CN-121787869-B - Method and system for matching raw material characteristics with biomass gasification coupling coal-fired power generation ratio

CN121787869BCN 121787869 BCN121787869 BCN 121787869BCN-121787869-B

Abstract

The invention relates to the technical field of coal-fired power generation and discloses a method and a system for matching raw material characteristics with biomass gasification coupling coal-fired power generation, wherein the method collects on-line and laboratory analysis data of biomass and coal-fired raw materials, a characteristic coordinate system is mapped and discretized to construct a raw material characteristic phase space grid, a working condition response Markov chain is built by fusing gasification and combustion process monitoring data, a matching feedforward control function set is generated through multi-step forward simulation and multi-objective optimization, and an automatic control system is embedded to realize dynamic adjustment of fuel matching and combustion working conditions.

Inventors

LI CUNLEI
FAN QINSHAN
FU YIWEI
Cheng Manqiu
ZHENG SHIJIN
DING HONG
ZHOU FEI
ZHANG PENG
Ye Xingpei
LIU MINGRUI
LIU ZHOU
Jie Xiaochen

Assignees

江苏省国信研究院有限公司

Dates

Publication Date: 20260512
Application Date: 20260305

Claims (8)

1. The method for matching the characteristics of raw materials with the gasification coupling coal-fired power generation ratio of the biomass is characterized by comprising the following steps of: S1, collecting online and laboratory analysis data of biomass and coal raw materials, constructing a unified characteristic coordinate system, discretizing, and generating a raw material characteristic phase space grid for representing batch and time variation; s2, fusing gasification products with on-line monitoring data of boiler combustion, and constructing a working condition response Markov chain along a time evolution path of a raw material characteristic phase space grid; S3, based on a working condition response Markov chain, carrying out forward simulation on state transition under different blending assumptions, and generating a proportion feedforward control function set for giving fuel proportion and auxiliary control quantity for each state; S4, embedding a proportioning feedforward control function set into the automatic control system of the fuel feeding and the boiler, calling a corresponding function according to the state recognized in real time, and executing dynamic adjustment of the proportioning of biomass and fire coal and the combustion working condition, wherein the step of constructing the working condition response Markov chain comprises the following steps: The method comprises the steps of synchronously collecting gasification and combustion process data at the key positions of a gasification furnace outlet and a hearth, aligning the data with a raw material collecting timestamp to form a process monitoring data stream, counting gasification and combustion response at each moment into corresponding units according to raw material characteristic phase space grid units corresponding to raw materials at each moment to enable the raw material characteristic phase space grid to be updated into a raw material-response combined distribution supporting body, tracking a moving track of raw material characteristics on the raw material characteristic phase space grid according to time sequence, regarding each accessed raw material characteristic phase space grid unit as a state, recording jumps among the raw material characteristic phase space grid units falling at adjacent moment as state transitions, counting to obtain transition frequency and condition response change among state pairs, and constructing a working condition response Markov chain, wherein the step of executing dynamic adjustment of biomass and coal proportioning and combustion working conditions comprises the following steps: Continuously collecting online characteristic data of biomass and fire coal in real time in an operation stage, positioning the current raw material characteristic, and identifying a corresponding state number of the current working condition in a working condition response Markov chain; the control system selects a matched function from the proportioning feedforward control function set through the current state number, and calculates the biomass blending proportion, the feeding quantity set value and the air distribution proportion which are needed to be adopted at the current moment; The control quantity is input into a boiler combustion control loop as feedforward setting, and is matched with a hearth temperature and oxygen quantity feedback signal to realize the cooperative regulation of feedforward and feedback, and the proportioning strategy is synchronously switched during state switching.
2. The method for matching raw material characteristics to biomass gasification coupled coal-fired power generation proportioning of claim 1, wherein the step of generating a raw material characteristic phase space grid comprises: Arranging on-line detection devices at measuring points of a conveying belt, a feeding hopper and a pulverizing system, acquiring industrial analysis indexes of biomass and coal, and recording corresponding time stamps and position information of feeding points; Mapping industrial analysis indexes in a raw material characteristic data source to a multi-dimensional characteristic coordinate system, wherein each dimension corresponds to key raw material characteristics respectively, dividing intervals on each dimension according to standard or statistical distribution based on historical data, and forming a raw material characteristic phase space grid on the multi-dimensional characteristic coordinate system; statistical information for each feedstock property phase space grid cell is maintained in the feedstock property phase space grid.
3. The method for matching raw material characteristics to biomass gasification coupled coal-fired power generation ratio according to claim 2, wherein the step of obtaining industrial analysis indexes of biomass and coal comprises the steps of: An online moisture meter and a near infrared spectrometer are arranged at a measuring point of a conveying belt, a weighing belt and an ash content rapid analyzer are arranged at a measuring point of a feeding hopper, and a granularity analyzer and an industrial camera are arranged at a measuring point of a powder making system; Collecting industrial analysis index data of the raw materials in real time through each online detection device; Binding output data of all online detection devices with a timestamp generated by a unified clock source, marking a charging point position number to form a raw material online detection data packet, simultaneously carrying out standard industrial analysis on biomass and coal raw materials before mixing in a laboratory with each day or each batch as a period to form a laboratory verification data packet, and forming the raw material characteristic data source by the raw material online detection data packet and the laboratory verification data packet.
4. The method for matching raw material characteristics to biomass gasification coupled coal-fired power generation proportioning according to claim 1, wherein the specific steps of constructing a working condition response markov chain include: Traversing all units in the raw material characteristic phase space grid, screening out units with a sample counter larger than 0, defining each unit meeting the conditions as a state node of a working condition response Markov chain, and creating a state attribute record for each state node; pairing units which fall into adjacent two moments based on the time stamp sequence, recording state transfer, counting occurrence frequencies of all directed transfer, and constructing a state transfer frequency matrix; and carrying out row normalization processing on the state transition frequency matrix to obtain a state transition probability matrix, calculating a condition response change vector, and packaging a state node set, the state transition probability matrix, the condition response change vector set and a state attribute record set to form a working condition response Markov chain integral object.
5. The method for proportioning biomass gasification coupled coal-fired power generation according to claim 1, wherein the step of generating a proportioning feedforward control function set comprises: Taking the biomass blending proportion and the coal fines fineness parameter as control variables, and setting a group of candidate control combinations for each state node in a working condition response Markov chain; For each group of candidate control combinations, carrying out multi-step forward simulation on the chain by using the transition probability of the working condition response Markov chain, and predicting a state sequence accessed in a limited step and corresponding gas heat value fluctuation, tar enrichment trend and boiler load change; And comprehensively quantifying and evaluating the forward simulation result, the safety constraint, the efficiency target and the environmental protection index, screening a group of optimal control strategies for each state node, and constructing a proportioning feedforward control function set.
6. The method for matching raw material characteristics to biomass gasification coupled coal-fired power generation proportioning of claim 5, wherein the step of performing multi-step forward simulation comprises: defining an upper limit of forward simulation steps, starting an independent forward simulation process for each candidate control combination of each state node, and initializing the current state, the gas heat value, the tar content and the boiler load; the simulation process follows the random walk rule of the Markov chain, samples and determines the next state node in each step, updates relevant parameters by using the condition response change vector, repeats the transfer and update process until reaching the upper limit of the number of steps or entering the absorption state, and records the simulation track; Repeatedly executing the Monte Carlo simulation for each candidate control combination for a plurality of times, aggregating simulation results, calculating relevant statistics, and storing the relevant statistics in a forward simulation result database.
7. The method for matching raw material characteristics to biomass gasification coupled coal-fired power generation proportioning of claim 6, wherein the step of realizing feedforward and feedback cooperative adjustment comprises the steps of: The fuel main control loop adopts a cascade control structure to realize the matching of biomass and pulverized coal feeding quantity, the air supply control loop adopts a cross limiting control logic to ensure the adaption of total air supply quantity and fuel quantity, the induced air control loop maintains the micro negative pressure of the hearth pressure, and the proportional feedforward compensation is carried out according to the air supply quantity; Calculating a feedback correction amount based on the hearth temperature and the oxygen feedback signal, and superposing the feedback correction amount on a feedforward set value; When the state is switched due to the abrupt change of the raw material batch, the control system rapidly switches the control strategy, the set value slope is adopted for transition, the model parameters of the feedback compensation module are reconstructed on line, and the feedforward and feedback cooperative disturbance suppression is realized.
8. A raw material property adaptation biomass gasification coupled coal-fired power generation proportioning system for implementing the method of any of claims 1-7, characterized in that the system comprises: The raw material characteristic data acquisition and phase space grid construction module is used for acquiring on-line and laboratory analysis data of biomass and coal raw materials, constructing a unified characteristic coordinate system and discretizing to generate a raw material characteristic phase space grid; The working condition response Markov chain construction module is used for fusing gasification products and boiler combustion online monitoring data and constructing a working condition response Markov chain along a time evolution path of the raw material characteristic phase space grid; The proportioning feedforward control function set generating module is used for carrying out forward simulation and multi-objective optimization based on a working condition response Markov chain to generate a proportioning feedforward control function set; And the control execution and cooperative adjustment module is used for embedding the proportioning feedforward control function set into the automatic control system, calling a corresponding function according to the real-time state, and combining a feedback signal to realize the dynamic adjustment of the proportioning of biomass and fire coal and the combustion working condition.

Description

Method and system for matching raw material characteristics with biomass gasification coupling coal-fired power generation ratio Technical Field The invention relates to the technical field of coal-fired power generation, in particular to a method and a system for matching raw material characteristics with biomass gasification coupling coal-fired power generation. Background The biomass gasification coupling coal-fired power generation technology is an energy utilization mode combining biomass energy and coal-fired power generation, and aims to consider renewable energy utilization and power generation system stability and realize clean and efficient energy conversion. The existing fuel mixing and proportioning method mainly determines the mixing proportion of biomass and coal according to basic industrial analysis data of raw materials or experience accumulated in long-term operation, and cooperates with a conventional control loop of a gasification furnace and a boiler to perform feedback adjustment on fuel feeding quantity by monitoring operation parameters such as hearth temperature, flue gas oxygen quantity, flue gas temperature and the like so as to maintain the basic stability of gasification and combustion processes. The operation flow of the proportioning technology is relatively fixed, depends on preset proportioning rules or single heat value index, and is suitable for operation scenes with concentrated raw material sources and small characteristic fluctuation. However, the existing fuel mixing and proportioning method has obvious limitations. Industrial analysis indexes such as volatile matters, moisture, ash and the like of biomass raw materials are susceptible to dynamic fluctuation due to factors such as regional differences, seasonal changes, storage conditions and the like, and the indexes have nonlinear strong coupling relation with combustible gas components generated by gasification, tar generation amount and combustion reaction characteristics, and are further modulated by the fixed carbon content and particle characteristics of coal dust in the co-combustion process of the indexes and the coal dust, so that a complex multivariable interaction relation is formed. The existing proportioning strategy can not effectively identify the complex coupling relation, lacks a targeted online adaptation mechanism, only depends on the lagged operating parameters such as the temperature, the oxygen content and the like of a hearth to carry out feedback adjustment, and can not dynamically reconstruct the optimal blending proportion according to the characteristic change of raw materials before the fuel enters the furnace. The gasification product heat value is unstable, the combustion reaction in the boiler is unbalanced, the fuel is not combusted sufficiently, the unburnt carbon content is increased, the temperature fluctuation of a hearth is triggered, the heat exchange uniformity of a heating surface is affected, the local loss of equipment can be aggravated after long-term operation, and the system protection shutdown can be triggered due to the fact that the fluctuation of working conditions exceeds a control range when serious. The characteristics of a certain power station are changed due to the change of the biomass raw material storage environment, the fuel ratio is not adjusted in time, so that the components of the combustible gas generated by gasification are fluctuated, the combustion stability of a boiler is reduced, high-temperature corrosion signs appear in a local area of a hearth, the load of a unit is forced to be reduced for shutdown inspection, and the power generation loss and the overhaul cost are increased. Disclosure of Invention In order to overcome the defects in the prior art, the invention provides a method for matching the characteristics of raw materials with the gasification coupling coal-fired power generation ratio of biomass, which comprises the following steps: collecting online and laboratory analysis data of biomass and coal raw materials, constructing a unified characteristic coordinate system, discretizing, and generating a raw material characteristic phase space grid for representing batch and time variation; Fusing gasification products and on-line monitoring data of boiler combustion, and constructing a working condition response Markov chain along a time evolution path of a raw material characteristic phase space grid; Based on a working condition response Markov chain, forward simulation is carried out on state transition under different blending assumptions, and a proportion feedforward control function set for giving fuel proportion and auxiliary control quantity for each state is generated; The proportioning feedforward control function set is embedded into the automatic control system of the fuel feeding and the boiler, the corresponding function is called according to the state recognized in real time, and the dynamic adjustment of the proportioning of