| A high-heating-rate device, i.e. wire-mesh reactor, has been developed in this research project. The detailed design and modifications of this apparatus have been described in this thesis. The reactor structure, temperature measurement, heating rate control system, as well as gas lining under different reaction conditions have been presented. The process of the development of this wire-mesh reactor has also been described with all the difficulties encountered being listed. The advantages of the reactor and the places where need to be further improved have been discussed in this thesis. Some carefully designed tests have been carried out on this reactor to verify its reproducibility and reliability. These tests mainly focused on the elements and char structures. Elemental analysis and combustion reactivity on TGA have been completed for these purposes. The data suggest that the experiment results on the wire-mesh apparatus are reliable and comparable to the results from other reactors.By using this system, the pyrolytic properties of Shenhua coal has been studied with the heating rates at 20K/s and 1000K/s, and the holding temperature up to 950°C. The samples obtained from the experiments were analyzed by BET to determine the specific surface area and pore structures. The SO2 adsorption capability of char was investigated by TGA under 80°C against a gas mixture containing 0.9% vol. SO2 at a flow rate of 110ml/min. Four kinds of chars prepared under 3 different pyrolysis temperatures and 2 different heating rates have been investigated. The results of char combustion have been compared with the findings from other researchers. It is obvious that, chars prepared under higher heating rate (1000K/s) have larger average pore diameter than those from lower heating rate (20K/s), although they possess less specific surface area and pore volume. The chars from higher heating rate appear to be more reactive in SO2 adsorptsion and combustion.
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