CN-122006898-A - Thermal power generating unit electrostatic dust collection efficiency optimization method and system based on multivariate prediction

CN122006898ACN 122006898 ACN122006898 ACN 122006898ACN-122006898-A

Abstract

The invention relates to the technical field of thermal power generating unit dust removal, and discloses a thermal power generating unit electrostatic dust removal efficiency optimization method and system based on multivariate prediction, comprising the steps of constructing a three-dimensional model of a flue from an outlet section of a boiler air preheater to an inlet section of an electrostatic precipitator; the method comprises the steps of carrying out fluid dynamics simulation on a flue gas flow field through a three-dimensional flue model, evaluating the uniformity of the flue gas flow field of an inlet flue of the electrostatic precipitator according to a fluid dynamics simulation result, analyzing the current flow distribution deviation cause based on the uniformity of the flue gas flow field of the inlet flue of the electrostatic precipitator, and constructing flue gas flow field optimization measures by combining the deviation cause. The invention combines the structured grid discrete, iterative collision transfer, macroscopic field reconstruction and other fine simulation flows of the lattice Boltzmann technology, can output reliable multi-load working condition flue gas flow field simulation data, and performs flow field topological characteristic and uniformity index analysis based on the flue gas flow field simulation data, thereby supporting the accurate formulation of electrostatic dust removal efficiency optimization measures.

Inventors

MA QINLIANG
LI SHIZHUANG
ZHANG YUEMING

Assignees

华电国际电力股份有限公司邹县发电厂

Dates

Publication Date: 20260512
Application Date: 20251225

Claims (10)

1. The thermal power generating unit electrostatic dust collection efficiency optimization method based on multivariable prediction is characterized by comprising the following steps of: s1, constructing a three-dimensional model of a flue from an outlet section of a boiler air preheater to an inlet section of an electrostatic precipitator based on pre-acquired structural data of the outlet flue of the boiler air preheater and the inlet flue of the electrostatic precipitator; S2, collecting flue gas parameters of an inlet flue of the electrostatic precipitator, taking the flue gas parameters as boundary conditions of a three-dimensional flue model, carrying out fluid dynamics simulation on a flue gas flow field through the three-dimensional flue model, and evaluating the uniformity of the flue gas flow field of the inlet flue of the electrostatic precipitator according to a fluid dynamics simulation result; s3, analyzing the current flow distribution deviation factor based on the uniformity of the flue gas flow field of the inlet flue of the electrostatic precipitator, and constructing flue gas flow field optimization measures by combining the deviation factor so as to realize flow field optimization from the outlet flue of the air preheater of the boiler to the inlet flue of the electrostatic precipitator.
2. The method for optimizing electrostatic dust collection efficiency of a thermal power generating unit based on multivariate prediction according to claim 1, wherein the constructing a three-dimensional model of a flue from an outlet section of a boiler air preheater to an inlet section of an electrostatic precipitator based on the pre-acquired structural data of the outlet flue of the boiler air preheater and the inlet flue of the electrostatic precipitator comprises: collecting structural data of an outlet flue of the boiler air preheater and an inlet flue of the electrostatic precipitator, carrying out standardized treatment, and extracting geometric characteristics of the boiler air preheater outlet flue and the inlet flue of the electrostatic precipitator in the standardized structural data; constructing an initial flue three-dimensional grid model by utilizing a structured grid division technology and combining the geometric characteristics of the flue; And (3) acquiring the fluid medium attribute and the fluid medium constraint of the outlet flue of the boiler air preheater and the inlet flue of the electrostatic precipitator, and coupling boundary conditions and physical parameters of the initial flue three-dimensional grid model to obtain a flue three-dimensional model from the outlet section of the boiler air preheater to the inlet section of the electrostatic precipitator.
3. The thermal power generating unit electrostatic dust collection efficiency optimization method based on multivariate prediction according to claim 2 is characterized in that the fluid medium properties of the boiler air preheater outlet flue and the electrostatic precipitator inlet flue comprise fluid type, density, viscosity, specific heat capacity, heat conductivity coefficient, smoke component concentration and smoke dust particle characteristics, and the fluid medium constraints comprise boundary constraint, physical constraint, flow state constraint and operation condition constraint.
4. The thermal power generating unit electrostatic dust collection efficiency optimization method based on multivariate prediction according to claim 1, wherein the collecting the flue gas parameters of the inlet flue of the electrostatic precipitator and taking the flue gas parameters as boundary conditions of a three-dimensional model of the flue, performing hydrodynamic simulation on the flue gas flow field through the three-dimensional model of the flue, and evaluating the uniformity of the flue gas flow field of the inlet flue of the electrostatic precipitator according to the hydrodynamic simulation result comprises: Collecting multi-dimensional smoke parameters of an inlet section of the electrostatic precipitator under different load operation conditions of the boiler, and taking the multi-dimensional smoke parameters as input boundary conditions of a three-dimensional model of a flue; The method comprises the steps of constructing a flue gas flow field simulation scene of an inlet flue of an electrostatic precipitator by taking a three-dimensional flue model as a carrier, executing fluid dynamics simulation on the flue gas flow field in the simulation scene by combining with a lattice Boltzmann technology, and outputting flue gas flow field simulation data under different load operation conditions of a boiler; and analyzing the topological characteristics and topological uniformity indexes of the flue gas flow field based on the flue gas flow field simulation data of the boiler under different load operation conditions, and evaluating the uniformity of the flue gas flow field of the inlet flue of the electrostatic precipitator by combining the topological characteristics and the topological uniformity indexes of the flow field.
5. The method for optimizing the electrostatic dust collection efficiency of the thermal power generating unit based on the multivariate prediction according to claim 4, wherein the multidimensional flue gas parameters of the inlet section of the electrostatic precipitator under different load operation conditions of the boiler comprise flue gas flow rates, temperatures and pressures of different flues of the electrostatic dust collection inlet and different sections of the same flue under different load operation conditions of the boiler.
6. The method for optimizing electrostatic dust collection efficiency of a thermal power generating unit based on multivariate prediction according to claim 5, wherein the steps of constructing a flue gas flow field simulation scene of an inlet flue of an electrostatic precipitator by taking a three-dimensional flue model as a carrier, and executing fluid dynamics simulation on the flue gas flow field in the simulation scene by combining a lattice boltzmann technique, and outputting flue gas flow field simulation data of a boiler under different load operation conditions comprise: Discretizing the three-dimensional model of the flue into a structured grid required by the lattice Boltzmann technique, and marking a boundary area in the structured grid; constructing flue gas flow field simulation scenes under different load operation conditions of the boiler, converting multi-dimensional flue gas parameters into a distribution function form in each flue gas flow field simulation scene, assigning values to corresponding boundary area grids, and outputting a plurality of initial fluid grids; Performing local collision calculation and adjacent grid flow transfer on all initial fluid grids in an iterative manner, reconstructing a macroscopic field in real time after each iteration until the flow field of each boiler load operation condition meets a convergence state, and outputting the flue gas full flow field data of each boiler load operation condition; And (3) interpolating and mapping the flue gas full flow field data to a target section, calculating the speed vector, the pressure, the turbulence intensity and the fly ash concentration of each position on the target section, generating a target section data set under each boiler load operation condition, and taking the target section data set as flue gas flow field simulation data.
7. The method for optimizing electrostatic precipitation efficiency of a thermal power generating unit based on multivariate prediction according to claim 6, wherein the iterative execution of local collision calculation and adjacent grid flow transfer on all initial fluid grids, the reconstruction of macroscopic fields in real time after each iteration until each boiler load operation condition flow field meets a convergence state, and the output of flue gas full flow field data of each boiler load operation condition comprises: Simulating a collision process of the distribution function on each initial fluid lattice node based on the preset relaxation time, so that the collision process relaxes to a local equilibrium state, and a distribution function after collision is obtained; transmitting the collided distribution function to adjacent fluid lattice nodes according to the target discrete speed direction, and applying corresponding distribution function boundary conditions at boundary fluid lattice nodes to obtain an updated distribution function; Performing iterative local collision calculation and adjacent lattice flow transfer processes, and summing distribution functions of all directions on fluid lattice sub-nodes after each iteration to reconstruct a macroscopic field in real time; stopping the iterative process when the flow field monitoring index of each boiler load operation condition reaches a steady state, and outputting the flue gas full flow field data in a convergence state under each boiler load operation condition.
8. The method for optimizing electrostatic dust collection efficiency of a thermal power generating unit based on multivariate prediction according to claim 4, wherein the analyzing the topological feature and topological uniformity index of the flue gas flow field based on the flue gas flow field simulation data under different load operation conditions of the boiler, and evaluating the flue gas flow field uniformity of the inlet flue of the electrostatic precipitator by combining the topological feature and the topological uniformity index of the flue gas flow field comprises: carrying out flow field topological feature analysis on the flue gas flow field simulation data by utilizing a streamline tracking algorithm, identifying flue gas flow field topological features under different load operation conditions of the boiler, and converting the flue gas flow field topological features into flue gas flow field feature vectors; And comparing the characteristic vector of the flue gas flow field with a preset topological uniformity index, and evaluating the uniformity of the flue gas flow field of the inlet flue of the electrostatic precipitator based on a comparison result.
9. The thermal power generating unit electrostatic precipitation efficiency optimization method based on multivariate prediction according to claim 8, wherein comparing the flue gas flow field feature vector with a preset topological uniformity index and evaluating the flue gas flow field uniformity of the inlet flue of the electrostatic precipitator based on the comparison result comprises: if the feature vector of the flue gas flow field is larger than or equal to the topological uniformity index, the flue gas flow field of the inlet flue of the electrostatic precipitator is in a uniform state; If the feature vector of the flue gas flow field is smaller than the topological uniformity index, the flue gas flow field of the inlet flue of the electrostatic precipitator is in an uneven state, and the step S3 is executed.
10. A thermal power generating unit electrostatic precipitation efficiency optimization system based on multivariate prediction, for implementing the thermal power generating unit electrostatic precipitation efficiency optimization method based on multivariate prediction as claimed in any one of claims 1-9, characterized in that the system comprises: The flue three-dimensional model construction module is used for constructing a flue three-dimensional model from the outlet section of the boiler air preheater to the inlet section of the electrostatic precipitator based on the pre-acquired structural data of the outlet flue of the boiler air preheater and the inlet flue of the electrostatic precipitator; The flue gas flow field simulation module is used for collecting flue gas parameters of the inlet flue of the electrostatic precipitator and taking the flue gas parameters as boundary conditions of the three-dimensional flue model, carrying out fluid dynamics simulation on the flue gas flow field through the three-dimensional flue model, and evaluating the uniformity of the flue gas flow field of the inlet flue of the electrostatic precipitator according to the fluid dynamics simulation result; The flow field optimization module is used for analyzing the current flow distribution deviation factor based on the uniformity of the flue gas flow field of the inlet flue of the electrostatic precipitator, and combining the deviation factor to construct a flue gas flow field optimization measure so as to realize flow field optimization from the outlet flue of the air preheater of the boiler to the inlet flue of the electrostatic precipitator.

Description

Thermal power generating unit electrostatic dust collection efficiency optimization method and system based on multivariate prediction Technical Field The invention relates to the technical field of thermal power generating unit dust removal, in particular to a thermal power generating unit electrostatic dust removal efficiency optimization method and system based on multivariate prediction. Background The thermal power generating unit is an electric power device for generating electricity by burning fossil fuel such as coal and utilizing steam to drive a generator. The thermal power generating unit mainly comprises a boiler, a steam turbine, a generator, a cooling system and the like, and a large amount of flue gas generated in the combustion process needs to be purified through a flue gas treatment device so as to reduce the emission of harmful substances. The electrostatic dust collector is a key device for removing solid particles in flue gas in a thermal power generating unit, and the high-voltage electric field is utilized to charge the particles and collect the particles through electric field force, so that the purpose of purifying the flue gas is achieved. The electrostatic dust collection efficiency of the thermal power generating unit is optimized because the efficiency of the electrostatic dust collector directly influences the concentration of the discharged matters and the environmental pollution control. Therefore, the electrostatic dust collection efficiency is optimized, the dust collection effect can be improved, the harmful emission is reduced, the overall environmental protection performance of the thermal power generating unit can be improved, and increasingly strict environmental protection regulations are met. If the uniformity of the flue gas flow field of the inlet flue of the electrostatic precipitator is not considered in the effect optimization, the flue gas flow is possibly uneven, and the air flow speed of a partial area is too high or too low, so that the dust removal efficiency is unbalanced. Specifically, the uneven air flow can cause that the fly ash in partial flue gas areas can not be effectively captured, so that the overall dust removal efficiency is reduced, and even the electrostatic precipitator can not reach the expected dust removal effect in certain areas, thereby affecting the achievement of emission standards, reducing the energy utilization efficiency of the system and increasing the operation cost. For the problems in the related art, no effective solution has been proposed at present. Disclosure of Invention Aiming at the problems in the related art, the invention provides a thermal power generating unit electrostatic dust collection efficiency optimization method and system based on multivariate prediction, so as to overcome the technical problems existing in the related art. For this purpose, the invention adopts the following specific technical scheme: According to a first aspect of the invention, there is provided a thermal power generating unit electrostatic precipitation efficiency optimization method based on multivariate prediction, the method comprising: s1, constructing a three-dimensional model of a flue from an outlet section of a boiler air preheater to an inlet section of an electrostatic precipitator based on pre-acquired structural data of the outlet flue of the boiler air preheater and the inlet flue of the electrostatic precipitator; S2, collecting flue gas parameters of an inlet flue of the electrostatic precipitator, taking the flue gas parameters as boundary conditions of a three-dimensional flue model, carrying out fluid dynamics simulation on a flue gas flow field through the three-dimensional flue model, and evaluating the uniformity of the flue gas flow field of the inlet flue of the electrostatic precipitator according to a fluid dynamics simulation result; s3, analyzing the current flow distribution deviation factor based on the uniformity of the flue gas flow field of the inlet flue of the electrostatic precipitator, and constructing flue gas flow field optimization measures by combining the deviation factor so as to realize flow field optimization from the outlet flue of the air preheater of the boiler to the inlet flue of the electrostatic precipitator. Further, based on the pre-acquired structural data of the outlet flue of the boiler air preheater and the inlet flue of the electrostatic precipitator, constructing a three-dimensional model of the flue from the outlet section of the boiler air preheater to the inlet section of the electrostatic precipitator comprises: collecting structural data of an outlet flue of the boiler air preheater and an inlet flue of the electrostatic precipitator, carrying out standardized treatment, and extracting geometric characteristics of the boiler air preheater outlet flue and the inlet flue of the electrostatic precipitator in the standardized structural data; constructing an initial flue three