Analysis of the Influence of Chevcon Stacking Patterns on the Occurrence of Self-combustions in Stockpiles 1 & 2 of the UBP PLTUPangkalan Susu, Desa Tanjung Raja Kecamatan Pangkalan Susu, Kabupaten Langkat, Provinsi Sumatera Utara

Abstrak

PT PLN Indonesia Power UBP Pangkalan Susu is located in Tanjung Pasir Village, Pangkalan Susu District, Langkat Regency, North Sumatra Province. PT PLN UBP Pangkalan Susu is a company engaged in the coal-fired power plant industry, which uses coal as its main fuel. The coal used at PT PLN UBP Pangkalan Susu comes from South Sumatra. Due to the large demand for coal-fired power plants, there is a need for large-volume storage facilities. PT PLN UBP Pangkalan Susu has a stockpile with a capacity of 295,000 MT. It uses the FIFO (first in first out) stacking method with a Chevcon (truncated pyramid) stacking pattern. The Chevcon stacking area covers 10,496.9 m2 with a top length of 165 m, a width of 15 m, a bottom length of 198 m, a width of 40 m, a stack height of 10 m, and a stack volume of 34,989.6 m3. The coal pile is checked for temperature regularly every day, at heights of 3 meters, 6 meters, and 9 meters. The average temperature of the Chevcon pile at a height of 3 meters is 41.6˚C, at a height of 6 meters is 44.7˚C, and at a height of 9 meters is 46.9˚C. The average daily temperature is 29.8˚C. The coal pile is routinely checked for temperature, and a significant increase in temperature has been observed from the first day of stacking, with an initial temperature of 34˚C and a maximum temperature of 61˚C. 5. At temperatures ≥ 55˚C, the coal pile shows signs of spontaneous combustion. In the Chevcon stacking pattern, the stack temperature reached 61˚C on the 4th and 8th days. Spontaneous combustion is triggered by the fire triangle, namely heat, air, and fuel. However, it is not only these three elements that can trigger spontaneous combustion, but also the quality of the coal.