Yang X.,Zhejiang University |
Gong G.-F.,Zhejiang University |
Yang H.-Y.,Zhejiang University |
Jia L.-H.,China Railway Engineering Equipment Group Co. |
Ying Q.-W.,Hangzhou Boiler Group Co.
Journal of Zhejiang University: Science A | Year: 2015
In this paper, we propose a shield cutterhead load characteristic forecast method and apply it to optimize the efficiency of the cutterhead driving system. For the forecast method, wavelet transform is used for preprocessing, and grey model GM(1,1) for forecasting. The performance of the wavelet-based GM(1,1) (WGM(1,1)) is illustrated through field data based load characteristic prediction and analysis. A cutterhead mode control strategy (CMCS) is presented based on the WGM(1,1). The CMCS can not only provide operators with some useful operating information but also optimize the stator winding connection. Finally, the CMCS is tested on a cutterhead driving experimental platform. Results show that the optimized stator winding connection can improve the system efficiency through reducing the energy consumption under part-load conditions. Therefore, the energy-saving CMCS is useful and practical. © 2015, Zhejiang University and Springer-Verlag Berlin Heidelberg.
Zhu H.,Hangzhou Dianzi University |
Chen W.,Hangzhou Boiler Group Co. |
Jiang X.,Zhejiang University |
Yan J.,Zhejiang University |
Chi Y.,Zhejiang University
Frontiers of Environmental Science and Engineering | Year: 2014
Under both pyrolysis and combustion condition, HCl removal efficiency for medical waste with Cabased additives was semi-quantitatively studied by means of TG-FTIR. Additionally, the difference of HCl removal efficiency for PVC and medical waste was compared. Experimental results showed that: 1) Thermal degradation of medical waste mainly took place in two steps under both pyrolysis and combustion condition; 2) HCl emitted at both two steps and HCl concentration increased with the increased of Cl ratio in the medical waste; 3) for the same additive, HCl concentration decreased with the increased of additives amount, that is to say, HCl removal efficiency of medical waste increased as the increased of Ca/Cl molar ratio. Fourth, when Ca(OH)2 was used as additive, HCl removal efficiency for medical waste combustion was a little higher than that for medical waste pyrolysis, but either CaCO3 or CaO was used as additive, it was just opposite, more specifically, when CaCO3 was used as additive with Ca/Cl = 1.3, HCl removal efficiency was 5.49% under pyrolysis condition, but that was only 4.24% under combustion condition. Fifth, under the same Ca/Cl molar ratio, HCl removal efficiency for PVC was higher than that for medical waste under both pyrolysis and combustion condition, more specifically, when Ca(OH)2 was used as additive with Ca/Cl = 1, HCl removal efficiency was 64.51% for PVC, but that was only 27.66% for medical waste pyrolysis with 4% Cl under pyrolysis condition. © 2014 Higher Education Press and Springer-Verlag Berlin Heidelberg.
Han Z.,China Jiliang University |
Chi Z.,China Jiliang University |
Wang J.,China Jiliang University |
Zhang G.,China Jiliang University |
And 2 more authors.
Dongli Gongcheng Xuebao/Journal of Chinese Society of Power Engineering | Year: 2015
Cold-state experiments were performed to the no-hook, single-hook and double-hook corrugated-plate separator in the drum of waste heat boiler, so as to study the total separation efficiency, single-stage separation efficiency, inlet droplet size, outlet droplet size and the resistance coefficient at different inlet air velocities. Results show that the corrugated-plate separator with double hooks has the highest total separation efficiency among all the three separators, and their critical film-breaking velocities are 2 m/s, 5 m/s and 7 m/s, respectively; for both the no-hook and double-hook corrugated-plate separator, the single-stage separation efficiency at first three stages is far more than at last three stages; for the single-hook corrugated-plate separator, the single-stage separation efficiency increases significantly at the last three stages with the rise of inlet air velocity, especially at the sixth stage; for all the three separators, the outlet droplet size rises quickly at the critical film-breaking velocity; the resistance coefficient of single-hook corrugated-plate separator is far greater than that of no-hook and double-hook one. Based on overall consideration, the double-hook corrugated-plate separator is proved to have the best performance among all the three types. ©, 2015, Shanghai Power Equipment Research Institute. All right reserved.
Zhang G.-X.,China Jiliang University |
Chi Z.-H.,China Jiliang University |
Zhou C.-H.,Hangzhou Boiler Group Co. |
Chen W.-Y.,Hangzhou Boiler Group Co. |
Zhao J.-Y.,Hangzhou Boiler Group Co.
Dongli Gongcheng Xuebao/Journal of Chinese Society of Power Engineering | Year: 2012
To overcome the frequent shutdown problem occurring in waste heat power generation caused by unstable operation of the sintering machine in the steel plants, a supplemental burner was designed for a 400 m 2 sintering waste heat boiler, in which the supplemental combustion and gas distribution were numerically simulated. Results show that by taking blast furnace gas as the main fuel and coke oven gas as the auxiliary fuel, the supplemental burner, installed in the inlet flue duct of waste heat boiler, can help to raise the flue gas temperature by 60-140 K; the temperature in supplemental combustion chamber may get up to 1500°C, while the outlet temperature of flue gas can get to about 1120°C and outlet volumetric fraction of CO keep at 0.15%, showing a high burn-off rate.