ANALISIS SIMULASI VENTILASI TAMBANG BATUBARA BAWAH TANAH PT ABC DENGAN METODE LONGWALL MENGGUNA

• Main Author: Qodir Ibrahim J, Muhammad
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/56466
• Institution: Institut Teknologi Bandung

Underground mining requires safe and comfortable air conditions to ensure mining activities can run effectively. Sufficient supply of fresh air to dilute harmful dust and gases. In longwall mines that have high levels of methane emissions, a supply of air is required at the heading face to dilute the methane produced from the gob. The required air requirements are based on workers, methane gas, resistance, and pressure loss. The maximum air requirement is added to 19% of the total air requirement and the threshold concentration value for methane gas is based on the Kepdirjen Minerba 185.K/37.04/DJB/2019 and Kepmen ESDM No.1827 K/30/MEM/2018. The total air requirement obtained from the calculation is used as a consideration in modeling air ventilation on Ventsim Visual 5 and simulations are carried out using fans and ducts to meet the required air requirements. Based on the parameters obtained from the company where PT ABC conducts longwall mining on seam F with a coal thickness of 5.3 m, a coal seam slope of 9-18°, and is in the final stages of mining. The parameters obtained affect the final design on Ventsim Visual 5. The ventilation system used in PT ABC's underground coal longwall mine is an exhaust system using a 250 kW main fan with a total of 1 unit and 1 reserve (working with a pressure of 2,512 Pa at a discharge of 135 m3/s). As for local ventilation with a forcing system using a 60 kW local fan with a total of 3 units and 3 reserves (working with a pressure of 1.517 Pa at a flow rate of 19 m3/s). Local ventilation is channeled through air pipes with a diameter of 1.2 m with a length of 1,230 m to 2,222 m. Coal production needs to be reduced for location M and N so that methane gas can be controlled and the minimum air velocity for the heading face is increased from 0.13 m/s to 1 m/s. The discharge obtained after adjustment for the mining face is 59 m3/s and for the heading face 15 m3/s. Total debit in year 1 is 158 m3/s, year 2 is adalah 137 m3/s, year 3 is adalah 136 m3/s, year 4 is 135 m3/s, and year 1 is 137 m3/s. The effective temperature in mining face between 21.5-22.4 °C, on the heading face ranges from 22-24.4 ° C. Relative humidity ranges from 72-80%. The largest cost of ventilation is used to meet electricity needs with a proportion of 88% of the total cost of ventilation. Operating costs for ventilation in year 1 is Rp 5,957,781,394, year 2 is Rp 5,860,502,213, year 3 is Rp 6,297,607,059, year 4 is Rp 5,971,386,482, and year 5 is Rp 4,993,730,501.