Numerical study of a packed-bed microreactor based on Sierpinski fractal principle

Abstract

In this paper, a packed-bed microreactor based on Sierpinski fractal principle is studied. Several factors that may affect the catalytic reaction are discussed, including the inlet of primary fractal and quadratic fractal, the pressure drop, the size of catalyst pellets, the porosity of pellet, the porosity of bed and concentration ratio of reactants at inlet of microreactor. Some important conclusions are obtained. Firstly, the change of pressure drop has a significant effect on the reaction results. The increase in pressure drop leads to the low conversion rate of reactants and the formation of products in the reaction. Secondly, the inlet of primary fractal and quadratic fractal has little effect on the reaction results, but has an effect on the reaction process. Then, the radius and porosity of single pellet have little effect on the reaction results. When the porosity of the bed is changed, the reaction results are obviously affected. Finally, changing the concentration ratio leads to an increase in the concentration of the products, but the selectivity and yield of the products decrease. This study has guiding significance for the selection of parameters of packed-bed microreactor.

NO reduction mechanism in microreactor with cantor fractal structure

“…With the rapid development of fossil energy and industries including manufacturing and transportation, Earth's atmosphere is harbouring large amount of polluting gases and particles, and the environment is gradually deteriorating, causing huge threats to human health 1‐4 . According to the ‘Annual Report on Environmental Management of Motor Vehicles’ in China, the total annual emission of particulate matter (PM) from motor vehicles is ≈442 000 t; 90% of PM generated under poor operating conditions includes <1‐um (PM1) sized particles of soot, heavy metal oxides and lead oxide 5‐8 . Therefore, it is particularly necessary to separate PM, especially PM1, from the airflow.…”

“…[1][2][3][4] According to the 'Annual Report on Environmental Management of Motor Vehicles' in China, the total annual emission of particulate matter (PM) from motor vehicles is ≈442 000 t; 90% of PM generated under poor operating conditions includes <1-um (PM1) sized particles of soot, heavy metal oxides and lead oxide. [5][6][7][8] Therefore, it is particularly necessary to separate PM, especially PM1, from the airflow. In addition to PM, the combustion of fuel in automobile exhaust devices generates several harmful gases causing environmental pollution.…”