【作者】 李伟力；

【导师】 袁竹林；

【作者基本信息】 东南大学 ， 热能工程， 2006， 硕士

【摘要】 煤气化技术是燃煤高效、洁净利用的有效手段。Texaco水煤浆气化技术是目前世界上最先进的煤气化方法之一。水煤浆和氧化剂在气化室内燃烧后产生高温的合成气和熔融态的灰渣,合成气主要成分包括H2、CO和CO2,另外还有少量的H2S等其它气体。从气化室出来的合成气要经激冷室冷却增湿。高温合成气和熔融态灰渣,在激冷室内与水直接接触骤冷,同时发生相变和传热,即熔融态灰渣冷凝固化,高温合成气急剧降温并增湿,过程中气、液、固三相间的热质同时传递规律研究是至关重要的相关环节。从理论上对气液固三相系统中不同相间的热质同时传递进行分析和研究,寻求合理解决和处理不同相间热质传递的方法与途径,建立描述气液固三相系统中存在热质同时传递的数学模型,针对气液固三相系统中热质同时传递相关的科学问题的研究,采用数值实验的方法研究和探索高温、高压条件下气液固三相系统热质同时传递的特征与规律是文的主要研究内容。本文以Texaco气化炉激冷室为研究对象,针对激冷室内部的气、液、固多项复杂流动和传热传质过程建立数学模型,对激冷室中下降管内的流动状况、热量传递和质量传递进行了模拟计算。包括对下降管内壁水膜流动、下降管内部合成气与激冷水之间的热量传递、激冷水受热后相变蒸发以及灰渣颗粒在激冷室内部的流动状况进行模拟研究。模拟结果揭示激冷室内部的热、质传递的一些规律,提出了影响下降管内壁水膜覆盖的因素,影响下降管内部的换热因素以及灰渣的在激冷室内的流动特性。更多还原

【Abstract】 Coal gasification technology is an effective method of coal combustion and usage. Texaco coal slurry gasification technology is one of the most advanced methods of coal gasification field so far. Coal slurry and oxidant combust in the gasification chamber, and this produces compound gas and fused dregs. The main compositions of the compound gas are H2, CO and CO2, in addition a little H2S and other gases. The compound gas coming from the gasification chamber enters into the cooling chamber for cooling and wetting. The high temperature compound gas and fused dregs connect with water directly in cooling chamber, and phase change and heat transfer take place simultaneity, that is to say, the fused dregs condensate and solidify, the heat and mass transfer of gas-liquid-solid three phase in this process is very important. Heat and mass transfer between phase in the three phase system is theoretically investigated, in order to find the reasonable ways to deal with the heat and mass transfer, and to build the model of the system.The cooling chamber of Texaco gasification furnace is taken as the study object in this paper. The mathematical models based on the complex flow and heat and mass transfer process of the inner multiphase flow in the cooling chamber are adopted to study the flow status and heat and mass transfer of vertical pipe, including liquid film flow on the inner wall of the vertical pipe, the heat transfer between the compound gas and cooling water, the evaporation of cooling water after heating, and the flow status of the dreg particles inside the cooling chamber. The simulation results give some relationship curves of the heat and mass transfer inside the cooling chamber, and the author posts the effect factors on flow and heat transfer in the cooling chamber.更多还原