CARBON MONOXIDE DILUTION ANALYSIS AT VERTICAL RAISE IN LABORATORY SCALE WITH COMPUTATIONAL FLUID DYNAMICS (CFD) MODELING USING ANSYS SOFTWARE

• Main Author: Yanizar Auliya, Muhammad
• Format: Final Project
• Language: Indonesia
• Subjects: Pertambangan dan operasi berkaitan
• Online Access: https://digilib.itb.ac.id/gdl/view/51456
• Institution: Institut Teknologi Bandung

Underground mining is a mineral and coal mining system where all mining activities are not directly related to outside air. Underground mining systems require blasting which produces toxic and dangerous gases. There was an accident at one of the underground gold mines due to the poisoning of carbon monoxide (CO) gas as a result of blasting in mid-2016. It is necessary to plan a good mine ventilation system by considering the diffusion rate of CO gas which can be described by its diffusion coefficient. In this research, ANSYS software student version with CFD simulation is used to determine the process of CO gas dilution in the vertical raise. Six variations were carried out, namely variations in the distance of the duct to the face and the flow of air flowed through the duct. The initial process is carried out by making geometry, fitting the mesh, and defining the model according to the experiment to get results in the form of contour and CO concentration data against time. There is an effect of air flow on the value of the diffusion coefficient both theoretically (K) and empirically (E), the greater the resulting air flow, the greater the K and E values. Initial estimates state that there is no relationship between thedistance duct- to- face in the range of 1 to 3 times thediameter for raise both K and E values. The difference in K and E values gives a very high error, between 13,071.58% to 84,123.6%. This is because there is a difference in Taylor's experiment with this research, namely in this experiment, the pipe /raise used is vertical and the CO gas is injected for 10 seconds, not completely filled into the raise. In addition, it is also caused by high turbulence factors at the tunnel surface due to changes in the direction of air flow from the air pipe to the tunnel, and high turbulence factors along the tunnel due to the relatively close distance to the work surface, namely (L / D = 20). This is very different from Taylor's theoretical prediction which is intended for fully developed turbulent flow conditions at large L / D (L / D> 500).