CN118307200A - Melting vitrification treatment method for waste incineration fly ash - Google Patents
Melting vitrification treatment method for waste incineration fly ash Download PDFInfo
- Publication number
- CN118307200A CN118307200A CN202410520125.0A CN202410520125A CN118307200A CN 118307200 A CN118307200 A CN 118307200A CN 202410520125 A CN202410520125 A CN 202410520125A CN 118307200 A CN118307200 A CN 118307200A
- Authority
- CN
- China
- Prior art keywords
- coal
- fly ash
- air
- melting
- containing fuel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000002844 melting Methods 0.000 title claims abstract description 142
- 230000008018 melting Effects 0.000 title claims abstract description 142
- 239000010881 fly ash Substances 0.000 title claims abstract description 81
- 238000004056 waste incineration Methods 0.000 title claims abstract description 40
- 238000004017 vitrification Methods 0.000 title claims abstract description 35
- 238000000034 method Methods 0.000 title claims abstract description 30
- 239000000446 fuel Substances 0.000 claims abstract description 113
- 239000003245 coal Substances 0.000 claims abstract description 110
- 238000002485 combustion reaction Methods 0.000 claims abstract description 71
- 239000001301 oxygen Substances 0.000 claims abstract description 44
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 44
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 28
- 238000010791 quenching Methods 0.000 claims abstract description 20
- 230000000171 quenching effect Effects 0.000 claims abstract description 20
- 239000011521 glass Substances 0.000 claims abstract description 13
- 239000000126 substance Substances 0.000 claims abstract description 5
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 55
- 239000003546 flue gas Substances 0.000 claims description 55
- 239000007789 gas Substances 0.000 claims description 42
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 20
- 239000000843 powder Substances 0.000 claims description 12
- 230000009471 action Effects 0.000 claims description 10
- 238000000926 separation method Methods 0.000 claims description 6
- 239000002817 coal dust Substances 0.000 claims description 4
- 239000002803 fossil fuel Substances 0.000 claims description 4
- 230000004927 fusion Effects 0.000 claims description 2
- 238000005516 engineering process Methods 0.000 abstract description 11
- 239000002893 slag Substances 0.000 abstract description 8
- 229910018557 Si O Inorganic materials 0.000 abstract description 5
- 238000009826 distribution Methods 0.000 abstract description 5
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Inorganic materials [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 abstract description 5
- 230000009286 beneficial effect Effects 0.000 abstract description 3
- 239000002253 acid Substances 0.000 abstract description 2
- 239000007788 liquid Substances 0.000 description 11
- 238000004519 manufacturing process Methods 0.000 description 10
- 230000009467 reduction Effects 0.000 description 7
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 6
- 230000002378 acidificating effect Effects 0.000 description 5
- 230000007547 defect Effects 0.000 description 5
- HGUFODBRKLSHSI-UHFFFAOYSA-N 2,3,7,8-tetrachloro-dibenzo-p-dioxin Chemical compound O1C2=CC(Cl)=C(Cl)C=C2OC2=C1C=C(Cl)C(Cl)=C2 HGUFODBRKLSHSI-UHFFFAOYSA-N 0.000 description 4
- 229910004298 SiO 2 Inorganic materials 0.000 description 4
- 229910001385 heavy metal Inorganic materials 0.000 description 4
- 239000000155 melt Substances 0.000 description 4
- 239000002910 solid waste Substances 0.000 description 4
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 3
- 230000007246 mechanism Effects 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 239000003345 natural gas Substances 0.000 description 3
- 239000002699 waste material Substances 0.000 description 3
- 239000002956 ash Substances 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 238000007599 discharging Methods 0.000 description 2
- 238000005265 energy consumption Methods 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 239000002920 hazardous waste Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 239000004568 cement Substances 0.000 description 1
- 238000010612 desalination reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000000265 homogenisation Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 125000004435 hydrogen atom Chemical class [H]* 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Landscapes
- Gasification And Melting Of Waste (AREA)
Abstract
The invention discloses a melting vitrification treatment method of waste incineration fly ash, which comprises the following steps: the method comprises the steps of pneumatically conveying the coal-containing fuel to a high-temperature low-oxygen environment in a melting furnace for flameless combustion, pneumatically conveying fly ash to the melting furnace for melting, combining and fusing the residual inorganic substance melt obtained by burning the coal-containing fuel and the fly ash melt, and performing water quenching to form a glass body. The invention integrates the high-temperature low-oxygen flameless combustion technology and the cyclone melting technology of the coal-containing fuel with high efficiency, the flameless combustion flame volume is multiplied compared with the traditional glow flame combustion, no local high-temperature high-oxygen area exists, the temperature field distribution is very uniform, and the full combustion of the coal-containing fuel and the full melting of the residual inorganic matters are ensured. The low-price coal-containing fuel not only provides main heat for the melting of the fly ash, but also increases the acid oxide in the rest inorganic matters of the combustion of the coal-containing fuel in multiple times than the content of the fly ash, thereby being beneficial to increasing the Si-O lattice structure and improving the vitrification rate of the slag.
Description
Technical Field
The invention relates to the technical field of waste incineration fly ash treatment, in particular to a method for melting and vitrifying waste incineration fly ash.
Background
This section provides merely background information related to the present disclosure and does not necessarily constitute prior art.
The waste incineration fly ash is a secondary pollutant produced in the process of generating electricity by incineration of living waste, and is rich in more harmful substances such as heavy metal, dioxin, chloride and the like, and belongs to dangerous waste. The high-temperature melting vitrification treatment technology of the waste incineration fly ash has high capacity reduction rate, the decomposition rate of dioxin reaches 99.99 percent, and heavy metals are solidified in a glass Si-O lattice structure, so that the environmental protection risk is thoroughly eliminated.
At present, most of high-temperature melting and vitrification treatment of the waste incineration fly ash adopts a natural gas, an electric furnace or a plasma melting furnace, so that the problems of uneven temperature field and low vitrification rate are commonly existed, the energy consumption is serious, and the treatment cost is high.
Disclosure of Invention
Therefore, the invention aims to overcome the defects of nonuniform temperature field, low vitrification rate and high treatment cost existing in the existing high-temperature melting vitrification treatment technology of the waste incineration fly ash, thereby providing a melting vitrification treatment method of the waste incineration fly ash.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
a melting vitrification treatment method of waste incineration fly ash comprises the following steps:
The method comprises the steps of pneumatically conveying the coal-containing fuel to a high-temperature low-oxygen environment in a melting furnace for flameless combustion, pneumatically conveying fly ash to the melting furnace for melting, combining and fusing the residual inorganic substance melt obtained by burning the coal-containing fuel and the fly ash melt, and performing water quenching to form a glass body.
According to the technical scheme, the high-temperature environment in the high-temperature low-oxygen environment is generated by burning the gas fuel during furnace opening, and is generated by burning the gas fuel and burning the coal-containing fuel together during normal operation.
Further optimizing the technical scheme, the gaseous fuel comprises gaseous fossil fuel and green gaseous fuel.
According to the further optimized technical scheme, the melting furnace is sequentially divided into a primary cyclone melting zone and a secondary cyclone melting zone from top to bottom, the working temperature of the primary cyclone melting zone is 1200-1350 ℃, and the working temperature of the secondary cyclone melting zone is 1350-1500 ℃.
According to the technical scheme, the low-oxygen environment in the high-temperature low-oxygen environment is that the oxygen content of combustion air of coal-containing fuel is lower than 15%, and the air quantity of primary air and secondary air and the high-temperature flue gas circulation quantity are controlled.
According to the further optimized technical scheme, the fly ash is pneumatically conveyed into the melting furnace by tertiary air, and the gas fuel and the quaternary air are respectively sprayed into the melting furnace.
According to the further optimized technical scheme, the primary air, the secondary air, the tertiary air and the quaternary air are hot air after heat exchange between cold air and high-temperature flue gas exhausted by the melting furnace, and the temperatures of the primary air, the secondary air, the tertiary air and the quaternary air are 400-600 ℃.
According to the further optimized technical scheme, the rotation directions of the primary air, the secondary air, the tertiary air and the fourth air are the same, so that external rotational flow is generated in the melting furnace, and the molten melt of the residual inorganic matters and the molten melt of the fly ash generated by burning the coal-containing fuel are pushed to the furnace wall under the action of centrifugal force in the downward movement along with the external rotational flow, so that solid-gas separation and liquid-gas separation are realized; the outer rotational flow forms an inner rotational flow with the same rotation direction at the cone part at the lower part of the melting furnace, and the high-temperature flue gas is sucked into the inner rotational flow and is conveyed to an air preheating system through a high-temperature flue gas conduit.
According to the technical scheme, the high-temperature flue gas generated by burning the coal-containing fuel and the gas fuel partially flows back and is mixed with primary air and the coal-containing fuel and then is input into the melting furnace again;
the high-temperature flue gas generated by burning the coal-containing fuel and the gas fuel partially flows back, and a part of high-temperature flue gas is sucked from the high-temperature flue gas guide pipe and is input into the cyclone channel for high-temperature flue gas circulation.
Further optimizing the technical scheme, the coal-containing fuel comprises, but is not limited to, pulverized coal or gangue powder.
The technical scheme of the invention has the following advantages:
1. The method for melting and vitrifying the waste incineration fly ash provided by the invention has the advantages that the high-temperature low-oxygen flameless combustion technology and the cyclone melting technology of the coal-containing fuel are integrated efficiently, the coal-containing fuel with low price not only provides main heat (more than 70% in proportion) for melting the fly ash, but also increases the contents of acidic oxides SiO 2 and Al 2O3 in the rest inorganic matters of the coal-containing fuel combustion in multiple ways compared with the fly ash, thereby being beneficial to increasing the Si-O lattice structure and improving the vitrification rate of slag. Compared with the traditional glow flame combustion, the flameless combustion flame has the advantages that the volume is multiplied, no local high-temperature high-oxygen area exists, the temperature field is distributed uniformly, and the full combustion of the coal-containing fuel and the full melting of the residual inorganic matters are ensured. Both the reduction in flame peak temperature and the reduction in combustion zone oxygen volume concentration greatly reduce the production of NO x.
2. The invention provides a method for melting and vitrifying waste incineration fly ash, which is produced by burning gas fuel under the high-temperature condition required by flameless combustion of coal-containing fuel when a furnace is opened, and produced by burning the gas fuel and burning the coal-containing fuel together under the normal operating condition. The high temperature environment for high temperature low oxygen flameless combustion of coal-containing fuel is constructed by utilizing the high temperature generated by melting, so that a heat accumulating type burner with complex structure and high price is not required to be arranged, the defect that flame continuously jumps during reversing of heat accumulating type flameless combustion is fundamentally overcome, and flameless combustion is more stable.
3. The invention provides a melting vitrification treatment method of waste incineration fly ash, wherein coal-containing fuel comprises coal dust or coal gangue powder.
The coal-containing fuel adopts the pulverized coal and has the following advantages: the pulverized coal is subjected to low-oxygen flameless combustion in the primary cyclone melting zone, so that the air consumption is greatly reduced, the heat loss taken away by tail gas is obviously reduced, and the NO X production is greatly reduced. The coal powder has low price, the coal powder combustion provides the main heat required by melting for the melting furnace, and the coal powder accounts for more than 70% of the heat required by melting, so that the production cost is greatly reduced. The content of the acidic oxide SiO 2 in the residual inorganic matters after the pulverized coal combustion is 50-60%, the content of Al 2O3 is 15-20%, the content is multiplied higher than the content of the acidic oxide of the waste incineration fly ash (SiO 2 content-25% and Al 2O3 content-7.5%), the defect of lower acidic oxide of the waste incineration fly ash can be made up, the content of water quenching glass body is obviously improved, and the vitrification treatment is more thorough.
The coal gangue is a large amount of industrial solid waste, and in areas with rich coal gangue resources, the coal gangue powder meeting the heat value requirement is used as main fuel, so that the production cost can be greatly reduced, and the coal gangue is treated at the same time.
4. The invention provides a melting vitrification treatment method for waste incineration fly ash, which comprises the steps of partially refluxing high-temperature flue gas generated by burning coal fuel and gas fuel, mixing the high-temperature flue gas with primary air, and inputting the mixture into a melting furnace again. The high-temperature flue gas is circulated, so that the heat efficiency of an air consumption improving system and the generation amount of NO X can be reduced, and the mixing temperature of primary air and coal-containing fuel can be improved, so that the primary air carrying pulverized coal is sprayed into a primary cyclone melting zone of a 1200-1350 ℃ high-temperature melting furnace and then can be quickly heated to more than 900 ℃ to achieve the temperature condition of flameless combustion.
5. According to the method for melting and vitrifying the waste incineration fly ash, provided by the invention, a two-stage combustion melting and four-stage air distribution scheme is adopted, the two-stage combustion ensures that the temperature field distribution in the melting furnace is more uniform and reasonable, the four-stage air distribution enhances the air flow rotation, and simultaneously enhances the disturbance, so that flameless combustion of coal dust is facilitated, the fly ash is rapidly subjected to heat absorption melting, the functions of two-stage cyclone melting areas are clear and mutually supported, and the melting efficiency and the thermal efficiency of the melting furnace are greatly improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.
FIG. 1 is a block diagram of a fused vitrification treatment system for waste incineration fly ash.
Reference numerals:
1. The device comprises a fly ash melting system 11, a cyclone channel 12, cyclone blades 13, an ash spraying pipe 14, a burner 15 and a high-temperature flue gas duct;
2. the melt water quenching system comprises a melt water quenching system 21, a water quenching tank 22, a water vapor outlet 23, a slag discharging port 24 and a glass body;
3. The air preheating system comprises an air preheating system 30, cold air 31, primary air 32, secondary air 33, tertiary air 34, fourth air 35, circulating high-temperature flue gas 36, tail gas 37 and an air coil;
4. a coal-containing fuel;
5. a gaseous fuel;
6. Fly ash.
Detailed Description
Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only, and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," and "having" are inclusive and therefore specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, elements, components, and/or groups thereof.
Although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. In addition, in the description of the present invention, unless explicitly stated and limited otherwise, the terms "disposed" and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present invention can be understood by those skilled in the art according to the specific circumstances.
For ease of description, spatially relative terms, such as "front," "back," "middle," "inner," "longitudinal," "lateral," "side," "vertical," "outer," and the like, may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. Such spatially relative terms are intended to encompass different orientations of the mechanism in use or operation in addition to the orientation depicted in the figures. For example, if the mechanism in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "over" the other elements or features. Accordingly, the example term "below … …" may include both upper and lower orientations. The mechanism may be otherwise oriented (rotated 90 degrees or in other directions) and the spatial relative relationship descriptors used herein interpreted accordingly.
The waste incineration fly ash contains dioxin and heavy metals with higher concentration, has great harm to human health and ecological environment, and the national hazardous waste directory clearly stipulates that the waste incineration fly ash belongs to hazardous waste (number HW 18).
The production amount of the waste incineration fly ash in China is about 1000 ten thousand tons, most of the waste fly ash is treated in a firm landfill mode except for the coordinated treatment of a small part of cement kiln at present, and the environmental protection hidden trouble is very large.
The national standard technical requirement for solid waste vitrification treatment products (GB/T41015-2021) is implemented from 7/1/2022, and the standard prescribes that the glass body content of the solid waste vitrification treatment products is not less than 85% and the acid dissolution rate is not more than 3%.
The high-temperature melting vitrification treatment technology of the waste incineration fly ash has obvious technical advantages, the capacity reduction rate is high, the dioxin decomposition rate reaches 99.99%, the heavy metal is solidified in the Si-O lattice structure of the glass body, and the environmental protection risk is thoroughly eliminated.
At present, most of high-temperature melting and vitrification treatment of the waste incineration fly ash adopts a natural gas, an electric furnace or a plasma melting furnace, so that the problems of uneven temperature field and low vitrification rate are commonly existed, the energy consumption is serious, and the treatment cost is high.
In summary, the existing fly ash high-temperature melting vitrification treatment technology has the defect that the waste incineration fly ash cannot be reliably and economically treated.
Aiming at the technical problems, the invention adopts the scheme that the coal-containing fuel is conveyed to a high-temperature environment through low-oxygen-content gas to carry out low-oxygen flameless combustion, the temperature field in the melting furnace is uniformly distributed, the melting working space is multiplied, the melting working efficiency and the thermal efficiency of the melting furnace are greatly improved, and the exhaust nitrogen oxide discharge and the production cost are greatly reduced.
Specific examples of the present invention will be described in detail below in connection with the method for melting and vitrifying waste incineration fly ash according to the present invention.
As shown in fig. 1, the embodiment discloses a melting and vitrification treatment method for waste incineration fly ash, which utilizes a melting furnace to treat fly ash 6, wherein the furnace body comprises a cylinder arranged on the upper part and a cone arranged below the cylinder, the top of the cylinder is communicated with an air preheating system 3 through a high-temperature flue gas duct 15, and the bottom of the cone is communicated with a melt water quenching system. The processing method comprises the following steps: the coal-containing fuel 4 is conveyed into a high-temperature low-oxygen environment in a melting furnace by using air force to perform flameless combustion, the fly ash 6 is conveyed into the melting furnace by using air force to perform melting, and the residual inorganic matter molten melt of the coal-containing fuel 4 is mixed with the fly ash 6 molten melt to fuse, and the glass body is formed after water quenching.
In this embodiment, the high-temperature low-oxygen flameless combustion technology and the cyclone melting technology of the coal-containing fuel are integrated with high efficiency, the high-temperature low-oxygen flameless combustion of the coal-containing fuel complements the high-temperature melting of the coal-containing fuel and the fly ash, the coal-containing fuel 4, the primary air 31 and the circulating high-temperature flue gas 35 are input into the high-temperature environment in the melting furnace together, and after the coal-containing fuel is input into the high-temperature environment, the pulverized coal is heated to a temperature above the ignition point rapidly to generate spontaneous combustion, and the pulverized coal can be combusted stably and completely in the low-oxygen atmosphere. Compared with the traditional glow flame combustion, the flameless combustion flame has the advantages of multiplied volume expansion, no local high-temperature high-oxygen area, wider and very uniform temperature field distribution range, and full combustion of coal-containing fuel and full melting of residual inorganic matters. Both the reduction in flame peak temperature and the reduction in combustion zone oxygen volume concentration greatly reduce the production of NO x. The low-price coal-containing fuel 4 not only provides main heat (the proportion is more than 70%) for the melting of the fly ash, but also the content of acidic oxides SiO 2 and Al 2O3 in the rest inorganic matters of the combustion of the coal-containing fuel 4 is increased in multiple than that in the fly ash, which is beneficial to increasing the Si-O lattice structure and improving the vitrification rate of slag.
After the coal-containing fuel 4 is combusted, the residual inorganic matters are melted to form a high-silicon-aluminum liquid melt, the fly ash is melted to form a low-silicon-aluminum liquid melt, and the high-silicon-aluminum liquid melt and the fly ash are combined and water quenched to form a glass body.
The coal-containing fuel 4 is pulverized coal or gangue powder, and other coal-containing materials such as gasified slag may be used, and specific components thereof are not limited herein.
The coal-containing fuel 4 has the following advantages that the pulverized coal is adopted: 1. the pulverized coal is subjected to low-oxygen flameless combustion in the primary cyclone melting zone, so that the air consumption is greatly reduced, the heat loss taken away by tail gas is obviously reduced, and the NO X production is greatly reduced. 2. The coal powder has low price, the coal powder combustion provides the main heat required by melting for the melting furnace, and the coal powder accounts for more than 70% of the heat required by melting, so that the production cost is greatly reduced.
The coal gangue is a large amount of industrial solid waste, and in areas with rich coal gangue resources, the coal gangue powder meeting the heat value requirement is used as main fuel, so that the production cost can be greatly reduced, and the coal gangue is treated at the same time.
In some embodiments, the high temperature environment in the high temperature low oxygen environment is generated by combustion of the gaseous fuel 5 at furnace start-up and is generated by both combustion of the gaseous fuel 5 and combustion of the coal-containing fuel 4 at normal operating conditions.
The high-temperature air is the air temperature of the combustion-supporting coal-containing fuel which is higher than 900 ℃, the low oxygen is the oxygen content in the combustion-supporting air which is lower than 15%, the flameless combustion is the reaction time of the coal-containing fuel which is burnt in the high-temperature low-oxygen atmosphere which is prolonged, the flame volume is multiplied, and no obvious glow flame is formed.
The low oxygen environment in the high temperature low oxygen environment is that the oxygen content of the combustion air of the coal-containing fuel 4 is lower than 15 percent, and the air quantity of the primary air 31 and the secondary air 32 and the high temperature flue gas circulation quantity are controlled. The combustion air of the coal-containing fuel 4 comprises a part of circulating high-temperature flue gas 35, primary air 31 and secondary air 32, namely, the oxygen content of the mixed primary air 31, secondary air 32 and circulating high-temperature flue gas 35 is lower than 15% in a high-temperature environment, so that the low-oxygen atmosphere of the coal-containing fuel is achieved. The oxygen content in the circulating high-temperature flue gas 35 is very low, and when the circulating high-temperature flue gas 35 is introduced into a high-temperature environment and is mixed with the primary air 31 and the secondary air 32, the oxygen content in the mixed gas is reduced. And the total amount of the primary air 31 and the secondary air 32 which are input into the high-temperature environment can be controlled, so that the purpose of reducing the oxygen content is achieved.
The fly ash melting system 1 comprises a melting furnace, wherein the melting furnace is sequentially divided into a primary cyclone melting zone and a secondary cyclone melting zone from top to bottom, the working temperature of the primary cyclone melting zone is 1200-1350 ℃, the high-temperature environment of the primary cyclone melting zone is generated by gas fuel combustion during furnace opening, and the high-temperature environment is generated by gas fuel combustion and coal-containing fuel combustion during normal operation working conditions. In this embodiment, the high temperature environment is formed by burning the gaseous fuel 5 under the combined action of the four winds 34 prior to the introduction of the coal-containing fuel. After the coal-containing fuel 4 is spirally introduced through the cyclone channel 11 under the action of the cyclone blades 12 and the fly ash 6 is pneumatically conveyed and introduced through the tertiary air 33, the high-temperature environment is formed by burning the coal-containing fuel 4 and the gas fuel 5 under the combined action of a part of circulating high-temperature flue gas, primary air 31, secondary air 32, tertiary air 33 and quaternary air 34. The melting of the remaining inorganic substances after combustion in the coal-containing fuel 4 is performed in a high-temperature environment after the coal-containing fuel 4 is introduced, and the melting of the fly ash 6 is performed in a high-temperature environment after the coal-containing fuel 4 and the fly ash 6 are introduced.
The embodiment utilizes the high temperature generated by melting to construct a high temperature environment for high temperature low oxygen flameless combustion of the coal-containing fuel 4, so that a heat accumulating type burner with a complex structure and high price is not needed, the defect that the flame continuously jumps when the heat accumulating type flameless combustion is reversed is fundamentally overcome, and the flameless combustion is more stable.
In some embodiments, fly ash is pneumatically conveyed by tertiary air 33 into the melting furnace via the ash ejector 13. In this embodiment, on one hand, tertiary air 33 is utilized to push fly ash 6, so that the fly ash 6 can more conveniently enter a high-temperature environment, and on the other hand, after tertiary air 33 is mixed with fly ash 6, the temperature of the fly ash can be raised, the speed of raising the temperature to the melting temperature is increased, and the heat required by melting is saved.
The working temperature of the secondary cyclone melting zone is 1350-1500 ℃. The high-temperature environment is formed by burning coal-containing fuel 4 and gas fuel 5 under the combined action of a part of circulating high-temperature flue gas 35, primary air 31, secondary air 32, tertiary air 33 and quaternary air 34. The fly ash 6 is melted in a high temperature environment to form a liquid melt. The heat generated by the combustion of the coal-containing fuel 4 and the gas fuel 5 simultaneously provides heat for the melting of the fly ash 6, and the high-temperature environment of the secondary cyclone melting zone provides support for the high-temperature environment of the primary cyclone melting zone, and simultaneously builds up the high-temperature environment required by flameless combustion of the coal-containing fuel 4.
In some embodiments, the gaseous fuel 5 comprises a gaseous fossil fuel and a green gaseous fuel. Wherein the gaseous fossil fuel may be natural gas. The green gas fuel is hydrogen, oxyhydrogen gas and other green gas fuels.
In some embodiments, the primary air 31, the secondary air 32, the tertiary air 33, and the quaternary air 34 are hot air after the cold air 30 exchanges heat with the high temperature flue gas exhausted from the melting furnace. The temperature of the primary air 31, the secondary air 32, the tertiary air 33 and the quaternary air 34 is 400-600 ℃, the rotation directions are the same, the air flow rotation is enhanced for a plurality of times, and the disturbance is enhanced, so that the coal-containing fuel 4 can be suspended in high-temperature air for low-oxygen flameless combustion, and the fly ash 6 can be suspended in the high-temperature air for rapid temperature rising and melting.
And the rotation directions of the primary air 31, the secondary air 32, the tertiary air 33 and the quaternary air 34 are the same, external rotational flow can be generated in the melting furnace, and the molten melt of the residual inorganic matters generated by burning the coal-containing fuel 4 and the molten melt of the fly ash 6 are pushed to the furnace wall under the action of centrifugal force in the downward movement along with the external rotational flow, so that the solid-gas separation and the liquid-gas separation are realized. When the outward swirling air flow which descends in a rotating way reaches the cone, the outward swirling air flow approaches the center of the swirling cylinder due to the conical shrinkage structure. According to the principle of invariable rotation distance, the tangential speed of the motor is continuously increased. When the fluid reaches a certain position at the lower end of the cone, the fluid reversely rotates from the middle part of the cyclone cylinder to the upper part in the same rotating direction, and continuously makes spiral movement to form internal rotation airflow. The high temperature flue gas is sucked into the internal cyclone flow and is conveyed to the air preheating system through the high temperature flue gas conduit 15.
In some embodiments, the high temperature flue gas generated by the combustion of the coal-containing fuel 4 and the gaseous fuel 5 is partially recirculated and mixed with the primary air 31 and the coal-containing fuel before being fed into the melting furnace again. The high-temperature flue gas is circulated, so that the heat efficiency of an air consumption improving system and the generation amount of NO X can be reduced, and the mixing temperature of primary air 31 and coal-containing fuel 4 can be improved, so that the primary air carrying the coal-containing fuel 4 is sprayed into a primary cyclone melting zone of a 1200-1350 ℃ high-temperature melting furnace and then can be quickly heated to more than 900 ℃ to achieve the temperature condition of flameless combustion.
More specifically, the high-temperature flue gas generated by the combustion of the coal-containing fuel 4 and the gas fuel 5 partially flows back, and a part of the high-temperature flue gas is sucked from the high-temperature flue gas guide pipe 15 and is input into the cyclone channel 11 for high-temperature flue gas circulation. In this embodiment, the high-temperature flue gas duct 15 is a connection part between the melting furnace and the air preheating system 3, so that the high-temperature flue gas in the high-temperature flue gas duct 15, which does not exchange heat with cold air, can be pumped through the high-temperature flue gas circulation pipeline, and the high-temperature flue gas flowing back to the cyclone channel 11 is ensured to have a higher temperature, so that the coal-containing fuel 4 can be heated rapidly.
In some embodiments, the air preheating system 3 comprises a heat exchanger housing and an air coil 37, wherein the bottom of the heat exchanger housing is communicated with the top of the melting furnace, and two opposite side walls of the heat exchanger housing are sequentially provided with a cold air 30 inlet, a heat exchanged gas outlet and a tail gas 36 outlet. The air coil 37 is filled with cold air 30 to be preheated, the cold air 30 exchanges heat with high-temperature flue gas in the heat exchanger shell, tail gas 36 after heat exchange and temperature reduction is discharged through a tail gas outlet, and the hot air after heat exchange forms primary air 31, secondary air 32, tertiary air 33 and quaternary air 34 which are respectively filled in different positions of the melting furnace.
In some embodiments, melt water quenching system 2 includes a water quenching tank 21, a water vapor outlet 22, and a slag tap 23. The water quenching tank 21 is arranged at the bottom end of the cone of the melting furnace and contains liquid water. The steam outlet 22 is disposed at an upper portion of a side wall of the water quenching tank, and is adapted to discharge steam generated by water quenching from the steam outlet 22. The slag discharging port 23 is provided at a lower portion of a side wall of the water quenching tank 21, and adapted to discharge a glass body 24 produced by water quenching.
Taking coal-containing fuel 4 as coal dust as an example, the specific treatment method of the waste incineration fly ash melting vitrification treatment method comprises the following steps:
Firstly, gas fuel 5 is sprayed into a melting furnace through a burner 14 for combustion, four-time air 34 is sprayed into the melting furnace for combustion supporting, the melting furnace is heated, primary air 31, circulating high-temperature flue gas 35 and secondary air 32 are respectively introduced into the top of the furnace body, the hearth temperature of the primary cyclone melting zone of the melting furnace is increased to 1200-1350 ℃, and the working temperature of pulverized coal low-oxygen flameless combustion and low-oxygen atmosphere are achieved.
Then, the pulverized coal is driven by the primary air 31 conveyed by the air preheating system 3 and part of the circulating high-temperature flue gas 35 is sprayed into the furnace from the top of the melting furnace, and at the moment, the oxygen content of the primary air 31, the secondary air 32 and the part of the circulating high-temperature flue gas 35 after being mixed is lower than 15 percent. The primary air 31 and the part of circulating high-temperature flue gas 35 are mixed with pulverized coal and enter a melting furnace to be quickly heated to more than 900 ℃, low-oxygen flameless combustion is carried out in a cyclone flow, so that the working temperature of a primary cyclone melting zone is kept at 1200-1350 ℃, heat is provided for a secondary cyclone melting zone through furnace wall heat radiation and cyclone heat conduction, inorganic matters remained in pulverized coal combustion are melted in the cyclone and pushed to the furnace wall under the action of centrifugal force, a high-silicon aluminum liquid melt forms a melting film on the furnace wall, a small amount of pulverized coal which is not burned out in the cyclone continues to burn on the melting film, the inorganic matters are melted, and the high-silicon aluminum liquid melt flows down the furnace wall under the action of gravity.
The gas fuel 5 is burnt in the secondary cyclone melting zone and acts together with the heat generated by the burning of the pulverized coal, so that the working temperature of the secondary cyclone melting zone reaches 1350-1500 ℃.
Then, the waste incineration fly ash after the water washing desalination pretreatment enters a secondary cyclone melting zone in a melting furnace under the drive of tertiary air 33, the fly ash 6 is quickly heated in the cyclone flow and is pushed to the furnace wall by centrifugal force, and a low-silicon aluminum liquid melt is formed after melting and flows down along the furnace wall under the action of gravity. The high-silicon aluminum liquid melt generated by melting residual inorganic matters in pulverized coal combustion and the low-silicon aluminum liquid melt generated by melting waste incineration fly ash are converged on the furnace wall, overlapped, added, matched and fused in the process of flowing down along the cylindrical furnace wall and the conical reducing pipe at the lower part of the melting furnace, and enter a water quenching system after being homogenized.
Finally, the liquid melt after compatibility, fusion and homogenization enters a water quenching tank 21 to be water quenched into a glass body 24, the glass body 24 is discharged through a slag discharge port 23, and water vapor generated by water quenching is discharged through a water vapor outlet 22.
The high-temperature flue gas generated by the combustion of the fuel in the primary and secondary cyclone melting areas in the melting furnace is rolled up by the internal rotation air flow, a part of the high-temperature flue gas is extracted in the high-temperature flue gas duct 15 and introduced into the primary air cyclone channel, and the rest part of the high-temperature flue gas enters the air preheating system 3 to perform full heat exchange, so that the air preheating temperature reaches 400-600 ℃, the temperature of the combustion tail gas is reduced to below 900 ℃, and standard emission is achieved after the conventional tail gas system treatment.
It should be noted that, the melt water quenching system 2, the air preheating system 3 and the tail gas treatment for reducing the temperature to below 900 ℃ are all mature technologies, and needless to say, the embodiment only makes the simplest description.
It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. And obvious variations or modifications thereof are contemplated as falling within the scope of the present invention.
Claims (10)
1. The melting vitrification treatment method of the waste incineration fly ash is characterized by comprising the following steps of:
The method comprises the steps of pneumatically conveying the coal-containing fuel to a high-temperature low-oxygen environment in a melting furnace for flameless combustion, pneumatically conveying fly ash to the melting furnace for melting, combining and fusing the residual inorganic substance melt obtained by burning the coal-containing fuel and the fly ash melt, and performing water quenching to form a glass body.
2. The method for vitrification treatment of waste incineration fly ash according to claim 1, wherein the high temperature environment in the high temperature low oxygen environment is generated by combustion of a gas fuel at the time of furnace opening and is generated by combustion of the gas fuel and combustion of a coal-containing fuel together at the time of normal operation.
3. The method for vitrification of waste incineration fly ash according to claim 2, wherein the gaseous fuel includes gaseous fossil fuel and green gaseous fuel.
4. A waste incineration fly ash melting vitrification treatment method according to any one of claims 1 to 3, wherein the melting furnace is divided into a primary cyclone melting zone and a secondary cyclone melting zone in sequence from top to bottom, the working temperature of the primary cyclone melting zone is 1200-1350 ℃, and the working temperature of the secondary cyclone melting zone is 1350-1500 ℃.
5. A method for vitrification of waste incineration fly ash according to any one of claims 1 to 3, wherein the low oxygen environment in the high temperature low oxygen environment is that the oxygen content of combustion air of coal-containing fuel is lower than 15%, and is produced by controlling the air volume of primary air and secondary air and the circulation amount of high temperature flue gas.
6. The method for vitrification of waste incineration fly ash according to claim 5, wherein the fly ash is pneumatically conveyed into the melting furnace by tertiary air, and the gas fuel and the quaternary air are respectively injected into the melting furnace.
7. The method for vitrification treatment of waste incineration fly ash according to claim 6, wherein the primary air, the secondary air, the tertiary air and the quaternary air are hot air after heat exchange between cold air and high-temperature flue gas discharged from the melting furnace, and the temperatures of the primary air, the secondary air, the tertiary air and the quaternary air are 400-600 ℃.
8. The method for vitrification of waste incineration fly ash according to claim 7, wherein the primary air, the secondary air, the tertiary air and the quaternary air are rotated in the same direction to generate an external swirl flow in the melting furnace, and the molten melt of the residual inorganic matters of the combustion of the coal-containing fuel and the molten melt of the fly ash are pushed to the furnace wall under the action of centrifugal force in the downward movement along with the external swirl flow, thereby realizing solid-gas separation and liquid-gas separation; the outer rotational flow forms an inner rotational flow with the same rotation direction at the cone part at the lower part of the melting furnace, and the high-temperature flue gas is sucked into the inner rotational flow and is conveyed to an air preheating system through a high-temperature flue gas conduit.
9. A waste incineration fly ash melting vitrification treatment method according to any one of claims 1 to 3, wherein the high temperature flue gas generated by the combustion of the coal-containing fuel and the gas fuel partially flows back and is mixed with primary air and the coal-containing fuel and then is input into the melting furnace again;
the high-temperature flue gas generated by burning the coal-containing fuel and the gas fuel partially flows back, and a part of high-temperature flue gas is sucked from the high-temperature flue gas guide pipe and is input into the cyclone channel for high-temperature flue gas circulation.
10. A waste incineration fly ash fusion vitrification treatment method according to any one of claims 1-3, characterized in that the coal-containing fuel comprises coal dust or coal gangue powder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410520125.0A CN118307200A (en) | 2024-04-26 | 2024-04-26 | Melting vitrification treatment method for waste incineration fly ash |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410520125.0A CN118307200A (en) | 2024-04-26 | 2024-04-26 | Melting vitrification treatment method for waste incineration fly ash |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118307200A true CN118307200A (en) | 2024-07-09 |
Family
ID=91720701
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410520125.0A Pending CN118307200A (en) | 2024-04-26 | 2024-04-26 | Melting vitrification treatment method for waste incineration fly ash |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN118307200A (en) |
-
2024
- 2024-04-26 CN CN202410520125.0A patent/CN118307200A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106594763B (en) | Rotary kiln, plasma melting furnace combined type dangerous waste disposal system | |
| CN1759941B (en) | New type heating and fusing method and equipment for dealing with flying ash generated by burning garbage | |
| CN206709079U (en) | The small-sized domestic garbage pyrolysis processing system of villages and small towns level | |
| CN1172111C (en) | Slag incinerator for treating hazardous wastes and medical garbage and process method | |
| CN105737140B (en) | Cyclone combustion device, combustion equipment and combustion method | |
| CN106949479A (en) | The small-sized domestic garbage pyrolysis processing system of villages and small towns level | |
| CN112254133A (en) | Novel dangerous waste combustion online coupling plasma melting integrated system | |
| CN105864782A (en) | Device and method for heating and melting rubbish under oxygen-rich condition | |
| CN111250510B (en) | Flying ash melting treatment device and flying ash melting treatment method operating in sections | |
| CN105222585A (en) | The combustion-supporting energy-saving aluminium-melting furnace of small-sized flue gas | |
| CN201827897U (en) | Environment-friendly chemical saliferous waste water incinerator | |
| CN105465791A (en) | Fly ash disposal system | |
| JPH0629566B2 (en) | Coal burning boiler | |
| CN102506433B (en) | L-shaped combined high-temperature electronic garbage incinerator | |
| CN202066349U (en) | Reciprocating porous medium gas combustion metal smelting furnace | |
| CN102380501B (en) | U-shaped high-temperature waste recycling furnace | |
| CN118307200A (en) | Melting vitrification treatment method for waste incineration fly ash | |
| CN102243016A (en) | Reciprocating type porous medium gas burning metal smelting furnace | |
| CN216480987U (en) | Melting furnace and treatment system for solid hazardous waste treatment | |
| KR100311904B1 (en) | Method and system for incinerating garbage by high temperature thermal decomposition action of gas amplified plasma | |
| CN104214782A (en) | Garbage treatment rotary kiln system | |
| CN107166400A (en) | House refuse integration heat treatment system and method | |
| CN115218197A (en) | Flue gas recirculation air distribution method | |
| CN111351028B (en) | Cyclone airflow field combustion chamber | |
| CN205710615U (en) | The pulverized coal gasification furnace that a kind of preheated air enters with eddy flow |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |