Abstract

Several methods are applied for soot reduction in industrial flares. However, they usually involve other issues such as flame safety and other pollutant formations; therefore, they should be handled carefully. Splitting flare tip into multiple branches is an idea that is thought to reduce soot formation by increasing the contact surface and providing better mixing. In this study, changing a single tip of an industrial flare into multiple tips was investigated by Computational Fluid Dynamic software Ansys Fluent 18. Reynolds Average Navier–Stokes approach was used to model the fluid flow, and its turbulence was modeled by realizable k–ε model. The steady laminar flamelet model was chosen as the combustion model. Soot formation was modeled using Moss–Brookes approach, and validated by comparing the simulation results with available experimental data. Effects of tip diameter, number of branches, and distance between branches on soot and NO_x yields, and flame stability were studied. According to the results, increasing the number of branches having larger diameters by taking flame stability limitations into consideration, and choosing optimum distances between branches caused significant soot reduction without noticeable changes in the NO_x formation.

Graphic abstract

中文翻译：

---

将单个火炬头分成多个头对减少烟灰的影响

摘要

几种方法可用于减少工业火炬中的烟尘。但是，它们通常涉及其他问题，例如火焰安全性和其他污染物的形成。因此，应谨慎处理。将火炬头分成多个分支的想法被认为可以通过增加接触面积并提供更好的混合来减少烟灰的形成。在这项研究中，改变一个工业火炬成多个尖端的单个尖端通过计算流体动力学软件ANSYS FLUENT 18.雷诺数平均纳维-斯托克斯方法调查了用于流体流动的模式，其湍流通过变现建模ķ - ε模型。选择稳态层流小火焰模型作为燃烧模型。使用Moss-Brookes方法对烟灰的形成进行建模，并通过将模拟结果与可用的实验数据进行比较进行验证。尖端直径，分支的数目，并且在烟灰和NO分支之间的距离的影响_X进行了研究的产率，和火焰稳定性。根据结果​​，通过考虑火焰稳定性的限制来增加具有较大直径的分支的数量，并且选择分支之间的最佳距离导致显着的烟灰减少，而NO _x的形成没有明显变化。

图形摘要