双碳战略目标下,煤气化技术将会是我国未来煤炭领域的重要发展路线。在煤气化技术推广应用中,熔渣的流动行为严重影响气化炉的平稳运行时长,间接影响合成气的质量和炉壁的热量损失,有效求解流动参数的熔渣流动特性预测模型备受关注。本研究论述了现有的气化炉内熔渣流动特性的预测模型,并展望了预测模型的未来研究方向。综述当下,预测模型根据熔渣流动维数可分为一维预测模型和二维预测模型;一维稳态和非稳态预测模型均经历了构建和完善阶段;二维预测模型因无相关的数学公式描述和流动理念假设尚处于构建阶段;通过对液态熔渣的温度分布、附加应力的取舍,临界黏度的选取和熔渣黏度的处理方式等方面可以提高模型的计算精度。展望未来,一维预测模型的应用场景需更完善的规定,针对稳态和非稳态预测模型求解的参数需要更细致的辨析;二维预测模型的构建理论需更详细的突破,明确非稳态工况下熔渣在轴向和周向上流动的优先级;流动预测模型的计算精度需更全面的提升,熔渣性质的非恒定性、熔化的不均匀性、烟气流速的波动性等因素需要侧重考虑。

Under the " dual carbon" strategic goal, coal gasification technology will be an important development path in China′s futurecoal industry. In the promotion and application of coal gasification technology, the flow behavior of slag seriously affects the stable operation time of gasifiers, indirectly affecting the quality of synthesis gas and the heat loss of furnace walls. The effective prediction model forslag flow characteristics to solve flow parameters has attracted much attention. This study discussed the existing predictive models for theflow characteristics of slag in gasifiers and looks forward to the future research directions of predictive models. At present, prediction models can be divided into one-dimensional prediction models and two-dimensional prediction models based on the dimension of slag flow.Both one-dimensional steady-state and non-stationary prediction models have gone through the stages of construction and improvement.The two-dimensional prediction model is still in the construction stage due to the lack of relevant mathematical formula descriptions andflow concept assumptions. The calculation accuracy of the model can be improved by considering the temperature distribution of liquidslag, the selection of additional stress, the selection of critical viscosity, and the treatment of slag viscosity. Looking ahead to the future,the application scenarios of one-dimensional prediction models require more comprehensive regulations and more detailed analysis is needed for the parameters solved by steady-state and non-stationary prediction models. The construction theory of two-dimensional predictionmodels requires a more detailed breakthrough, clarifying the priority of slag flow in the axial and circumferential directions under nonsteadystate conditions. The calculation accuracy of slag flow prediction models needs to be comprehensively improved, with a focus on factorssuch as the non-constancy of slag properties, non-uniformity of melting, fluctuation of flue gas flow rate, and diversity of coal ash types.

0 引言

1 熔渣流动预测模型的分类

   1.1 一维预测模型

   1.2 二维预测模型

2 熔渣流动预测模型的构建

   2.1 一维稳态预测模型

   2.2 一维瞬态预测模型

   2.3 二维模拟预测模型

3 熔渣流动预测模型的完善

   3.1 一维稳态预测模型

   3.2 一维瞬态预测模型

4 一维预测模型的计算精度

   4.1 熔渣温度的分布

   4.2 附加应力的取舍

   4.3 临界黏度的选取

   4.4 熔渣黏度的处理

5 结语与展望