Flue Gas Outlet Temperature Research Articles

A novel approach for modelling of NOx emission reduction in a tangentially fired coal boiler

In this research paper, predictive modelling of NOx emission of a 210 MW capacity pulverised coal-fired boiler and combustion parameter optimisation to reduce NOx emission in flue gas is proposed. The effects of oxygen concentration in flue gas, coal properties, coal flow, boiler load, air distribution scheme, flue gas outlet temperature and nozzle tilt were studied. The data collected from parametric field experiments were used to build a feed-forward back-propagation artificial neural net (ANN). The coal combustion parameters were used as inputs and NOx emission as outputs of the model. The ANN model was developed for full load condition and its predicted values were verified with the actual values. The algebraic equation containing weights and biases of the trained net was used as fitness function in sequential quadratic programming (SQP) and genetic algorithm (GA) to find the optimum level of input operating conditions for low NOx emission. The results proved that the proposed approach could be used for generating feasible operating conditions.

Numerical Simulation of the Flue Gas and Process Side of Coking Furnaces

A numerical simulation for the flue gas and process sides of a coking furnace with floor gas burners was conducted. The computational fluid dynamics (CFD) approach was employed to simulate flow, combustion, and heat transfer in the furnace. The process-side conditions were calculated with a special program. The simulation provides detailed information about the flue gas velocity, temperature fields, and process conditions for this type of coking furnace. Good agreement is obtained between industrial measurement and simulated excess air coefficient, outlet temperature of flue gas, and outlet pressure on the process side. Moreover, the simulated results indicate that there are hot spots on the tubes, located at the height of 1.5–2.5 m. That is consistent with the actual phenomenon of industrial coking furnaces. To investigate the effect of furnace structure on physical field distribution and process-side conditions, a comparative simulation case with more wide spacing of burners to walls was conducted. Resu...

ANN - SQP Approach For NOx Emission Reduction In Coal Fired Boilers

Abstract In this research paper, predictive modelling of NOx emission of a 210 MW capacity pulverized coal-fired boiler and combustion parameter optimization to reduce NOx emission in flue gas is proposed. The effects of oxygen concentration in flue gas, coal properties, coal flow, boiler load, air distribution scheme, flue gas outlet temperature and nozzle tilt were studied. The data collected from parametric field experiments were used to build a feed-forward back-propagation artificial neural net (ANN). The coal combustion parameters were used as inputs and NOx emission as outputs of the model. The ANN model was developed for full load condition and its predicted values were verified with the actual values. The algebraic equation containing weights and biases of the trained net was used as fitness function in sequential quadratic programming (SQP) to find the optimum level of input operating conditions for low NOx emission. The results proved that the proposed approach could be used for generating feasible operating conditions.

ANN–GA approach for predictive modeling and optimization of NOx emission in a tangentially fired boiler

An artificial neural network (ANN) and genetic algorithm (GA) approach to predict NOx emission of a 210 MW capacity pulverized coal-fired boiler and combustion parameter optimization to reduce NOx emission in flue gas, is proposed. The effects of oxygen concentration in flue gas, coal properties, coal flow, boiler load, air distribution scheme, flue gas outlet temperature, and nozzle tilt were studied. The data collected from parametric field experiments was used to build a feed-forward back-propagation neural net. The coal combustion parameters were used as inputs and NOx emission as outputs of the model. The ANN model was developed for full load conditions and its predicted values were verified with the actual values. The algebraic equation containing weights and biases of the trained net was used as fitness function in GA. The genetic search was used to find the optimum level of input operating conditions corresponding to low NOx emission. The results proved that the proposed approach could be used for generating feasible operating conditions.

Predictive modelling and optimization of nitrogen oxides emission in coal power plant using Artificial Neural Network and Simulated Annealing

In this research paper, predictive modelling of NOx emission of a 210 MW capacity pulverized coal-fired boiler and combustion parameter optimization to reduce NOx emission in flue gas is proposed. The effects of oxygen concentration in flue gas, coal properties, coal flow, boiler load, air distribution scheme, flue gas outlet temperature and nozzle tilt are studied. The data collected from parametric field experiments are used to build a feed-forward back-propagation artificial neural net (ANN). The coal combustion parameters are used as inputs and NOx emission as outputs of the model. The ANN model is developed for full load condition and its predicted values are verified with the actual values. The algebraic equation containing weights and biases of the trained net is used as fitness function in simulated annealing (SA) to find the optimum level of input operating conditions for low NOx emission. The result proves that the proposed approach could be used for generating feasible operating conditions. DOI: http://dx.doi.org/10.11591/ij-ai.v1i1.286 Full Text: PDF

Analysis of the Method for Furnace Thermal Calculation with Radiation Intensity Attenuation

Based on the network method for radiant heat transfer, a radiant space resistance ke R /4F1 was proposed, the radiant heat transfer network diagrams which subjects to the radiation attenuation was given in this paper, this method is helpful to accurately analyze the zero-dimensional radiant heat transfer. Simulation results show that, due to the radiant space resistance kR /4F, the total thermal resistance between the flame and the water wall surface is degraded, radiation attenuation from the flame center to water wall surface should not be ignored. It is also shown that,when the radiation attenuation is involved, the furnace outlet flue gas temperature utilizing the furnace ɛf syn blackness is more accurate than the Soviet Union 1973 calculation standard.

The Energy-Saving Optimization of the Organic Heat Transfer Material Heater

this paper studies the typical irreversible processes such as combustion and heat transfer with temperature difference based on the theory of thermodynamics, analyzes the influencing factors on exergy loss in irreversible processes, on the basis of this analysis, proposes the energy-saving optimization measures on design and operation management of the organic heat transfer material heater, and specially points out that in the design process, objective function can be constructed with the exergy loss as evaluation index to determine the outlet flue gas temperature of furnace and the flue gas temperature, and provides theoretical basis for the determination of design parameters.

A Model for Calculating the Outlet Flue Gas Temperature of FGD Absorption Tower

Theoretical model for calculating the outlet flue gas temperature of limestone-gypsum wet flue gas desulfurization (FGD) absorption tower is important for water consumption calculation. In this paper, the energy balance in the spray zone is analyzed and a model for calculating the outlet flue gas temperature of FGD absorption tower is proposed. An example computation of the outlet flue gas temperature of a typical 600MW class unit’s operation data is introduced, the result has verified the model. A further study of significance analysis has then been made to analyze and simplify the model.

99/04024 Suggestions for the refurbishment of a Greek lignite-fired power plant. Efficiency, costs, and operation aspects: Stamatelopoulos, G. N. et al. FACT (Am. Soc. Mech. Eng.), 1998, 22, (1), 185–191

The present paper outlines measures for the refurbishment of the Greek lignite-fired power plant Kardia and discusses their impact on the efficiency, the electricity generation costs and the operation of the plant. The power plants Kardia III and IV with an installed capacity of 300 NW{sub el} each were constructed in the late 70's in Northern Greece and still operate as base load units for the Public Power Corporation (PPC) of Greece. Several problems are detected during the operation of these two units concerning high flue gas outlet temperature--and consequently low boiler efficiency, poor electrostatic precipitator performance, high slagging tendency, fluctuating temperature field resulting unstable steam temperatures and a high percentage of leakage air. To improve the current situation PPC in collaboration with the National Technical University of Athens (NTUA) conducted a feasibility study to set the priorities and to select the most suitable measures for the refurbishment of these two units. Taking advantage of the international experience, the possible measures applicable in the case of brown coal fired units upgrade were collected, categorized and presented to PPC's management. The proposed measures were evaluated for the specific case of Kardia and then it was decided to further examine the followingmore » actions: Sealing of the boiler in order to minimize the amount of the leakage air, extension of the economizer followed by the replacement of one bled steam feed water preheater aiming at the decrease of the flue gas outlet temperature and optimization of the soot blowers operation. For these actions and using the process simulation program ENBIPRO, the expected benefits in terms of efficiency as well as the dimensions of the necessary additional heating surface and the influence of the rearrangement of the heating surfaces in the boiler on the water/steam cycle were calculated. The costs of the suggested actions were estimated together with the time frame for their implementation. Investment plans were put together and the pay back time for each alternative was evaluated. Based on the discussed feasibility study PPC initialized a closer collaboration with a steam generator construction company in order to include the refurbishment of Kardia III and IV to its investment planning program for the coming years.« less