DESIGN MODIFICATION OF 4000 TPH CAPACITY COAL STOCKPILE TRANSFER TOWER

• Main Author: Kamil Rota Pranata, Insan
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/85022
• Institution: Institut Teknologi Bandung

In one of the largest Indonesian coal mining companies, a stockpile transfer tower (STT) is used to proportionately divert the coal coming from the overland conveyor 2 (OLC-2) to either stacking or reclaiming conveyor at the coal terminal (CT). The STT consists of 12 major parts. Two of which, Transition Chute 2 and Bottom Chute Stacker, were observed to experience excessive wear. Finding out the cause of this wear was vital, but neither direct observation nor run test was possible due to the confined spaces. Therefore, numerical modeling and analyses were preferred to address this issue. This study developed and validated an accurate and computationally feasible Discrete Element Method (DEM) model using the Angle of Repose Test and Trajectory Validation – with an error of 0.5% & 4.92%, respectively. Wear and chute blockage analyses were performed to obtain the rate of thickness loss at 4000 TPH and chute flow performance at 4500 TPH. Rates of thickness loss at Transition Chute 2 and Bottom Chute Stacker were calculated to be 55.79 and 4.95 mm/year, respectively. This severe wear was due to coal streams abrading the surfaces at high velocities, up to 14 m/s. No potential for blockage was identified. Next, Design Requirements and Objectives (DR&O) were determined, and four modified design alternatives were developed and later evaluated. Design 4, that is, the design with embedded 1 m vertically interspaced, 50 mm wide, 6 mm thick Zirconia- Toughened Alumina (ZTA) ledges in the Transition Chute 2 and Bottom Chute Stacker, successfully reduces the rate of thickness loss to below 1.63 mm/year without any chute blockage issue. Despite the high material cost, the proposed design modification significantly minimized production loss and ultimately scored 8.1 points, which is the highest in the weighted decision matrix, making it the most optimum design modification.