Yan Hongjie

Kinetic model on coke oven gas with steam reforming

The effects of factors such as the molar ratio of H2O to CH4 (n(H2O)/n(CH4)), methane conversion temperature and time on methane conversion rate were investigated to build kinetic model for reforming of coke-oven gas with steam. The results of experiments show that the optimal conditions for methane conversion are that the molar ratio of H2O to CH4 varies from 1.1 to 1.3 and the conversion temperature varies from 1 223 to 1 273 K. The methane conversion rate is more than 95% when the molar ratio of H2O to CH4 is 1.2, the conversion temperature is above 1 223 K and the conversion time is longer than 0.75 s. Kinetic model of methane conversion was proposed. All results demonstrate that the calculated values by the kinetic model accord with the experimental data well, and the error is less than 1.5%.

Analysis on Energy Consumption for Alumina Production Basing on Exergy Intensity-Energy Intensity-Product Ratio Analysis Model

Energy consumption has taken more and more attention in process industries to enhance their competitiveness in the world. An effective analysis method will be very helpful to provide the direction of energy saving for a plant. Exergy analysis method was introduced into energy intensity-product ratio analysis model (e-p analysis model), and exergy intensity-energy intensity-product ratio analysis model (d-e-p analysis model) was developed in this paper. Energy consumption of an alumina plant which adopts the combined Bayer and sinter method was calculated as a case study based on the d-e-p analysis model. The result shows that slurry sintering (SS), tube digestion (TD), aluminium trihydrate calcining (TC) and evaporation (EP) have the highest comprehensive exergy intensity in the nine unit processes, and the level of its energy utilization is influenced by the energy efficiency and product ratio in the plant. Energy saving brought out by technical innovation in unit process is perhaps covered because of the increasing of product ratio. Exergy loss and the distribution of exergy loss in the alumina plant were studied and the direction of energy saving can be found from the results.