论文总字数：24054字

摘 要

高炉渣作为生铁冶炼的主要副产品，其具有高品质废热的特性使其具有很高的回收意义。目前高炉渣的处理主要采用湿法工艺，即使用水淬法将高热量的熔渣快速冷却，其形成的物质可以作为水泥工业的主要原料二次利用。但湿法工艺缺点也很大，不仅新水消耗量大，浪费丰富的余热资源，而且会排放有害气体造成严重的环境污染。高炉渣干法离心粒化因其自身特点，可以避免及克服水淬工艺的缺陷，也可以继承其优点，作为水泥原料，是当前业界研究的热点。离心粒化法，尤其转盘离心粒化，因为其能耗低、设备结构简单、可以和各种余热回收设备配合使用，是目前最有开发潜能的干式粒化方法之一。本文通过建立空气-熔渣相界面的数学模型，模拟计算了熔渣在空气相界面的演化过程。从微观的角度分析转盘边缘液膜的破碎与断裂行为，本文主要工作及结论如下：

首先，本文阐述了研究课题的由来，综述了国内国外离心粒化的发展现状，并根据研究课题建立了熔渣转盘离心粒化的数值模型。本文以Fluent软件耦合VOF方法为基础，模拟了熔渣在转盘上粒化过程。探究了液膜情况；分析了液柱的形成与发展，探索了液柱数量和液柱长度；从微观的角度分析转盘边缘液膜的破碎与断裂行为；最后根据所得模拟结果计算尖端直径，界面波波长以及平均液滴直径；所得结果如下：

当熔渣落到高速旋转的转盘中心后，随转盘沿切向以及径向向外运动。当转盘表面完全润湿时，熔渣将在转盘表面形成连续分布的具有自由表面的膜状流。液膜运动至转盘边缘后失稳破碎，并最终断裂成为熔渣液滴。得出液膜在转盘边缘处的厚度为0.9mm。得到总根数为82根，而液柱长度L为3.22mm和平均尖端直径1.558mm。并发现，粒化进入准稳态后，液柱长度保持不变。本次模拟中所得出的界面波波长λ_d为1.809mm，主导的断裂模式形式是短波形式。在粒化进入准稳态阶段后，所测得的平均粒径为1.707mm。

关键词：熔渣；离心粒化；数值模拟

ABSTRACT

As a main by-product of pig iron smelting, blast furnace slag has the characteristics of high-quality waste heat, making it highly recyclable. At present, the treatment of blast furnace slag mainly adopts the wet process. Even if the high-heat slag is rapidly cooled by the water quenching method, the formed material can be used as the main raw material of the cement industry for secondary use. However, the disadvantages of the wet process are also great. Not only does the new water consume a large amount, it wastes a lot of waste heat resources, and it emits harmful gases that cause serious environmental pollution. Due to its own characteristics, blast furnace slag dry granulation can avoid and overcome the defects of the water quenching process, and it can also inherit its advantages. As a raw material for cement, it is currently a hot research topic in the industry. Centrifugal granulation, especially rotary granulation, is one of the most promising methods for dry granulation because of its low energy consumption, simple equipment structure, and its ability to be used with a variety of waste heat recovery equipment. This paper establishes the mathematical model of the air-slag phase interface and simulates the evolution process of slag in the air phase interface. From the microscopic point of view, the fracturing and fracturing behavior of the liquid film at the edge of the turntable is analyzed. Performed the following work：

Firstly, this paper expounds the origin of the research topic, summarizes the development status of centrifugal granulation at home and abroad, and establishes a numerical model of the slag rotating disk centrifugal granulation according to the research topic. Based on the Fluent software coupled VOF method, this paper simulates the granulation process of slag on the turntable. The conditions of the liquid film were investigated. The formation and development of the liquid column was analyzed. The number of liquid columns and the length of the liquid column were explored. The fracture and fracturing behavior of the liquid film at the edge of the turntable was analyzed from the microscopic point of view. Finally, the tip diameter was calculated based on the simulation results. The wavelength of the wave and the average droplet diameter; the result is as follows: When the slag falls on the center of the rotating disk at a high speed, the turret moves along the tangential direction and radially outward. When the surface of the turntable is completely wet, the slag will form a continuously distributed film-like flow with a free surface on the surface of the turntable. After the liquid film moves to the edge of the turntable, it breaks down and breaks down, and finally breaks into slag droplets. The thickness of the liquid film at the edge of the turntable is 0.9 mm. The total number of roots obtained was 82, and the length L of the liquid column was 3.22 mm and the average tip diameter was 1.558 mm. It was found that the length of the liquid column remained unchanged after granulation entered the quasi-steady state. The wavelength of the interfacial wave λd obtained in this simulation is 1.809 mm, and the dominant fracture mode is in the form of short wave. After granulation entered the quasi-steady state stage, the measured average particle size was 1.707 mm.

Key words: slag; centrifugal granulation; numerical simulation

目录

摘要 I

ABSTRACT II

第一章 绪论 1

1.1 研究背景 1

1.2 干法工艺发展现状 2

1.2.1 离心粒化法发展 5

1.2.2 国外部分 6

1.2.3 国内部分 6

1.3 文章内容 7

第二章 数值模型 9

2.1 引言 9

2.2 控制方程 9

2.3 模型建立 10

2.3.1 假设条件 10

2.3.2 物性参数 10

2.3.3 计算模型 11

2.3.4 界面捕捉方案 11

2.4 网格划分 13

2.4.1 网格独立性验证 14

2.5 Fluent 设置 15

2.5.1 基本设置 15

2.5.2 Solution（求解设置） 16

2.5.3 初始化设置 16

2.5.4 计算 16

2.6 小结 17

第三章 模拟结果 18

3.1 引言 18

3.2 空气-熔渣相界面演化过程 18

3.3 液膜分析 21

3.4 液柱形成与发展 21

3.4.1 液柱数量 22

3.4.2 液柱长度和尖端直径 23

3.5 液柱断裂原理 24

3.5.1 液滴形成机制 24

3.5.2 界面波波长 25

3.5.3 液滴直径 25

3.6 经济性分析 26

第四章 总结与展望 28

4.1 总结 28

4.2 展望 28

参考文献 30

致谢 33

第一章 绪论

1.1 研究背景

当前社会大量使用化石燃料已经对自然环境造成了严重危害，并且伴随着能源枯竭，越来越多人们把目光投向有效提高能源的综合利用率上而不是新能源的开发利用。钢铁工业的能耗非常巨大，约占中国总能耗的15%左右^[1]。而钢铁工业的主要废料就为高炉炉渣，每生产500kg铁约会生成150kg高炉炉渣，其出炉温度非常高，一般在1450℃-1550℃，含有大量热能，约占整个钢铁厂高温余热总量的28%。2014年我国生铁产量约7.09亿吨，副产高炉渣约2.1亿吨，按照每吨渣约含有1.83×10⁶kJ的余热（从1500˚C冷却至25˚C）计算，高炉熔渣所废弃的热量达到了3.843×10⁸GJ热量。如果这一部分余热能够被高效地回收，那么若折合成标准煤，我们每年大约可以节省1300万吨，减排2000万吨CO₂以及减少大量SO₂、H₂S等大气污染物的排放，这对钢铁工业节能减排，提高能源综合利用率至关重要^[2]。而离心粒化法，尤其转盘离心粒化，是目前最具潜力的干式粒化方法之一，其动力消耗低、设备简单紧凑、易于与各种余热回收设备配合使用，具有广阔的应用前景。

请支付后下载全文，论文总字数：24054字