A Study on the Ignition Temperature and Ignition Induction Time According to Storage Amount of Wood Pellets

Hyeong-Seok, Kim; Yu-Jung, Choi; Jung-Hun, Kim; Phil-Hoon, Jeong; Jae-Woo, Choi

doi:2019.33.1.7

Fire Sci. Eng. > Volume 33(1); 2019 > Article

Fire Science and Engineering 2019;33(1):7-14.
DOI: https://doi.org/10.7731/KIFSE.2019.33.1.007 Published online February 28, 2019.

우드펠릿의 저장량에 따른 발화온도 및 발화유도시간에 관한 연구

김형석, 최유정, 김정훈, 정필훈, 최재욱

¹부경대학교 대학원
²부경대학교 대학원
³광명토탈엔지니어링
⁴부산 경상대학교 소방안전.전기전자계열
⁵부경대학교 소방공학과

A Study on the Ignition Temperature and Ignition Induction Time According to Storage Amount of Wood Pellets

Kim Hyeong-Seok, Choi Yu-Jung, Kim Jung-Hun, Jeong Phil-Hoon, Choi Jae-Woo

¹Pukyong National Univ.
²Pukyong National Univ.
³Kwangmyung Total Engineering
⁴Division of Fire Protection & Safety Engineering, Electrical & Electronics Engineering, Busan Kyungsang College
⁵Dept. of Fire Protection Engineering, Pukyong National Univ.

요약

우드펠릿은 화력발전소 및 화목 보일러의 연료로 많이 사용되고 있으나 발열량이 높은 우드펠릿을 장기간 보관 시 자연발화의 위험성이 있다. 본 연구에서는 시료 용기의 크기에 따라 유량의 변화에 따른 최소자연발화온도와 발화한계온도를 구하였으며, 발화한계온도를 이용하여 겉보기 활성화 에너지를 측정함으로써 우드펠릿의 발화 특성을 예측하였다. 겉보기 활성화 에너지는 190.224 kJ/mol을 구하였다. 용기에 저장된 시료량이 두꺼워질수록 시료 표면에서 중심까지의 열전달이 어려워 발화유도시간이 긴 것으로 나타났으며, 용기의 크기가 같을 경우 유량의 양이 많아 질수록 자연발화온도는 낮아졌다. 또한 시료용기가 커질수록 자연발화온도는 낮아지고 발화유도시간은 길어지는 것으로 나타났다.

Abstract

While wood pellets are often used as a fuel in thermoelectric power plants and firewood boilers, there is a risk of ignition temperature when strong wood pellets, which have a high calorific value, for prolonged periods of time. In this research study, the minimum auto ignition temperature and the ignition limitation temperature according to the change in flow rate depending on the size of the test vessel were calculated, and based on these temperatures, the apparent activation energy was calculated to predict the combustive properties of the material. The apparent activation energy was calculated to be 190.224 kJ/mol. The thicker the sample is storage in the vessel, the longer the ignition induction time was due to the increased difficulty in heat being transferred from the surface of the vessel to the middle section area of the vessel. For vessel of the same size, the higher the flow rate, the lower the auto ignition temperature was. It was also confirmed that increases in the size of the test vessel lowered the auto ignition temperature and increased the ignition induction time.

Key Words: Flow rate, Minimum ignition temperature, Apparent activation energy, Ignition induction time