| Syngas (2H2+CO) is produced by partial oxidation of methane, which is an important raw material to produce methanol for Fischer-Tropsch synthesis. In the chemical industry, how to obtain syngas efficiently is research focus. Technology of non-thermal plasma to produce syngas is a meaningful attempt.However, research of the design method for the gliding arc Non-thermal plasma reactor and the scale-up design is an important part of the reactor design. In the chemical industry, the laboratory results is effectively transformed into industrial-scale production process, which is to grasp the rules of scale-up and to utilize techniques and methods of scale-up. The chemical scale-up technique and method include three ways:(1) Experience method. Large amount of experimental work, lack of scientific and high cost;(2) Mathematical simulating method. This method is very suitable process for a thorough understanding.(3) Scale-up method based on the experimental methodology. This method, combining the advantages of other method, is the scientific method of scale-up design.For design the vortex gliding arc non-thermal reactor, the reasonable matching of chemical process parameters has an important influence on the production efficiency of syngas. Based on the partial oxidation of methane of process route, the small test experimental was researched using the vortex gliding arc non-thermal reactor. The physical model of the kind of reactor was supposed to a high speed rotating arc and cylinder shape reactor of homogeneous phase and single chemical reaction process.According to continuous media hypothesis, the number particle motion of non-thermal plasma thermodynamic statistical average was expressed as the physical properties (such as temperature, pressure, viscosity and density, etc.) of micro-element (macro infinitely small) in the chemical reaction.Effect of the matching relationship between single value conditions (O/C ratio, electrode space, gas flow rate and residence time, discharge power) on the reactor performance index (methane conversion, energy efficiency, hydrogen yield and CO yield) were researched.Using the equation analysis and dimensional analysis, the similarity criterias and the quantitative relationships were devised. According to the dimensional analysis, model experimental and numerical experimental, the experimental results of vortex gliding arc reactor were verified and were predicted for the pilot tests results. The major conclusions are as following. On the basis of experimental research and theory analysis, the numerical model of vortex gliding arc reactor for the scale-up design was derived.The experimental platform was built for vortex gliding arc reactor experimental research. On the basis of experimental research, and considering of the promoting effect to methane particle decomposition by gliding arc and dimensional analysis influence to the performance parameter of the reactor, three major dimensionless numbers were got, including Dal number, Varc/Vreactor number and Da number. The relation influencing methane conversion was got by fitting experimental data.According to "Heat string’" model of gliding arc, the gliding arc discharge was simplified to continuous fluid. Interaction between particles of gliding arc was expressed as thermodynamics statistical averages. The numeric calculation model of the vortex gliding arc reaction was established, and the influence to electric arc by flow in reactor was analyzed. Compared with the small test results and calculation results, the error was less than15%. This show that the numerical experiment method not only can provide a strong evidence for the analog modeling, but also predict on the reactor scale-up.In this paper, design techniques and design process of vortex gliding arc reactor can better regulate and give the chemical process parameters of gliding arc reactor design to satisfy essential requirements of engineering scale-up design. However, this design techniques need to be further improved. |
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