591 results about "Boiler efficiency" patented technology

The present invention harvests and utilizes fluidized bed drying technology and waste heat streams augmented by other available heat sources to dry feedstock or fuel. This method is useful in many industries, including coal-fired power plants. Coal is dried using the present invention before it goes to coal pulverizers and on to the furnace/boiler arrangement. Coal can be intercepted on current coal feed systems ahead of the pulverizers. Drying fuel, such as coal, is done to improve boiler efficiency and reduce emissions. A two-stage bed utilized in the process first “pre-dries and separates” the feed stream into desirable and undesirable feedstock. Then, it incrementally dries and segregates fluidizable and non-fluidizable material from the product stream. This is all completed in a low-temperature, open-air system. Elevation of fan room air temperature is also accomplished using waste heat, thereby making available to the plant system higher temperature media to enhance the feedstock drying process.

The invention provides a large coal-fired unit online monitoring and optimal control system and an implementation method thereof. The method includes the steps of analyzing combustion characteristics of a boiler of a large coal-fired unit, and performing boiler combustion optimization and adjustment test to acquire boiler operation key parameters; determining a relation of the boiler operation key parameters to boiler efficiency and NOx emission, and establishing an optimal control model according to the relation; training the optimal control model to obtain specific optimal values of boiler operation parameters under highest boiler efficiency. The large coal-fired unit online monitoring and optimal control system and the implementation method thereof have the advantages that boiler efficiency is improved on the premise of guaranteeing low NOx emission and operational economy of power plants is effectively improved.

The invention discloses a boiler combustion optimizing control system and a boiler combustion optimizing control method. The method comprises the following steps of: on the basis of the equilibrium distribution and transformation for coal powder in a fire coal unit, accurately measuring parameters such as wind, powder, ash and the like by using a measuring device; analyzing a history behaviour of operation by the deep analysis and digging of data by using the acquired real-time history data of a boiler and taking the work condition optimization as a basic optimizing method; establishing mathematical models among operation parameter, status input parameter and parameters such as boiler efficiency, NOx and the like in the combustion process to obtain a unit operation mode knowledge base; performing the whole plant energy-saving and emission-reducing comprehensive assessment and diagnosis; analyzing the unit operation potential; and providing a knowledge base and a rule for optimizing operation; optimizing boiler combustion parameter configuration aiming at different combustion indexes or an index combination to realize the optimization of multiple optimizing objects and propose an energy-saving and emission-reducing implementation scheme and measurement in a classification mode. The method not only can realize closed-loop optimizing control but also can realize on-line optimizing guide.

The invention discloses a method for coordinating and controlling quality change of coal in a supercritical once-through boiler unit. The method is used for building a boiler master control provided with balanced indirect energy, and comprises the following steps: quantifying coal quantity by load; quantifying primary air quantity by the coal quantity; confirming a dominant role of instructions of the boiler master control; jointly debugging the ratios of wind, water and coal to ensure that the superheat degree of the boiler meets the requirement; meanwhile, ensuring the control precision of the front pressure of the boiler unit to meet the requirements of a power grid for changing range and speed rate. The method mainly solves the problem that the unit runs fast while the boiler efficiency is low, and builds a novel static feedforward, a load dynamic feedfoward, a pressure dynamic feedforward, and dynamic corrections of the feedforwards based on quality change of coal; the linkage of wind, water and coal quickens the responsiveness of the boiler; the joint debugging of water and coal solves the problem of quality change of coal, realizes the decoupling of water and coal and the decoupling of main steam pressure and superheat degree; the linear real-time coefficient modifies various experience curves; and a main steam pressure regulator of the boiler master control is subjected to the variable parameter control.

The invention provides a method and system for optimizing and controlling combustion performance of a circulating fluidized bed boiler in real time. The method for optimizing and controlling combustion performance of the circulating fluidized bed boiler in real time includes the steps that based on historical data of combustion of the boiler, a first neural network used for being matched with a nonlinear mapping relation between the input and the output of an existing fluidized bed boiler system is established; according to the first neural network, the adjustable input variable of the input of the fluidized bed boiler system is determined; and the adjustable input variable serves as the bottom layer control input, the trends of corresponding deviation and the deviation change rate are calculated, and a second neural network is established for training and acquiring the process variable control output. By the adoption of the method and system, the boiler efficiency is improved, the power supply coal consumption is lowered, coking and slag bonding are prevented or treated, NOx emission is reduced, and the safety, the reliability and the economical efficiency of operation of the boiler are further improved.

The invention relates to a synchronous reckoning method of utility boiler efficiency and coal heat value as well as ash content and moisture content, wherein air supply temperature, smoke exhaust temperature, smoke exhaust oxygen content, carbon content in fly ash, boiler-fed fuel content, boiler evaporation amount, assembly electric generating load, main steam pressure temperature, reheated steam inlet/outlet pressure temperature, water supply pressure temperature and flow rate, steam drum pressure, reheater temperature lowering water jet amount and steam extraction pressure temperature of each heater of high pressure cylinder are read through a plant-level supervisory information system (SIS) of a thermal power plant; and the parameters as the water temperature and drainage temperature of the inlet/outlets of different-level heaters of the high pressure cylinder are synchronously reckoned by hypothesizing the initial values of the coal heat value, the coal ash content and the coal moisture content, utilizing a boiler anti-balance heat efficiency model, a dry air amount required for theoretical combustion and actual smoke quality simplified calculating model, an actual smoke quality calculating model, an actual smoke volume calculating model, an actual smoke amount calculating model, a boiler positive-balance heat efficiency model and a boiler effective utilized heat model, and establishing prediction and rectification methods.

The invention discloses a fluidized bed boiler control and combustion optimization system. The problem that a fluidized bed boiler system is not easy to control for a long time is solved. According to a method, a control strategy of combining an advanced control algorithm and a conventional control algorithm is adopted, and continuous, economical and stable operating of the boiler system is guaranteed; multivariable model-free adaptive control is adopted, and decoupling control of the fuel quantity and the air supply quantity over the bed temperature under the variable load work condition is achieved; and a nerual network technique is adopted for building a boiler combustion prediction model, online calculation of the boiler efficiency and NOX and SOX emissions is achieved, a multi-objective optimization function is constructed according to the prediction result, a combustion self-optimization algorithm is adopted, the flue gas oxygen content and the bed temperature are optimized constantly so as to adapt to work condition changes, and a fluidized bed boiler can operate in an optimal combustion area.

Provided is a boiler combustion optimization air distribution method based on online model prediction. The method includes: constructing a boiler combustion optimization air distribution model by employing an improved BP neural network algorithm and model online update calculation; and performing optimization calculation on parameters such as the optimal oxygen amount, the primary air amount, each secondary air door and a burnout air door etc. with the combination of an adaptive genetic algorithm and dynamic optimization boundary so that a multi-target function constructed by the boiler efficiency and the pollutant discharge capacity reaches the optimal combustion range.

The invention relates to an integrated system for utilizing residual heat of boiler smoke and removing sulfur. A tubular heat exchanger is used as a heat exchange main body of the system and is arranged on a tail flue between a booster fan and a desulfurization absorber, wherein the tubular heat exchanger is connected to a condensed water heating system; sets of nozzles are arranged in the heat exchanger for intermittently washing the inner tube wall of the heat exchanger and the wall of the flue; the processing water from a desulfurization system or limestone size or the mixture of the processing water and the limestone size are used as washing fluid for washing the walls; and the washing fluid is recovered and reused by returning to the desulfurization absorber after gathering on the bottom of the heat exchanger. By using the integrated system provided by the invention, the temperature of the smoke on the tail part of the boiler can be reduced to 50-70DEG C, thereby recovering the residual heat of boiler smoke and increasing the boiler efficiency. Meanwhile, the smoke within the temperature range which enters into the absorber of the desulfurization system on the tail part still meets the requirement of the temperature for desulfurization reaction, and the water consumption for desulfurization is reduced by 50-80%. Without designing a single size preparation and sewage treatment process, the water-saving and energy-saving properties, the anticorrosion property and reuse of the whole system are finally realized.

An integrated sorbent injection, heat recovery, and flue gas desulfurization system is disclosed. A dry sorbent is injected into the flue gas upstream of the air heater. This reduces the acid dew point temperature, permitting additional heat energy to be captured when the flue gas passes through the air heater. The flue gas then passes through a desulfurization unit and through a baghouse, where solids are captured. The capture of additional heat energy permits the overall boiler efficiency to be increased while safely operating at a lower flue gas temperature. The integrated system consumes no greater quantity of sorbent than conventional methods but provides the benefit of improved plant heat rate.

The operation of a fossil-fueled thermal system is quantified by obtaining an unusually accurate boiler efficiency. Such a boiler efficiency is dependent on the calorimetric temperature at which the fuel's heating value is determined. This dependency affects the major thermodynamic terms comprising boiler efficiency.

The invention provides an energy efficiency analysis method of a generator set. The method comprises: acquiring generator set parameters, set performance target value and actual values; calculating external condition deviations according to boiler actual coal consumption, current environment temperature, turboset circulating water temperature, turboset heat-supply power generation ratio and turboset power generation capacity of the generator set parameters; respectively calculating a boiler efficiency deviation, a turboset efficiency deviation and a station service power consumption rate deviation through a boiler performance test, a turboset performance test and station service power consumption rate testing performance test under multiple working conditions, and calculating a device performance deviation according to the boiler efficiency deviation, the turboset efficiency deviation and the station service power consumption rate deviation; calculating expected values of set actual operation according to generator set design parameters, the external condition deviations and the device performance deviation; and respectively calculating difference values between the expected values and the target values and difference values between the expected values and the actual values, and calculating generator set energy efficiency according to preset weights and corresponding membership functions of the two types of difference values.

The invention discloses a boiler efficiency self-correction computing method based on flue gas testing. The boiler efficiency self-correction computing method comprises the following steps: (1) transmitting all primary measurement signals of a unit to a built data platform through Internet network in real time, carrying out online monitoring, and processing the data on the platform to obtain and compute parameters required by the boiler efficiency; (2) conducting online flue gas testing, transmitting the data signals to the data platform through the Internet network in real time, and processing the data; (3) meanwhile, from the aspect of positive balance and negative balance, regarding the acquired primary measurement values, secondary parameters obtained by computing the primary measurement values and parameters obtained by the field flue gas testing as known quantities, and establishing a boiler efficiency real-time monitoring mathematical model. The method is simple, convenient, feasible and suitable for variable coal quality operation conditions, and realizes real-time online measurement and self-correction of boiler thermal efficiency, fire coal analysis, fire coal calorific value and various heat losses of the boiler.

The invention discloses a method for calculating coal elements and industrial components in real time, which comprises the following steps of: acquiring the boiler total heat absorption capacity by utilizing the existing calculation results and acquired real-time data; calculating a real-time calorific value of coal as fired by utilizing the real-time coal supply; and calculating elements, moisture and ash of the actual coal as fired in real time by utilizing designed coal elements and industrial components. The coal parameter acquired by the method can also be used for calculating boiler efficiency and coal consumption of thermal power units in real time.

The present invention discloses a power station boiler low NOx combustion method based on wind powder closed loop control and a boiler primary air wind powder closed loop control system. The method is as follows: the main burner region excessive air coefficient is controlled below 1.0; the deficient air at the upper side of a hearth is supplemented by an SOFA nozzle at AA interval; a function f(Q)=f(N,D) is used to compare NOx actual measured value with target value, wherein N is coal type, D is load and Q is graded air amount; after adjusted by PID, the deviation of the comparison is used as a correcting factor to be overlapped with the coal type-load-graded air amount function f(Q) for adjusting the mixture ratio between the SOFA air amount and the secondary air amount of the combustion region. The system comprises a first signal measuring part, a signal acquiring part, a data processing part and a feedback part. With the closed loop control system, the method ensures, in different working conditions, the even distribution of the first air wind powder of each layer and perfect mixture ratio between the SOFA air amount and the secondary air amount of the combustion region, so that the method realizes the optimized control target of reducing the discharging of boiler contamination NOx and improving boiler efficiency.

The utility model discloses a combustion device for a tangentially fired boiler and an ultralow NOx combustion method employing same. A high-position burner, a low-position burner and a main burner are arranged on a hearth from top to bottom; the space between the low-position burner and the main burner is H2, the main burner comprises dense-dilute primary air pulverized coal burners and secondary air pulverized coal burners arranged at the upper parts and the lower parts of the dense-dilute primary air pulverized coal burners, wherein the secondary air pulverized coal burners correspond to secondary air nozzles, the dense-dilute primary air pulverized coal burners are bifurcated pipes, light-phase primary air nozzles and dense-phase primary air nozzles are arranged at the front ends of the bifurcated pipes respectively, and middle secondary air nozzles are arranged between the light-phase primary air nozzles and the dense-phase primary air nozzles; and the main burner comprises an upper group of burners and a lower group of burners, and the space between the upper group of burners and the lower group of burners is H1. The characteristic of divided layer blowing in the horizontal direction is reflected, mixing the secondary air is delayed, the purpose of supplying air on the same layer by grading is achieved, mixing O2 is delayed, the production of NOx is inhibited, and the efficiency of the boiler is ensured not to be reduced.

This invention is an emission control system wherein the boiler hosts a reactor which contains one or more catalysts for the purpose of reducing NO_x and/or CO in the emissions. The reactor containing the NOx/CO catalysts may be placed at a place where the temperature is in the range of 300-1000° F. The hot flue gas can be diverted using control dampers and blended with colder flue gas inside the boiler to achieve the desired flue gas temperature for the selected catalyst. NO_x is removed by the SCR catalyst inside the boiler upon injecting a suitable reducing agent (e.g. ammonia, or hydrocarbons). The CO and NO_x catalysts may be used in any order. The emission control system is an integral part of the boiler, and the existing capabilities of the boiler to recover the heat from flue gas, after the catalyst layers, is utilized such that the overall boiler efficiency remains high.

The invention relates to a method for optimizing a load distribution of a boiler. At present, the concept of load distribution optimization has not been provided. The method comprises the steps of respectively acquiring load and boiler efficiency data corresponding to the load in the production process of boilers in the production unit of the number of boilers of n (n is greater than 1), establishing a database, modeling each boiler by using a support vector machine method, establishing the model between the load of each boiler and the combustion efficiency, establishing n models, and optimizing the load configuration of each boiler by using a genetic optimization algorithm and combining the boiler load and the combustion efficiency model. By the method, the load of boilers can be distributed through optimization in case that the total load is certain, and the total combustion efficiency is improved.