Advanced Materials Research Vol. 742

Abstract: A practical calculation method to determine the vacuum degree of a mechanical cleaning system is proposed mainly based on the theories of fluid mechanics. The system for cleaning of product oil tanks is operated relying on vacuum suction and simplified without heating section comparing with the system for crude oil tanks. It shows that the determination of vacuum level depends on two factors: to overcome the frictional resistance of suction tank's inlet pipes and to meet the net positive suction head (NPSH) required for a centrifugal pump fixed on outlet pipes of a suction tank. So, the higher and lower limits of vacuum degree can be found. The calculating method of vacuum degree is proved in a real system.

Abstract: The absorption separation method is often applied to recover the gasoline vapor. Several absorbents with good performance, such as dioctyl phthalate, dinonyl phthalate, squalane and AbsFOV-II, were selected to absorb the gasoline vapor from the vapor-air mixture. Based on the simulation software Aspen Plus, the absorption effect of the absorbents on the vapor was evaluated, and some key factors such as the plate number of the absorption tower, the temperature of the absorbents, and the liquid-gas ratio were considered and simulated for the gasoline vapor absorption. The simulation results showed that AbsFOV-II was the most effective absorbent, and the optimized process conditions for the gasoline vapor absorption were as follows: the tower plate number, the absorbent temperature and the liquid-gas ratio were 10, 15 °C and 70 L/m³, respectively, and then the absorption efficiency can be access to 97.5%. The simulation results can provide some guidance for the improvement and optimization of the vapor absorption process.

Abstract: Based on actual measurement data in Da Ping as the samples,according to the experience, and ends with calculate every factors weight and height prediction of the water conducted zone by Matlab using the combination entropy-weight method and analytic hierarchy process. this paper introduces a comprehensive prediction model consisting of analytic hierarchy process and combination entropy-weight method. The method,overcoming weights imbalance,gives the evaluation result better than does the single analytic hierarchy process, it is a new valid method for scientific forecast on water conducted zone.

Abstract: The comparative study of numerical results on pulverized coal combustion process with CFD has become an important measure for direct engineering practice. In this paper, a combustion facility was simulated numerically with the Fluent code to investigate the process of coal combustion. Firstly, geometric models, grid and boundary type were established in the Gambit. Secondly, required models, physical properties and working conditions were chosen in the solver. Then, the important diagrams of each component displayed distinctly in the post professor. The simulation results showed that the rules of the volatile releasing and combustion processes of coke could provide important references to improve the combustion of the pulverized coal.