CN102923923A - Method for reducing nitric oxides by using disposed sludge - Google Patents
Method for reducing nitric oxides by using disposed sludge Download PDFInfo
- Publication number
- CN102923923A CN102923923A CN2012103846431A CN201210384643A CN102923923A CN 102923923 A CN102923923 A CN 102923923A CN 2012103846431 A CN2012103846431 A CN 2012103846431A CN 201210384643 A CN201210384643 A CN 201210384643A CN 102923923 A CN102923923 A CN 102923923A
- Authority
- CN
- China
- Prior art keywords
- sludge
- mud
- utilizing
- disposing
- oxynitride
- 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
Images
Landscapes
- Treatment Of Sludge (AREA)
Abstract
The invention relates to a method for reducing nitric oxides by using disposed sludge. The method comprises the following steps of: conveying domestic sludge from a sewage treatment plant to a plant by using a vehicle, uniformly stirring the domestic sludge in a stirrer, conveying the domestic sludge to a conveying sieving machine, and further scattering large-particle sludge; throwing the scattered sludge out through small holes in the barrel wall of the conveying sieving machine to directly enter into a sludge pond for being disposed, collecting un-scattered sludge and then recycling to enter into the stirrer for being stirred; stirring and mixing the sludge entering into the sludge pond for the second time, directly throwing into a sludge spray gun through a sludge pump, and throwing wet sludge into a kiln tail decomposition furnace for incineration through a scattering function of the spray gun. The method has the advantages that a reducing atmosphere is formed in a cement kiln decomposition furnace while sludge is disposed by using ammonia nitrogen in the sludge, most of nitric oxides can be directly reduced into nitrogen, thus the nitric oxides in the tail gas of a cement kiln can be reduced, and the disposition amount of the sludge is increased.
Description
Technical field
The present invention relates to a kind of method of disposing sludge, be specifically related to a kind of method of utilizing disposing sludge to reduce the oxynitride in the cement kiln tail gas.
Background technology
Oxynitride mainly is with nitrogen protoxide and the coexistence of nitrogen peroxide balance in atmosphere.Oxynitride can cause the various respiratory tract disease, is the principal pollutant that form photo-chemical smog, also is one of main acidic substance that form acid rain.Sulfurous gas and oxynitride can also form the fine particle of inorganic salt, increase the weight of airborne fine particle and pollute.And cement production enterprise has become the thermal power generation that continues, the third-largest discharged nitrous oxides rich and influential family after the vehicle exhaust.At present, China has nearly 5000 of cement production enterprise, and output occupies first place, the world for years.Whole nation accumulative total cement total output was 18.7 hundred million tons in 2010, and 2,070,000 tons of discharging oxynitride account for 17% of national industrial discharge total amount, and control and improvement nitrogen oxides pollution are extremely urgent.
According to the relevant regulations of GB4915-2004, the cement production enterprise oxynitride is (with NO
2Meter), be limited to 800mg/m on the emission concentration
2(mark).The new dry process rotary kiln discharged nitrous oxides concentration of present domestic operation still lacks the statistic data of system, shows according to some incomplete monitoring data, greatly about 800mg/Nm
3～1600mg/Nm
3About.
In China's new type nonaqueous cement rotary kiln oxynitride control techniques commonly used: the one, optimize the combustion system of kiln and decomposing furnace; The 2nd, change proportion scheme, mix mineralizer in the hope of reducing grog firing temperature and time, improve the grog burn-ability; The 3rd, adopt low NO; The 4th, in kiln tail decomposing furnace and ducted stage burning technology.Service condition from present China Cement industry oxynitride control techniques, except some cement kilns have adopted the low NO design, and the part new type dry kiln is not taked any measure of control substantially by outside the control decomposing furnace generation reducing atmosphere reduction discharged nitrous oxides.
Along with country formally brings the reduction of oxynitride into schedule, once before this expression of the relevant responsible official of Environmental Protection Department will be carried out the oxynitride overall control to cement industry.In future, Environmental Protection Department will be the precondition of oxynitride as the approval new project, and new project must be installed efficient denitrifying device; Carrying out on a large scale the cement produced with the dry method denitration transforms.For encouraging enterprise's denitration, in line with the principle of breakeven and meagre profit, Environmental Protection Department will be put into effect the preferential electrovalence policy of denitration together with relevant department, carry out the energy-saving and emission-reduction power generation dispatching.
Domestic and international application and some flue gas nitrogen oxides of researching and developing remove technology, comprising selective catalytic reduction, selective non-catalytic reduction method, plasma-activated method, biological process and microwave method etc., low NOx combusting technology mainly comprises: optimize the combustion system of kiln and decomposing furnace, keep the stable of kiln system operation; Change proportion scheme, mix mineralizer and reduce grog firing temperature and time, improve burnability of raw material; Adopt the sophisticated equipments such as low-NOx combustor, low NOx decomposing furnace; In technology such as kiln tail decomposing furnace and ducted stage burning technology.That application is more at present is selective catalytic reduction (SCR), selective non-catalytic reduction method (SNCR), low-NOx combustor, decomposing furnace grading combustion technology.Electron beam or corona discharge method cost are higher, and biological process, microwave method etc. is in experimental stage, but prospect is more wide.
SCR (SCR) is to realize the earliest the removal of nitrogen oxide technology of industrial applications, the strict control of its process NH
3/ NO ratio.SCR denitrogenation principle is to utilize NH
3And catalyzer (basic metal such as iron, vanadium, chromium, cobalt or molybdenum) is reduced to N with NOx when temperature is 200～450 ℃
2NH
3Have selectivity, only react with NOx, basically not with O
2Reaction is so be called the SCR denitrogenation.The denitrification percent of SCR technology can reach more than 90%.This technology has reached more than 500 (comprising power station and other industrial sectors) at present in coal-burning power plant's widespread use of the countries such as Japan, Germany, Northern Europe at present.Germany introduces the SCR technology the eighties in 20th century, and the above power plant of regulation generated energy 50MW must be equipped with the SCR system, and SCR accounts for greatly 95% in the flue gas denitrification device in its fuel-burning power plant.
Compare with the SCR method, selective non-catalytic reduction method (SNCR) is except without the catalyzer, and ultimate principle and chemical reaction are basic identical.Ammonia free radical and the NOx reaction of SNCR method by producing in stack gas is to remove NOx.Because there not being catalyst action, react temperature required higher (900～1200 ℃), temperature control is crucial, in order to avoid ammonia is oxidized to oxynitride.The advantage of this method is not need catalyzer, and investment is than little (15 dollars of the investment costs/Kw) of SCR method.But the ammoniacal liquor consumption is large, and the decreasing ratio of NOx is not high yet.Day, this part power plant adopted the SNCR method.But present most of boiler does not adopt this method, and major cause is: efficient is not high, the consumption of reagent and carrying agent is large, spillage ammonia reaches greatly (the NH of generation
4)
2SO
4And NH
4HSO
4Can Corrosion blockage equipment.
Along with the development of new type nonaqueous cement technology and the raising of environmental protection standard, SNCR and SCR denitration will become mainstream technology, and the SCR denitration technology can guarantee that the waste gas nitrous oxides concentration drops to 100mg/Nm
3～200mg/Nm
3, the emission reduction effect of nitrogen peroxide is up to 85%～95%, and its reduction performance can not be subject to the impact that the cement kiln specification maximizes as SNCR.But SCR need to use and consume expensive noble metal catalyst, and because the dust concentration of cement production enterprise waste gas is very high, alkali metal content is higher, easily makes poisoning of catalyst and obstruction.At present, this technology has just begun to put into practice in Cement industry, also has larger room for improvement.The denitration efficiency of SNCR method is 50%～60%, is lower than the denitration efficiency (80%～90%) of selective catalytic reduction (SCR), and the expense of SNCR method (comprising cost of equipment and process cost) only has about 1/5 of SCR method.But the SNCR technology is used the unsettled problems such as nitric efficiency is fluctuated that exist at different device.
Summary of the invention
With not enough, in view of present spray ammonia the high working cost of nitrogen falls based on the problems referred to above again, and the immense pressure of following oxynitride reduction of discharging, be necessary to try new effective scheme and fall nitrogen.The object of the present invention is to provide a kind of method of utilizing disposing sludge to reduce oxynitride, it adopts the wet mud of the direct torch firing of cement kiln decomposing furnace, utilize the ammonia nitrogen in the mud, in disposing sludge, make in the cement kiln decomposing furnace and form reducing atmosphere, can directly most reduction of nitrogen oxide be become nitrogen, not only can reduce discharged nitrous oxides in the cement kiln tail gas, it is high to have solved simultaneously the sludge drying working cost, the present situation that heat energy utilization is not high, not only reduce the cost of sludge disposal, can also increase the disposal of sludge amount.
The objective of the invention is to realize that by following technical scheme it may further comprise the steps:
(1) after transporting in the factory by vehicle the domestic sludge of sewage work, enters into agitator and stir;
(2) sludge agitation evenly after, be transported in the transport bolting mill, further oarse-grained mud is broken up;
(3) the macrobead mud after breaing up throws away (because effect of centrifugal force) by the aperture of transport bolting mill bucket wall, directly enter into sludge sump and dispose, after the mud of failing to break up then is collected again circulation enter into agitator and stir;
(4) mud that enters into sludge sump carries out the secondary stirring mixing in sludge sump, and suitably adds waste liquid according to the denseness of mud and regulate;
(5) mud that again stirs directly is driven in the mud spray gun by the sludge pump of sludge sump bottom;
(6) be driven into the cement kiln end decomposing furnace and burn by the effect of breaing up of the spray gun mud that will wet.
Owing to contain some ammonia nitrogen in the mud, this part can be directly and the oxynitride generation nitrogen that reacts, (make coal anoxic when burning greatly owing to consume oxygen content in the process that the wet mud that sprays into simultaneously burns in kiln, form carbon monoxide), can in decomposing furnace, forming reducing atmosphere, and the reducing atmosphere that should the zone forms can directly become nitrogen with most reduction of nitrogen oxide.
Regression equation is as follows:
(x+2)NH
4 ++2NOx+2O
2→(2+x/2)N
2+2(x+2)H
2O
2C+O
2→2CO
2xCO+2NOx→N
2+2xCO
2
Fall by this method nitrogen, common one ton of mud can reduce oxynitride 47ppm, but one day disposing sludge 20-50 ton.
In the described step (1), the water ratio of the domestic sludge of sewage work is about 80%; In the described step (4), suitably add waste liquid according to the denseness of mud and regulate, make the water ratio of mud reach 85～90%, must guarantee that the mud of ejection is in fluidized state.
The spray mud amount of described sludge pump is 2～4 tons/hour.
Because wet mud is driven into the cement kiln end decomposing furnace and burns, decomposing furnace need replenish Coal-fired capacity, can stablize the temperature fluctuation in the decomposing furnace, and the temperature general control in the decomposing furnace is at 880 ± 20 ℃.
Described transport bolting mill is a roller grizzly separating device that is similar to roller washing machine, can further oarse-grained mud be broken up by this equipment; Transport bolting mill bucket wall is provided with many row's apertures, and the aperture of the macrobead mud after breaing up by transport bolting mill bucket wall (owing to the effect of centrifugal force throws away mud granule from bucket wall aperture) directly enters into sludge sump and dispose.
Be provided with agitator in the middle of the described sludge sump, make the mud that enters into sludge sump in sludge sump, can carry out secondary stirring and mix.
The invention has the beneficial effects as follows:
1, utilizes ammonia nitrogen in the mud, in disposing sludge, make in the cement kiln decomposing furnace and form reducing atmosphere, can directly most reduction of nitrogen oxide be become nitrogen, thereby reduce discharged nitrous oxides in the cement kiln tail gas.
2, selective non-catalytic reduction and grading combustion technology are integrated, reached disposing sludge when subduing oxynitride.
3, it is high to have solved the sludge drying working cost, and the present situation that heat energy utilization is not high has not only reduced the cost of sludge disposal, has also increased the disposal of sludge amount; Will in cement industry, open a kind of new Mode of Circular.
Description of drawings
Accompanying drawing is to utilize disposing sludge to reduce the process flow sheet of the method for oxynitride.
Embodiment
A kind of embodiment that utilizes disposing sludge to reduce the method for oxynitride of the present invention, as shown in drawings, it may further comprise the steps:
(1) after transporting in the factory by vehicle the domestic sludge of sewage work, enters into agitator and stir;
(2) sludge agitation evenly after, be transported in the transport bolting mill, further oarse-grained mud is broken up;
(3) the macrobead mud after breaing up throws away (because effect of centrifugal force) by the aperture of transport bolting mill bucket wall, directly enter into sludge sump and dispose, after the mud of failing to break up then is collected again circulation enter into agitator and stir;
(4) mud that enters into sludge sump carries out the secondary stirring mixing in sludge sump, and suitably adds waste liquid according to the denseness of mud and regulate;
(5) mud that again stirs directly is driven in the mud spray gun by the sludge pump of sludge sump bottom;
(6) be driven into the cement kiln end decomposing furnace and burn by the effect of breaing up of the spray gun mud that will wet.
In the described step (1), the water ratio of the domestic sludge of sewage work is about 80%; In the present embodiment, the water ratio of domestic sludge is 80%.
In the described step (4), suitably add waste liquid according to the denseness of mud and regulate, make the water ratio of mud reach 85～90%, must guarantee that the mud of ejection is in fluidized state.
The spray mud amount of described sludge pump is 2～4 tons/hour, and in the present embodiment, the spray mud amount of sludge pump is 3 tons/hour.
Because wet mud is driven into the cement kiln end decomposing furnace and burns, decomposing furnace need replenish Coal-fired capacity, can stablize the temperature fluctuation in the decomposing furnace, and the temperature general control in the decomposing furnace is at 880 ± 20 ℃.In the present embodiment, the temperature in the decomposing furnace is controlled at 880 ℃.
Described transport bolting mill is a roller grizzly separating device that is similar to roller washing machine, can further oarse-grained mud be broken up by this equipment; Transport bolting mill bucket wall is provided with many row's apertures, and the macrobead mud after breaing up throws away by the aperture of transport bolting mill bucket wall.
Be provided with agitator in the middle of the described sludge sump, make the mud that enters into sludge sump in sludge sump, can carry out secondary stirring and mix.
Claims (6)
1. method of utilizing disposing sludge to reduce oxynitride, it is characterized in that: it may further comprise the steps:
(1) after transporting in the factory by vehicle the domestic sludge of sewage work, enters into agitator and stir;
(2) sludge agitation evenly after, be transported in the transport bolting mill, further oarse-grained mud is broken up;
(3) the macrobead mud after breaing up throws away by the aperture of transport bolting mill bucket wall, directly enter into sludge sump and dispose, after the mud of failing to break up then is collected again circulation enter into agitator and stir;
(4) mud that enters into sludge sump carries out the secondary stirring mixing in sludge sump, and suitably adds waste liquid according to the denseness of mud and regulate;
(5) mud that again stirs directly is driven in the mud spray gun by the sludge pump of sludge sump bottom;
(6) be driven into the cement kiln end decomposing furnace and burn by the effect of breaing up of the spray gun mud that will wet.
2. the method for utilizing disposing sludge to reduce oxynitride as claimed in claim 1, it is characterized in that: in the described step (4), suitably add waste liquid according to the denseness of mud and regulate, make the water ratio of mud reach 85～90%, guarantee that the mud of ejection is in fluidized state.
3. the method for utilizing disposing sludge to reduce oxynitride as claimed in claim 1, it is characterized in that: the spray mud amount of described sludge pump is 2～4 tons/hour.
4. the method for utilizing disposing sludge to reduce oxynitride as claimed in claim 1 is characterized in that: the temperature general control in the described decomposing furnace is at 880 ± 20 ℃.
5. the method for utilizing disposing sludge to reduce oxynitride as claimed in claim 1, it is characterized in that: described transport bolting mill is a roller grizzly separating device that is similar to roller washing machine, can further oarse-grained mud be broken up by this equipment; Transport bolting mill bucket wall is provided with many row's apertures, and the macrobead mud after breaing up throws away by the aperture of transport bolting mill bucket wall.
6. the method for utilizing disposing sludge to reduce oxynitride as claimed in claim 1 is characterized in that: be provided with agitator in the middle of the described sludge sump, make the mud that enters into sludge sump carry out secondary stirring in sludge sump and mix.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012103846431A CN102923923A (en) | 2012-10-12 | 2012-10-12 | Method for reducing nitric oxides by using disposed sludge |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012103846431A CN102923923A (en) | 2012-10-12 | 2012-10-12 | Method for reducing nitric oxides by using disposed sludge |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102923923A true CN102923923A (en) | 2013-02-13 |
Family
ID=47638887
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012103846431A Pending CN102923923A (en) | 2012-10-12 | 2012-10-12 | Method for reducing nitric oxides by using disposed sludge |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102923923A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103301733A (en) * | 2013-07-02 | 2013-09-18 | 中国环境科学研究院 | Method and device for removing oxynitride in smoke by organic waste |
| CN110410800A (en) * | 2019-07-31 | 2019-11-05 | 王天陆 | A method of processing powder class and sludge class waste are cooperateed with using cement kiln |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0417705A1 (en) * | 1989-09-11 | 1991-03-20 | Onoda Cement Company, Ltd. | Method and system for aqueous sewage sludge disposal |
| US5217624A (en) * | 1989-09-11 | 1993-06-08 | Onoda Cement Co., Ltd. | Method for the disposal of aqueous sewage sludge |
| WO1995025075A1 (en) * | 1994-03-16 | 1995-09-21 | Cement Industry Environmental Consortium | Method and system for controlling pollutant emissions in combustion operations |
| CN1669961A (en) * | 2005-03-14 | 2005-09-21 | 常州市排水管理处 | Sludge burning treatment method and system |
| CN101886811A (en) * | 2010-05-21 | 2010-11-17 | 尹小林 | Method for coprocessing sludge with high moisture content by novel dry-process rotary kiln |
| CN201768677U (en) * | 2010-09-07 | 2011-03-23 | 陈瑞 | Cylindrical material sieving machine |
| CN102211887A (en) * | 2011-03-21 | 2011-10-12 | 广州市越堡水泥有限公司 | Cement production method for efficient nitrogen reduction and denitration |
-
2012
- 2012-10-12 CN CN2012103846431A patent/CN102923923A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0417705A1 (en) * | 1989-09-11 | 1991-03-20 | Onoda Cement Company, Ltd. | Method and system for aqueous sewage sludge disposal |
| US5217624A (en) * | 1989-09-11 | 1993-06-08 | Onoda Cement Co., Ltd. | Method for the disposal of aqueous sewage sludge |
| WO1995025075A1 (en) * | 1994-03-16 | 1995-09-21 | Cement Industry Environmental Consortium | Method and system for controlling pollutant emissions in combustion operations |
| CN1669961A (en) * | 2005-03-14 | 2005-09-21 | 常州市排水管理处 | Sludge burning treatment method and system |
| CN101886811A (en) * | 2010-05-21 | 2010-11-17 | 尹小林 | Method for coprocessing sludge with high moisture content by novel dry-process rotary kiln |
| CN201768677U (en) * | 2010-09-07 | 2011-03-23 | 陈瑞 | Cylindrical material sieving machine |
| CN102211887A (en) * | 2011-03-21 | 2011-10-12 | 广州市越堡水泥有限公司 | Cement production method for efficient nitrogen reduction and denitration |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103301733A (en) * | 2013-07-02 | 2013-09-18 | 中国环境科学研究院 | Method and device for removing oxynitride in smoke by organic waste |
| CN103301733B (en) * | 2013-07-02 | 2015-05-13 | 中国环境科学研究院 | Method and device for removing oxynitride in smoke by organic waste |
| CN110410800A (en) * | 2019-07-31 | 2019-11-05 | 王天陆 | A method of processing powder class and sludge class waste are cooperateed with using cement kiln |
| CN110410800B (en) * | 2019-07-31 | 2022-12-09 | 王天陆 | Method for cooperatively treating powder and sludge wastes by using cement kiln |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10092877B1 (en) | Dust removal and desulfurization of FCC exhaust gas | |
| CN105344236A (en) | An integrated desulfurization-denitrification-dedusting process for coke oven flue gas | |
| CN110756033A (en) | Deep purification treatment system and process for waste incineration power station flue gas | |
| CN205145971U (en) | Coke oven flue gas desulfurization denitration dust removal integration system | |
| CN102600709B (en) | Method and device for flue gas desulfurization and denitration by combination of ozone and alkali wastewater | |
| CN106731560B (en) | A kind of house refuse cooperates with power generation by waste combustion waste gas purification minimum discharge system with sludge | |
| CN102015070A (en) | System for treating discharge gas and method of removing mercury from discharge gas | |
| CN111841322B (en) | Denitration and discharge method for cement kiln | |
| CN102188897A (en) | Wet flue gas desulfurization and denitrification combined method | |
| CN110052141A (en) | The desulphurization denitration dedusting minimum discharge technique and system of sour feedstock production cement | |
| EP1786541A1 (en) | Method and system for reducing ammonia slip after selective reduction of nox | |
| CN111499348A (en) | Production process of sintered brick | |
| CN105032137A (en) | Quick lime-ammonia water combined flue gas desulfurization and denitrification integrated apparatus | |
| CN102120139B (en) | Wet type combined desulfuration and denitration device and method for coal-fired boiler | |
| CN102188889B (en) | Device and method for combined removal of sulphur dioxide (SO2), nitrogen oxide (NOX) and mercury from fume | |
| CN109592647B (en) | Process for preparing sulfur and recovering desulfurizing/nitre agent by sulfur/nitrate iron-carbon reduction | |
| Zhu et al. | The simultaneous removal of NOx and SO2 from flue gas by direct injection of sorbents in furnace of waste incinerator | |
| CN214552547U (en) | Front-mounted cement kiln high-temperature high-dust flue gas SCR denitration device | |
| CN204352726U (en) | Water coal-pulp smoke cleaning system | |
| CN102923923A (en) | Method for reducing nitric oxides by using disposed sludge | |
| CN104474887B (en) | Dry-process cement rotary kiln desulphurization denitration complexing agent method of preparation and use | |
| CN206762618U (en) | A kind of dry-wet integratedization desulfuring and denitrifying apparatus | |
| CN109316941A (en) | The equipment for denitrifying flue gas and its method of denitration of ozone combination urea combination SNCR | |
| CN103623682A (en) | HC-LSCR/O-AS engineering system for fume cleaning | |
| CN103170229A (en) | Desulfurization and denitration integrated system of industrial kiln stove |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20130213 |
|
| RJ01 | Rejection of invention patent application after publication |