基于本质安全的硝化反应釜的概念设计

Conceptual Design of Stirred Tank Nitration Reactors Based on an Inherently Safer Design Strategy

硝化反应过程广泛应用于国防工业中高性能含能材料的合成,但其具有放热量大,放热速率快,反应易发生失控,硝化产物多易燃易爆的特性,所以硝化反应釜的合理设计非常重要。今将化工过程本质安全设计中的强化、最小化、提高可靠性、限制影响原则应用到硝化反应釜设计中,以降低反应热危险,达到减少危险发生概率,提高反应釜本质安全特性的目标。通过参考常规设计手册并结合硝化反应的特殊性及工程经验,提出了硝化反应釜设计的推荐流程。重点对反应釜中的搅拌系统进行了分析研究,结合流体力学软件FLUENT模拟,通过优化搅拌桨的桨径、组合方式及安装位置来强化釜内流体流动,并对硝化反应釜中常用的四斜叶桨(PBTD45)的径向及轴向影响范围进行了讨论,给出了选择搅拌桨桨径的方法,提出了一些与常规设计经验相比更加细化的设计参数。该研究结果对硝化反应釜的优化设计有较好的参考价值。

Nitration reaction processes are widely used in the synthesis of high performance energetic material in national defense industry. Rational design of stirred tank nitration reactor is crucial due to the strong exothermic, fast heat release rate and easy runaway properties. In addition, products are flammable and explosive. The principles of inherently safer design such as process intensification, minimization, greater reliability, limitation of effects were applied into the design of stirred tank nitration reactors to lower the risk probability and improve the inherent safety of reactors. The general design process was proposed based on conventional design manual together with engineering experience. The mixing system was investigated in detail with FLUENT simulation. Agitator blade diameter, combination mode and installation position were optimized to improve fluid flow in the reactor. The radial and axial fluid velocity distribution were discussed when the agitator PBTD45 was used. The method for agitator diameter selection was proposed, and other more specific design parameters were given compared with conventional design experience.