CN207026092U

CN207026092U - The system for handling house refuse

Info

Publication number: CN207026092U
Application number: CN201720255156.3U
Authority: CN
Inventors: 任浩华; 张安强; 刘璐; 赵月晶; 周方远; 肖磊; 吴道洪
Original assignee: Shenwu Technology Group Corp Co Ltd
Current assignee: Shenwu Technology Group Corp Co Ltd
Priority date: 2017-03-15
Filing date: 2017-03-15
Publication date: 2018-02-23
Anticipated expiration: 2027-03-15

Abstract

The utility model discloses a kind of system for handling house refuse, the system includes：Pretreatment unit, there is house refuse entrance, organic waste outlet and inorganic refuse outlet；Pyrolysis installation, there is organic waste entrance, high temperature pyrolysis of oil and gas outlet, pyrolytic carbon outlet and pyrolysis offgas outlet；Collecting carbonic anhydride unit, there is gas inlet and carbon dioxide gas outlet；First energy-conservation deacidifying device, carbon dioxide gas outlet after oil gas vent and preheating is pyrolyzed after there is high temperature pyrolysis of oil and gas entrance, carbon dioxide entrance, cooling depickling；Methanol synthesis unit, there is carbon dioxide entrance and methanol outlet after hydrogen inlet, preheating.The minimizing that can realize house refuse using the system is handled, while the CO by that will be pyrolyzed in tail gas₂Utilized as the raw material for preparing methanol, so as to reduce greenhouse gases CO while realizing that domestic garbage resource utilizes₂Discharge, especially suitable for Technique Popularizing and large-scale production.

Description

System for treating household garbage

Technical Field

The utility model belongs to solid waste resourceful treatment field particularly, the utility model relates to a system for handle domestic waste.

Background

China is facing double pressure of environment and energy, with the acceleration of economic and urbanization progress, energy consumption is huge in China, and 2/3 faces the dilemma of refuse city in large cities. The domestic garbage is changed into available resources by technical means, and the crisis of energy and environment in China can be relieved to a certain extent. The household garbage pyrolysis technology is more and more favored by people due to the advantages of high resource utilization rate and small environmental pollution. The main products of pyrolysis are the following: first, pyrolysis oil; a part of pyrolysis oil can be used as fuel oil through refining; secondly, pyrolysis gas; the pyrolysis gas comprises some low molecular hydrocarbons, such as hydrogen, methane, carbon monoxide and the like, and can be used as fuel gas; thirdly, pyrolyzing carbon; most of pyrolytic carbon exists in the form of carbon black, but toxic and harmful substances such as heavy metals exist, the calorific value is low, the market sales is poor, if the pyrolytic carbon is used as solid fuel, the combustion effect is poor, a large amount of secondary pollutants can be generated in the combustion process, the environmental protection benefit is poor, and therefore most of pyrolytic carbon can only be finally used as pyrolytic residues for landfill treatment, a large amount of land resources are occupied, and the energy waste is caused.

Currently, with the development of economy, carbon emission reduction has become a subject of concern. As a household garbage pyrolysis treatment technology, the method realizes the recycling of household garbage and simultaneously generates a large amount of CO₂，CO₂Is one of the main components of greenhouse gases causing global warming, contributes 55 percent to the greenhouse effect, and is a precious resource. At present, CO₂The method is widely applied to the fields of food preservation, oil extraction industry, gas shielded welding, chemical synthesis and the like, and obtains good economic benefit. The annual consumption for production is however only a proportion of the CO emitted₂A small part of the total yield, a large amount of CO₂Cannot be fully utilized and is discharged into the atmosphere, thus intensifying the greenhouse effect and being a key factor for restricting the sustainable development of enterprises.

Therefore, the existing technology for disposing the household garbage needs to be further improved.

SUMMERY OF THE UTILITY MODEL

The present invention aims at solving at least one of the technical problems in the related art to a certain extent. Therefore, the utility model discloses an aim at provides a system for handle domestic waste. The system can realize the reduction treatment of the household garbage, and simultaneously, CO in the pyrolysis tail gas is treated₂Is used as a raw material for preparing methanol, thereby reducing greenhouse gas CO while realizing the resource utilization of household garbage₂Discharging, and is particularly suitable for technical popularization and large-scale production.

In an aspect of the utility model, the utility model provides a system for handle domestic waste, according to the utility model discloses an embodiment, this system includes:

a pre-treatment unit having a household waste inlet, an organic waste outlet and an inorganic waste outlet;

the pyrolysis device is provided with an organic garbage inlet, a high-temperature pyrolysis oil gas outlet, a pyrolysis carbon outlet and a pyrolysis tail gas outlet, and the organic garbage inlet is connected with the organic garbage outlet;

the carbon dioxide capturing unit is provided with a tail gas inlet and a carbon dioxide gas outlet, and the tail gas inlet is connected with the pyrolysis tail gas outlet;

the first energy-saving deacidification device is provided with a high-temperature pyrolysis oil gas inlet, a carbon dioxide gas inlet, a cooled deacidified pyrolysis oil gas outlet and a preheated carbon dioxide gas outlet, wherein the carbon dioxide gas inlet is connected with the carbon dioxide gas outlet, and the high-temperature pyrolysis oil gas inlet is connected with the high-temperature pyrolysis oil gas outlet;

the methanol synthesis unit is provided with a hydrogen inlet, a preheated carbon dioxide gas inlet and a methanol outlet, and the preheated carbon dioxide gas inlet is connected with the preheated carbon dioxide gas outlet.

According to the system for treating the household garbage, the household garbage is pretreated and then supplied to the pyrolysis device for pyrolysis treatment, so that high-temperature pyrolysis oil gas, pyrolysis carbon and pyrolysis tail gas are obtained; the pyrolysis tail gas enters the carbon dioxide capture unit to be captured by the carbon dioxide, and then the captured carbon dioxide gas is supplied to the first energy-saving deacidification device to be subjected to heat exchange and deacidification treatment, so that the carbon dioxide gas is preheated, and the preheated carbon dioxide gas enters the methanol synthesis unit to be used for synthesizing methanol. Therefore, the system extracts carbon dioxide from the pyrolysis tail gas obtained by pyrolyzing the household garbage as the raw material for synthesizing the methanol, realizes resource utilization of the household garbage, obviously reduces the emission of carbon dioxide gas, has obvious economic benefit and environmental benefit, and is particularly suitable for technical popularization and large-scale production.

Optionally, the system for treating domestic garbage further comprises: the pyrolysis oil gas purification unit is provided with a cooling deacidification post-pyrolysis oil gas inlet, a pyrolysis oil outlet and a pyrolysis gas outlet, and the cooling deacidification post-pyrolysis oil gas inlet is connected with the cooling deacidification post-pyrolysis oil gas outlet; the hydrogen capture unit is provided with a pyrolysis gas inlet, a hydrogen outlet and a combustible gas outlet, the pyrolysis gas inlet is connected with the pyrolysis gas outlet, and the hydrogen outlet is connected with the hydrogen inlet; the power generation unit is provided with a fuel inlet, a water vapor outlet and a combustion tail gas outlet, the fuel inlet is respectively connected with the pyrolysis oil outlet and the combustible gas outlet, and the combustion tail gas outlet is connected with the tail gas inlet. Therefore, the combustible gas separated from the pyrolysis oil and the pyrolysis gas obtained by separating the pyrolysis oil gas obtained by pyrolyzing the household garbage can be used as fuel for power generation, so that the resource utilization rate of the household garbage is further improved.

Optionally, the system for treating domestic garbage further comprises: the crushing device is provided with a pyrolytic carbon inlet and a pyrolytic carbon particle outlet, and the pyrolytic carbon inlet is connected with the pyrolytic carbon outlet; the gasification device is provided with a pyrolytic carbon particle inlet, a water vapor inlet, a gasified gas outlet and a gasified residue outlet, the pyrolytic carbon particle inlet is connected with the pyrolytic carbon particle outlet, and the water vapor inlet is connected with the water vapor outlet; the second energy-saving deacidification device is provided with a gasified gas inlet and a gasified gas outlet after temperature reduction and deacidification, and the gasified gas inlet is connected with the gasified gas outlet; gasified gas purification unit, gasified gas purification unit has cooling deacidification back gasified gas entry and purification gasified gas export, cooling deacidification back gasified gas entry with cooling deacidification back gasified gas export links to each other, purification gasified gas export with the pyrolysis device links to each other. From this, can obtain the pyrolytic carbon granule through breaker with the pyrolytic carbon breakage, and then supply the pyrolytic carbon granule to gasification equipment, and utilize the vapor that obtains in the power generation unit with the pyrolytic carbon granule gasification for the gasification gas that uses carbon monoxide and hydrogen as the principal ingredients, the gasification gas gets into the energy-conserving deacidification device of second and passes through the heat transfer with the combustion-supporting gas after the deacidification treatment, the cooling deacidification that obtains back gasification gas and the combustion-supporting gas after preheating, the cooling deacidification back gasification gas gets into and carries out purification treatment in the gasification gas purification unit, obtain the purification gasification gas, follow-up fuel that can be used for among the pyrolysis equipment uses, from this, realized the utilization of resources to low heat value pyrolytic carbon.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural view of a system for treating domestic garbage according to an embodiment of the present invention;

fig. 2 is a schematic structural view of a system for treating domestic garbage according to still another embodiment of the present invention;

fig. 3 is a schematic structural view of a system for treating domestic waste according to yet another embodiment of the present invention;

fig. 4 is a flow chart illustrating a method for processing domestic garbage according to an embodiment of the present invention;

fig. 5 is a flow chart illustrating a method for processing domestic garbage according to a system for processing domestic garbage according to still another embodiment of the present invention;

fig. 6 is a flow chart illustrating a method for processing domestic garbage according to a system for processing domestic garbage according to another embodiment of the present invention;

fig. 7 is a schematic structural view of a system for treating domestic waste according to another embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In an aspect of the present invention, the utility model provides a system for handle domestic waste, according to the utility model discloses an embodiment, refer to fig. 1, this system includes: a pretreatment unit 100, a pyrolysis apparatus 200, a carbon dioxide capture unit 300, a first energy-saving deacidification apparatus 400, and a methanol synthesis unit 500.

According to the utility model discloses an embodiment, preprocessing unit 100 has domestic waste entry 101, organic rubbish export 102 and inorganic rubbish export 103, and is suitable for carrying out the preliminary treatment with domestic waste to obtain organic rubbish and inorganic rubbish. Specifically, by pretreating the household garbage, large inorganic matters, metals and other inorganic garbage in the household garbage can be removed, and organic garbage required by next pyrolysis can be obtained. It should be noted that the pretreatment unit is not particularly limited, and those skilled in the art can select the pretreatment unit according to actual needs, and for example, the pretreatment unit may include a bag breaker, a roller screen classifier, a sorter and a crusher connected in sequence. Specifically, inorganic substances such as metal, glass, bricks and the like in the household garbage can be removed through the bag breaking mechanism, the rolling screen mechanism and the sorting mechanism, and then the household garbage is broken through the breaking mechanism. According to the utility model discloses a concrete embodiment, after above-mentioned pretreatment unit handles, can obtain the organic rubbish that the particle diameter that satisfies the requirements of revolving bed pyrolysis furnace pan feeding is less than 20mm, and the moisture content of organic rubbish is 20 wt% -60 wt%.

According to the utility model discloses an embodiment, pyrolysis device 200 has organic rubbish entry 201, high temperature pyrolysis oil gas export 202, pyrolytic carbon export 203 and pyrolysis tail gas export 204, and organic rubbish entry 201 links to each other with organic rubbish export 102, and is suitable for and carries out pyrolysis treatment with organic rubbish to obtain high temperature pyrolysis oil gas, pyrolytic carbon and pyrolysis tail gas. It should be noted that the pyrolysis device is not particularly limited, and those skilled in the art can select the pyrolysis device according to actual needs, for example, the pyrolysis device can be a regenerative rotary bed pyrolysis furnace without heat carrier. Specifically, it should be noted that the pyrolysis apparatus is not particularly limited, and those skilled in the art can select the pyrolysis apparatus according to actual needs, for example, the pyrolysis apparatus can be a regenerative rotary bed pyrolysis furnace without heat carrier. Specifically, the obtained organic garbage is uniformly conveyed to a rotary bed pyrolysis furnace, the paving thickness is 50-250mm, the temperature is raised in the furnace in stages, the drying, pyrolysis and activation reactions are completed, and the time of one circle of rotation of the rotary bed pyrolysis furnace is 1 h. The rotary bed pyrolysis furnace comprises a rotary bed pyrolysis chamber, an annular furnace bottom, heat accumulating type gas radiation pipe burners respectively positioned on the annular furnace bottom and below the annular furnace bottom, and mechanisms for distributing, discharging and the like, wherein the heat accumulating type gas radiation pipe burners are arranged on the annular furnace wall to provide heat required by garbage pyrolysis in a heat radiation mode. The revolving bed pyrolysis furnace has set gradually the drying zone along pivoted direction, pyrolytic reaction district, pyrolytic reaction two district and pyrolytic reaction are three, pending organic rubbish gets into the revolving bed pyrolysis furnace from the drying zone, furnace roof in each region of revolving bed pyrolysis furnace all is provided with the pyrolysis oil gas export, be used for collecting pyrolysis oil gas, be provided with discharging device in the three regional terminal pyrolysis charcoal exit of pyrolytic reaction, be used for collecting the pyrolysis charcoal, in addition, be heated evenly for making pending organic rubbish, the perforated plate can be chooseed for use to the stove bottom flitch.

According to the utility model discloses an embodiment, carbon dioxide entrapment unit 300 has tail gas entry 301 and carbon dioxide gas outlet 302, and tail gas entry 301 links to each other with pyrolysis tail gas outlet 204, and is suitable for to handle pyrolysis tail gas to obtain carbon dioxide gas. The carbon dioxide capture unit is not particularly limited, and may be selected by those skilled in the art according to actual needs, and may include, for example, an absorption column, a rich liquid pump, a desorption column, a reboiler, a gas-liquid separator, a lean liquid pump, and a lean liquid cooler, which are connected in series. Specifically, pyrolysis tail gas from a pyrolysis device is pressurized by a fan and fed into an absorption tower, and is in countercurrent contact with an absorbent in the absorption tower, so that CO in the pyrolysis tail gas₂Absorbed by the absorbent to become rich liquid, the rich liquid is pumped into the desorption tower to generate CO through desorption₂Mixed gas of gas, steam and mist and barren solution, desorbed CO₂Cooling by a cooler to obtain water and foam, introducing the cooled mixed gas into a gas-liquid separator, and removing the water and foam to obtain CO₂A gas. Wherein,the specific type of the absorbent is not particularly limited, and can be selected by those skilled in the art according to actual needs, and can be, for example, an alcohol amine solution.

According to the utility model discloses an embodiment, first energy-conserving deacidification device 400 has pyrolysis oil gas entry 401, carbon dioxide gas entry 402, cooling deacidification back pyrolysis oil gas export 403 and preheating back carbon dioxide gas export 404, carbon dioxide gas entry 402 links to each other with carbon dioxide gas export 302, pyrolysis oil gas entry 401 links to each other with pyrolysis oil gas export 202, and be suitable for and carry out heat transfer and deacidification with carbon dioxide gas and pyrolysis oil gas, so that obtain preheating back carbon dioxide gas and cooling deacidification back pyrolysis oil gas. It should be noted that the first energy-saving deacidification device is not particularly limited, and may be selected by those skilled in the art according to actual needs, and may include, for example, an inert gas pipeline, a pyrolysis gas pipeline, two four-way reversing valves, and a deacidification-heat accumulation complex, and the deacidification mode in this step may be any method capable of removing acidic substances in high-temperature pyrolysis oil gas in the prior art, and may be selected by those skilled in the art according to actual needs. Specifically, the high-temperature pyrolysis oil gas from the pyrolysis device enters a first energy-saving deacidification device through a pipeline to complete waste heat recovery and deacidification, the temperature of the high-temperature pyrolysis oil gas is reduced to 200 ℃, and the concentration of the acid gas is reduced to 0.02%. The first energy-saving deacidification device can be used for collecting high-purity CO₂Preheating gas, preheated CO₂The temperature of the gas can reach 100-500 ℃.

According to the utility model discloses an embodiment, methyl alcohol synthetic unit 500 has hydrogen inlet 501, preheats back carbon dioxide gas entry 502 and methyl alcohol export 503, preheats back carbon dioxide gas entry 502 and links to each other with preheating back carbon dioxide gas export 404, and is suitable for to handle preheating back carbon dioxide gas and hydrogen to obtain methyl alcohol. It should be noted that the methanol synthesis unit is not particularly limited, and those skilled in the art can select the unit according to actual needs, and for example, a methanol synthesis unit and a methanol rectification unit can be included. Wherein the methanol synthesis device and the methanol rectification device are combinedWithout particular limitation, those skilled in the art can select the methanol synthesis apparatus according to actual needs, for example, the methanol synthesis apparatus may include a gasification gas reformer and a methanol synthesis column, and the methanol rectification apparatus may adopt a double column flow, and consists of a pre-column and a main column. In particular, preheated CO₂The gas and the hydrogen are compressed to 5-7MPa by a synthesis gas compressor and then enter a methanol synthesis device together, the methanol synthesis adopts one or more of oxides of copper, zinc and aluminum as a catalyst, the reaction pressure is 6-9MPa, the reaction temperature is 200-300 ℃, and the synthesized crude methanol is rectified by a methanol rectifying tower to prepare the methanol.

According to the embodiment of the present invention, referring to fig. 2, the system for processing domestic garbage further comprises: a pyrolysis oil gas purification unit 600, a hydrogen capture unit 700, and a power generation unit 800.

According to the embodiment of the utility model, pyrolysis oil gas purification unit 600 has pyrolysis oil gas entry 601, pyrolysis oil export 602 and pyrolysis gas export 603 after cooling deacidification, and pyrolysis oil gas entry 601 links to each other with pyrolysis oil gas export 403 after cooling deacidification, and is suitable for and carries out purification treatment with pyrolysis oil gas after the cooling deacidification that first energy-conserving deacidification device obtained toSo as to obtain pyrolysis oil and pyrolysis gas. It should be noted that the pyrolysis oil gas purification unit is not particularly limited, and may be selected by those skilled in the art according to actual needs, and may include, for example, a dust removal tower, a primary cooler, an electrical tar precipitator, and a dry desulfurization tower, which are connected in sequence. According to the utility model discloses a concrete embodiment, pyrolysis oil gas after the cooling deacidification that comes from first energy-conserving deacidification device gets into pyrolysis oil gas purification unit and can realize dust removal, desulfurization and the denitration etc. to pyrolysis oil gas after the cooling deacidification for H₂The content of S is not more than 0.01g/Nm³The content of dust is not more than 50mg/Nm³The content of benzene is not more than 20mg/Nm³The content of HCl is not more than 10mg/Nm³. Specifically, after temperature reduction and deacidification, spraying chilling circulating water on pyrolysis oil gas for temperature reduction, separating the pyrolysis oil gas into pyrolysis gas to be purified and pyrolysis oil water, and conveying the pyrolysis oil water to an oil-water separation tank through a pipeline to separate the pyrolysis oil water into pyrolysis oil and wastewater; the method comprises the following steps that the pyrolysis gas to be purified is dedusted through a wet dedusting tower, the dust in the pyrolysis gas is removed and then enters a transverse pipe primary cooler, the primary cooler cools the dedusted pyrolysis gas to about 21 ℃ through two sections of cooling water of circulating water at 32 ℃ and cooling water at 16 ℃, the pyrolysis gas discharged from the lower portion of the primary cooler enters two electric tar trappers which are connected in parallel and operate simultaneously, tar entrained in the pyrolysis gas is removed, the tar and the pyrolysis gas to be desulfurized and denitrated are obtained, and finally the pyrolysis gas is sent to a desulfurization and denitrification tower through a Roots blower to complete desulfurization and denitrification, so that the pure pyrolysis gas is obtained.

According to the utility model discloses an embodiment, hydrogen capture unit 700 has pyrolysis gas entry 701, hydrogen export 702 and combustible gas export 703, and pyrolysis gas entry 701 links to each other with pyrolysis gas export 603, and hydrogen export 702 links to each other with hydrogen entry 501, and is suitable for and handles pyrolysis gas to obtain hydrogen and combustible gas, and supply hydrogen to the methanol synthesis unit. The hydrogen trapping unit is not particularly limited, and may be selected by those skilled in the art according to actual needs, and may be, for example, a hydrogen adsorption column. Specifically, the hydrogen pressure swing adsorption tower purifies hydrogen by utilizing the characteristic that an adsorbent has different adsorption capacities for adsorbates under different partial pressures and has selective adsorption on each component of a separated gas mixture under certain adsorption pressure. The pressure swing adsorption tower is formed by connecting 4 adsorption beds in parallel, the adsorption pressure range is 1-3 MPa, the adsorbent adopts activated carbon, the hydrogen recovery rate is more than 92%, and the collected hydrogen can be sent to a methanol synthesis unit to react with preheated carbon dioxide gas to prepare methanol, so that the raw material cost of the whole system can be obviously reduced, and the economic benefit of the whole system is improved.

According to the utility model discloses an embodiment, power generation unit 800 has fuel entry 801, steam outlet 802 and burning tail gas export 803, and fuel entry 801 links to each other with pyrolysis oil export 602 and combustible gas export 703 respectively, and burning tail gas export 803 links to each other with tail gas entry 301, and is suitable for the pyrolysis oil that obtains pyrolysis oil gas purification unit and the combustible gas burning electricity generation that the hydrogen entrapment unit obtained to obtain steam and burning tail gas, and will burn tail gas supply to carbon dioxide entrapment unit. Specifically, the pyrolysis oil and the combustible gas can be supplied to a waste heat boiler of the power generation unit, superheated steam is generated in the waste heat boiler through heat exchange with water or combustion, the superheated steam enters a steam turbine to drive a generator to generate power, the generated electric energy is merged into a power grid, and combustion tail gas generated by the power generation unit can enter a carbon dioxide capture unit to capture and utilize carbon dioxide.

According to the embodiment of the present invention, referring to fig. 3, the system for processing domestic garbage further comprises: a crushing device 900, a gasification device 1000, a second energy-saving deacidification device 1100 and a gasification gas purification unit 1200.

According to the utility model discloses an embodiment, breaker 900 has pyrolytic carbon entry 901 and pyrolytic carbon granule export 902, and pyrolytic carbon entry 901 links to each other with pyrolytic carbon export 203, and is suitable for to carry out broken handle with the pyrolytic carbon to obtain the pyrolytic carbon granule. Specifically, the garbage carbon obtained by the pyrolysis device is crushed by a crushing device to obtain garbage carbon particles with the particle size not larger than 10 mm. The inventors found that by crushing the pyrolytic char to the particle size in advance before subjecting the pyrolytic char to the gasification treatment, it is possible to significantly improve the efficiency of the gasification treatment and reduce the energy consumption of the gasification treatment.

According to the utility model discloses an embodiment, gasification equipment 1000 has pyrolytic carbon particle entry 1001, steam inlet 1002, gasification gas export 1003 and gasification residue export 1004, and pyrolytic carbon particle entry 1001 links to each other with pyrolytic carbon particle export 902, and steam inlet 1002 links to each other with steam export 802, and is suitable for the steam that obtains pyrolytic carbon particle and power generation unit to carry out gasification treatment to obtain gasification gas and gasification residue. The gasification apparatus is not particularly limited, and may be selected by those skilled in the art according to the actual needs, and may be, for example, a circulating fluidized bed gasification furnace. Specifically, pyrolytic carbon particles crushed to the particle size of not more than 10mm are used as gasification raw materials and conveyed to a circulating fluidized bed gasification furnace through pressure equipment and a pipeline, water vapor and the pyrolytic carbon particles jointly enter the circulating fluidized bed gasification furnace for gasification, the gasification temperature is about 1000 ℃, gasified gas is obtained, and gasification residues can be used as building materials or landfill treatment due to low utilization value.

According to the utility model discloses an embodiment, the energy-conserving deacidification device of second 1100 has the gasified gas entry 1101 and the gaseous gas export 1102 after cooling and deacidifying, and the gasified gas entry 1101 links to each other with the gasified gas export 1003, and is suitable for carrying out heat transfer and deacidification with the gasified gas and handles to obtain the gasified gas after cooling and deacidifying. It should be noted that the second energy-saving deacidification apparatus may be configured in the same manner as the first energy-saving deacidification apparatus described above. Specifically, the gasified gas from the gasification device enters a second energy-saving deacidification device through a pipeline to complete waste heat recovery and deacidification, so as to obtain the gasified gas after temperature reduction and deacidification, the temperature of the gasified gas after temperature reduction and deacidification is reduced to 350 ℃, and the concentration of the acid gas is reduced to 0.02-0.05%.

According to the embodiment of the utility model, gasified gas purification unit 1200 has cooling deacidification back gasified gas entry 1201 and purification gasified gas export 1202, cooling deacidification back gasified gas entry 1201 links to each other with cooling deacidification back gasified gas export 1102, and purification gasified gas export 1202 links to each other with pyrolysis device 200, and is suitable for to carry out purification treatment with cooling deacidification back gasified gas toPurified gasification gas is obtained and returned to the pyrolysis device. It should be noted that the gasification gas purification unit is not particularly limited, and may be selected by those skilled in the art according to actual needs, and may include, for example, a dust removal tower, a primary cooler, and a dry desulfurization tower connected in series. The cooled deacidified gasified gas from the second energy-saving deacidification device enters the gasified gas purification unit to realize dedusting, desulfurization, denitration and the like of the cooled deacidified gasified gas, so that H in the gasified gas is treated₂The content of S is not more than 0.01g/Nm³The content of dust is not more than 50mg/Nm³The content of benzene is not more than 20mg/Nm³The content of HCl is not more than 10mg/Nm³. After temperature reduction and deacidification, the gasified gas is sprayed by chilling circulating water to be separated into gasified gas to be purified and tar, and the tar is conveyed to an oil-water separation tank through a pipeline to be separated into tar and wastewater; the method comprises the following steps that the gasified gas to be purified is dedusted through a wet dedusting tower, the dedusted gasified gas enters a transverse pipe primary cooler after being dedusted, the primary cooler cools the dedusted gasified gas to about 21 ℃ by using two sections of cooling water of circulating water at 32 ℃ and cooling water at 16 ℃, the gasified gas discharged from the lower part of the primary cooler enters two electric tar trappers which are connected in parallel and operate simultaneously, tar entrained in the gasified gas is removed, the tar and the gasified gas to be desulfurized and denitrated are obtained, and finally the gasified gas is sent to a desulfurization and denitrification tower by a roots blower to complete desulfurization and denitrification, so that pure gasified gas is obtained.

As mentioned above, the system for treating domestic garbage provided by the utility model has at least one of the following advantages:

according to the system for treating the household garbage, the rotary bed pyrolysis furnace is used as equipment for preparing oil, gas and carbon by pyrolyzing the organic garbage, drying and pyrolysis processes are completed in the same furnace, the flow is short, the energy utilization rate is high, meanwhile, the system is easy to amplify, and large-scale production is realized;

according to the system for treating the household garbage, the high-temperature pyrolysis oil gas and the gasification gas respectively and independently pass through the energy-saving deacidification device to realize waste heat recovery and acid gas removal, so that the energy utilization efficiency is improved, and the corrosion of the acid gas to equipment can be reduced;

according to the system for treating the household garbage, the pyrolytic carbon is used as a gasification raw material, the water vapor generated by the power generation unit is used as a gasification agent, and the circulating fluidized bed is used for gasifying the pyrolytic carbon, so that the problems of low thermal value of the pyrolytic carbon, poor market sales and poor economic benefit are solved;

according to the utility model discloses system for handle domestic waste, through adopting the high-purity H of entrapment in the pyrolysis gas₂And captured high purity CO₂The methanol is used as a raw material to prepare the methanol, so that the problem of high carbon emission in the process of garbage treatment is solved;

according to the utility model discloses system for handle domestic waste, CO₂The recovery rate can reach more than 90 percent, the purity can reach more than 98 percent, and CO is obtained by mixing₂Preheating to 100-₂Large discharge amount, low thermal value of the pyrolytic carbon, unsmooth market sale, poor economic benefit and low resource utilization rate.

For convenience of understanding, the method for processing domestic garbage implemented by the system for processing domestic garbage according to the embodiment of the present invention is described in detail with reference to fig. 4 to 6, and according to the embodiment of the present invention, the method includes:

s100: supplying the domestic garbage to a pretreatment unit for pretreatment

In this step, the domestic waste is fed to a pretreatment unit for pretreatment to obtain organic waste and inorganic waste. Specifically, by pretreating the household garbage, large inorganic matters, metals and other inorganic garbage in the household garbage can be removed, and organic garbage required by next pyrolysis can be obtained. It should be noted that the pretreatment unit is not particularly limited, and those skilled in the art can select the pretreatment unit according to actual needs, and for example, the pretreatment unit may include a bag breaker, a roller screen classifier, a sorter and a crusher connected in sequence. Specifically, inorganic substances such as metal, glass, bricks and the like in the household garbage can be removed through the bag breaking mechanism, the rolling screen mechanism and the sorting mechanism, and then the household garbage is broken through the breaking mechanism. According to the utility model discloses a concrete embodiment, after above-mentioned pretreatment unit handles, can obtain the organic rubbish that the particle diameter that satisfies the requirements of revolving bed pyrolysis furnace pan feeding is less than 20mm, and the moisture content of organic rubbish is 20 wt% -60 wt%.

S200: supplying the organic garbage to a pyrolysis device for pyrolysis treatment

In this step, the organic waste is supplied to a pyrolysis device for pyrolysis treatment, so as to obtain high-temperature pyrolysis oil gas, pyrolysis carbon and pyrolysis tail gas. It should be noted that the pyrolysis device is not particularly limited, and those skilled in the art can select the pyrolysis device according to actual needs, for example, the pyrolysis device can be a regenerative rotary bed pyrolysis furnace without heat carrier. Specifically, it should be noted that the pyrolysis apparatus is not particularly limited, and those skilled in the art can select the pyrolysis apparatus according to actual needs, for example, the pyrolysis apparatus can be a regenerative rotary bed pyrolysis furnace without heat carrier. Specifically, the obtained organic garbage is uniformly conveyed to a rotary bed pyrolysis furnace, the paving thickness is 50-250mm, the temperature is raised in the furnace in stages, the drying, pyrolysis and activation reactions are completed, and the time of one circle of rotation of the rotary bed pyrolysis furnace is 1 h. The rotary bed pyrolysis furnace comprises a rotary bed pyrolysis chamber, an annular furnace bottom, heat accumulating type gas radiation pipe burners respectively positioned on the annular furnace bottom and below the annular furnace bottom, and mechanisms for distributing, discharging and the like, wherein the heat accumulating type gas radiation pipe burners are arranged on the annular furnace wall to provide heat required by garbage pyrolysis in a heat radiation mode. The revolving bed pyrolysis furnace has set gradually the drying zone along pivoted direction, pyrolytic reaction district, pyrolytic reaction two district and pyrolytic reaction are three, pending organic rubbish gets into the revolving bed pyrolysis furnace from the drying zone, furnace roof in each region of revolving bed pyrolysis furnace all is provided with the pyrolysis oil gas export, be used for collecting pyrolysis oil gas, be provided with discharging device in the three regional terminal pyrolysis charcoal exit of pyrolytic reaction, be used for collecting the pyrolysis charcoal, in addition, be heated evenly for making pending organic rubbish, the perforated plate can be chooseed for use to the stove bottom flitch.

S300: supplying the pyrolysis off-gas to a carbon dioxide capture unit

In this step, the pyrolysis off-gas is supplied to a carbon dioxide capture unit so as to obtain carbon dioxide gas. The carbon dioxide capture unit is not particularly limited, and may be selected by those skilled in the art according to actual needs, and may include, for example, an absorption column, a rich liquid pump, a desorption column, a reboiler, a gas-liquid separator, a lean liquid pump, and a lean liquid cooler, which are connected in series. Specifically, pyrolysis tail gas from a pyrolysis device is pressurized by a fan and fed into an absorption tower, and is in countercurrent contact with an absorbent in the absorption tower, so that CO in the pyrolysis tail gas₂Absorbed by the absorbent to become rich liquid, the rich liquid is pumped into the desorption tower to generate CO through desorption₂Mixed gas of gas, steam and mist and barren solution, desorbed CO₂Cooling by a cooler to obtain water and foam, introducing the cooled mixed gas into a gas-liquid separator, and removing the water and foam to obtain CO₂A gas. The specific type of the absorbent is not particularly limited, and can be selected by those skilled in the art according to actual needs, such as alcohol amine solution.

S400: supplying carbon dioxide gas and high-temperature pyrolysis oil gas to a first energy-saving deacidification device for heat exchange and deacidification treatment

In the step, the carbon dioxide gas and the high-temperature pyrolysis oil gas are supplied to a first energy-saving deacidification device for heat exchange and deacidification treatment, so that the preheated carbon dioxide gas and the cooled and deacidified pyrolysis oil gas are obtained. It should be noted that the first energy-saving deacidification device is not particularly limited, and may be selected by those skilled in the art according to actual needs, and may include, for example, an inert gas pipeline, a pyrolysis gas pipeline, two four-way reversing valves, a deacidification-heat accumulation complex, and the deacidification mode in this step may be the mode in the prior art capable of removing acidity in high-temperature pyrolysis oil gasAny method of the substances can be selected by the person skilled in the art according to the actual requirements. Specifically, the high-temperature pyrolysis oil gas from the pyrolysis device enters a first energy-saving deacidification device through a pipeline to complete waste heat recovery and deacidification, the temperature of the high-temperature pyrolysis oil gas is reduced to 200 ℃, and the concentration of the acid gas is reduced to 0.02%. The first energy-saving deacidification device can be used for collecting high-purity CO₂Preheating gas, preheated CO₂The temperature of the gas can reach 100-500 ℃.

S500: supplying the preheated carbon dioxide gas and hydrogen gas to a methanol synthesis unit

In this step, the preheated carbon dioxide gas and hydrogen gas are supplied to a methanol synthesis unit to obtain methanol. It should be noted that the methanol synthesis unit is not particularly limited, and those skilled in the art can select the unit according to actual needs, and for example, a methanol synthesis unit and a methanol rectification unit can be included. The methanol synthesis device and the methanol rectification device are not particularly limited, and can be selected by those skilled in the art according to actual needs, for example, the methanol synthesis device can comprise a gasification gas converter and a methanol synthesis tower, and the methanol rectification device can adopt a double-tower process and consists of a pre-tower and a main tower. In particular, preheated CO₂The gas and the hydrogen are compressed to 5-7MPa by a synthesis gas compressor and then enter a methanol synthesis device together, the methanol synthesis adopts one or more of oxides of copper, zinc and aluminum as a catalyst, the reaction pressure is 6-9MPa, the reaction temperature is 200-300 ℃, and the synthesized crude methanol is rectified by a methanol rectifying tower to prepare the methanol.

According to the method for treating the household garbage, the household garbage is pretreated and then supplied to the pyrolysis device for pyrolysis treatment, so that high-temperature pyrolysis oil gas, pyrolysis carbon and pyrolysis tail gas are obtained; the pyrolysis tail gas enters the carbon dioxide capture unit to be captured by the carbon dioxide, and then the captured carbon dioxide gas is supplied to the first energy-saving deacidification device to be subjected to heat exchange and deacidification treatment, so that the carbon dioxide gas is preheated, and the preheated carbon dioxide gas enters the methanol synthesis unit to be used for synthesizing methanol. Therefore, the method extracts carbon dioxide from pyrolysis tail gas obtained by pyrolyzing the household garbage as a raw material for synthesizing the methanol, realizes resource utilization of the household garbage, obviously reduces the emission of carbon dioxide gas, has obvious economic benefit and environmental benefit, and is particularly suitable for technical popularization and large-scale production.

According to an embodiment of the present invention, referring to fig. 5, the method for disposing domestic garbage further includes:

s600: supplying the cooled and deacidified pyrolysis oil gas obtained in the step S400 to a pyrolysis oil gas purification unit for purification treatment

In the step, the cooled and deacidified pyrolysis oil gas obtained in the step S400 is supplied to a pyrolysis oil gas purification unit for purification treatment, so that pyrolysis oil and pyrolysis gas are obtained. It should be noted that the pyrolysis oil gas purification unit is not particularly limited, and may be selected by those skilled in the art according to actual needs, and may include, for example, a dust removal tower, a primary cooler, an electrical tar precipitator, and a dry desulfurization tower, which are connected in sequence. According to the utility model discloses a concrete embodiment, pyrolysis oil gas after the cooling deacidification that comes from first energy-conserving deacidification device gets into pyrolysis oil gas purification unit and can realize dust removal, desulfurization and the denitration etc. to pyrolysis oil gas after the cooling deacidification for H₂The content of S is not more than 0.01g/Nm³The content of dust is not more than 50mg/Nm³The content of benzene is not more than 20mg/Nm³The content of HCl is not more than 10mg/Nm³. Specifically, after temperature reduction and deacidification, spraying chilling circulating water on pyrolysis oil gas for temperature reduction, separating the pyrolysis oil gas into pyrolysis gas to be purified and pyrolysis oil water, and conveying the pyrolysis oil water to an oil-water separation tank through a pipeline to separate the pyrolysis oil water into pyrolysis oil and wastewater; dedusting the pyrolysis gas to be purified by a wet dedusting tower, removing dust in the pyrolysis gas, then feeding the pyrolysis gas into a transverse tube primary cooler, cooling the dedusted pyrolysis gas to about 21 ℃ by using two sections of cooling water of circulating water at 32 ℃ and cooling water at 16 ℃, feeding the pyrolysis gas discharged from the lower part of the primary cooler into two electric tar traps which are connected in parallel and operate simultaneously, and removing the entrained pyrolysis gas in the pyrolysis gasThe tar and the pyrolysis gas to be desulfurized and denitrated are obtained, and finally the pyrolysis gas is sent to the desulfurization and denitrating tower by the Roots blower to complete desulfurization and denitrating, so that pure pyrolysis gas is obtained.

S700: supplying the pyrolysis gas to a hydrogen capture unit

In this step, the pyrolysis gas is supplied to a hydrogen capture unit to obtain hydrogen and a combustible gas, and the hydrogen is supplied to a methanol synthesis unit in S500. The hydrogen trapping unit is not particularly limited, and may be selected by those skilled in the art according to actual needs, and may be, for example, a hydrogen adsorption column. Specifically, the hydrogen pressure swing adsorption tower purifies hydrogen by utilizing the characteristic that an adsorbent has different adsorption capacities for adsorbates under different partial pressures and has selective adsorption on each component of a separated gas mixture under certain adsorption pressure. The pressure swing adsorption tower is formed by connecting 4 adsorption beds in parallel, the adsorption pressure range is 1-3 MPa, the adsorbent adopts activated carbon, the hydrogen recovery rate is more than 92%, and the collected hydrogen can be sent to a methanol synthesis unit to react with preheated carbon dioxide gas to prepare methanol, so that the raw material cost of the whole system can be obviously reduced, and the economic benefit of the whole system is improved.

S800: supplying the pyrolysis oil obtained in the step S600 and the combustible gas obtained in the step S700 to a power generation unit to be combusted for power generation

In this step, the pyrolysis oil obtained in S600 and the combustible gas obtained in S700 are supplied to a power generation unit to be combusted and generated so as to obtain steam and combustion off-gas, and the combustion off-gas is supplied to a carbon dioxide capture unit in S300. Specifically, the pyrolysis oil and the combustible gas can be supplied to a waste heat boiler of the power generation unit, superheated steam is generated in the waste heat boiler through heat exchange with water or combustion, the superheated steam enters a steam turbine to drive a generator to generate power, the generated electric energy is merged into a power grid, and combustion tail gas generated by the power generation unit can enter a carbon dioxide capture unit to capture and utilize carbon dioxide.

According to an embodiment of the present invention, referring to fig. 6, the method for disposing domestic garbage further includes:

s900: feeding the pyrolytic carbon into a crushing device for crushing treatment

In this step, the pyrolytic carbon is supplied to a crushing device to be crushed, so that pyrolytic carbon particles are obtained. Specifically, the garbage carbon obtained by the pyrolysis device is crushed by a crushing device to obtain garbage carbon particles with the particle size not larger than 10 mm. The inventors found that by crushing the pyrolytic char to the particle size in advance before subjecting the pyrolytic char to the gasification treatment, it is possible to significantly improve the efficiency of the gasification treatment and reduce the energy consumption of the gasification treatment.

S1000: feeding the pyrolytic carbon particles and the water vapor obtained from S800 into a gasification device for gasification treatment

In this step, the pyrolytic carbon particles and the steam obtained in S800 are supplied to a gasification apparatus to be subjected to gasification treatment, so that a gasification gas and a gasification residue are obtained. The gasification apparatus is not particularly limited, and may be selected by those skilled in the art according to the actual needs, and may be, for example, a circulating fluidized bed gasification furnace. Specifically, pyrolytic carbon particles crushed to the particle size of not more than 10mm are used as gasification raw materials and conveyed to a circulating fluidized bed gasification furnace through pressure equipment and a pipeline, water vapor and the pyrolytic carbon particles jointly enter the circulating fluidized bed gasification furnace for gasification, the gasification temperature is about 1000 ℃, gasified gas is obtained, and gasification residues can be used as building materials or landfill treatment due to low utilization value.

S1100: the gasified gas is supplied to a second energy-saving deacidification device for heat exchange and deacidification treatment

In the step, the gasified gas is supplied to a second energy-saving deacidification device for heat exchange and deacidification treatment so as to obtain the gasified gas after temperature reduction and deacidification. It should be noted that the second energy-saving deacidification apparatus may be configured in the same manner as the first energy-saving deacidification apparatus described above. Specifically, the gasified gas from the gasification device enters a second energy-saving deacidification device through a pipeline to complete waste heat recovery and deacidification, so as to obtain the gasified gas after temperature reduction and deacidification, the temperature of the gasified gas after temperature reduction and deacidification is reduced to 350 ℃, and the concentration of the acid gas is reduced to 0.02-0.05%.

S1200: the gasified gas after temperature reduction and deacidification is supplied to a gasified gas purification unit for purification treatment

In this step, the cooled and deacidified gasified gas is supplied to a gasified gas purification unit for purification treatment, so as to obtain purified gasified gas, and the purified gasified gas is returned to the pyrolysis device in S200. It should be noted that the gasification gas purification unit is not particularly limited, and may be selected by those skilled in the art according to actual needs, and may include, for example, a dust removal tower, a primary cooler, and a dry desulfurization tower connected in series. The cooled deacidified gasified gas from the second energy-saving deacidification device enters the gasified gas purification unit to realize dedusting, desulfurization, denitration and the like of the cooled deacidified gasified gas, so that H in the gasified gas is treated₂The content of S is not more than 0.01g/Nm³The content of dust is not more than 50mg/Nm³The content of benzene is not more than 20mg/Nm³The content of HCl is not more than 10mg/Nm³. After temperature reduction and deacidification, the gasified gas is sprayed by chilling circulating water to be separated into gasified gas to be purified and tar, and the tar is conveyed to an oil-water separation tank through a pipeline to be separated into tar and wastewater; the method comprises the following steps that the gasified gas to be purified is dedusted through a wet dedusting tower, the dedusted gasified gas enters a transverse pipe primary cooler after being dedusted, the primary cooler cools the dedusted gasified gas to about 21 ℃ by using two sections of cooling water of circulating water at 32 ℃ and cooling water at 16 ℃, the gasified gas discharged from the lower part of the primary cooler enters two electric tar trappers which are connected in parallel and operate simultaneously, tar entrained in the gasified gas is removed, the tar and the gasified gas to be desulfurized and denitrated are obtained, and finally the gasified gas is sent to a desulfurization and denitrification tower by a roots blower to complete desulfurization and denitrification, so that pure gasified gas is obtained.

The invention will now be described with reference to specific examples, which are intended to be illustrative only and not to be limiting in any way.

Examples

The composition of domestic garbage of a certain market is shown in table 1.

TABLE 1 composition of household garbage (wt%)

Referring to fig. 7, the household garbage is simply sorted to remove large inorganic substances and metals, and then is crushed to obtain organic garbage which meets the requirement of a rotary bed pyrolysis furnace on feeding materials, has the particle size of less than 20mm and the water content of 20 wt% -60 wt%; organic garbage is evenly fed into a rotary bed pyrolysis furnace, the thickness of the material distribution is about 100mm, the garbage in the furnace is subjected to drying, pyrolysis and activation to complete reaction along with the rotation of the furnace bottom, wherein the temperature of a drying area is 350 ℃, the temperature of a pyrolysis area is 800 ℃, the temperature of an activation area is 900 ℃, and the reaction time is 1h, so that high-temperature pyrolysis oil gas, pyrolysis carbon and pyrolysis tail gas are obtained. The composition of the pyrolysis off-gas is shown in table 2.

TABLE 2 composition of tail gas

The pyrolysis tail gas from the pyrolysis device is pressurized by a fan and fed into an absorption tower, and is in countercurrent contact with an absorbent alcohol amine solution in the absorption tower, so that CO in the pyrolysis tail gas₂Absorbed by the absorbent to become rich liquid, the rich liquid is pumped into the desorption tower to generate CO through desorption₂Mixed gas of gas, steam and mist and barren solution, desorbed CO₂Cooling by a cooler to obtain water and foam, introducing the cooled mixed gas into a gas-liquid separator, and removing the water and foam to obtain CO₂A gas. The high-temperature pyrolysis oil gas from the pyrolysis device enters a first energy-saving deacidification device through a pipeline to complete waste heat recovery and deacidification, and the high-temperature pyrolysis oilThe temperature of the gas is reduced to 200 ℃, and the concentration of the acid gas is reduced to 0.02%. The first energy-saving deacidification device can be used for collecting high-purity CO₂Preheating gas, preheated CO₂The temperature of the gas can reach 100-500 ℃. Preheated CO₂The gas and the hydrogen are compressed to 5-7MPa by a synthesis gas compressor and then enter a methanol synthesis device together, the methanol synthesis adopts one or more of oxides of copper, zinc and aluminum as a catalyst, the reaction pressure is 8.1MPa, the reaction temperature is 280 ℃, the synthesized crude methanol is rectified by a methanol rectifying tower to prepare the methanol, the yield is 3t/h, and the purity of the methanol can reach 97 percent after rectification. CO 2₂The recovery rate is more than 90 percent, the purity is more than 98 percent, simultaneously, the energy consumption of methanol synthesis can be reduced, the energy can be saved by 10 to 20 percent, and the problem of CO in the prior art is solved₂Large discharge amount, poor economic benefit and low resource utilization rate.

Pyrolysis oil gas after cooling and deacidifying from first energy-saving deacidification device enters into pyrolysis oil gas purification unit and can realize dust removal, desulfurization and denitration and the like of pyrolysis oil gas after cooling and deacidifying, so that H₂The content of S is not more than 0.01g/Nm³The content of dust is not more than 50mg/Nm³The content of benzene is not more than 20mg/Nm³The content of HCl is not more than 10mg/Nm³. Specifically, after temperature reduction and deacidification, the pyrolysis oil gas is firstly sprayed with chilling circulating water for temperature reduction and separated into pyrolysis gas to be purified and tar, and the tar is conveyed to an oil-water separation tank through a pipeline and separated into tar and wastewater; and (2) dedusting the pyrolysis gas to be purified in a wet dedusting tower, removing dust in the pyrolysis gas, then feeding the dedusted pyrolysis gas into a transverse pipe primary cooler, cooling the cooled and deacidified pyrolysis gas to about 21 ℃ by using two sections of cooling water of circulating water at 32 ℃ and cooling water at 16 ℃, feeding the cooled and deacidified pyrolysis gas discharged from the lower part of the primary cooler into two electric tar traps which are connected in parallel and operated simultaneously, removing tar carried in the cooled and deacidified pyrolysis gas to obtain pyrolysis oil and the pyrolysis gas to be desulfurized and denitrated, and finally feeding the pyrolysis gas to a desulfurization and denitrification tower by using a roots blower to complete desulfurization and denitrification to obtain clean pyrolysis gas. The composition and calorific value of the pyrolysis gas are shown in Table 3.

TABLE 3 pyrolysis gas composition and heating value

The pyrolysis gas is adsorbed by a pressure swing adsorption tower to capture hydrogen, and the hydrogen pressure swing adsorption tower purifies the hydrogen by utilizing the characteristic that an adsorbent has different adsorption capacities to adsorbates under different partial pressures and has selective adsorption to each component of a separated gas mixture under certain adsorption pressure. The pressure swing adsorption tower is formed by connecting 4 adsorption beds in parallel, the adsorption pressure range is 1-3 MPa, the adsorbent adopts activated carbon, the hydrogen recovery rate is more than 92%, the purity can reach more than 94%, and the collected hydrogen can be sent to a methanol synthesis unit to react with preheated carbon dioxide gas to prepare methanol.

The pyrolysis oil and the combustible gas are used for power generation, the economic benefit of the system can be obviously improved, and the obtained combustion tail gas can be supplied to a carbon dioxide capture unit for capturing carbon dioxide so as to be used as a raw material for producing methanol.

And crushing the garbage carbon obtained by the pyrolysis device by using a crushing device to obtain garbage carbon particles with the particle size of not more than 10 mm. The pyrolytic carbon particles crushed to the particle size of not more than 10mm are used as gasification raw materials and conveyed to a circulating fluidized bed gasification furnace through pressure equipment and a pipeline, water vapor and the pyrolytic carbon particles enter the circulating fluidized bed gasification furnace together for gasification, the gasification temperature is about 1000 ℃, gasified gas is obtained, and gasification residues can be used as building materials or landfill treatment due to low utilization value. The conversion rate of the pyrolytic carbon reaches more than 97 percent, and the calorific value of gasified gas reaches 2670Kcal/Nm³The composition and calorific value of the gasification gas are shown in Table 4.

TABLE 4 gasified gas composition and calorific value

And the gasified gas from the gasification device enters a second energy-saving deacidification device through a pipeline to complete waste heat recovery and deacidification, so that the gasified gas after temperature reduction and deacidification is obtained, the temperature of the gasified gas after temperature reduction and deacidification is reduced to 350 ℃, and the concentration of the acid gas is reduced to 0.02-0.05%. The cooled deacidified gasified gas from the second energy-saving deacidification device enters the gasified gas purification unit to realize dedusting, desulfurization, denitration and the like of the cooled deacidified gasified gas, so that H in the gasified gas is treated₂The content of S is not more than 0.01g/Nm³The content of dust is not more than 50mg/Nm³The content of benzene is not more than 20mg/Nm³The content of HCl is not more than 10mg/Nm³. After temperature reduction and deacidification, the gasified gas is firstly sprayed with chilling circulating water for temperature reduction and is separated into gasified gas to be purified and tar, and the tar is conveyed to an oil-water separation tank through a pipeline and is separated into tar and wastewater; and finally, the gasified gas after temperature reduction and deacidification discharged from the lower part of the primary cooler is sent to a desulfurization and denitrification tower by a Roots blower, desulfurization and denitrification are completed, clean gasified gas is obtained, and the purified gasified gas can be returned to a pyrolysis device to be used as fuel for pyrolysis.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art without departing from the scope of the present invention.

Claims

1. A system for treating household waste, comprising:

2. The system of claim 1, further comprising:

the pyrolysis oil gas purification unit is provided with a cooling deacidification post-pyrolysis oil gas inlet, a pyrolysis oil outlet and a pyrolysis gas outlet, and the cooling deacidification post-pyrolysis oil gas inlet is connected with the cooling deacidification post-pyrolysis oil gas outlet;

the hydrogen capture unit is provided with a pyrolysis gas inlet, a hydrogen outlet and a combustible gas outlet, the pyrolysis gas inlet is connected with the pyrolysis gas outlet, and the hydrogen outlet is connected with the hydrogen inlet;

the power generation unit is provided with a fuel inlet, a water vapor outlet and a combustion tail gas outlet, the fuel inlet is respectively connected with the pyrolysis oil outlet and the combustible gas outlet, and the combustion tail gas outlet is connected with the tail gas inlet.

3. The system of claim 1 or 2, further comprising:

the crushing device is provided with a pyrolytic carbon inlet and a pyrolytic carbon particle outlet, and the pyrolytic carbon inlet is connected with the pyrolytic carbon outlet;

the gasification device is provided with a pyrolytic carbon particle inlet, a water vapor inlet, a gasified gas outlet and a gasified residue outlet, the pyrolytic carbon particle inlet is connected with the pyrolytic carbon particle outlet, and the water vapor inlet is connected with the water vapor outlet;

the second energy-saving deacidification device is provided with a gasified gas inlet and a gasified gas outlet after temperature reduction and deacidification, and the gasified gas inlet is connected with the gasified gas outlet;

gasified gas purification unit, gasified gas purification unit has cooling deacidification back gasified gas entry and purification gasified gas export, cooling deacidification back gasified gas entry with cooling deacidification back gasified gas export links to each other, purification gasified gas export with the pyrolysis device links to each other.