CN112784405A - Boiler slagging prediction method based on numerical simulation and related device - Google Patents
Boiler slagging prediction method based on numerical simulation and related device Download PDFInfo
- Publication number
- CN112784405A CN112784405A CN202110012774.6A CN202110012774A CN112784405A CN 112784405 A CN112784405 A CN 112784405A CN 202110012774 A CN202110012774 A CN 202110012774A CN 112784405 A CN112784405 A CN 112784405A
- Authority
- CN
- China
- Prior art keywords
- slagging
- boiler
- condition
- model
- heating surface
- 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.)
- Granted
Links
- 238000004088 simulation Methods 0.000 title claims abstract description 139
- 238000000034 method Methods 0.000 title claims abstract description 73
- 238000010438 heat treatment Methods 0.000 claims abstract description 105
- 238000002485 combustion reaction Methods 0.000 claims abstract description 95
- 239000002245 particle Substances 0.000 claims abstract description 82
- 239000003245 coal Substances 0.000 claims abstract description 73
- 230000008878 coupling Effects 0.000 claims abstract description 39
- 238000010168 coupling process Methods 0.000 claims abstract description 39
- 238000005859 coupling reaction Methods 0.000 claims abstract description 39
- 238000003860 storage Methods 0.000 claims abstract description 9
- 239000010883 coal ash Substances 0.000 claims description 30
- 238000009826 distribution Methods 0.000 claims description 12
- 239000004071 soot Substances 0.000 claims description 12
- 238000004590 computer program Methods 0.000 claims description 10
- 239000000126 substance Substances 0.000 claims description 9
- 238000012937 correction Methods 0.000 claims description 7
- 230000006641 stabilisation Effects 0.000 claims description 3
- 238000011105 stabilization Methods 0.000 claims description 3
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 239000002893 slag Substances 0.000 description 52
- 239000002956 ash Substances 0.000 description 43
- 230000008018 melting Effects 0.000 description 34
- 238000002844 melting Methods 0.000 description 34
- 230000008021 deposition Effects 0.000 description 16
- 239000010881 fly ash Substances 0.000 description 13
- 230000008569 process Effects 0.000 description 13
- 230000008859 change Effects 0.000 description 12
- 230000000694 effects Effects 0.000 description 10
- 230000015572 biosynthetic process Effects 0.000 description 9
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical compound [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 9
- 239000002817 coal dust Substances 0.000 description 8
- 239000007789 gas Substances 0.000 description 8
- 238000012546 transfer Methods 0.000 description 8
- 239000000843 powder Substances 0.000 description 7
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 6
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 6
- 239000013078 crystal Substances 0.000 description 6
- 239000000203 mixture Substances 0.000 description 6
- 229910052760 oxygen Inorganic materials 0.000 description 6
- 239000001301 oxygen Substances 0.000 description 6
- 229910052710 silicon Inorganic materials 0.000 description 6
- 239000010703 silicon Substances 0.000 description 6
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 6
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 5
- 238000009825 accumulation Methods 0.000 description 5
- 229910000323 aluminium silicate Inorganic materials 0.000 description 5
- 238000004364 calculation method Methods 0.000 description 5
- 229910052681 coesite Inorganic materials 0.000 description 5
- 229910052906 cristobalite Inorganic materials 0.000 description 5
- HNPSIPDUKPIQMN-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Al]O[Al]=O HNPSIPDUKPIQMN-UHFFFAOYSA-N 0.000 description 5
- 239000000428 dust Substances 0.000 description 5
- 239000000155 melt Substances 0.000 description 5
- 229910052682 stishovite Inorganic materials 0.000 description 5
- 229910052905 tridymite Inorganic materials 0.000 description 5
- 239000002253 acid Substances 0.000 description 4
- 230000002378 acidificating effect Effects 0.000 description 4
- 230000009471 action Effects 0.000 description 4
- 238000005260 corrosion Methods 0.000 description 4
- 230000007797 corrosion Effects 0.000 description 4
- 238000013461 design Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 230000005484 gravity Effects 0.000 description 4
- 230000000704 physical effect Effects 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 229910018557 Si O Inorganic materials 0.000 description 3
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 3
- 230000002411 adverse Effects 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000012530 fluid Substances 0.000 description 3
- 239000000446 fuel Substances 0.000 description 3
- 229910052500 inorganic mineral Inorganic materials 0.000 description 3
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000011707 mineral Substances 0.000 description 3
- 238000006116 polymerization reaction Methods 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 239000003238 silicate melt Substances 0.000 description 3
- 239000000377 silicon dioxide Substances 0.000 description 3
- 239000011593 sulfur Substances 0.000 description 3
- 229910052717 sulfur Inorganic materials 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- KKCBUQHMOMHUOY-UHFFFAOYSA-N Na2O Inorganic materials [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 2
- 229910000272 alkali metal oxide Inorganic materials 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 125000000129 anionic group Chemical group 0.000 description 2
- 238000004422 calculation algorithm Methods 0.000 description 2
- 150000001768 cations Chemical class 0.000 description 2
- 238000004939 coking Methods 0.000 description 2
- 229910052593 corundum Inorganic materials 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 230000006870 function Effects 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000012804 iterative process Methods 0.000 description 2
- 239000007791 liquid phase Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 239000013049 sediment Substances 0.000 description 2
- 239000000779 smoke Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 229910001845 yogo sapphire Inorganic materials 0.000 description 2
- 239000005995 Aluminium silicate Substances 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 229910002808 Si–O–Si Inorganic materials 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000001339 alkali metal compounds Chemical class 0.000 description 1
- 229910052936 alkali metal sulfate Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 235000012211 aluminium silicate Nutrition 0.000 description 1
- 229910052661 anorthite Inorganic materials 0.000 description 1
- 230000006399 behavior Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 239000002802 bituminous coal Substances 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 239000010884 boiler slag Substances 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 239000002734 clay mineral Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- GWWPLLOVYSCJIO-UHFFFAOYSA-N dialuminum;calcium;disilicate Chemical compound [Al+3].[Al+3].[Ca+2].[O-][Si]([O-])([O-])[O-].[O-][Si]([O-])([O-])[O-] GWWPLLOVYSCJIO-UHFFFAOYSA-N 0.000 description 1
- 230000005496 eutectics Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 229910001678 gehlenite Inorganic materials 0.000 description 1
- 229910052900 illite Inorganic materials 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- VGIBGUSAECPPNB-UHFFFAOYSA-L nonaaluminum;magnesium;tripotassium;1,3-dioxido-2,4,5-trioxa-1,3-disilabicyclo[1.1.1]pentane;iron(2+);oxygen(2-);fluoride;hydroxide Chemical compound [OH-].[O-2].[O-2].[O-2].[O-2].[O-2].[F-].[Mg+2].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[Al+3].[K+].[K+].[K+].[Fe+2].O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2.O1[Si]2([O-])O[Si]1([O-])O2 VGIBGUSAECPPNB-UHFFFAOYSA-L 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 238000000611 regression analysis Methods 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 150000004760 silicates Chemical class 0.000 description 1
- 229910052851 sillimanite Inorganic materials 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 230000008719 thickening Effects 0.000 description 1
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N titanium dioxide Inorganic materials O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
- G06F30/28—Design optimisation, verification or simulation using fluid dynamics, e.g. using Navier-Stokes equations or computational fluid dynamics [CFD]
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2111/00—Details relating to CAD techniques
- G06F2111/10—Numerical modelling
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Evolutionary Computation (AREA)
- Geometry (AREA)
- General Engineering & Computer Science (AREA)
- Algebra (AREA)
- Computing Systems (AREA)
- Fluid Mechanics (AREA)
- Mathematical Analysis (AREA)
- Mathematical Optimization (AREA)
- Mathematical Physics (AREA)
- Pure & Applied Mathematics (AREA)
- Regulation And Control Of Combustion (AREA)
Abstract
The invention discloses a boiler slagging prediction method based on numerical simulation, which comprises the steps of coupling a preset slagging model with a combustion model corresponding to a boiler combustion numerical simulation database to obtain a coupling model; calculating an initial slagging condition based on the coupling model and data in a boiler combustion numerical simulation database; calculating the slagging growth condition based on the initial slagging condition and a preset slagging growth model; the slagging growth model is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler; after the initial slagging condition is obtained through the slagging model based on the limiting condition of the combustion model, the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler is corrected based on the slagging growth model and iteration is performed, so that the simulated slagging growth condition is ensured to be more in line with the actual condition. The invention also provides a device, equipment and a storage medium, which also have the beneficial effects.
Description
Technical Field
The invention relates to the technical field of boilers, in particular to a boiler slagging prediction method based on numerical simulation, a boiler slagging prediction device based on numerical simulation, boiler slagging prediction equipment based on numerical simulation and a computer-readable storage medium.
Background
The heating surface of the boiler has more or less slagging and dust accumulation phenomena, and the influence of normal slagging and dust accumulation on the operation of the boiler is generally considered when the heating surface of the boiler is designed. The national conditions determine that most of power station boilers in China mainly use fire coal, and the existing power coal has general deviation of coal quality, higher ash and sulfur content and easy deposition on a heating surface. According to statistics, about 50% of coal used by large coal-fired units in China belongs to easy-to-slag coal, and in recent years, some power production enterprises achieve the purposes of saving power generation cost and pursuing greater economic benefit by burning coal with lower grade, high ash content, low ash melting point and lower price, so that the quality of coal for boiler combustion deviates from the original design value, the slag and ash accumulation condition of a heating surface is increased undoubtedly, and adverse effects are caused on the economy and safe operation of a boiler.
The slagging and ash deposition of the convection heating surface have a plurality of adverse effects on the economic and safe operation of the coal-fired unit, and are mainly reflected in the following aspects: first, the effect on heat transfer is the first. Because the heat conductivity coefficient of the sediment is far less than the heat conductivity coefficient of the pipe wall, the heat exchange coefficient of steam and the like, the heat resistance generated by the sediment is dominant in the total heat resistance, if the deposited ash can not be removed in time, the heat transfer efficiency of the boiler can be greatly influenced, the exhaust gas temperature of the boiler is increased, and the efficiency of the boiler is reduced. Secondly, slagging and ash deposition inevitably cause corrosion and abrasion of the metal on the heating surface. Sulfur, chlorine, alkali metals, and other elements in the coal can cause ash deposition and corrosion on the heated surface. Alkali metal compounds sublime at high temperatures and then condense on the lower temperature walls of the tubes, forming complex low melting point compounds, often in the liquid phase, known as a melt pool. The alkali metal sulfate in the molten bath and the pipe wall metal undergo complex chemical reaction to form sulfate high-temperature corrosion, which can cause the pipe wall metal to be rapidly thinned and affect the service life of the pipe. Thirdly, serious dust accumulation and slag bonding can even cause serious operation accidents, equipment is damaged to influence production, and casualties and crisis safety are caused seriously. Excessive dust accumulation and ineffective removal can cause dust blockage in the flue, increase the ventilation resistance and reduce the boiler output. And the high-temperature corrosion of the pipe wall can cause the local high temperature and abrasion of the pipe wall to possibly cause pipe explosion accidents, thus harming the safe production.
At present, the accuracy of a prediction method for the boiler slagging condition is low, so that how to provide a prediction method with high accuracy is a problem which needs to be solved urgently by a person skilled in the art.
Disclosure of Invention
The invention aims to provide a boiler slagging prediction method based on numerical simulation, which has higher accuracy; it is another object of the present invention to provide a boiler slagging prediction apparatus based on numerical simulation, and a computer-readable storage medium, which have high accuracy.
In order to solve the technical problem, the invention provides a boiler slagging prediction method based on numerical simulation, which comprises the following steps:
calling a boiler combustion numerical simulation database;
coupling a preset slagging model with a combustion model corresponding to the boiler combustion numerical simulation database to obtain a coupling model;
calculating an initial slagging condition based on the coupling model and data in the boiler combustion numerical simulation database;
calculating the slagging growth condition based on the initial slagging condition and a preset slagging growth model; the slagging growth model is an iterative model of the slagging model, and is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler;
and when the slagging growth condition shows that the slagging of the heating surface of the boiler is stable, calculating relevant parameters of the heating surface of the boiler by taking the condition of the heating surface of the boiler with stable slagging as a combustion simulation boundary condition.
Optionally, the slagging model is used for calculating the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler;
the calculating of the slagging growth condition based on the initial slagging condition and a preset slagging growth model comprises:
correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler based on the current slagging condition through a slagging growth model;
and calculating the current slagging condition according to the corrected adhesion probability, and circularly executing the step of correcting the adhesion probability of the current pulverized coal particles adhering to the heating surface of the boiler based on the current slagging condition through the slagging growth model until the current slagging condition is calculated according to the corrected adhesion probability until the slagging of the heating surface of the boiler is stable.
Optionally, the attachment probability of the current pulverized coal particles attaching to the heated surface of the boiler is the product of the coal ash attachment probability, the incidence angle influence coefficient and the incidence speed influence coefficient.
Optionally, the correcting, by the slagging growth model, the attachment probability of the current pulverized coal particles to the heating surface of the boiler based on the current slagging condition includes:
correcting the wall surface condition of the heating surface of the boiler and the temperature of coal ash according to the current slagging condition of the heating surface of the boiler;
determining a corrected adhesion probability based on the corrected wall surface condition and the soot temperature.
Optionally, the relevant parameters of the heated surface of the boiler include any one or any combination of the following:
the heat exchange condition of the heating surface of the boiler, the velocity field in the boiler, the temperature field in the boiler, the particle concentration distribution field in the boiler and the gas substance concentration distribution field in the boiler.
Optionally, the boiler combustion numerical simulation database is a CFD simulation database.
The invention also provides a boiler slagging prediction device based on numerical simulation, which comprises:
a calling module: the simulation database is used for calling a boiler combustion numerical value;
a coupling module: the boiler combustion numerical simulation system is used for coupling a preset slagging model with a combustion model corresponding to the boiler combustion numerical simulation database to obtain a coupling model;
an initial slagging module: for calculating an initial slagging condition based on the coupling model and data in the boiler combustion numerical simulation database;
a slagging and growing module: the system is used for calculating the slagging condition based on the initial slagging condition and a preset slagging growth model; the slagging growth model is an iterative model of the slagging model, and is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler;
a stabilization module: and when the slagging growth condition shows that the slagging of the heating surface of the boiler is stable, the method is used for calculating relevant parameters of the heating surface of the boiler by taking the condition of the heating surface of the boiler with stable slagging as a combustion simulation boundary condition.
Optionally, the slagging model is used for calculating the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler;
the slagging growth module comprises:
a correction unit: the device is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler based on the current slagging condition through the slagging growth model;
an iteration unit: and the method is used for calculating the current slagging condition according to the corrected adhesion probability, and circularly executing the step of correcting the adhesion probability of the current pulverized coal particles adhering to the heating surface of the boiler based on the current slagging condition through the slagging growth model until the current slagging condition is calculated according to the corrected adhesion probability until the slagging of the heating surface of the boiler is stable.
The invention also provides a boiler slagging prediction device based on numerical simulation, which comprises:
a memory: for storing a computer program;
a processor: for implementing the steps of the numerical simulation based boiler slagging prediction method of any one of the above mentioned when executing the computer program.
The invention also provides a computer readable storage medium having stored thereon a computer program which, when being executed by a processor, carries out the steps of the method for boiler slagging prediction based on numerical simulation according to any of the preceding claims.
The invention provides a boiler slagging prediction method based on numerical simulation, which comprises calling a boiler combustion numerical simulation database; coupling a preset slagging model with a combustion model corresponding to a boiler combustion numerical simulation database to obtain a coupling model; calculating an initial slagging condition based on the coupling model and data in a boiler combustion numerical simulation database; calculating the slagging growth condition based on the initial slagging condition and a preset slagging growth model; the slagging growth model is an iterative model of a slagging and slag model, and is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler; and when the slagging growth condition shows that the slagging of the heating surface of the boiler is stable, calculating relevant parameters of the heating surface of the boiler by taking the condition of the heating surface of the boiler with stable slagging as a combustion simulation boundary condition.
After the initial slagging condition is obtained through the slagging model based on the limiting condition of the combustion model, the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler is corrected and iterated based on the iterative model of the slagging model, namely the slagging growth model, so that the simulated slagging growth condition is more in line with the actual condition, and the finally calculated related parameters are more accurate and more in line with the actual condition.
The invention also provides a boiler slagging prediction device based on numerical simulation, boiler slagging prediction equipment based on numerical simulation and a computer readable storage medium, which also have the beneficial effects and are not repeated herein.
Drawings
In order to more clearly illustrate the embodiments or technical solutions of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.
FIG. 1 is a flow chart of a boiler slagging prediction method based on numerical simulation according to an embodiment of the present invention;
FIG. 2 is a flow chart of a specific boiler slagging prediction method based on numerical simulation according to an embodiment of the present invention;
FIG. 3 is a block diagram of a boiler slagging prediction apparatus based on numerical simulation according to an embodiment of the present invention;
fig. 4 is a block diagram of a boiler slagging prediction apparatus based on numerical simulation according to an embodiment of the present invention.
Detailed Description
The core of the invention is to provide a boiler slagging prediction method based on numerical simulation. In the prior art, slagging and ash deposition on a convection heating surface have a plurality of adverse effects on the economy and safe operation of a coal-fired unit, and the accuracy of a prediction method for the slagging condition of a boiler in the prior art is lower.
The boiler slagging prediction method based on numerical simulation provided by the invention comprises the steps of calling a boiler combustion numerical simulation database; coupling a preset slagging model with a combustion model corresponding to a boiler combustion numerical simulation database to obtain a coupling model; calculating an initial slagging condition based on the coupling model and data in a boiler combustion numerical simulation database; calculating the slagging growth condition based on the initial slagging condition and a preset slagging growth model; the slagging growth model is an iterative model of the slagging model and is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler; and when the slagging growth condition shows that the slagging of the heating surface of the boiler is stable, calculating relevant parameters of the heating surface of the boiler by taking the condition of the heating surface of the boiler with stable slagging as a combustion simulation boundary condition.
After the initial slagging condition is obtained through the slagging model based on the limiting condition of the combustion model, the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler is corrected and iterated based on the iterative model of the slagging model, namely the slagging growth model, so that the simulated slagging growth condition is more in line with the actual condition, and the finally calculated related parameters are more accurate and more in line with the actual condition.
In order that those skilled in the art will better understand the disclosure, the invention will be described in further detail with reference to the accompanying drawings and specific embodiments. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, fig. 1 is a flowchart illustrating a boiler slagging prediction method based on numerical simulation according to an embodiment of the present invention.
Referring to fig. 1, in an embodiment of the present invention, a boiler slagging prediction method based on numerical simulation includes:
s101: and calling a boiler combustion numerical simulation database.
In the embodiment of the invention, a boiler combustion numerical simulation database is preset so as to carry out numerical simulation, and the numerical simulation refers to the Computational Fluid Dynamics research on engineering problems and physical problems by a numerical calculation and image display method by means of computer software, mainly CFD (Computational Fluid Dynamics) software, and combining with the concept of limited volume. Typically, the boiler combustion numerical simulation database is the database used in the simulation of the computer software applied in the embodiment of the present invention.
In the following steps, combustion simulation needs to be performed by combining a boiler combustion numerical simulation database, particularly combining a combustion model corresponding to the boiler combustion numerical simulation database, and taking the limiting conditions in the combustion model as the basis. The details of the boiler combustion value simulation database will be described in detail in the following embodiments of the present invention, and will not be described herein.
In an embodiment of the present invention, the boiler combustion numerical simulation database is typically a CFD simulation database for performing CFD data simulation.
S102: and coupling the preset slagging model with a combustion model corresponding to the boiler combustion numerical value simulation database to obtain a coupling model.
In this step, a preset slagging model and a combustion model corresponding to the boiler combustion numerical simulation database are coupled with each other, and the slagging model is usually input into the computer software, so that the slagging model and the combustion model are coupled with each other to obtain a coupled model, that is, combustion simulation is performed by using the limiting conditions in the combustion model as the basis and combining the slagging model. The details of the slagging model will be described in detail in the following embodiments of the present invention, and will not be described herein.
S103: and calculating the initial slagging condition based on the coupling model and the data in the boiler combustion numerical simulation database.
In this step, the initial slagging condition is obtained based on the values set in the boiler combustion value simulation database and the coupling model, that is, when the heating surface of the boiler is not slagging, various parameters of the heating surface of the boiler during initial slagging, such as slagging position, size and other initial slagging conditions, are obtained through the coupling model. The types of the parameters included in the initial slagging condition may be set according to the actual conditions, and are not limited specifically herein.
S104: and calculating the slagging growth condition based on the initial slagging condition and a preset slagging growth model.
In the embodiment of the invention, the slagging growth model is an iterative model of the slagging model, and the slagging growth model is used for correcting the attachment probability of the current pulverized coal particles to the heating surface of the boiler.
The slagging growth model is an iterative model of the slagging model, and the slagging growth model needs continuous iterative calculation in the use process until slagging of the heating surface of the boiler is stable, namely the slagging size, thickness and other dimensions of the heating surface of the boiler are not changed. The slagging growth model is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler, so that the attachment probability of the pulverized coal particles attached to the heating surface of the boiler before the iterative process can be continuously corrected, and finally the slagging growth condition simulated is more practical. The details of the slagging growth model will be described in detail in the following embodiments of the invention, and will not be described herein. Details regarding the above-mentioned correction process are also described in detail in the following embodiments of the invention, and are not described herein again.
S105: and when the slagging growth condition shows that the slagging of the heating surface of the boiler is stable, calculating relevant parameters of the heating surface of the boiler by taking the condition of the heating surface of the boiler with stable slagging as a combustion simulation boundary condition.
In this step, when the slag bonding on the heating surface of the boiler is stable, the condition of the heating surface of the boiler is used as a combustion simulation boundary condition, and the related parameters of the heating surface of the boiler are calculated again to predict the slag bonding on the heating surface of the boiler.
The boundary condition of slagging refers to stable slagging, after the growth is stopped under the original working condition, slag blocks with different positions, areas and thicknesses appear on the original smooth wall surface, at the moment, the boundary condition of the wall surface is changed, the new condition of the wall surface after slagging is stable is taken as the boundary condition for calculating the heat exchange of the actual hearth, and if the heat conductivity coefficient of the slagging part is changed, the slagging size can influence the air flow velocity distribution and the like.
Specifically, the relevant parameters of the heated surface of the boiler include any one or any combination of the following: the heat exchange condition of the heating surface of the boiler, the velocity field in the boiler, the temperature field in the boiler, the particle concentration distribution field in the boiler and the gas substance concentration distribution field in the boiler. In general, all relevant parameters of the heated surface of the boiler are calculated in this step, that is, under the condition of solving the stable slagging condition, the velocity field, the temperature field, the particle concentration distribution field, the gas substance concentration distribution field of the furnace, the heat exchange condition between the furnace and the heated surface, and the like are solved in this step, so as to realize the comprehensive prediction of the heated surface of the boiler. It should be noted that this step is typically performed based on the CFD software described above to calculate the respective parameters.
In the embodiment of the invention, the particles attached to the heating surface of the boiler for slagging are generally coal dust particles, namely coal ash. The manifestation of coal ash is usually expressed in terms of oxides and mainly includes two main classes depending on the ionic potential of the chemical components of the coal ash: acidic oxide SiO2、Al2O3、TiO2Etc. and alkali oxide Na2O、K2O、CaO、Fe2O3MgO, and the like.
In general, basic oxides promote a reduction in ash melting point, whereas acidic oxides have the opposite effect, but the effect of the components on the ash melting temperature is not simply a linear relationship. SiO 22Has a melting point of 1730 ℃ and exists mainly in an amorphous form in the coal ash, and has uncertainty on the influence on the ash melting point, sometimes the ash melting point is increased, and sometimes the fluxing effect is shown. When SiO in coal ash2At increasing levels from 0, the soot generally exhibits a "change from basic to acidic" behavior, and at too high a level, there are not enough oxides to react with the SiO2Bonding, resulting in ash fusion due to high melting SiO2Is increased. Al (Al)2O3The self-body has a firm crystal structure, the melting point is 2050 ℃, the larger the proportion of the self-body in ash slag is, more 'supports' can be correspondingly provided, and the higher the melting point of the coal ash is, the positive correlation is formed between the melting point of the coal ash and the melting point of the ash. The melting point of CaO is 2610 ℃, and the influence of CaO on the melting point of coal ash is two-sided. When the content is lower, the mass fraction is less than that of CaO and other minerals to generate a low-temperature eutectic phenomenon, so that the ash melting point is promoted to be reduced, and the minerals such as silicate or aluminosilicate are generated: anorthite (CaO. Al)2O3·2SiO2) Gehlenite 2 CaO. Al2O3·2SiO2) Sillimanite (3 CaO. SiO)2) And Aluminonite (CaO. Al)2O3) Etc.; when the mass fraction is more than 40%, the ash melting point is increased due to its high melting point. Fe2O3Belongs to a fluxing agent and can easily react with other components. Whether the coal ash is in oxidation orIn a weak reducing atmosphere, the reduction of the ash melting point can be promoted, and the effect is more obvious in a weak reducing state. Alkali metal oxide Na2O、K2O is the best flux, and is the best flux capable of obviously reducing the ash melting point, and can obviously reduce the ash melting point. MgO and CaO have similar properties, and influence rules on the melting point of the coal ash are similar, so that the MgO and the CaO can be considered together; the properties are similar, and the influence rule on the melting point of the coal ash is similar, so that the coal ash can be considered together; TiO 22As acidic oxides, they have been shown to promote increased ash melting points.
Typically, coal ash has high temperature viscosity characteristics. The high-temperature viscosity characteristic means that crystals made of different materials such as coal ash, glass and ceramic can show different high-temperature flow characteristics and temperature relationships when the crystals are in a high-temperature molten state so as to divide the crystals. Along with the reduction of the temperature, the melts of various materials can form three representative slag forms of glass slag, plastic slag and crystallization slag, and the high-temperature viscosity of the slag is an important parameter reflecting the downward flowing form of the slag along the furnace wall under the shearing and carrying effects of gravity and airflow. Similarly, the high-temperature viscosity of the slag is closely related to the components of the coal ash, the temperature Tcv corresponding to the critical viscosity of the slag can be determined according to the components of the coal ash, the slag gradually presents a liquid-solid two-phase state below the temperature, and the type and the position of a soot blower can be selected according to different temperature areas.
At present, an important criterion for judging whether slagging occurs in the combustion process of a coal-fired boiler is ash meltability, and the softening temperature ST of ash is generally used as a main index for measuring whether slagging occurs. The ash contents of different fuels have different compositions and meltability, and the coal with lower ash melting point (ST <1200 ℃) is easy to slag. The ash melting point measured under the actual working condition in the furnace and the laboratory condition has a large difference, and other indexes must be introduced. The currently adopted method comprises silicon ratio, alkali-acid ratio, slagging index, limiting viscosity and the like.
The larger the silicon ratio, the higher the viscosity of the ash, and the less likely it will be slagging. An increase in the iron and calcium content of the ash reduces the silicon ratio and the viscosity of the ash. Generally, the slag bonding is not easy to occur when the silicon ratio is more than 72, and serious slag bonding can occur when the silicon ratio is less than 65.
Coal having a low alkali-acid ratio (B/A) is less likely to suffer from slag formation. For coal used in the solid-tap pulverized coal furnace, the alkali-acid ratio of ash should be as low as possible to 0.5 in order to prevent slagging.
For Fe2O3>The CaO + MgO bituminous coal type ash has the slagging index:
in the formula SdThe sulfur content is the dry basis of the coal. Slag formation index RSSimilar to the ratio of alkali to acid, RSSmall ash has a higher viscosity, usually RS<At 0.6, the possibility of slag bonding is very low; when R isS>At 2, severe slagging occurs.
Also parameters for predicting the tendency to slag formation, e.g. using the melting temperature R of the ashTTo predict:
in the formula HTmaxIs the hemispherical temperature of ash in an oxidizing atmosphere; DTminIs the ash deformation temperature in a reducing atmosphere. RTLess than 1250 has a severe risk of slagging, and more than 1400 has a lower risk of slagging.
The scheme of the furnace design also has obvious relevance to the slagging of the heating surface of the boiler. The heat load of the furnace volume, the heat load of the cross section and the heat load of the burner area all have certain influence on the slagging. When the heat load of the furnace hearth is too large during the design of the boiler or the heat load of the furnace hearth is too high during the actual operation, the temperature level of the furnace hearth or a local area can be improved, and the possibility of slag bonding is increased. The slagging and ash deposition are related to the operation factors such as boiler load, excess air coefficient, coal powder fineness, smoke exhaust temperature and the like.
When the boiler is burning, the difference between the coal type for burning and the designed coal type is large, the boiler load is too high or too low, the fineness and the uniformity of the pulverized coal are thickened, the primary and secondary air speeds are not properly matched with the air quantity, and the slag bonding or burning-out of the outlet of the burner is often caused; the untimely soot blowing and slag removal is also one of the reasons for the boiler slagging.
The higher the boiler load, the higher the furnace center temperature, so that the softening degree of ash is increased, especially when the flame deflects or the burner swings down or up for a long time, the local area heat load is too high, and the ash is easy to bond at the local area. When the air quantity in the furnace is insufficient or the fuel and the air are not sufficiently mixed, a large amount of reducing gas can be generated, the melting point of ash is reduced, and the slagging is intensified.
The boiler slagging prediction method based on numerical simulation provided by the embodiment of the invention comprises the steps of calling a boiler combustion numerical simulation database; coupling a preset slagging model with a combustion model corresponding to a boiler combustion numerical simulation database to obtain a coupling model; calculating an initial slagging condition based on the coupling model and data in a boiler combustion numerical simulation database; calculating the slagging growth condition based on the initial slagging condition and a preset slagging growth model; the slagging growth model is an iterative model of the slagging model and is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler; and when the slagging growth condition shows that the slagging of the heating surface of the boiler is stable, calculating relevant parameters of the heating surface of the boiler by taking the condition of the heating surface of the boiler with stable slagging as a combustion simulation boundary condition.
After the initial slagging condition is obtained through the slagging model based on the limiting condition of the combustion model, the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler is corrected and iterated based on the iterative model of the slagging model, namely the slagging growth model, so that the simulated slagging growth condition is more in line with the actual condition, and the finally calculated related parameters are more accurate and more in line with the actual condition.
The details of the boiler slagging prediction method based on numerical simulation according to the present invention will be described in detail in the following embodiments of the present invention.
Referring to fig. 2, fig. 2 is a flowchart illustrating a boiler slagging prediction method based on numerical simulation according to an embodiment of the present invention.
Referring to fig. 2, in an embodiment of the present invention, a boiler slagging prediction method based on numerical simulation includes:
s201: and calling a boiler combustion numerical simulation database.
This step is substantially the same as S101 in the above embodiment of the present invention, and details have been described in the above embodiment of the present invention, and are not described herein again.
The database mainly contains some background data required by the numerical simulation process, which is necessary for the CFD numerical simulation process. Such as the element analysis and industrial analysis of coal types, the melting characteristic and viscosity-temperature characteristic of coal ash, the functional relationship between the melting characteristic and viscosity-temperature characteristic of coal ash and reducing atmosphere, and the like. The parameters in the boiler combustion numerical simulation database generally include:
ST＝F1(CO)
DT＝F2(CO)
FT＝F3(CO)
wherein ST is the softening temperature of the coal; DT is the deformation temperature of the coal species, FT is the flow temperature of the coal species, and F (CO) represents a functional relationship with the CO concentration of the reducing atmosphere as a variable.
S202: and coupling the preset slagging model with a combustion model corresponding to the boiler combustion numerical value simulation database to obtain a coupling model.
In the embodiment of the invention, the slagging model is specifically used for calculating the attachment probability of the current pulverized coal particles to the heating surface of the boiler so as to obtain the initial slagging condition in the following steps.
In an embodiment of the present invention, the overall boiler slagging prediction method generally includes simulations of processes that are the basis of a slagging model. These simulations typically include: 1. simulating fly ash formation; 2. simulating fly ash conveying; 3. simulating the collision and adhesion of the fly ash to the wall surface; 4. simulating the growth of a slag layer; 5. simulating the characteristics and the strength of a slag layer; 6. simulating heat transfer through a slag layer; 7. simulating the influence of a slag layer on the operation condition; 8. simulation of the influence of slagging on flow. Among them, the simulation of the transportation of fly ash and the simulation of the adhesion of particles to the wall surface are important points in the simulation of slagging.
For the adhesion simulation of fly ash, the minerals in coal are based on clay minerals such as kaolin, illite, and other silicates and aluminosilicates. Thus, the main component of the coal ash melt should also be silicate/aluminosilicate. The viscosity of the silicate/aluminosilicate is determined primarily by two factors: temperature and chemical composition.
Wherein the relationship between temperature and viscosity can be represented by the following formula:
in the above formula, T is the particle temperature; η is the viscosity of the particles at temperature T to equilibrium; A. b is a constant determined by the chemical composition of the particles.
The effect of chemical composition factors on the viscosity of silicate/aluminosilicate is experimentally shown to be that the basic structural unit of a silicate melt is Si-O tetrahedra, as is the crystal. The Si-O tetrahedra are joined by bridging oxygens into anionic structural groups of various shapes, sizes and complexity, which groups constitute the basic structural units of the silicate melt. The melt structure is similar to the crystal structure in local view, but the atoms in the melt are not arranged in a spatially continuous regular array as a whole. The atoms do not fix lattice positions and the position of the anionic group changes continuously with the thermal motion of the atoms. However, at a given temperature, pressure, and composition, the equilibrium structure of the melt is a fixed, reproducible function. In silicate melts, oxygen has three structural states:
1. bridging oxygen, meaning oxygen linking two Si-O tetrahedra with two Si4+Or substituted Si4+Tetra-coordinated cation (Ti)4+，A13+，Fe3+Etc.) are linked, represented by Si-O-Si, or O0。
2. Nonbridging oxygen, which is oxygen linking one silicon to one noncritical cation, is represented by Si-O-Me+Or O-。
3. Free oxygen, expressed as Me+—O—Me+Or O2-. The content ratio and distribution thereof areAn indication of the degree of melt polymerization. In studying the aluminosilicate structure, the number of nonbridging oxygens in each tetrahedron, namely NBO/T, is an important measure of the degree of melt polymerization, and is defined as:
the lower the NBO/T value, the higher the degree of polymerization. Such as a single tetrahedron, i.e. an island silicate, NBO/T ═ 4; chain structure, NBO/T ═ 2; a mat structure, NBO/T ═ 1; three-dimensional network structure, NBO/T ═ 0.
Specifically, the parameter B can be obtained by multiple regression analysis and experimental observation, the parameter A can be calculated by the parameter B and NBO/T, and finally the parameter A and the parameter B are substituted to calculate the viscosity of the fly ash particles.
In particular, the influence of the gas flow incidence speed and the incidence angle on the slagging rate can be further considered in the embodiment of the invention. The influence of the incidence angle and the speed of the coal ash particles on slagging is determined by experimental research, namely, the functional relation curves of the influence of different incidence angles and speeds on slagging probability are obtained by experiments, and are respectively K1，K2Both values are 0 to 1, K1、K2Multiplying the probability of slag bonding by the probability of slag bonding to obtain the final probability. In the embodiment of the invention, the attachment probability of the current pulverized coal particles attaching to the heated surface of the boiler is the product of the coal ash attachment probability, the incidence angle influence coefficient and the incidence speed influence coefficient.
In an embodiment of the present invention, the factors determining the adhesion of the colliding particles include: particle and wall temperatures, incident velocity and angle, composition and viscosity, etc. Among them, the viscosity of the particles is the most important factor. At present, all studies have adopted critical viscosity (. mu.)ref) As a criterion for calculating the particle attachment probability. When the viscosity of the fly ash particles is lower than the critical viscosity, the probability that the fly ash particles can be adhered to the wall surface is considered to be 1; when the viscosity is higher than the critical viscosity, the sticking probability is considered as the ratio of the critical viscosity to the actual viscosity of the particles, and the model is specifically as follows:
Pi(TPs)＝1(μ＜μref)
in the above formula, piIs the probability that a particle group i having an average viscosity μ adheres to a wall surface, TpsIs the temperature of the particle group i.
In the embodiment of the invention, in order to make all coal powder coking model setting parameters have actual basis, the ash melting point test value of each coal powder is fully utilized to guide the parameter setting of the coking model, and a calculation model of the wall surface adhesion of the coal powder particles at the current temperature is constructed as follows, wherein the calculation mode of the probability Pi of the wall surface adhesion of the coal powder particles at the current temperature is as follows:
wherein Ti is the current temperature of the pulverized coal particles; ts is the softening temperature of the coal, and the value is equal to the softening temperature ST of the coal dust melting point test; ta is defined as the absolute adhesion temperature of the coal, and is equal to the coal dust melting point test flow temperature FT in numerical value; ps is defined as the probability of the coal dust particles adhering to the wall surface at the softening temperature Ts, and is calculated as follows, wherein DT is the deformation temperature of the coal dust ash in the melting point test:
based on the formula, the attachment probability of the coal dust particles adhering to the wall surface at present can be obtained, then a random value is generated for the current particles, when the random value is within the wall surface adhesion probability Pi at the current temperature, the coal dust is judged to be adhered to the wall surface, and the judgment mechanism is as follows:
the combustion model refers to a series of settings on combustion process parameters in CFD software, including but not limited to the input of coal dust physical properties; mixing mode of coal powder and air; physical parameters of the fuel and oxidant; combustion generation space, namely the shape, size, material and the like of a boiler hearth; and boundary conditions of combustion, such as the form and speed of an inlet and an outlet, the arrangement mode of coal powder at the inlet and the like. Furthermore, all parameters set in the CFD software with respect to the combustion process parameters belong to the category of the combustion model. Because the slagging process occurs in the combustion process, the slagging model can not exist independently from the combustion model. In the embodiment of the invention, therefore, the slagging model is added on the basis of the combustion model setting.
The rest of the content of this step is substantially the same as that of S102 in the above embodiment of the present invention, and the detailed content has been described in the above embodiment of the present invention, and is not described again here.
S203: and calculating the initial slagging condition based on the coupling model and the data in the boiler combustion numerical simulation database.
This step is substantially the same as S103 in the above embodiment of the present invention, and details have been described in the above embodiment of the present invention, and are not described herein again.
S204: and correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler based on the current slagging condition through a slagging growth model.
In the embodiment of the invention, the slagging growth model describes a dynamic process from the beginning to the stability of slagging, and mainly comprises the growth of the thickness of a slagging layer, the change of the slagging amount with time, the change of the physical property of the slag layer and the heat transfer through the slag layer.
The actual slagging process inevitably causes the change of the physical property of a slag layer, and many researches simulate the actual complex process by selecting a physical property parameter function which is as consistent as possible with the actual physical and chemical reaction. The physical parameters mainly comprise: the heat conductivity coefficient, porosity, absorptivity, emissivity, etc. of the slag layer. Among them, parameters affecting the formation of slag, the characteristics of slag formation and the significance of heat transfer must be considered, and the porosity and the thermal conductivity of the slag are the two most important parameters.
The porosity is solved by 3 methods: 1. the slag is divided into three layers artificially, the porosity value in each layer is different but keeps constant and does not change along with the generation of slag bonding; 2. the porosity is considered to be related to the solid phase volume fraction and the liquid phase volume fraction at which the slag layer reaches equilibrium; 3. porosity was calculated based on the sintering reaction that occurred between slag layers.
As the slagging grows continuously, the thermal resistance of the slag layer is increased gradually, the heat transfer is deteriorated, and the surface temperature of the slag layer is increased rapidly. Meanwhile, the viscosity of the particle size of the fly ash colliding with the wall surface that is already slagging is gradually reduced, and when the viscosity of the fly ash particles colliding with the wall surface is less than a certain value, the fly ash particles collide with the wall surface and are captured by the formed slag layer without slagging, which is mainly caused by the fact that the adhesion force of the slag layer is not enough to bear the gravity of the fly ash particles. At this time, the slagging process is stopped, and the fly ash particles collided with the wall surface flow in the gravity direction by their own weight.
The slagging growth model is based on the slagging model, and is used for calculating specific slagging conditions such as area, thickness and the like when the slagging model judges that slagging adhesion occurs at a certain position.
After the initial deposition layer is formed by primary judgment of the slagging model, along with thickening of the initial deposition layer, the smoke temperature is increased, the deposition rate is accelerated, the bonding strength between the deposit and between the deposit and the heating surface is increased, and the surface temperature of the deposition layer is increased until the fused or semi-fused particles deposited on the deposition layer are basically not solidified to form a viscous fluid layer, namely a capturing surface.
After the catching surface is formed, no matter what the viscosity, speed and collision angle of the soot, as long as the particles contacting the deposition layer are generally caught, the deposition layer is rapidly increased, the caught solid particles are dissolved on the deposition surface, the melting point or viscosity is increased, so that solidification occurs and a new catching surface is formed, and the temperature is reached when the temperature of the deposition surface reaches the limit viscosity value under the action of gravity, so that the formation of the deposition layer is not thickened and the soot on collision flows downwards along the surface of the pipe wall.
Parameters that affect the formation of slagging, the characteristics of slagging and the heat transfer must be considered, the porosity and the thermal conductivity of the ash being the two most important parameters. And calculating the porosity and the heat conductivity of the slag layer by using a required solution before simulation, and introducing the calculated solution into a slagging growth model.
In this step, the attachment probability of the current pulverized coal particles attaching to the heating surface of the boiler needs to be corrected based on the current slagging condition through the slagging growth model, so that the current slagging condition is calculated according to the currently corrected attachment probability in the next step, and the current attachment probability and the current slagging condition are always calculated in the following iterative process until the slagging of the heating surface of the boiler is stable.
Specifically, the step may specifically be: correcting the wall surface condition of the heating surface of the boiler and the temperature of coal ash according to the current slagging condition of the heating surface of the boiler; determining a corrected adhesion probability based on the corrected wall surface condition and the soot temperature. Specifically, in this step, the wall surface condition of the heated surface and the soot temperature may be corrected specifically after each determination as to whether or not soot particles are adhered.
The slagging growth model can be regarded as iteration of the slagging model, for example, 10 coal ash particles are adhered in the first combustion slagging simulation, then the heat exchange coefficient of the corresponding wall surface is changed due to the adhesion of the 10 particles in the second iteration, the change of the heat exchange condition causes the change of a temperature field at the wall surface, and the change of gas components generated by combustion is caused, wherein the change mainly influences the temperature of the coal ash due to the CO concentration, and the change of the property of the wall surface at the first adhesion part is ignored, namely the wall surface of the boiler is consistent with the slagging surface except the heat exchange coefficient; the second iteration assumes that 8 particles are adhered, and so on, until the next iteration is basically unchanged from the previous one, and the combustion slagging is stable. It is emphasized that in the present example, a correction to the wall conditions and to the soot temperature due to a change in the CO concentration resulting from a change in the wall heat transfer coefficient is required during each iteration.
S205: and calculating the current slagging condition according to the corrected attachment probability.
In the embodiment of the present invention, the step of correcting the attachment probability of the current pulverized coal particles to the heating surface of the boiler based on the current slagging condition through the slagging growth model needs to be executed circularly until the current slagging condition is calculated according to the corrected attachment probability, that is, the steps of S204 and S205 are executed circularly until the slagging of the heating surface of the boiler is stable. For the specific content of calculating the current slag bonding condition, reference may be made to the specific content of calculating the initial slag bonding condition in the slag bonding model, which is not described herein again.
S206: and when the slagging growth condition shows that the slagging of the heating surface of the boiler is stable, calculating relevant parameters of the heating surface of the boiler by taking the condition of the heating surface of the boiler with stable slagging as a combustion simulation boundary condition.
This step is substantially the same as S105 in the above embodiment of the present invention, and for details, reference is made to the above embodiment of the present invention, which is not repeated herein.
According to the boiler slagging prediction method based on numerical simulation provided by the embodiment of the invention, after the initial slagging condition is obtained through the slagging model based on the limiting condition of the combustion model, the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler is corrected and iterated based on the slagging model, namely the slagging growth model, so that the simulated slagging growth condition is more in line with the actual condition, and the finally calculated related parameters are more accurate and more in line with the actual condition.
The boiler slagging prediction device based on numerical simulation provided by the embodiment of the invention is introduced below, and the boiler slagging prediction device based on numerical simulation described below and the boiler slagging prediction method based on numerical simulation described above can be referred to correspondingly.
Referring to fig. 3, fig. 3 is a block diagram illustrating a boiler slag formation prediction apparatus based on numerical simulation according to an embodiment of the present invention.
Referring to fig. 3, in an embodiment of the present invention, a boiler slagging prediction apparatus based on numerical simulation may include:
the calling module 100: the method is used for calling a boiler combustion numerical simulation database.
The coupling module 200: and the boiler combustion numerical simulation database is used for mutually coupling a preset slagging model and a combustion model corresponding to the boiler combustion numerical simulation database to obtain a coupling model.
The initial slagging module 300: for calculating an initial slagging condition based on the coupling model and data in the boiler combustion numerical simulation database.
Slagging and growing module 400: the system is used for calculating the slagging condition based on the initial slagging condition and a preset slagging growth model; the slagging growth model is an iterative model of the slagging model, and is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler.
The stabilization module 500: and when the slagging growth condition shows that the slagging of the heating surface of the boiler is stable, the method is used for calculating relevant parameters of the heating surface of the boiler by taking the condition of the heating surface of the boiler with stable slagging as a combustion simulation boundary condition.
Preferably, in the embodiment of the present invention, the slagging model is used to calculate an attachment probability of the current pulverized coal particles attaching to the heated surface of the boiler;
the slagging growth module 400 may include:
a correction unit: the device is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler based on the current slagging condition through the slagging growth model;
an iteration unit: and the method is used for calculating the current slagging condition according to the corrected adhesion probability, and circularly executing the step of correcting the adhesion probability of the current pulverized coal particles adhering to the heating surface of the boiler based on the current slagging condition through the slagging growth model until the current slagging condition is calculated according to the corrected adhesion probability until the slagging of the heating surface of the boiler is stable.
Preferably, in the embodiment of the present invention, the attachment probability of the current pulverized coal particles to the heated surface of the boiler is the product of the attachment probability of the coal ash, the incidence angle influence coefficient and the incidence speed influence coefficient.
Preferably, in an embodiment of the present invention, the correction unit includes:
a correction subunit: the method is used for correcting the wall surface condition of the heating surface of the boiler and the temperature of the coal ash according to the current slagging condition of the heating surface of the boiler.
A calculation subunit: and determining a corrected adhesion probability based on the corrected wall surface condition and the soot temperature.
Preferably, in the embodiment of the present invention, the related parameters of the heated surface of the boiler include any one or any combination of the following:
the heat exchange condition of the heating surface of the boiler, the velocity field in the boiler, the temperature field in the boiler, the particle concentration distribution field in the boiler and the gas substance concentration distribution field in the boiler.
Preferably, in the embodiment of the present invention, the boiler combustion numerical simulation database is a CFD simulation database.
The boiler slagging prediction apparatus based on the numerical simulation of this embodiment is used to implement the boiler slagging prediction method based on the numerical simulation, and thus specific embodiments of the boiler slagging prediction apparatus based on the numerical simulation can be seen in the foregoing example portions of the boiler slagging prediction method based on the numerical simulation, for example, the calling module 100, the coupling module 200, the initial slagging module 300, the slagging growth module 400, and the stabilizing module 500 are respectively used to implement the steps S101 to S105 of the boiler slagging prediction method based on the numerical simulation, so specific embodiments thereof may refer to descriptions of corresponding respective partial examples, and are not described herein again.
The following introduces a boiler slagging prediction device based on numerical simulation according to an embodiment of the present invention, and the boiler slagging prediction device based on numerical simulation described below, the boiler slagging prediction method based on numerical simulation described above, and the boiler slagging prediction apparatus based on numerical simulation may be referred to in correspondence with each other.
Referring to fig. 4, fig. 4 is a block diagram illustrating a boiler slagging prediction apparatus based on numerical simulation according to an embodiment of the present invention.
Referring to fig. 4, the boiler slagging prediction apparatus based on numerical simulation may include a processor 11 and a memory 12.
The memory 12 is used for storing a computer program; the processor 11 is configured to implement the boiler slagging prediction method based on numerical simulation described in the above embodiment of the invention when executing the computer program.
The processor 11 of the boiler slagging prediction device based on numerical simulation of this embodiment is used to install the boiler slagging prediction device based on numerical simulation described in the above embodiment of the invention, and the processor 11 and the memory 12 are combined to implement the boiler slagging prediction method based on numerical simulation described in any embodiment of the invention. Therefore, the specific implementation manner of the boiler slagging prediction device based on the numerical simulation can be seen in the foregoing example section of the boiler slagging prediction method based on the numerical simulation, and the specific implementation manner thereof may refer to the description of the corresponding examples of each section, and is not described herein again.
The invention also provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement a boiler slagging prediction method based on numerical simulation introduced in any one of the above embodiments of the invention. The rest can be referred to the prior art and will not be described in an expanded manner.
The embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same or similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.
The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in Random Access Memory (RAM), memory, Read Only Memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.
Finally, it should also be noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The boiler slagging prediction method based on numerical simulation, the boiler slagging prediction device based on numerical simulation, the boiler slagging prediction equipment based on numerical simulation and the computer readable storage medium provided by the invention are described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.
Claims (10)
1. A boiler slagging prediction method based on numerical simulation is characterized by comprising the following steps:
calling a boiler combustion numerical simulation database;
coupling a preset slagging model with a combustion model corresponding to the boiler combustion numerical simulation database to obtain a coupling model;
calculating an initial slagging condition based on the coupling model and data in the boiler combustion numerical simulation database;
calculating the slagging growth condition based on the initial slagging condition and a preset slagging growth model; the slagging growth model is an iterative model of the slagging model, and is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler;
and when the slagging growth condition shows that the slagging of the heating surface of the boiler is stable, calculating relevant parameters of the heating surface of the boiler by taking the condition of the heating surface of the boiler with stable slagging as a combustion simulation boundary condition.
2. The method according to claim 1, wherein the slagging model is used for calculating the attachment probability of the current pulverized coal particles to the heating surface of the boiler;
the calculating of the slagging growth condition based on the initial slagging condition and a preset slagging growth model comprises:
correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler based on the current slagging condition through a slagging growth model;
and calculating the current slagging condition according to the corrected adhesion probability, and circularly executing the step of correcting the adhesion probability of the current pulverized coal particles adhering to the heating surface of the boiler based on the current slagging condition through the slagging growth model until the current slagging condition is calculated according to the corrected adhesion probability until the slagging of the heating surface of the boiler is stable.
3. The method according to claim 2, wherein the attachment probability of the current pulverized coal particles to the heated surface of the boiler is the product of the attachment probability of the coal ash, an incidence angle influence coefficient and an incidence speed influence coefficient.
4. The method of claim 3, wherein the correcting, by the slagging growth model, the attachment probability of the current pulverized coal particles to the boiler heating surface based on the current slagging condition comprises:
correcting the wall surface condition of the heating surface of the boiler and the temperature of coal ash according to the current slagging condition of the heating surface of the boiler;
determining a corrected adhesion probability based on the corrected wall surface condition and the soot temperature.
5. The method of claim 1, wherein the relevant parameters of the boiler heating surface include any one or any combination of the following:
the heat exchange condition of the heating surface of the boiler, the velocity field in the boiler, the temperature field in the boiler, the particle concentration distribution field in the boiler and the gas substance concentration distribution field in the boiler.
6. The method of claim 1, wherein the boiler combustion numerical simulation database is a CFD simulation database.
7. A boiler slagging prediction apparatus based on numerical simulation, comprising:
a calling module: the simulation database is used for calling a boiler combustion numerical value;
a coupling module: the boiler combustion numerical simulation system is used for coupling a preset slagging model with a combustion model corresponding to the boiler combustion numerical simulation database to obtain a coupling model;
an initial slagging module: for calculating an initial slagging condition based on the coupling model and data in the boiler combustion numerical simulation database;
a slagging and growing module: the system is used for calculating the slagging condition based on the initial slagging condition and a preset slagging growth model; the slagging growth model is an iterative model of the slagging model, and is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler;
a stabilization module: and when the slagging growth condition shows that the slagging of the heating surface of the boiler is stable, the method is used for calculating relevant parameters of the heating surface of the boiler by taking the condition of the heating surface of the boiler with stable slagging as a combustion simulation boundary condition.
8. The device according to claim 7, wherein the slagging model is used for calculating the attachment probability of the current pulverized coal particles to the heating surface of the boiler;
the slagging growth module comprises:
a correction unit: the device is used for correcting the attachment probability of the current pulverized coal particles attached to the heating surface of the boiler based on the current slagging condition through the slagging growth model;
an iteration unit: and the method is used for calculating the current slagging condition according to the corrected adhesion probability, and circularly executing the step of correcting the adhesion probability of the current pulverized coal particles adhering to the heating surface of the boiler based on the current slagging condition through the slagging growth model until the current slagging condition is calculated according to the corrected adhesion probability until the slagging of the heating surface of the boiler is stable.
9. A boiler slagging prediction apparatus based on numerical simulation, the apparatus comprising:
a memory: for storing a computer program;
a processor: the steps for implementing a boiler slagging prediction method based on numerical simulation according to any of claims 1 to 6 when executing said computer program.
10. A computer-readable storage medium, having stored thereon a computer program which, when being executed by a processor, carries out the steps of the numerical simulation based boiler slagging prediction method according to any one of claims 1 to 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110012774.6A CN112784405B (en) | 2021-01-06 | 2021-01-06 | Boiler slagging prediction method and related device based on numerical simulation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110012774.6A CN112784405B (en) | 2021-01-06 | 2021-01-06 | Boiler slagging prediction method and related device based on numerical simulation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112784405A true CN112784405A (en) | 2021-05-11 |
| CN112784405B CN112784405B (en) | 2024-06-11 |
Family
ID=75755694
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110012774.6A Active CN112784405B (en) | 2021-01-06 | 2021-01-06 | Boiler slagging prediction method and related device based on numerical simulation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112784405B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113344909A (en) * | 2021-07-01 | 2021-09-03 | 中国石油大学(北京) | Method and device for identifying and displaying coking of flame-permeable high-temperature filter of thermal power boiler |
| CN113485499A (en) * | 2021-08-26 | 2021-10-08 | 润电能源科学技术有限公司 | Coal feeding regulation and control method for coal quality working condition change |
| CN114019133A (en) * | 2021-11-09 | 2022-02-08 | 华电新疆哈密煤电开发有限公司 | Coal quality slagging characteristic comprehensive judgment method based on judgment index |
| CN116720446A (en) * | 2023-07-16 | 2023-09-08 | 天津大学 | Method for monitoring thickness of slag layer of water-cooled wall of boiler in real time |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101996260A (en) * | 2009-08-14 | 2011-03-30 | 华东电力试验研究院有限公司 | Method for predicting furnace slagging property by numerical simulation |
| US20170177758A1 (en) * | 2015-12-22 | 2017-06-22 | Doosan Heavy Industries & Construction Co., Ltd. | Method for predicting slagging production position and slagging production possibility in furnace |
| CN109829189A (en) * | 2018-12-20 | 2019-05-31 | 上海理工大学 | A kind of Boiler Furnace slagging thickness judgment method based on numerical simulation |
| CN111242279A (en) * | 2020-01-03 | 2020-06-05 | 浙江浙能技术研究院有限公司 | System and method for predicting slagging of hearth of ultra-supercritical pulverized coal boiler |
| CN111550763A (en) * | 2020-01-20 | 2020-08-18 | 张铭源 | Method for monitoring ash pollution on heating surface of boiler |
-
2021
- 2021-01-06 CN CN202110012774.6A patent/CN112784405B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101996260A (en) * | 2009-08-14 | 2011-03-30 | 华东电力试验研究院有限公司 | Method for predicting furnace slagging property by numerical simulation |
| US20170177758A1 (en) * | 2015-12-22 | 2017-06-22 | Doosan Heavy Industries & Construction Co., Ltd. | Method for predicting slagging production position and slagging production possibility in furnace |
| CN109829189A (en) * | 2018-12-20 | 2019-05-31 | 上海理工大学 | A kind of Boiler Furnace slagging thickness judgment method based on numerical simulation |
| CN111242279A (en) * | 2020-01-03 | 2020-06-05 | 浙江浙能技术研究院有限公司 | System and method for predicting slagging of hearth of ultra-supercritical pulverized coal boiler |
| CN111550763A (en) * | 2020-01-20 | 2020-08-18 | 张铭源 | Method for monitoring ash pollution on heating surface of boiler |
Non-Patent Citations (1)
| Title |
|---|
| 方庆艳等: "W 火焰锅炉结渣特性数值模拟", 中国电机工程学报, vol. 28, no. 23, pages 1 - 7 * |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113344909A (en) * | 2021-07-01 | 2021-09-03 | 中国石油大学(北京) | Method and device for identifying and displaying coking of flame-permeable high-temperature filter of thermal power boiler |
| CN113344909B (en) * | 2021-07-01 | 2023-12-08 | 中国石油大学(北京) | Method and device for identifying and displaying flame penetration height Wen Lvjing coking of thermal power boiler |
| CN113485499A (en) * | 2021-08-26 | 2021-10-08 | 润电能源科学技术有限公司 | Coal feeding regulation and control method for coal quality working condition change |
| CN113485499B (en) * | 2021-08-26 | 2022-11-01 | 润电能源科学技术有限公司 | Coal feeding regulation and control method for coal quality working condition change |
| CN114019133A (en) * | 2021-11-09 | 2022-02-08 | 华电新疆哈密煤电开发有限公司 | Coal quality slagging characteristic comprehensive judgment method based on judgment index |
| CN116720446A (en) * | 2023-07-16 | 2023-09-08 | 天津大学 | Method for monitoring thickness of slag layer of water-cooled wall of boiler in real time |
| CN116720446B (en) * | 2023-07-16 | 2023-11-21 | 天津大学 | Method for monitoring thickness of slag layer of water-cooled wall of boiler in real time |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112784405B (en) | 2024-06-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112784405A (en) | Boiler slagging prediction method based on numerical simulation and related device | |
| Wang et al. | Understanding ash deposition for Zhundong coal combustion in 330 MW utility boiler: Focusing on surface temperature effects | |
| Wu et al. | Ash deposition and slagging behavior of Chinese Xinjiang high-alkali coal in 3 MWth pilot-scale combustion test | |
| Degereji et al. | Prediction of ash slagging propensity in a pulverized coal combustion furnace | |
| Walsh et al. | Deposition of bituminous coal ash on an isolated heat exchanger tube: effects of coal properties on deposit growth | |
| Zheng et al. | Simulating growth of ash deposit in boiler heat exchanger tube based on CFD dynamic mesh technique | |
| Erickson et al. | Modelling of fouling and slagging in coal-fired utility boilers | |
| Shimogori et al. | Effects of fine ash particles and alkali metals on ash deposition characteristics at the initial stage of ash deposition determined in 1.5 MWth pilot plant tests | |
| Zhou et al. | Large-eddy simulation of ash deposition in a large-scale laboratory furnace | |
| Mu et al. | Unsteady CFD simulation on ash particle deposition and removal characteristics in tube banks: Focusing on particle diameter, flow velocity, and temperature | |
| Bhuiyan et al. | Modeling of slagging in industrial furnace: a comprehensive review | |
| Arvelakis et al. | Rheology of fly ashes from coal and biomass co-combustion | |
| Laxminarayan et al. | Tensile adhesion strength of biomass ash deposits: effect of the temperature gradient and ash chemistry | |
| Hu et al. | Research on element migration and ash deposition characteristics of high-alkali coal in horizontal liquid slagging cyclone furnace | |
| Zhou et al. | Numerical simulation of ash deposition behavior with a novel erosion model using dynamic mesh | |
| CN103539347A (en) | Inorganic fiber with solid waste as raw material and production method thereof | |
| CN101996260A (en) | Method for predicting furnace slagging property by numerical simulation | |
| Miao et al. | Numerical prediction on deposition growth and heat transfer characteristics burning high–sodium pulverized coal | |
| Kleinhans et al. | Large Eddy Simulation of a particle-laden flow around a cylinder: Importance of thermal boundary layer effects for slagging and fouling | |
| Aoki et al. | Shear strength testing of synthetic ash: the role of surface vs interparticle adhesions | |
| Hsieh | Viscous deformation as a measure of heat work during coal ash fusibility testing | |
| Stam et al. | Review of models and tools for slagging and fouling prediction for biomass co-combustion | |
| Forstner et al. | CFD simulation of ash deposit formation in fixed bed biomass furnaces and boilers | |
| CN107884430A (en) | A kind of method of the carbonaceous material ash melting temperature such as forecasting coal | |
| Balan et al. | Experimental study of high-temperature chlorine-induced corrosion in dependence of gas velocity |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |