Simulation of a CFB Boiler Integrated With a Thermal Energy Storage System During Transient Operation
FRONTIERS IN ENERGY RESEARCH
Authors: Stefanitsis, Dionisis; Nesiadis, Athanasios; Koutita, Konstantina; Nikolopoulos, Aristeidis; Nikolopoulos, Nikolaos; Peters, Jens; Stroehle, Jochen; Epple, Bernd
Abstract
In the current work, a transient/dynamic 1-dimensional model has been developed in the commercial software APROS for the pilot 1 MWthCFB boiler of the Technical University of Darmstadt. Experiments have been performed with the same unit, the data of which are utilized for the model validation. The examined conditions correspond to the steady-state operation of the boiler at 100, 80, and 60% heat loads, as well as for transient conditions for the load changes from 80 to 60% and back to 80%. Fair agreement is observed between the simulations and the experiments regarding the temperature profiles in the riser, the heat extracted by the cooling lances, as well as the concentration of the main species in the flue gases; a small deviation is observed for the pressure drop, which, however, is close to the results of a CFD simulation run. The validated model is extended with the use of a thermal energy storage (TES) system, which utilizes a bubbling fluidized bed to store/return the particles during ramp up/down operation. Simulations are performed both with and without the use of TES for the load path 100-80-60-80-100%, and the results showed that the TES concept proved to be superior in terms of changing load flexibility, since the ramp up and down times proved to be much faster, and lower temperature drops between the loads are observed in this case.
Artificial Intelligence-Based Emission Reduction Strategy for Limestone Forced Oxidation Flue Gas Desulfurization System
JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME
Authors: Uddin, Ghulam Moeen; Arafat, Syed Muhammad; Ashraf, Waqar Muhammad; Asim, Muhammad; Bhutta, Muhammad Mahmood Aslam; Jatoi, Haseeb Ullah Khan; Niazi, Sajawal Gul; Jamil, Ahsaan; Farooq, Muhammad; Ghufran, Muhammad; Jawad, Muhammad; Hayat, Nasir; Jie, Wang; Chaudhry, Ijaz Ahmad; Zeid, Ibrahim
Abstract
The emissions from coal power plants have serious implication on the environment protection, and there is an increasing effort around the globe to control these emissions by the flue gas cleaning technologies. This research was carried out on the limestone forced oxidation (LSFO) flue gas desulfurization (FGD) system installed at the 2*660 MW supercritical coal-fired power plant. Nine input variables of the FGD system: pH, inlet sulfur dioxide (SO2), inlet temperature, inlet nitrogen oxide (NOx), inlet O-2, oxidation air, absorber slurry density, inlet humidity, and inlet dust were used for the development of effective neural network process models for a comprehensive emission analysis constituting outlet SO2, outlet Hg, outlet NOx, and outlet dust emissions from the LSFO FGD system. Monte Carlo experiments were conducted on the artificial neural network process models to investigate the relationships between the input control variables and output variables. Accordingly, optimum operating ranges of all input control variables were recommended. Operating the LSFO FGD system under optimum conditions, nearly 35% and 24% reduction in SO(2)emissions are possible at inlet SO(2)values of 1500 mg/m(3)and 1800 mg/m(3), respectively, as compared to general operating conditions. Similarly, nearly 42% and 28% reduction in Hg emissions are possible at inlet SO(2)values of 1500 mg/m(3)and 1800 mg/m(3), respectively, as compared to general operating conditions. The findings are useful for minimizing the emissions from coal power plants and the development of optimum operating strategies for the LSFO FGD system.