 pyrolysis occurs intensive movement of raw materials, both due to mechanical mixing, and due to the impact of turbulent gas flows. Pyrolysis occurs in a fluidized bed. Gaseous pyrolysis products from the second chamber

12 are discharged through the pipe 18, and the solid residue through the hopper 16. In the second chamber 12, it is possible to pyrolyze only sawdust or only polyethylene. During the pyrolysis of one polyethylene, the yield of gasoline and diesel fuel is three times less than in the presence of sawdust.

Separation into fractions obtained at the outlet of the gas-vapor mixture is carried out in the traditional way. During operation of the reactor, all parts of its body are cooled by passing refrigerant, for example, water in the gap between the walls of the casing.

The operation of the installation is tested on various raw materials. The following are test examples. In all examples, industrial or household waste was pre-ground in a vibratory mill to a fraction of 40 microns. The test results are summarized in tables.

JVb Example 1

Recycling unsorted waste, i.e. processing of household and industrial carbon-containing combustible waste in the first chamber of the pyrolysis reactor.

The temperature in the pyrolysis chamber is 400 ⁰ C, the pressure is atmospheric, and there is no working fluid (hydrogen) in the chamber.

JVb Example 2

Recycling unsorted waste, i.e. processing of household and industrial combustible waste in the first chamber of the pyrolysis reactor.

The temperature in the chamber is 400 ⁰ C, the pressure is atmospheric, and there is no working fluid (hydrogen) in the chamber.

JVb Example 3

The temperature in the chamber is 450 ^° C, the pressure is atmospheric, and there is no working fluid (hydrogen) in the chamber.

JVb Example 4

Recycled sorted waste in the second chamber of the pyrolysis reactor. As the polymers used crushed bottles, films and other waste

The temperature in the second chamber is 360 ⁰ C, the pressure is 0.2 MPa. The pyrolysis process was similar in contact with the working fluid, i.e. in the presence of hydrogen.

JVb Example 5

Processing sorted garbage in the second chamber of the pyrolysis reactor, crushed bottles, films and other wastes were used as polymers.

Pyrolysis temperature 400 ⁰ C, pressure 0.2 MPa.

The pyrolysis process was similar in contact with the working fluid, i.e. in the presence of hydrogen.

Thus, the two-chamber design of the pyrolysis reactor allows the processing of solid household and industrial waste with various physicochemical characteristics. At the same time, the output is marketable products - hydrocarbons, namely, gasoline, diesel fuel, combustible gases, and solid carbon fractions

(carbon black, coke and slag residue) with a high yield of useful products.

An example is Kaliningrad, in which out of 1000 tons of the daily waste rate, 10% is wood waste and polyethylene waste. From this amount of solid combustible waste, you can get 80 tons of high-quality gasoline and diesel fuel.

Claims

CLAIM

1. Installation for processing solid combustible waste, comprising a high-temperature reactor connected to a pyrolysis reactor having a heating chamber, characterized in that the pyrolysis reactor is vertically oriented and has two coaxially located pyrolysis chambers equipped with mixing devices, the first pyrolysis chamber has outer and inner coaxial housings with a slotted annular channel between them, which is a heating chamber, which is connected to a high-temperature reactor m, the exit of the slotted annular channel is located inside the second pyrolysis chamber, the first pyrolysis chamber in the bottom has a hopper with a lock chamber for collecting and removing coke and slag residue, in the upper part of the first pyrolysis chamber there is a pipe for supplying raw materials and a pipe for outputting pyrolysis products equipped with a shut-off with a valve, in the axial region of the first pyrolysis chamber, at least one longitudinally oriented pipe is located, the inlet of which is located in the bottom of the heating chamber, and the pipe outlet, equipped with finely divided sprayer, located in the bottom of the second pyrolysis chamber, with the top of the second chamber is a pyrolysis tube for supplying raw materials sorted and exit pipe for pyrolysis products and has a hopper for outputting koksoshlakovogo residue in the bottom of the second part of the pyrolysis chamber.