Gasification kinetic parameters of coal char based on the random pore (RPM) model are obtained with CO2 and H2O using a high-pressure thermogravimetry analysis (TGA) under atmospheric pressure and 4.0 MPa pressure, considering the influence of internal diffusion and particle structure varying with carbon conversion. The Chemical Percolation Devolatilization (CPD) model is used to modify the actual volatile content. Through the coupling of the gasification kinetic reaction model, a comprehensive numerical simulation method of the entrained flow gasification process is established. This method is used to simulate the typical gasifier of HTL (a gasification technology of Changzheng Engineering Co.) in an industrial plant. The research shows that the intrinsic reaction parameters obtained by TGA under high pressure can give a more reasonable reaction state of coal char particles in the gasifier than that measured under atmospheric pressure, and the simulation results are in good agreement with the industrial data. In addition, HTL adopts a single top-fired burner and multi-channel swirling feed type. The particles are entrained and mixed with swirling oxygen, and the combustion reaction is completed quickly in the upper part of the gasifier. In contrast, the gasification reactions are relatively slow and mostly dominate in the recirculation zone and pipe flow zone, leading to high carbon conversion.

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Safety Management Performance of Air Traffic Control is affected by many factors. Via questionnaire statistics analysis and Exploratory Factor Analysis (EFA) to optimize items and extract factors, the authors confirm five main effective factors at last, including work initiative, communication and exchange, team cohesion, system completeness and leadership management, and all of them have passed the reliability test and validity test so as to enhance the level of safety management of Air Traffic Control.

The research object in this paper is an industrial HTL gasifier in a plant. A three-dimensional model is built. The chemical percolation devolatilization (CPD) model is used to calculate the pyrolysis reaction. Considering the gas diffusion in the inner pores of the particle and the evolution of pore structure, the random pore model (RPM) was used to simulate the chemical reaction on the particle surface, and the gasification reaction kinetic parameter of char was measured by high-pressure thermogravimetry analysis. The slag model was constructed to describe the formation process and distribution of slag. Through the coupling of the above models, a simulation method that combines several submodels for the entrained flow gasifier is built, and the results from simulation are in good agreement with the industrial data. Furthermore, the effect of the uniformity of pulverized coal injection was analyzed by this method. The simulation results reflect that the asymmetric feed of coal will affect gas-solid mixing and reduce carbon conversion, and it leads to a higher local wall temperature and a lower ratio of crude slag to fine slag.