CN113432129A - Cement kiln treatment process for municipal sludge - Google Patents
Cement kiln treatment process for municipal sludge Download PDFInfo
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- CN113432129A CN113432129A CN202110703567.5A CN202110703567A CN113432129A CN 113432129 A CN113432129 A CN 113432129A CN 202110703567 A CN202110703567 A CN 202110703567A CN 113432129 A CN113432129 A CN 113432129A
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- 238000000034 method Methods 0.000 title claims abstract description 28
- 230000008569 process Effects 0.000 title claims abstract description 27
- 239000007789 gas Substances 0.000 claims abstract description 27
- 238000012216 screening Methods 0.000 claims abstract description 8
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- 238000003795 desorption Methods 0.000 claims abstract description 6
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- 230000009194 climbing Effects 0.000 claims description 9
- 238000000265 homogenisation Methods 0.000 claims description 9
- 238000003860 storage Methods 0.000 claims description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 6
- 239000002245 particle Substances 0.000 claims description 6
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- 239000000126 substance Substances 0.000 claims description 6
- 239000002994 raw material Substances 0.000 claims description 5
- 239000002912 waste gas Substances 0.000 claims description 5
- 235000019738 Limestone Nutrition 0.000 claims description 3
- 238000010521 absorption reaction Methods 0.000 claims description 3
- 239000002253 acid Substances 0.000 claims description 3
- 230000005540 biological transmission Effects 0.000 claims description 3
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- 239000003292 glue Substances 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 3
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- 239000000843 powder Substances 0.000 claims description 3
- 230000002265 prevention Effects 0.000 claims description 3
- 238000012545 processing Methods 0.000 claims description 3
- 230000002441 reversible effect Effects 0.000 claims description 3
- 239000000463 material Substances 0.000 abstract description 6
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- 235000011941 Tilia x europaea Nutrition 0.000 description 1
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- VUZPPFZMUPKLLV-UHFFFAOYSA-N methane;hydrate Chemical compound C.O VUZPPFZMUPKLLV-UHFFFAOYSA-N 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 description 1
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Images
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G7/00—Incinerators or other apparatus for consuming industrial waste, e.g. chemicals
- F23G7/001—Incinerators or other apparatus for consuming industrial waste, e.g. chemicals for sludges or waste products from water treatment installations
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B7/00—Hydraulic cements
- C04B7/24—Cements from oil shales, residues or waste other than slag
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B7/00—Hydraulic cements
- C04B7/36—Manufacture of hydraulic cements in general
- C04B7/43—Heat treatment, e.g. precalcining, burning, melting; Cooling
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G5/00—Incineration of waste; Incinerator constructions; Details, accessories or control therefor
- F23G5/006—General arrangement of incineration plant, e.g. flow sheets
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G5/00—Incineration of waste; Incinerator constructions; Details, accessories or control therefor
- F23G5/02—Incineration of waste; Incinerator constructions; Details, accessories or control therefor with pretreatment
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G5/00—Incineration of waste; Incinerator constructions; Details, accessories or control therefor
- F23G5/08—Incineration of waste; Incinerator constructions; Details, accessories or control therefor having supplementary heating
- F23G5/14—Incineration of waste; Incinerator constructions; Details, accessories or control therefor having supplementary heating including secondary combustion
- F23G5/16—Incineration of waste; Incinerator constructions; Details, accessories or control therefor having supplementary heating including secondary combustion in a separate combustion chamber
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G5/00—Incineration of waste; Incinerator constructions; Details, accessories or control therefor
- F23G5/20—Incineration of waste; Incinerator constructions; Details, accessories or control therefor having rotating or oscillating drums
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G5/00—Incineration of waste; Incinerator constructions; Details, accessories or control therefor
- F23G5/44—Details; Accessories
- F23G5/442—Waste feed arrangements
- F23G5/444—Waste feed arrangements for solid waste
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23G—CREMATION FURNACES; CONSUMING WASTE PRODUCTS BY COMBUSTION
- F23G7/00—Incinerators or other apparatus for consuming industrial waste, e.g. chemicals
- F23G7/06—Incinerators or other apparatus for consuming industrial waste, e.g. chemicals of waste gases or noxious gases, e.g. exhaust gases
- F23G7/061—Incinerators or other apparatus for consuming industrial waste, e.g. chemicals of waste gases or noxious gases, e.g. exhaust gases with supplementary heating
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J15/00—Arrangements of devices for treating smoke or fumes
- F23J15/003—Arrangements of devices for treating smoke or fumes for supplying chemicals to fumes, e.g. using injection devices
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J2215/00—Preventing emissions
- F23J2215/20—Sulfur; Compounds thereof
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/10—Production of cement, e.g. improving or optimising the production methods; Cement grinding
Abstract
The invention relates to a cement kiln treatment process for municipal sludge, which comprises the following steps: 1) piling up the municipal sludge; 2) screening the municipal sludge; 3) the municipal sludge is closely transmitted, prevented from being adhered and homogenized; 4) metering the fed materials; 5) treating the rotary cement kiln: controlling the temperature of the rotary cement kiln at 900-1000 ℃, controlling the kiln speed of the rotary cement kiln at 1.5-2.0 r/min, and ensuring that the retention time of sludge in the rotary cement kiln is more than or equal to 30min to form inorganic residues capable of being comprehensively utilized; 6) tail gas incineration: and tail gas generated in the thermal desorption process in the cement rotary kiln enters a decomposing furnace for high-temperature burning treatment, the temperature in the decomposing furnace is controlled to be 1000-1200 ℃, the temperature at the outlet of the decomposing furnace is controlled to be 880-920 ℃, and the burning retention time of the tail gas in the decomposing furnace is more than 3 seconds. The invention realizes the reduction, stabilization, harmlessness and resource treatment of the municipal sludge and prevents harmful gases from escaping.
Description
Technical Field
The invention belongs to the technical field of municipal sludge treatment, and particularly relates to a cement kiln treatment process for municipal sludge.
Background
The municipal sludge refers to sludge substances which are not hazardous wastes, such as sewage sludge, general industrial sludge, river sludge, sludge of sewage treatment plants and the like. The municipal sludge contains a large amount of organic matters and harmful substances, and bacteria breed, so that various pollutions are caused, and a place is provided for breeding other harmful organisms; the urban sludge stacked in the open can emit odor and peculiar smell, and influence the surrounding living environment; the sludge is pulverized by sun-drying wind, the generated pollutant particles can cause atmospheric pollution, and the pollutants flow into a river channel along with sewage after being soaked and dissolved by water, can pollute surface water and further enter underground water; the heavy metal content in the municipal sludge is high, and the soil at the stacking position can be polluted.
At present, the municipal sludge treatment technology in China is mainly divided into the following three directions: wherein land utilization is taken as a main disposal direction, such as anaerobic digestion technology, aerobic composting technology and the like; process technologies such as lime stabilization technology, fixation stabilization technology and the like which take building material utilization as a disposal direction; the process technology takes municipal sludge incineration as a disposal direction, such as sludge blending combustion disposal of a thermal power plant, and municipal sludge co-disposal of a rotary cement kiln.
The urban sludge treatment technology has the conditions of single treatment form, low degree of stabilization and reduction, insufficient treatment capacity and the like on the whole, and some technologies can also form secondary pollution. The method treats the municipal sludge by relying on a high-temperature furnace kiln device, and has the characteristics of thorough organic matter cracking, no leaching of heavy metal during high-temperature curing, no secondary pollution, high recycling efficiency, large treatment capacity, stable process, no additional investment and the like. However, since the water content of the municipal sludge is higher, generally 40-50%, and some of the municipal sludge even reach 70-80%, and the organic matter content and the heavy metal content are unstable, the following problems exist in the disposal process:
1. because the water content of the municipal sludge is higher, the problems of belt adhesion, unsmooth discharging, material blockage in the transfer link and the like easily occur in the handling and transportation link.
2. Because municipal sludge contains volatile organic matters, flue gas containing volatile organic carbon analyzed by the kiln system enters a waste gas system without being fully burnt by the decomposing furnace, so that the organic matters discharged by tail gas exceed the standard, and the tail gas meets open fire and is easy to flash and explode, thereby causing safety accidents.
3. Heavy metals in municipal sludge cannot be well controlled.
Disclosure of Invention
The invention provides a cement kiln treatment process for municipal sludge, which aims to solve the technical problems in the prior art, realizes reduction, stabilization, harmlessness and resource treatment of municipal sludge, and simultaneously prevents harmful gas from escaping.
The technical scheme adopted by the invention for solving the technical problems in the prior art is as follows:
a cement kiln treatment process for municipal sludge comprises the following steps:
1) and (3) piling up the municipal sludge: unloading the urban sludge into a designated storage site after the urban sludge enters the plant, performing anti-seepage treatment on the storage site, and well covering;
2) screening municipal sludge: carrying out primary screening and iron removal treatment on the sludge, and controlling the particle size to be less than 100 mm;
3) closed transmission, adhesion prevention and homogenization of municipal sludge: conveying the screened municipal sludge to a closed pre-homogenization shed by a belt conveyor;
4) feeding and metering: after mechanical homogenization, the cement is fed into a raw material metering bin through a ground surface feeder, and is metered by a constant feeder below the bin, and then is fed into a kiln through a reversible belt, a climbing belt and a smoke inlet chamber belt conveyor and a tail smoke chamber of a cement rotary kiln;
5) treating the rotary cement kiln: controlling the temperature of the cement rotary kiln at 900 ℃ and 1000 ℃ to ensure the stable combustion of flame; controlling the kiln speed of the rotary cement kiln to be 1.5-2.0 r/min, and ensuring that the retention time of sludge in the rotary cement kiln is more than or equal to 30min, so that volatile substances such as water, organic matters and the like in the sludge are fully analyzed, and inorganic residues capable of being comprehensively utilized are formed;
6) tail gas incineration: the tail gas generated in the thermal desorption process in the cement rotary kiln enters a decomposing furnace for high-temperature incineration treatment, pulverized coal is sprayed into the decomposing furnace for combustion, stable combustion of the secondary combustion of the kiln tail is guaranteed, the temperature in the decomposing furnace is controlled to be 1000-1200 ℃, the temperature at the outlet of the decomposing furnace is controlled to be 880-920 ℃, and the incineration retention time of the tail gas in the decomposing furnace is longer than 3 seconds.
Preferably, the thermal ignition loss of the inorganic residue after the treatment is controlled to be less than 5%, and the water content is controlled to be less than 1.0%.
Preferably, the temperature in the decomposing furnace is controlled at 1100 ℃.
Preferably, in the step 3) and the step 4), the municipal sludge is conveyed in a closed manner when conveyed by a belt.
Preferably, climbing band conveyer carries out antiseized glutinous processing, specifically for through scattering cement rotary kiln waste gas back ash on climbing belt, makes municipal sludge not direct contact conveyor belt, prevents that conveyor belt glues glutinous.
Preferably, the hopper of the surface feeder is a vertical surface.
Preferably, limestone powder is also sprayed into the decomposing furnace for dry desulfurization and acid gas absorption.
Compared with the prior art, the invention has the advantages and positive effects that:
1) the invention makes full use of the original facilities of the cement rotary kiln, reduces the investment and avoids repeated construction.
2) The municipal sludge is subjected to countercurrent heat exchange with kiln head hot air in the cement rotary kiln to desorb and analyze moisture and volatile harmful components in the municipal sludge, and the flue gas containing the harmful components is fully cracked and incinerated by utilizing the high temperature of the kiln tail fuel, so that organic matters and volatile components in the municipal sludge are fully volatilized, and the reduction, harmless, safe and inorganic treatment of the municipal sludge is realized.
3) The municipal sludge subjected to thermal desorption, cracking and incineration enters a cooler to be cooled and then is sent to the existing clinker warehouse, and is transported to a storage yard to be used as a part of substitute raw materials to be mixed and recycled for producing cement clinker, so that waste is changed into valuable, and the high-efficiency utilization of resources is realized. The inorganic residue can also be comprehensively utilized as a raw material of other building material products.
4) The tail gas generated in the thermal desorption process adopts a secondary combustion burning technology, so that organic matters contained in the waste gas are fully burned and harmlessly decomposed.
5) The invention improves the pre-screening and material transportation links with pertinence, optimizes the sequence of the process, and ensures the smooth process of conveying and blanking the municipal sludge.
Drawings
FIG. 1 is a process flow diagram of the present invention;
fig. 2 is a schematic structural view of a hopper of the surface feeder of the present invention.
Detailed Description
In order to further understand the contents, features and effects of the present invention, the following embodiments are illustrated and described in detail with reference to the accompanying drawings:
examples
A cement kiln treatment process for municipal sludge comprises the following steps:
1) and (3) piling up the municipal sludge: unloading the urban sludge into a designated storage site after the urban sludge enters the plant, performing anti-seepage treatment on the storage site, and well covering;
2) screening municipal sludge: carrying out primary screening and iron removal treatment on the sludge, and controlling the particle size to be less than 100 mm;
3) closed transmission, adhesion prevention and homogenization of municipal sludge: conveying the screened municipal sludge to a closed pre-homogenization shed by a belt conveyor;
4) feeding and metering: after mechanical homogenization, the cement is fed into a raw material metering bin through a ground surface feeder, and is metered by a constant feeder below the bin, and then is fed into a kiln through a reversible belt, a climbing belt and a smoke inlet chamber belt conveyor and a tail smoke chamber of a cement rotary kiln;
5) treating the rotary cement kiln: controlling the temperature of the cement rotary kiln at 900 ℃ and 1000 ℃ to ensure the stable combustion of flame; controlling the kiln speed of the rotary cement kiln to be 1.5-2.0 r/min, and ensuring that the retention time of sludge in the rotary cement kiln is more than or equal to 30min, so that volatile substances such as water, organic matters and the like in the sludge are fully analyzed, and inorganic residues capable of being comprehensively utilized are formed; the thermal ignition loss rate of the inorganic residues after treatment is controlled to be below 5 percent, the moisture content is controlled to be below 1.0 percent, the full incineration treatment of the rotary cement kiln is ensured, the urban sludge is treated specially in a large scale, and the generated reduced inorganic residues (which are 30 to 40 percent of the mass of the original sludge) can be comprehensively utilized in a large scale.
The calcination temperature is controlled mainly, so that not only can volatile substances in the municipal sludge be sufficiently analyzed and volatilized, but also the conditions of no generation of burning flow, ring formation and the like of residues are ensured, partial particles are formed in the optimal state, and the subsequent synergistic treatment of the rotary cement kiln is facilitated; the non-volatile heavy metals such as nickel, manganese and the like contained in the municipal sludge are solidified in the residue in the form of residue after being treated, and the volatile heavy metals such as lead, zinc and the like are circulated and enriched in the kiln and finally solidified in the residue in the form of residue.
6) Tail gas incineration: and tail gas generated in the thermal desorption process in the cement rotary kiln enters a decomposing furnace for high-temperature incineration treatment, pulverized coal is sprayed into the decomposing furnace for combustion, stable combustion of the secondary combustion of the kiln tail is guaranteed, the temperature in the decomposing furnace is controlled to be 1000-1200 ℃, preferably 1100 ℃, the temperature at the outlet of the decomposing furnace is controlled to be 880-920 ℃, and the incineration residence time of the tail gas in the decomposing furnace is more than 3 seconds.
Various harmful organic matters contained in the tail gas are fully burnt to generate carbon dioxide and water, and the tail gas is ensured to be discharged up to the standard by matching with the existing flue gas treatment facility of the rotary cement kiln.
Preferably, in the step 3) and the step 4), the municipal sludge is conveyed in a closed manner when conveyed by the belt, so that no sprinkling and no odor overflow are ensured.
Climbing band conveyer carries out antiseized glutinous processing, specifically is through scattering cement rotary kiln waste gas ash back on climbing belt, makes municipal sludge not direct contact conveyor belt, prevents that conveyor belt glues glutinous.
The hopper of the surface feeder is a vertical surface, and an inclined surface is changed into the vertical surface, so that material accumulation is prevented. This embodiment increases the hopper backplate simultaneously and meets 1.5m of flitch, guarantees that the material does not spill.
In order to ensure that the tail gas of the system meets the requirement of environmental protection emission, limestone powder is also sprayed into the decomposing furnace for dry desulfurization and acid gas absorption. Inhibition of SO2Production of gas according to NOXTimely opening of the denitration system for emission to reduce NOXIs generated.
The set of experimental conditions for the different thermal treatment technical tests of municipal sludge is further illustrated as follows:
carrying out thermogravimetry-mass spectrometry-infrared online experiments on the municipal sludge sample, and researching the volatilization and combustion characteristics of the municipal sludge sample at high temperature:
according to thermogravimetric experiments, the incineration can be divided into the following three stages:
the first stage is as follows: the temperature was set at-220 ℃ and the mass loss was about 75% during the rapid mass decrease period, which is presumed to be mainly due to water evaporation and inclusion of a part of organic gas. In actual operation, the kiln is in a negative pressure environment, the exhaust amount is large (more than 20 ten thousand square meters per hour), and water vapor generated by heating municipal sludge can be timely discharged. According to the estimation of mass spectrometry, the organic gas is mainly olefin, and the organic gas generated during the actual treatment enters a 900 ℃ decomposition furnace to be sufficiently combusted and decomposed.
And a second stage: 220-900 ℃ and the quality is slowly reduced, and the quality loss is about 18 percent.
And a third stage: above 900 ℃, during the period of stable quality, although very small amounts of particles and gaseous compounds are produced, the total mass of the sample solid is considered to be hardly changed. When the temperature is higher than 900 ℃, the material in the rotary kiln can be treated.
According to the test result of municipal sludge incineration, the acquired municipal sludge has small thermogravimetric change and basically stable heavy metal pollutants when heated to 900 ℃, and the system parameter value is preliminarily determined by referring to the actual process requirement of rotary cement kiln treatment.
TABLE 1 control parameters and values
According to thermogravimetric experimental data, the burning temperature of the rotary cement kiln is set to be 900-1000 ℃, organic matters and volatile components in the municipal sludge are fully volatilized, and burned, and finally formed burning residues needing secondary treatment are formed. The volatilized organic matters enter the kiln tail decomposing furnace along with the flue gas to be fully incinerated.
The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention in any way, and all simple modifications, equivalent changes and modifications made to the above embodiment according to the technical spirit of the present invention are within the scope of the technical solution of the present invention.
Claims (7)
1. The cement kiln treatment process of the municipal sludge is characterized by comprising the following steps of:
1) and (3) piling up the municipal sludge: unloading the urban sludge into a designated storage site after the urban sludge enters the plant, performing anti-seepage treatment on the storage site, and well covering;
2) screening municipal sludge: carrying out primary screening and iron removal treatment on the sludge, and controlling the particle size to be less than 100 mm;
3) closed transmission, adhesion prevention and homogenization of municipal sludge: conveying the screened municipal sludge to a closed pre-homogenization shed by a belt conveyor;
4) feeding and metering: after mechanical homogenization, the cement is fed into a raw material metering bin through a ground surface feeder, and is metered by a constant feeder below the bin, and then is fed into a kiln through a reversible belt, a climbing belt and a smoke inlet chamber belt conveyor and a tail smoke chamber of a cement rotary kiln;
5) treating the rotary cement kiln: controlling the temperature of the cement rotary kiln at 900 ℃ and 1000 ℃ to ensure the stable combustion of flame; controlling the kiln speed of the rotary cement kiln to be 1.5-2.0 r/min, and ensuring that the retention time of sludge in the rotary cement kiln is more than or equal to 30min, so that volatile substances such as water, organic matters and the like in the sludge are fully analyzed, and inorganic residues capable of being comprehensively utilized are formed;
6) tail gas incineration: the tail gas generated in the thermal desorption process in the cement rotary kiln enters a decomposing furnace for high-temperature incineration treatment, pulverized coal is sprayed into the decomposing furnace for combustion, stable combustion of the secondary combustion of the kiln tail is guaranteed, the temperature in the decomposing furnace is controlled to be 1000-1200 ℃, the temperature at the outlet of the decomposing furnace is controlled to be 880-920 ℃, and the incineration retention time of the tail gas in the decomposing furnace is longer than 3 seconds.
2. The cement kiln treatment process of municipal sludge according to claim 1, characterized in that: the thermal ignition loss of the inorganic residue after treatment is controlled below 5 percent, and the water content is controlled below 1.0 percent.
3. The cement kiln treatment process of municipal sludge according to claim 1, characterized in that: the temperature in the decomposing furnace is controlled at 1100 ℃.
4. The cement kiln treatment process of municipal sludge according to claim 1, characterized in that: in the step 3) and the step 4), the municipal sludge is conveyed in a closed manner when conveyed by the belt.
5. The cement kiln treatment process of municipal sludge according to claim 1, characterized in that: climbing band conveyer carries out antiseized glutinous processing, specifically is through scattering cement rotary kiln waste gas ash back on climbing belt, makes municipal sludge not direct contact conveyor belt, prevents that conveyor belt glues glutinous.
6. The cement kiln treatment process of municipal sludge according to claim 1, characterized in that: the hopper of the surface feeder is a vertical surface.
7. The cement kiln treatment process of municipal sludge according to claim 1, characterized in that: limestone powder is also sprayed into the decomposing furnace for dry desulfurization and acid gas absorption.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104329675A (en) * | 2014-11-07 | 2015-02-04 | 西安建筑科技大学 | Method for incinerating sludge by using kiln tail system of cement plant |
| CN106986566A (en) * | 2017-06-02 | 2017-07-28 | 天津振兴水泥有限公司 | A kind of disposing technique of the Polluted Soil containing cyanogen |
| CN107790480A (en) * | 2017-10-26 | 2018-03-13 | 天津中材工程研究中心有限公司 | It is a kind of to utilize the method for transforming cement kiln processing Polluted Soil |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104329675A (en) * | 2014-11-07 | 2015-02-04 | 西安建筑科技大学 | Method for incinerating sludge by using kiln tail system of cement plant |
| CN106986566A (en) * | 2017-06-02 | 2017-07-28 | 天津振兴水泥有限公司 | A kind of disposing technique of the Polluted Soil containing cyanogen |
| CN107790480A (en) * | 2017-10-26 | 2018-03-13 | 天津中材工程研究中心有限公司 | It is a kind of to utilize the method for transforming cement kiln processing Polluted Soil |
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