Purpose

The dryer feed chute of the pellet plant plays an important role in the pelletizing process. The chute discharges sticky and moist iron ore fines (<1 mm) to the inline rotary dryer for further processing. Since the inception of the installation of the dryer feed chute, the poor flowability of the feed materials has caused severe problems such as blockages and excessive wear of chute liners. This leads to high maintenance costs and reduced lifetime of the liner materials. Constant housekeeping is needed for maintaining the chute and reliable operation. The purpose of this study is to redesign the dryer feed chute to overcome the above challenges.

Design/methodology/approach

The discrete element method (DEM) has been used to model the flow of cohesive materials through the transfer chute. Physical experiments have been performed to understand the most severe flow conditions. A DEM material model is also developed for replicating the worst-case material condition. After identifying the key problem areas, concept designs were proposed and simulated to assess the design improvements to increase the reliability of chute operation.

Findings

Flow simulations correlated well with the existing flow behavior of the iron ore fines inside the chute. The location of the problematic areas has been validated with that of the previously installed chute. Subsequently, design modifications have been proposed. This includes modification of deflector plate and change in slope and cross-section of the chute. DEM simulations and analysis were conducted after incorporating these design changes. A comparison in the average velocity of particle and force on chute wall shows a significant improvement using the proposed design.

Originality/value

Method to calibrate DEM material model was found to provide accurate prediction and modeling of the flow behavior of bulk material through the real transfer chute. DEM provided greater insight into the performance of the chute especially modeling cohesive materials. DEM is a valuable design tool to assist chute designers troubleshoot and verify chute designs. DEM provides a greater ability to model and assess chute wear. This technique can help in achieving a scientific understanding of the flow properties of bulk solids through transfer chute, hence eliminate challenges, ensuring reliable, uninterrupted and profitable plant operation. This paper strongly advocates the use of calibrated DEM methodology in designing bulk material handling equipment.

中文翻译：

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铁矿石承载转运槽的离散元法设计改进

目的

制粒厂的干燥机进料槽在制粒过程中起着重要作用。溜槽将粘性和潮湿的铁矿石细粉 (<1 毫米) 排放到在线旋转干燥机中进行进一步加工。干燥机自安装进料溜槽以来，给料流动性差，造成溜槽内衬堵塞、过度磨损等严重问题。这导致高维护成本和内衬材料的寿命缩短。需要持续的内务管理以维持斜槽和可靠的运行。本研究的目的是重新设计干燥机进料槽以克服上述挑战。

设计/方法/方法

离散元方法 (DEM) 已用于模拟粘性材料通过转移槽的流动。已进行物理实验以了解最严酷的流动条件。还开发了 DEM 材料模型以复制最坏情况的材料条件。在确定关键问题区域后，提出并模拟概念设计，以评估设计改进，以提高溜槽运行的可靠性。

发现

流动模拟与溜槽内铁矿石细粉的现有流动行为密切相关。问题区域的位置已经与之前安装的滑槽的位置进行了验证。随后，提出了设计修改。这包括修改导流板以及改变斜槽的斜率和横截面。在纳入这些设计更改后，进行了 DEM 模拟和分析。粒子的平均速度和斜槽壁上的力的比较表明，使用所提出的设计有显着的改进。

原创性/价值

发现校准 DEM 材料模型的方法可以提供通过真实转移槽的散装材料流动行为的准确预测和建模。DEM 提供了对斜槽性能的更深入了解，尤其是对粘性材料进行建模。DEM 是一种有价值的设计工具，可帮助斜槽设计人员排除故障并验证斜槽设计。DEM 提供了更强大的建模和评估斜槽磨损的能力。该技术有助于科学地了解通过转移槽的散装固体的流动特性，从而消除挑战，确保可靠、不间断和有利可图的工厂运营。本文强烈主张在设计散装物料处理设备时使用校准的 DEM 方法。