烧结余热罐式回收系统的基础研究

For the disadvantages of the traditional strand cooler such as the higher rate of air leakage, the lower recovery rate of waste heat, etc, the process of the sinter waste heat recovery with vertical tank was put forward by imitating the structure and process of coke dry quenching and integrating the characteristics of sinter waste heat which is large quantity and medium quality. The feasibility of the recovery system with vertical tank mainly depends on the following 3 fundamental problems, resistance characteristics of the layer, the gas-solid heat transfer characteristics and the effect of cooling velocity for the metallurgical and mechanical properties. Among of them, the scientific evidence or support of the former 2 problems is the theories of flow and heat transfer in fixed beds. Through neglecting the "characteristics" of reaction, mass transfer and etc in the fixed bed of chemical and other fields and integrating the characteristics in vertical tank that the bed of vertical tank is between random close packing and random loose packing ,the geometrical factor is larger, the range of particle size is wider, the shape factor is smaller and etc, the foundation and frontier theory of flow and heat transfer of fixed bed in the chemical field are absorbed and innovated to apply in the bed layer of vertical tank. Based on them, the relations of the 2 three-type variables focusing on the vertical tank and the waste heat recovery system are put forward and researched, and the process parameters of waste heat recovery system are determined. The research aims to make the recovery of vertical tank achieving from idea to theory and causing researchers to support and join the research of this scientific problem, thereby exploring a new way of the more effective recovery and utilization for the sinter waster heat.

针对传统带式冷却机在余热回收利用方面存在着漏风率较高、余热部分回收等先天不足，借鉴干熄焦结构和工艺，结合烧结矿所携带余热数量较大、品质居中的特点，提出罐式回收工艺流程。罐式回收是否可行主要决定于床层阻力特性、气固传热特性以及烧结矿冷却速度对其冶金和机械性能影响3个基本问题，其中，阻力特性和气固传热两个问题的科学支撑是固定床气固流动与传热。将化工等领域中各种固定床层的反应、传质等"特性"去除，结合余热回收罐体内床层介于疏床与密床之间、几何因子较大、颗粒尺寸范围广及形状因子较小等特点，将化工等领域中的有关固定床流动与传热的基础和前沿理论应用于余热回收罐体床层中，借鉴吸收再创新。在此基础上，开展着眼于罐体和整个余热回收系统的2个三类变量关系的研究，藉此确定余热回收系统工艺参数。本项目旨在于实现罐式回收从理念到理论的跨越，引起相关人士的共鸣和支持，从而为烧结余热高效回收与利用探索一条新的途径。

针对传统烧结矿环冷机在余热回收利用方面存在着漏风率较高、余热部分回收等先天不足，借鉴干熄焦结构和工艺，结合烧结矿所携带余热数量较大、品质居中的特点，提出烧结矿余热竖罐式回收工艺流程。竖罐式回收工艺是否可行主要决定于床层阻力特性、气固传热特性以及烧结矿冷却速度对其冶金和机械性能影响3个基本问题。其中，阻力特性和气固传热两个问题的科学支撑是颗粒移动床层气固流动与传热。颗粒移动床与固定床内流动与传热的机理相同，基本规律较为类似。基于此，本项目将化工等领域中各种移动床层、固定床层的反应、传质等"特性"去除，结合余热回收竖罐体内床层介于疏床与密床之间、几何因子较大、颗粒尺寸范围广及形状因子较小等特点，将化工等领域中的有关移动床、固定床流动与传热的基础和前沿理论应用于余热回收罐体床层中，借鉴吸收再创新。在此基础上，开展着眼于罐体和整个余热回收系统的两个三类变量关系的研究，藉此确定余热回收系统工艺参数。.主要研究结果如下：.（1）影响罐式气固阻力特性的主要因素是：颗粒表观流速、料层高度、颗粒当量直径、颗粒温度及边缘效应等。料层表观流速、颗粒当量直径对料层阻力的影响较大。.（2）影响烧结矿移动床层气固传热的主要因素有：颗粒表观流速、料层高度、颗粒当量直径等。随着烧结矿颗粒粒径的减小、冷却空气流量的增大、冷却段高度的增加、烧结矿质量流量的增大，气固传热过程增强，其中，烧结矿颗粒粒径、冷却空气流量对气固传热的影响较大，冷却段高度、烧结矿质量流量影响较小。.本项目提出了一条变革性工艺路线，实现了烧结矿竖罐式回收从理念到理论的跨越，为烧结矿余热高效回收与利用探索一条新的途径，进而为后续的技术攻关奠定理论基础。