Low-carbon synergistic utilization device and method for multi-source solid waste and organic solid waste

Abstract

The invention discloses a multi-source solid waste and organic solid waste low-carbon synergistic utilization device, which comprises a pyrolysis gasification device, an organic solid waste treatment device, a multi-source solid waste treatment device and an organic solid waste treatment device, the pre-reduction device is used for pre-treating dust sludge; the final reduction smelting device is used for smelting the pre-reduction material reduced by the pre-reduction device; and the coal gas mixing and adjusting device is connected with the pyrolysis and gasification device and the final reduction smelting device and is used for conveying the mixed coal gas to the pre-reduction device. The invention further discloses a low-carbon synergistic utilization method of the multi-source solid waste and the organic solid waste. The problem of harmful elements in the metal smelting process is solved, carbon emission in the smelting process is reduced, and a collaborative solution of metal and organic solid waste is provided.

Description

Technical Field

[0001] The present invention relates to the field of coordinated treatment and resource utilization of metal and organic solid wastes, specifically the coordinated treatment and resource utilization of solid wastes, organic solid wastes and biomass materials generated in the metal smelting production process, and more specifically, to a low-carbon coordinated utilization device and method for multi-source solid wastes and organic solid wastes. Background Art

[0002] A large amount of various iron-containing dust, sludge, copper slag and lead-zinc slag with utilization value will be generated in the process of steel and nonferrous metal production. They are mainly dust and sludge from sintering, blast furnace, electric furnace and converter processes in steel production, iron scale in steel rolling process, lead-zinc slag, copper slag, tailings, etc. in nonferrous metal production process. For a long time, most of the iron-containing dust in these steel production processes is directly returned to sintering for utilization after recycling. Among them, harmful elements (zinc, lead, potassium, sodium, etc.) will continue to be enriched in the production cycle. In addition, the proportion of waste galvanized sheets used in steelmaking is increasing, which leads to a gradual increase in the zinc content in the above-mentioned iron-containing dust materials. The return of high-zinc dust to sintering will cause a high zinc load in the blast furnace, affecting the production of the blast furnace and the life of refractory materials. Most of the tailings and slag in nonferrous metal production are stored and treated, causing environmental pollution and waste of resources.

[0003] The traditional metallized pellets produced by direct reduction process of steel dust are used as semi-finished products for blast furnace and converter reuse due to low metallization rate and many impurities. However, due to the high powderization rate, the residual zinc still has a great impact on the permeability and refractory of blast furnace. When entering the converter, the impurity content is high and the metallization rate is low, resulting in a large amount of converter slag and low metal recovery rate, which does not maximize the value of metallic iron and smelting slag. Under the increasingly stringent environmental protection requirements, it is crucial for enterprises to improve the efficiency of solid waste resource utilization and achieve economic benefits, in line with the current sustainable development requirements of energy conservation, environmental protection and comprehensive resource utilization. At the same time, since coke powder and coal are used as reducing agents in the reduction process, converter gas and coke oven gas are used as fuel, not only the carbon emissions are high, but also there will be no converter gas and coke oven gas in short-process steel mills in the future. Or in the treatment of iron-containing zinc tailings and tailings of non-ferrous enterprises, there is no gas available, resulting in great limitations in the process.

[0004] At present, a lot of research and experiments have been carried out in the steel industry on multi-source organic solid waste such as biomass, waste tires, and waste plastics. According to estimates, the current national organic waste resources are about 6.3 billion tons (equivalent to about 100 million to 120 million tons of standard coal), most of which are mainly landfilled and incinerated, with low resource utilization and obvious NIMBY effect. Applying organic solid waste to the direct reduction process of rotary hearth furnaces to replace fossil fuels is an important breakthrough in promoting a clean and low-carbon energy structure. Summary of the invention

[0005] In view of the defects existing in the prior art, the purpose of the present invention is to provide a low-carbon coordinated utilization device and method for multi-source solid waste and organic solid waste, which solves the problem of harmful elements in the metal smelting process, reduces carbon emissions in the smelting process, and provides a coordinated solution for metal and organic solid waste.

[0006] To achieve the above object, the present invention adopts the following technical solution:

[0007] The first aspect of the present invention provides a low-carbon synergistic utilization device for multi-source solid waste and organic solid waste, comprising:

[0008] Pyrolysis gasification device, used for pyrolysis of biomass and organic solid waste;

[0009] Pre-reduction device, used for pre-treatment of dust and mud;

[0010] A final reduction smelting device, used for smelting the pre-reduction raw materials reduced by the pre-reduction device;

[0011] The coal gas mixing and regulating device is connected to the pyrolysis gasification device and the final reduction smelting device, and is used to send the mixed coal gas to the pre-reduction device.

[0012] Preferably, the pyrolysis gasification device adopts a fixed bed or fluidized bed form, including a batching and feeding device, a pyrolysis gasification furnace, a coal gas temperature / composition regulating device and a coal gas dust removal device which are connected in sequence.

[0013] Preferably, the pre-reduction device is in the form of an annular pre-reduction furnace, including a batching device, a ball pressing device, a drying device, an annular pre-reduction furnace device and a discharge device connected in sequence;

[0014] The batching device is communicated with the outlet of the pyrolysis gasification furnace.

[0015] Preferably, the annular pre-reduction furnace device is also connected to a flue gas treatment device;

[0016] The smoke treatment device is provided with a smoke exhaust fan.

[0017] Preferably, the final reduction smelting device adopts an electric heating smelting furnace;

[0018] The inlet of the electric heating type melting furnace is connected in sequence with a batching system and a feeding device; and

[0019] It is also equipped with original agent spraying device and hot charging system;

[0020] The outlet of the electric smelting furnace is provided with an iron / slag discharging device;

[0021] The electric heating melting furnace is also provided with a gas dust removal device;

[0022] The coal gas dust removal device is provided with a pressure regulating device.

[0023] The shrink-fit system is communicated with the discharge device.

[0024] The second aspect of the present invention provides a method for low-carbon coordinated utilization of multi-source solid waste and organic solid waste, using the low-carbon coordinated utilization device of multi-source solid waste and organic solid waste provided by the first aspect of the present invention to perform the following steps:

[0025] S1, organic solid waste and biomass are transported to the batching and feeding device, and the composition and calorific value are analyzed to determine the proportion of various raw materials. After the gasification method is selected according to the calorific value and composition, the raw materials are transported to the pyrolysis gasification furnace;

[0026] S2, the organic solid waste and biomass undergo pyrolysis reaction with oxygen in the pyrolysis gasification furnace to produce pyrolysis gas and pyrolysis gasified carbon;

[0027] S3, the waste containing iron dust and mud is pre-treated, and then a binder and pyrolysis gasified carbon or a set amount of reducing agent is added, and the waste is pressed into balls by the ball pressing device, and then dried by the drying device and then enters the annular pre-reduction furnace device for pre-reduction;

[0028] S4, the annular pre-reduction furnace device uses pyrolysis gas as fuel, and the reduced pre-reduction raw materials are briquette or cooled or directly hot-charged into the electric heating smelting furnace for reduction and smelting into molten iron and slag;

[0029] S5, the flue gas of the annular pre-reduction furnace is recovered through waste heat and collected by a dust collector to obtain a zinc oxide-rich product;

[0030] S6, the byproduct gas of the electric smelting furnace and the pyrolysis gas are used together as fuel for the annular pre-reduction furnace to provide heat for the process of the annular pre-reduction furnace.

[0031] Preferably, in step S2, the pyrolysis gasification furnace uses pure oxygen or air for gasification;

[0032] The gasification temperature is 500~800℃;

[0033] The calorific value of gasification gas is 1500kcal / Nm 3 above.

[0034] Preferably, the coal gas temperature / composition regulating device is provided at the outlet of the pyrolysis gasification furnace, and the coal gas temperature / composition is regulated by introducing steam or oxygen.

[0035] Preferably, in step S4, the pre-reduction temperature of the annular pre-reduction furnace device is between 1050°C and 1300°C, and the discharge temperature is above 1000°C.

[0036] Preferably, in step S4, the reduction smelting temperature of the electric smelting furnace is between 1500°C and 2000°C.

[0037] Preferably, the step S5 specifically includes:

[0038] The flue gas discharged from the annular pre-reduction furnace enters the settling chamber, the waste heat boiler and the heat exchanger in sequence for cooling, and enters the dust collector to collect the zinc dust in the flue gas. The flue gas after dust removal is finally extracted through the exhaust fan.

[0039] The present invention provides a low-carbon coordinated utilization device and method for multi-source solid waste and organic solid waste. A pyrolysis gasification furnace is used to generate gas, metal solid waste is used as raw material for pre-reduction, and then an electric heating smelting furnace is used for final reduction. The metallized pellets produced in the pre-reduction furnace are smelted and the slag and iron are separated. The metallized pellets are melted and converted into molten iron products. This not only solves the problems of high impurity content and high pulverization rate of metallized pellets used in traditional blast furnaces, but also reduces the carbon used for combustion and heating compared with blast furnaces. Not only products are produced directly, but also carbon emissions from molten iron are reduced. Iron-containing solid waste and organic solid waste can be synergistically disposed of and source-utilized to produce molten iron and zinc oxide-rich products. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the structural framework of the low-carbon collaborative utilization device of the present invention;

[0041] Figure 2 It is a schematic flow diagram of the low-carbon collaborative utilization method of the present invention. DETAILED DESCRIPTION

[0042] In order to better understand the above technical solution of the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0043] Combination Figure 1 As shown, the present invention provides a low-carbon synergistic utilization device for multi-source solid waste and organic solid waste, comprising:

[0044] The pyrolysis gasification device 100 is used for pyrolysis of biomass and organic solid waste. The pyrolysis gasification device 100 adopts a fixed bed or fluidized bed form, and includes a batching and feeding device 101, a pyrolysis gasification furnace 102, a coal gas temperature / component adjustment device 103 and a coal gas dust removal device 104 which are connected in sequence.

[0045] The pre-reduction device 200 is used for pre-treatment of dust and mud. The pre-reduction device 200 is in the form of an annular pre-reduction furnace, and includes a batching device 201, a pelletizing device 202, a drying device 203, an annular pre-reduction furnace device 204 and a discharge device 205 which are connected in sequence.

[0046] The batching device 201 is connected to the outlet of the pyrolysis gasification furnace 102 .

[0047] The annular pre-reduction furnace device 204 is also connected to a flue gas treatment device 206 , and a smoke exhaust fan 207 is arranged on the flue gas treatment device 206 .

[0048] The final reduction smelting device 300 is used to smelt the pre-reduced raw materials reduced by the pre-reduction device 200. The final reduction smelting device 300 adopts an electric heating type smelting furnace 301, and the inlet of the electric heating type smelting furnace 301 is connected in sequence with a batching system 302 and a feeding device 303, and is also provided with an original agent blowing device 304 and a hot charging system 305, and the hot charging system 305 is connected with the discharge device 205; the outlet of the electric heating type smelting furnace is provided with an iron / slag discharge device 306.

[0049] A gas dust removal device 307 is also provided on the electric heating smelting furnace 301 , and a pressure regulating device 308 is arranged on the gas dust removal device 307 .

[0050] The coal gas mixing and regulating device 400 is connected to the pyrolysis gasification device 100 and the final reduction smelting device 300, and is used to send the mixed coal gas to the pre-reduction device 200.

[0051] Combination Figure 2 As shown, the present invention also provides a low-carbon collaborative utilization method for multi-source solid waste and organic solid waste, and the low-carbon collaborative utilization device of the present invention is used to perform the following steps:

[0052] S1, the raw materials are organic solid waste and biomass, which are transported to the batching and feeding device 101, and the batching and feeding device 101 batches the raw materials according to their composition and calorific value, and selects a gasification method according to the calorific value and composition;

[0053] S2, the organic solid waste and biomass undergo pyrolysis reaction with oxygen in the pyrolysis gasification furnace 102 to produce pyrolysis gas and pyrolysis gasified carbon;

[0054] S3, after pre-treatment, wastes such as iron dust and mud are added with a binder and pyrolysis gasified carbon or a certain amount of reducing agent, and then pressed into balls by a ball pressing device 202, and then dried by a drying device 203 and enter an annular pre-reduction furnace device 204 for pre-reduction;

[0055] S4, the annular pre-reduction furnace device 204 uses pyrolysis gas as fuel, and the reduced pre-reduction raw materials are briquette or cooled or directly hot-charged into the electric heating melting furnace 301 for reduction and melting into molten iron and slag;

[0056] S5, the flue gas from the annular pre-reduction furnace 204 is recovered through waste heat and collected by a dust collector to obtain a zinc oxide-rich product;

[0057] S6, the byproduct gas of the electric smelting furnace 301 and the pyrolysis gas are used together as fuel for the annular pre-reduction furnace 204 to provide heat for the process of the annular pre-reduction furnace 204.

[0058] In the above step S2, the pyrolysis gasification furnace 102 uses pure oxygen or air for gasification, the gasification temperature is controlled at 500-800°C, and a certain amount of steam is introduced to bring in heat and adjust the gas composition, and the calorific value of the gasified gas is controlled at 1500kcal / Nm 3 above.

[0059] A coal gas temperature / composition regulating device 103 is provided at the outlet of the pyrolysis gasification furnace 102, and the coal gas temperature / composition is regulated by introducing steam or oxygen to ensure that the macromolecular compounds (tars) in the coal gas are completely decomposed.

[0060] In the above step S4, the annular pre-reduction furnace device 204 uses the coal gas generated by the pyrolysis gasification furnace 102 and the electric smelting furnace 301 as fuel. The pre-reduction temperature of the annular pre-reduction furnace device 204 is between 1050°C and 1300°C, which reduces part of the metal oxides in the dust to metals, and the low-melting-point elements enter the flue gas and are enriched and recovered in the flue gas treatment device 206.

[0061] The annular pre-reduction furnace device 204 is provided with a feeding device, a combustion system, a transmission mechanism and a discharging system. The metal dust is reduced in the annular pre-reduction furnace device 204, the reduction rate is above 70%, and the discharging temperature is controlled above 1000°C.

[0062] The high-temperature flue gas (1000℃~1250℃) discharged from the annular pre-reduction furnace 204 enters the settling chamber, the waste heat boiler and the heat exchanger in sequence for cooling, and enters the dust collector to collect the zinc dust in the flue gas. The flue gas after dust removal is finally extracted through the exhaust fan 207.

[0063] In the above step S4, the pre-reduced raw materials after reduction in the annular pre-reduction furnace device 204 are added to the electric smelting furnace 301 through the discharging device 205 under high temperature. The electric smelting furnace 301 adds a certain proportion of reducing agent and flux through the batching system 302 and the reducing agent blowing device 304. According to the demand for molten iron, different proportions of scrap steel are added. The added furnace materials are heated, melted and reduced in the annular pre-reduction furnace device 204. The reduction smelting temperature is controlled at 1500-2000°C to reduce and smelt the pre-reduced raw materials into molten iron.

[0064] The electric smelting furnace 301 produces coal gas as a by-product during the smelting process. The coal gas is first introduced into the coal gas dust removal device 307 (gravity dust collector or cyclone dust collector) by the induced draft fan for rough dust removal. The coal gas after dust removal enters the pre-reduction furnace as fuel or is mixed with the coal gas from the pyrolysis gasification furnace as fuel for the annular pre-reduction furnace device 204.

[0065] A pressure regulating device 308 is provided on the coal gas dust removal device 308, or a pressure regulating device 308 is directly provided on the electric heating smelting furnace 301. The pressure regulating device 308 controls the pressure inside the electric heating smelting furnace 301. The pressure regulating device 308 can utilize the flue gas induced draft fan of the pre-reduction furnace or be provided separately. The furnace of the electric heating smelting furnace 301 is controlled to have a slight negative pressure. The coal gas is drawn out through the pressure regulating device 308 and sent to the process of the pre-reduction device 200 for drying or combustion in the annular pre-reduction furnace device 204.

[0066] Example

[0067] Refer to Figure 1 As shown, this embodiment provides a low-carbon coordinated utilization device for multi-source solid waste and organic solid waste, comprising:

[0068] The pyrolysis gasification device 100 is used for pyrolysis of biomass and organic solid waste. The pyrolysis gasification device 100 adopts a fixed bed or fluidized bed form, and includes a batching and feeding device 101, a pyrolysis gasification furnace 102, a coal gas temperature / component adjustment device 103 and a coal gas dust removal device 104 which are connected in sequence.

[0069] The pre-reduction device 200 is used for pre-treatment of dust and mud. The pre-reduction device 200 is in the form of an annular pre-reduction furnace, and includes a batching device 201, a pelletizing device 202, a drying device 203, an annular pre-reduction furnace device 204 and a discharge device 205 which are connected in sequence.

[0070] The batching device 201 is connected to the outlet of the pyrolysis gasification furnace 102 .

[0071] The annular pre-reduction furnace device 204 is also connected to a flue gas treatment device 206 , and a smoke exhaust fan 207 is arranged on the flue gas treatment device 206 .

[0072] The final reduction smelting device 300 is used to smelt the pre-reduced raw materials reduced by the pre-reduction device 200. The final reduction smelting device 300 adopts an electric heating type smelting furnace 301, and the inlet of the electric heating type smelting furnace 301 is connected in sequence with a batching system 302 and a feeding device 303, and is also provided with an original agent blowing device 304 and a hot charging system 305, and the hot charging system 305 is connected with the discharge device 205; the outlet of the electric heating type smelting furnace is provided with an iron / slag discharge device 306.

[0073] A gas dust removal device 307 is also provided on the electric heating smelting furnace 301 , and a pressure regulating device 308 is arranged on the gas dust removal device 307 .

[0074] The coal gas mixing and regulating device 400 is connected to the pyrolysis gasification device 100 and the final reduction smelting device 300, and is used to send the mixed coal gas to the pre-reduction device 200.

[0075] Organic solid waste and biomass are transported to the batching and feeding device 101 by car. The composition and calorific value analysis are carried out before batching. The proportions of various raw materials are determined according to the composition and calorific value. The batching and feeding device 101 includes a silo and quantitative feeding facilities. The prepared raw materials are added to the feeding silo of the pyrolysis gasification furnace 102 via a belt conveyor or a bucket elevator, and then added to the pyrolysis gasification furnace 102 via a screw feeder.

[0076] The pyrolysis gasification furnace 102 is a fixed bed or fluidized bed, using air or oxygen for gasification, adding some steam to adjust the gas composition and bring in some heat, organic solid waste and biomass undergo pyrolysis reaction with oxygen in the pyrolysis gasification furnace 102, partial combustion provides the heat required for pyrolysis, the gasification temperature is controlled at 500-800°C, and a certain amount of steam is introduced to bring in heat and adjust the gas composition, and the calorific value of the gasified gas is controlled at 1500kcal / Nm 3 As mentioned above, oxygen or air is provided with flow and pressure regulating devices, and the supply amount of oxygen and air is adjusted according to the ingredients and the temperature of the pyrolysis gasification furnace 102 .

[0077] A gas temperature / component regulating device 103 is provided at the outlet of the pyrolysis gasification furnace 102. The gas temperature / component regulating device 103 is provided with air and oxygen nozzles. The outlet temperature of the gas is adjusted by the reaction of oxygen and pyrolysis gas. A calorific value meter is provided at the outlet of the gas temperature / component regulating device 103. The calorific value meter and temperature are used to ensure that macromolecules such as tar in the gas are completely decomposed and the required calorific value of the gas is achieved.

[0078] The adjusted coal gas is sent to the coal gas mixing and adjusting device 400 after being dust-removed by the coal gas dust removal device 104 , and is used as the fuel of the pre-reduction device 200 . The coal gas calorific value analyzer can be arranged after the coal gas dust removal device 104 .

[0079] The various dust, coke powder, binder and other raw materials required by the pre-reduction device 200 are transported to the batching device 201 by tank trucks, and the dust removal ash and pyrolytic carbon of the pyrolysis gasification furnace 102 are transported to the batching bin of the pre-reduction device 200 via a pneumatic conveying device. The batching device 201 includes a dust receiving device, a silo, a feeding device and a batching scale. After being mixed according to the proportion, the mixed materials are sent to the ball pressing device 202 through a conveying facility.

[0080] The ball pressing device 202 includes a ball pressing buffer bin, a quantitative feeder, a ball pressing machine, and a screening machine. The mixed raw materials are pressed into green balls under the combined effect of compression force and adhesive force of the binder in the ball pressing machine. The qualified green balls are small balls with a particle size greater than or equal to 8 mm, and the unqualified green balls are sent back to the return bin through a belt conveyor. The pressed green balls are sent to the drying device 203 for drying.

[0081] The drying device 203 adopts two types of chain grate machine and mesh belt dryer. The qualified green balls after screening enter the mesh belt dryer for drying. After drying, the moisture content of the green balls will be reduced from 6% to below 1%. The dried green balls enter the pre-reduction device 200 for pre-reduction.

[0082] The pre-reduction device 200 adopts an annular pre-reduction furnace device 204. The raw balls are evenly spread on the furnace bottom through a feeding device. The annular pre-reduction furnace device 204 is heated by a burner. The burners are arranged on the inner and outer sides of the annular pre-reduction furnace device 204. The coal gas of the pyrolysis gasification furnace 102 and the coal gas of the electric smelting furnace 301 are used as fuel. The annular pre-reduction furnace device 204 rotates at the furnace bottom and is driven mechanically by the furnace bottom. The furnace chamber and the burner are fixed. The reduction of the charge is completed after the furnace bottom rotates one circle and is discharged from the annular pre-reduction furnace device 204 through the discharging device 205.

[0083] The pre-reduction temperature of the annular pre-reduction furnace device 204 is controlled at 1050℃~1300℃, and part of the metal oxides in the dust are reduced to metals with a reduction rate of more than 70%. The discharge temperature is controlled at more than 1000℃, and the low-melting-point elements enter the flue gas and are enriched and recovered in the flue gas treatment device 206.

[0084] The high-temperature flue gas of 1000℃~1250℃ discharged from the annular pre-reduction furnace device 204 enters the flue gas treatment device 206 and the exhaust fan 207 and is then discharged. The flue gas treatment device 206 includes a settling chamber, a waste heat boiler and a bag dust collector. The flue gas is cooled in the flue gas treatment device 206 to about 200℃ and enters the bag dust collector to collect zinc dust in the flue dust. The flue gas after dust removal is finally extracted through the exhaust fan 207.

[0085] The pre-reduced metallized pellets reduced by the annular pre-reduction furnace device 204 are discharged through the discharge device 205 at a temperature of about 1000° C. to 1100° C. and are added to the final reduction smelting device 300 through the heat transport device 305 .

[0086] The final reduction smelting device 300 adopts an electric heating smelting furnace 301, including a furnace body, a water-cooled furnace cover, a gas system, an electrode lifting device, a hydraulic system, a cooling water system, a pneumatic system, and a short-circuit system. Electrodes are used to provide heat for the smelting process, the furnace shell is cooled by water, refractory materials are built inside the furnace body, and iron holes and slag holes are provided for tapping iron and slag.

[0087] The main raw material of the electric smelting furnace 301 is the pre-reduced raw material after reduction in the pre-reduction furnace. It is added to the electric smelting furnace 301 through the discharge device 205 under high temperature, which significantly reduces the energy consumption of the final reduction furnace. The electric smelting furnace 301 adds a certain proportion of reducing agent and flux through the batching system 301 and the reducing agent blowing device 304. According to the demand for molten iron, different proportions of scrap steel are added. The added charge is heated, melted and reduced in the electric smelting furnace 301. The reduction smelting temperature is controlled at 1500℃~2000℃ to reduce and smelt the pre-reduced raw material into molten iron.

[0088] The electric smelting furnace 301 can be equipped with scrap steel materials according to demand, using blue charcoal, coke, biomass carbon, etc. as reducing agents, and limestone, dolomite and silica as flux. The raw materials of the electric smelting furnace 301 are transported to the batching system 302 by car, including a batching bin, a quantitative feeder, a weighing device, etc. The prepared raw materials are transported to the feeding device 303 by a belt conveyor or a bucket elevator, and added to the electric smelting furnace 301 through the feeding device 303. When the hot delivery device 305 is overhauled or the feeding device 303 is changed, the metallized pellets produced by the annular pre-reduction furnace device 204 can be cooled by a cooler, and the cold pre-reduced metallized pellets can be added to the electric smelting furnace 301 by the feeding device 303. The electric smelting furnace 301 can use block or powder reducing agents, and carbon powder and other powder reducing agents can be sprayed into the electric smelting furnace 301 through the reducing agent spraying device 304.

[0089] The reducing agent spraying device 304 includes a spraying tank, a spray gun, a pressure regulating device and a spraying pipeline.

[0090] The electric smelting furnace 301 produces coal gas as a by-product during the smelting process. After the coal gas is dedusted by the coal gas dust removal device 307, it is introduced into the coal gas mixing and regulating device 400 through the coal gas pressure regulating device 308, mixed with the coal gas from the pyrolysis gasification furnace 102, and then sent to the rotary hearth furnace combustion system. It can also be directly supplied to the rotary hearth furnace combustion system separately.

[0091] Refer to Figure 2 As shown, this embodiment provides a low-carbon collaborative utilization method for multi-source solid waste and organic solid waste, and the low-carbon collaborative utilization device of this embodiment is used to perform the following steps:

[0092] S1, the organic solid waste and biomass are fed into the pyrolysis gasification furnace 102 after batching, mixing, adjusting the calorific value, and pre-treatment. The organic solid waste and biomass are pyrolyzed to generate coal gas, which is sent to the pre-reduction device 200 as fuel after passing through the coal gas temperature / composition regulating device 103 and the coal gas dust removal device 104. The biomass carbon after pyrolysis enters the batching device 201 as a reducing agent of the pre-reduction device 200;

[0093] S2, the metal-containing solid waste is fed into the annular pre-reduction furnace device 204 for reduction after batching, briquetting and drying. Iron is reduced to form pre-reduced metallized pellets. Low-melting-point metals such as zinc are reduced and volatilized into flue gas. The flue gas is discharged after passing through a settling chamber, a waste heat boiler and a dust collecting device. Low-melting-point metals such as zinc are collected as products during the flue gas cooling process. The annular pre-reduction furnace device 204 uses the coal gas from the pyrolysis gasification furnace 102 and the coal gas from the final reduction smelting device 300 as fuel;

[0094] S3, the metallized pellets produced by the pre-reduction device 200 enter the final reduction smelting device 300 through the hot charging system 305, and other metal materials can be added at the same time, and part of the reducing agent and flux can be added. The final reduction smelting device 300 adopts electric heating smelting, sprays part of the carbon powder as a reducing agent, and performs final reduction on the unreduced metal oxides. The coal gas produced by the final reduction smelting device 300 enters the pre-reduction device 200 as fuel through the coal gas mixing and regulating device 400.

[0095] The pyrolysis gasification furnace 102 uses air or oxygen for gasification, and adds some steam to adjust the gas composition and bring in some heat. The organic solid waste and biomass react with oxygen in the pyrolysis gasification furnace 102, and some combustion provides the heat required for pyrolysis. The gasification temperature is controlled at 500℃~800℃, and a certain amount of steam is introduced to bring in heat and adjust the gas composition. The calorific value of the gasified gas is controlled at 1500kcal / Nm 3 In the above, oxygen or air is provided with flow and pressure regulating devices, and the supply of oxygen and air is adjusted according to the ingredients and the temperature of the pyrolysis gasification furnace.

[0096] The pre-reduction temperature in the annular pre-reduction furnace device 204 is controlled at 1050°C to 1300°C, reducing part of the metal oxides in the dust to metals, and the low-melting-point elements enter the flue gas and are enriched and recovered in the flue gas treatment device 206.

[0097] The flue gas outlet temperature of the annular pre-reduction furnace device 204 is 1000℃~1250℃. After the waste heat recovery, steam is recovered. The flue gas passes through the settling chamber and the waste heat boiler and then enters the dust collector to collect the dust in the system. After the zinc in the flue gas enters the flue gas treatment system, it is oxidized into zinc oxide during the flue gas cooling process and is collected by the dust collection system together with the dust as a zinc oxide product. The dust-removed flue gas is discharged after passing through the induced draft fan and chimney.

[0098] The main raw material of the final reduction smelting device 300 is the pre-reduction raw material reduced by the annular pre-reduction furnace device 204, which is added to the electric heating type smelting furnace 301 through the feeding device 303 under high temperature, which significantly reduces the energy consumption of the final reduction furnace. The electric heating type smelting furnace 301 adds a certain proportion of reducing agent and flux through the batching system 302, and adds different proportions of scrap steel according to the demand for molten iron. The added furnace charge is heated, melted, and reduced in the electric heating type smelting furnace 301. The reduction smelting temperature is controlled at 1500℃~2000℃, and the pre-reduction raw material is reduced and smelted into molten iron. The electric heating type smelting furnace 301 can use block or powder reducing agent, and carbon powder and other powder reducing agents can be sprayed into the final reduction furnace through the reducing agent spraying device 304.

[0099] The electric smelting furnace 301 produces coal gas as a by-product during the smelting process. The coal gas is sent to the annular pre-reduction furnace device 204 as fuel through the coal gas mixing and regulating device 400. At the same time, the pressure inside the electric smelting furnace 301 is controlled by the coal gas mixing and regulating device 400 to ensure a slight negative pressure inside the electric smelting furnace 301 to prevent dust and coal gas from escaping.

[0100] In summary, the low-carbon coordinated utilization device and method of multi-source solid waste and organic solid waste proposed in the present invention can coordinately dispose of organic solid waste, iron-containing and zinc-containing solid waste and other resources for resource utilization. After pretreatment, the organic solid waste enters the pyrolysis gasification device, where it is pyrolyzed to produce pyrolysis gas and pyrolysis gasification carbon. After pretreatment, wastes such as iron-containing dust and mud are added with a binder and pyrolysis gasification carbon or supplemented with a certain reducing agent to be pressed into balls, and then enter the pre-reduction device for pre-reduction after drying. The pre-reduction furnace uses pyrolysis gas as fuel, and the reduced pre-reduction raw materials are pressed into blocks or cooling devices or directly hot-charged into the final reduction smelting furnace, reduced and smelted into molten iron and slag. The flue gas of the pre-reduction furnace is recovered through waste heat and collected through a dust collector to obtain a zinc oxide-rich product. The by-product gas of the final reduction melting device and the pyrolysis gas are used together as fuel for the pre-reduction furnace to provide heat for the pre-reduction furnace process. The present invention can coordinate the treatment and source utilization of iron-containing solid waste and organic solid waste to produce molten iron and zinc oxide-rich products. The pyrolysis gasification furnace is used to generate gas, and the metal solid waste is used as the raw material for pre-reduction. The final reduction is then carried out in an electric heating smelting furnace to melt the metallized pellets into molten iron products. This not only solves the problem of harmful elements in the smelting process, provides a comprehensive solution to smelting dust and mud, but also reduces the carbon used for combustion and heating, and reduces carbon emissions from molten iron. It also solves the problem of the source of coal gas in the treatment of dust and mud in short-process steel mills and the treatment of iron- and zinc-containing tailings and tailings in non-ferrous smelting.

[0101] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present invention, and are not intended to limit the present invention. As long as they are within the spirit of the present invention, any changes or modifications to the above embodiments will fall within the scope of the claims of the present invention.

Claims

1. A low-carbon synergistic utilization device for multi-source solid waste and organic solid waste, characterized in that: include: Pyrolysis gasification device, used for pyrolysis of biomass and organic solid waste; Pre-reduction device, used for pre-treatment of dust and mud; A final reduction smelting device, used for smelting the pre-reduction raw materials reduced by the pre-reduction device; The coal gas mixing and regulating device is connected to the pyrolysis gasification device and the final reduction smelting device, and is used to send the mixed coal gas to the pre-reduction device.

2. The low-carbon synergistic utilization device of multi-source solid waste and organic solid waste according to claim 1, characterized in that: The pyrolysis gasification device adopts a fixed bed or fluidized bed form, and comprises a batching and feeding device, a pyrolysis gasification furnace, a coal gas temperature / component regulating device and a coal gas dust removal device which are connected in sequence.

3. The low-carbon synergistic utilization device of multi-source solid waste and organic solid waste according to claim 2, characterized in that: The pre-reduction device is in the form of an annular pre-reduction furnace, including a batching device, a ball pressing device, a drying device, an annular pre-reduction furnace device and a discharge device which are connected in sequence; The batching device is communicated with the outlet of the pyrolysis gasification furnace.

4. The low-carbon synergistic utilization device of multi-source solid waste and organic solid waste according to claim 3 is characterized by: The annular pre-reduction furnace device is also connected to a flue gas treatment device; The smoke treatment device is provided with a smoke exhaust fan.

5. The low-carbon synergistic utilization device of multi-source solid waste and organic solid waste according to claim 3, characterized in that: The final reduction smelting device adopts an electric heating smelting furnace; The inlet of the electric heating type melting furnace is connected in sequence with a batching system and a feeding device; and It is also equipped with original agent spraying device and hot charging system; The outlet of the electric smelting furnace is provided with an iron / slag discharging device; The electric heating melting furnace is also provided with a gas dust removal device; The coal gas dust removal device is provided with a pressure regulating device; The shrink-fit system is communicated with the discharge device.

6. A low-carbon synergistic utilization method of multi-source solid waste and organic solid waste, characterized in that: The low-carbon synergistic utilization device for multi-source solid waste and organic solid waste as claimed in any one of claims 1 to 5 is used to perform the following steps: S1, organic solid waste and biomass are transported to the batching and feeding device, and the composition and calorific value are analyzed to determine the proportion of various raw materials. After the gasification method is selected according to the calorific value and composition, the raw materials are transported to the pyrolysis gasification furnace; S2, the organic solid waste and biomass undergo pyrolysis reaction with oxygen in the pyrolysis gasification furnace to produce pyrolysis gas and pyrolysis gasified carbon; S3, the waste containing iron dust and mud is pre-treated, and then a binder and pyrolysis gasified carbon or a set amount of reducing agent is added, and the waste is pressed into balls by the ball pressing device, and then dried by the drying device and then enters the annular pre-reduction furnace device for pre-reduction; S4, the annular pre-reduction furnace device uses pyrolysis gas as fuel, and the reduced pre-reduction raw materials are briquette or cooled or directly hot-charged into the electric heating smelting furnace for reduction and smelting into molten iron and slag; S5, the flue gas of the annular pre-reduction furnace is recovered through waste heat and collected by a dust collector to obtain a zinc oxide-rich product; S6, the byproduct gas of the electric smelting furnace and the pyrolysis gas are used together as fuel for the annular pre-reduction furnace to provide heat for the process of the annular pre-reduction furnace.

7. The low-carbon synergistic utilization method of multi-source solid waste and organic solid waste according to claim 6, characterized in that: In the step S2, the pyrolysis gasification furnace uses pure oxygen or air for gasification; The gasification temperature is 500~800℃; The calorific value of gasification gas is 1500kcal / Nm 3 above.

8. The low-carbon synergistic utilization method of multi-source solid waste and organic solid waste according to claim 7, characterized in that: The coal gas temperature / composition regulating device is arranged at the outlet of the pyrolysis gasification furnace, and the coal gas temperature / composition is regulated by introducing steam or oxygen.

9. The low-carbon synergistic utilization method of multi-source solid waste and organic solid waste according to claim 6, characterized in that: In step S4, the pre-reduction temperature of the annular pre-reduction furnace device is between 1050°C and 1300°C, and the discharge temperature is above 1000°C.

10. The low-carbon synergistic utilization method of multi-source solid waste and organic solid waste according to claim 6, characterized in that: In the step S4, the reduction smelting temperature of the electric smelting furnace is between 1500°C and 2000°C.

11. The low-carbon synergistic utilization method of multi-source solid waste and organic solid waste according to claim 6, characterized in that: The step S5 specifically includes: The flue gas discharged from the annular pre-reduction furnace enters the settling chamber, the waste heat boiler and the heat exchanger in sequence for cooling, and enters the dust collector to collect the zinc dust in the flue gas. The flue gas after dust removal is finally extracted through the exhaust fan.

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