257 publications from this institution
Pyrolysis of coal occurs in all coal conversion processes and is perhaps the most difficult to model mathematically. A number of models on coal pyrolysis have been proposed during the past several decades. However, very few of these models address the simultaneous changes in product distribution and particle weight loss (or conversion) over a wide range of operating conditions. Such a mathematical model which could take into consideration the effects of residence time, final temperature, heating rate and pressure is needed for design and scale-up of coal pyrolysis and gasification reactors. The purpose of this study is to develop such a mathematical model for simulation of the pyrolysis phenomena of a coal particle. The model to be developed should be general enough to be applicable to other pyrolysis systems such as the pyrolysis of wood.
Extensive research has been conducted on the replacement of steel rebars with fibre-reinforced polymer rebars to eliminate the steel corrosion problem in conventional steel bar–reinforced concrete ...
Water splitting driven by photo-induced oxygen vacancies for H 2 production was proved to be facile on metal doped CeO 2 .
The strong column/weak beam requirement is now widely accepted in the design of reinforced concrete (RC) frames to achieve good seismic performance. However, many existing RC frames violate this requirement as they were designed according to inadequate design codes (generally previous codes). In particular, RC frames designed according to the previous Chinese codes for seismic design are likely to violate this requirement as the contribution of a cast-in-place floor slab in tension is not included in assessing the moment capacity of the beam in negative bending. This paper proposes three promising beam weakening techniques in combination with FRP strengthening to achieve this strong column/weak beam hierarchy and presents the preliminary results of an ongoing study into the effectiveness of and design procedures for the proposed techniques. Disciplines Engineering | Science and Technology Studies Publication Details Teng, J. G., Zhang, S. S., Jing, D. H., Nie, X. F. & Chen, G. M. (2013). Seismic retrofit of RC frames through beam-end weakening in conjunction with FRP strengthening. In R. Al-mahaidi, S. T. Smith, Y. Bai & X. Zhao (Eds.), Proceedings of the 4th Asia-Pacific Conference on FRP in Structures (APFIS 2013) (pp. 1-8). Victoria, Australia: Swinburne University of Technology. This conference paper is available at Research Online: http://ro.uow.edu.au/eispapers/4957 SEISMIC RETROFIT OF RC FRAMES THROUGH BEAM-END WEAKENING IN CONJUNCTON WITH FRP STRENGTHENING J.G. Teng , S.S. Zhang , D.H. Jing , X.F. Nie 1 and G.M. Chen 3 1 Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, China. 2 School of Civil Engineering, Southeast University, China. School of Civil and Transportation Engineering, Guangdong University of Technology, China. Email: cejgteng@polyu.edu.hk ABSTRACT The strong column/weak beam requirement is now widely accepted in the design of reinforced concrete (RC) frames to achieve good seismic performance. However, many existing RC frames violate this requirement as they were designed according to inadequate design codes (generally previous codes). In particular, RC frames designed according to the previous Chinese codes for seismic design are likely to violate this requirement as the contribution of a cast-in-place floor slab in tension is not included in assessing the moment capacity of the beam in negative bending. This paper proposes three promising beam weakening techniques in combination with FRP strengthening to achieve this strong column/weak beam hierarchy and presents the preliminary results of an ongoing study into the effectiveness of and design procedures for the proposed techniques.The strong column/weak beam requirement is now widely accepted in the design of reinforced concrete (RC) frames to achieve good seismic performance. However, many existing RC frames violate this requirement as they were designed according to inadequate design codes (generally previous codes). In particular, RC frames designed according to the previous Chinese codes for seismic design are likely to violate this requirement as the contribution of a cast-in-place floor slab in tension is not included in assessing the moment capacity of the beam in negative bending. This paper proposes three promising beam weakening techniques in combination with FRP strengthening to achieve this strong column/weak beam hierarchy and presents the preliminary results of an ongoing study into the effectiveness of and design procedures for the proposed techniques.
An investigation of the bituminous coal dissolution phenomena has been undertaken in order to develop information which would be useful in the design and scale-up considerations for a commercial liquefaction plant. The experimental data of this study were derived from pilot plants using various coal liquefaction processes. The data were analyzed in order to better understand the phenomena which occur in the preheater and reactor sections during the liquefaction of coal. Two different stages were found to exist in the coal dissolution reactions. In the initial stage of coal dissolution, a first-order reaction scheme is proposed, whereby coal undergoes a fast thermal reaction producing preasphaltene as the predominant product. Conversion for this reaction is calculated based on the amount of pyridine solubles formed. The rate coefficient for this stage is found to follow an Arrhenius type temperature dependence with an activation energy of 48 approx. 55 Kcal/g-mole. In the second stage of coal dissolution, a slower first-order rate expression is proposed in which the preasphaltene is converted to benzene solubles with subsequent rehydrogenation of the coal-derived solvent. A semi-empirical correlation for the dissolution rate coefficient in the second stage reaction is presented, which reasonably accounts for the effects of temperature, hydrogen partial pressure and of particular importance - reactor hydrodynamics. However, the rate coefficient was found to be practically independent of coal particle size. Finally, the rate of hydrogen absorption during coal dissolution is modeled by assuming that the gas and liquid phases are in equilibrium at the interface. The overall gas absorption coefficient was found to be a function of superficial gas velocity.
