Thermodynamical Study on Production of Acetylene from Coal Pyrolysis in Hydrogen Plasma

Abstract

The chemical therm0dynarni.c equilibrium of acetylene production by coal pyrolysis in hydrogen plasma was studied. The thermodynamic equilibrium is obtained by using the method of free energy. Calculated results show that the hydrogen concentration in the equilibrium system is very important for the acetylene production by coal conversion and the energy consumption for the production of acetylene per-kilogram strongly depends on the hydrogen concentration and the temperature.

Production of Acetylene and Acetylene-based Chemicals from Coal

“…Both of these parameters decrease with increasing rank. Qualitatively, coals of high volatile matter but low oxygen content give the best yields of acetylene . Rather, a coal of about 80% carbon and 12% oxygen gives a better acetylene yield .…”

“…Qualitatively, coals of high volatile matter but low oxygen content give the best yields of acetylene. 46 Rather, a coal of about 80% carbon and 12% oxygen gives a better acetylene yield. 45 Other work has suggested 25−44% volatile matter and <9% oxygen [on a dry ash free (daf) basis] as optimum.…”

“…Quenching of the gases leaving the reactor should be nearly instantaneous, ,,, on the order of milliseconds. , Rapid quenching of the product gases is important, ,,,,,, to retard the decomposition of acetylene to the elements or to other hydrocarbons. If allowed to cool slowly, hot acetylene can revert to tar and oil in about 2 s .…”

Numerical Study on the Acetylene Concentration in the Hydrogen-Carbon System in a Hydrogen Plasma Torch

“…This result might be of important guiding significance to the experiment due to the low energy consumption. LITTLEWOOD and WANG Fei [6,15] stated that the yield of acetylene from the coal pyrolysis in a plasma can be enhanced by the abundance of hydrogen due to the higher conversion efficiency of acetylene from coal. But the numerical results presented in this paper (Fig.…”

“…Since the process of producing acetylene from coal pyrogenation in a hydrogenation plasma torch is complicated, it is almost impossible to get the internal physical mechanism underlying the various physical and chemical reactions. For a brief discussion, chemical thermodynamic equilibrium analysis was used to approximatively describe the trend of production generated from chemical reactions [15,16,19] . The chemical thermodynamic equilib-rium with a single phase of the system with a species ratio of C:H:O:Ar=1:13.39:0.073:0.605 was calculated by BITTNER and his co-workers under the considerations of the production components including H, H…”