Entity

Time filter

Source Type


Gao M.,Tsinghua University | Gao M.,North China Electrical Power University | Yue G.,Tsinghua University | Lei X.,Sichuan Baima CFB Demonstration Power Plant Co. | And 3 more authors.
Dongli Gongcheng Xuebao/Journal of Chinese Society of Power Engineering | Year: 2015

By analyzing the dynamic characteristics, energy balance, burning carbon and main steam pressure control of supercritical circulating fluidized bed (CFB) boilers, a soft-sensing model was established based on mechanism analysis by reasonably setting relevant key parameters, so as to calculate the amount of burning carbon storage and heat storage in the furnace, and thus obtaining the heat signal in the boiler. The control strategy of energy balance was then applied in the main steam pressure control of a supercritical CFB boiler. Results show that the method can help to stabilize the main steam pressure, enhance the adaptability to load change and improve the control quality of the unit, proving both the model established and the method proposed to be effective. ©, 2015, Shanghai Power Equipment Research Institute. All right reserved. Source


Gao M.,Tsinghua University | Gao M.,North China Electrical Power University | Yue G.,Tsinghua University | Lei X.,Sichuan Baima CFB Demonstration Power Plant Co. | And 3 more authors.
Dongli Gongcheng Xuebao/Journal of Chinese Society of Power Engineering | Year: 2014

For the instable and time delay process of in-furnace desulfurization in circulating fluidized bed (CFB) boiler, a specific "active limestone" state monitoring model was set up to simulate the desulfurization process, while a method for optimization of the n(Ca)/n(S) was suggested according to the balance of "active limestone", and simultaneously a SO2 emission prediction model was proposed based on the coal feed rate, air flow rate and in-furnace active limestone mass, with which simulation tests were carried out to a 600 MW supercritical CFB boiler using actual operation data. Simulation results prove the prediction model to be effective, and the optimization of n(Ca)/n(S) based on the model helps to improve the stability of SO2 emission. Source


Gao M.-M.,North China Electrical Power University | Liu J.-Z.,North China Electrical Power University | Niu Y.-G.,North China Electrical Power University | Lei X.-J.,Sichuan Baima CFB Demonstration Power Plant Co. | And 2 more authors.
Dongli Gongcheng Xuebao/Journal of Chinese Society of Power Engineering | Year: 2013

To overcome the deficiency of delayed heat release signals from circulating fluidized bed (CFB) boiler, a method was put forward for calculation of the heat release and carbon residue by using easily measured signals of the combustion process. The specific way is to firstly divide the combusion system into dense phase area, dilute phase area and adiabatic cyclone separator area, then calculate the combustion share in adiabatic cyclone separator area based on materials mass and heat balance model, and finally build up carbon residue model by mechanism analysis and heat release model according to carbon residue and air volume. Based on experimental data of a 300 MW CFB boiler, and using extended Kalman filter technology, the in-furnace carbon residue and heat release were calculated respectively at loads of 285 MW and 200 MW, of which the results were compared with relevant literature data. Results show that the calculated results basically agree with relevant literature data, proving the model to be accurate and reasonable. Source


Xia Y.-Q.,Southwest University of Science and Technology | Yan Y.,Southwest University of Science and Technology | Hu Z.-H.,Southwest University of Science and Technology | Hu C.-H.,Sichuan Baima CFB Demonstration Power Plant Co. | Lei X.-J.,Sichuan Baima CFB Demonstration Power Plant Co.
Wuhan Ligong Daxue Xuebao/Journal of Wuhan University of Technology | Year: 2012

The pozzolanic and self-cementitious properties of CFBC fly ash with various chemical activators were investigated. The effect of different chemical activators and their different combinations on the mechanical properties of CFBC fly ash was evaluated based on the criteria of 7 d and 28 d compressive strengths of CFBC fly ash. Meanwhile, the influence of chemical activators on the early hydrating process and hydrated products of CFBC fly ash were analyzed with isothermal calorimeter method, XRD and IR. The results show that different activators obviously affect the strength of hardened CFBC fly ash paste and the degree of impact in order is as follows: lime>sodium silicate>TEA>Na2SO4; the addition of Na2SO4 promotes the dissolution of anhydrite and increases its hydration rate, composite activation of Na2SO4and TEA can solve the question that compressive strengths of CFBC fly ash with adding Na2SO4 increases slowly; the addition of lime significantly improves the activity of CFBC fly ash; the combination of four activators mentioned above are recommended to use for increasing the activity of CFBC fly ash, resulting into the 7 d and 28 d compressive strength of the mortar is up to 7 MPa and 22 MPa, respectively. Source


Sun J.,National School of Technology | Wang Z.,Tsinghua University | Cao W.,National School of Technology | Wu H.,Tsinghua University | And 3 more authors.
Flow, Turbulence and Combustion | Year: 2013

An improved two particle sizes numerical model based on a uniform size model was established to investigate the influence of the average particle size on bed-inventory overturn inside a pant-leg circulating fluidized bed (CFB). The new model successfully simulated the dynamic performance of a pant-leg CFB that as average particle size shrank, the pant-leg CFB tended to overturn, while the uniform size model showed a contradicted trend. The success was attributed to the difference of the flow pattern with different particle size. The smaller particles tend to stay the upper furnace after fluidized by the primary air flow while the larger particles tend to fall back to the bottom soon after being carried to upper furnace by the primary air flow and smaller particles. As pointed out in our previous work, the lateral mass transfer resulted in a lateral pressure difference at the upper finance and inhibited further lateral mass transfer, which was regarded as a self-balancing process. The quick fall down of the large particles somehow weaken the lateral pressure different built-up at the upper furnace. Therefore, as the average particle size shrink, the weaken effect of the large particles on self-balancing ability of the pant-leg CFB increase, resulting a more tendency for bed-inventory overturn. It was such a characteristic behavior of the large particles, which was neglected in the uniform particle size model, caused the difference between the results of the two models described above. © 2013 Springer Science+Business Media Dordrecht. Source

Discover hidden collaborations