폐타이어 분쇄물의 자연발화현상에 대한 재연실험 및 열분석에 관한 연구 = A Study on Replay Experiments and Thermal Analysis for Autoignition Phenomenon of Shredded Waste Tires

다국어 초록 (Multilingual Abstract)

These days, spontaneous ignition phenomena by oxidizing heat frequently occur in the circumstances of processing and storing waste tires. Therefore, to examine the phenomena, in this work, this researcher conducted the tests of fires of fragmented waste tires (shredded tire), closely investigated components of the fire residual materials collected in the processing and storing place, and analyzed the temperature of the starting of the ignition, weight loss, and heat of reaction. For the study, this researcher conducted fire tests with fragmented waste tires in the range of 2.5 mm to 15 mm, whose heat could be easily accumulated, and performed heat analysis through DSC and TGA, DTA, DTG, and GC/MS to give scientific probability to the possibility of spontaneous ignition. According to the tests, at the 48-hour storage, rapid increase in temperature (178℃), Graphite phenomenon, smoking were observed. And the result from the DTA and DTG analysis showed that at 166.15℃, the minimum weight loss occurred. And, the result from the test on the waste tire analysis material 1 (Unburnt) through DSC and TGA analysis revealed that at 180℃ or so, thermal decomposition started. As a result,the starting temperature of ignition was considered to be 160℃ to 180℃. And, at 305℃, 10 % of the initial weight of the material reduced, and at 416.12℃, 50 % of the intial weight of the material decreased. The result from the test on oxidation and self-reaction through GC/MS and DSC analysis presented that oxidized components like 1,3 cyclopentnadiene were detected a lot. But according to the result from the heat analysis test on standard materials and fragmented waste tires, their heat value was lower than the basis value so that self-reaction was not found. Therefore, to prevent spontaneous ignition by oxidizing heat of waste tires, it is necessary to convert the conventional process into Cryogenic Process that has no or few heat accumulation at the time of fragmentation. And the current storing method in which broken and fragmented materials are stored into large burlap bags (500 kg) should be changed to the method in which they are stored into small burlap bags in order to prevent heat accumulation.

국문 초록 (Abstract)

본 연구에서는 최근 빈번히 발생하고 있는 폐타이어의 가공 및 저장상황에서의 산화열에 의한 자연발화현상을 규명하기 위해 폐타이어 분쇄물에 대한 화재 재연실험과 가공 및 저장장소에서 수거한 화재 잔존물에 대한 면밀한 성분 분석및 발화개시온도, 무게감량, 반응열 등을 분석하였다. 이를 위해 열축적이 용이한 폐타이어 분쇄물 2.5~15 mm 범위의파쇄된 분쇄물을 대상으로 재연실험 및 DSC 및 TGA, DTA, DTG, GC/MS를 통한 열분석을 시행하여 자연발화의 가능성에 대한 과학적인 개연성을 부여하고자 하였다. 연구결과를 살펴보면 재연실험을 통하여 관찰한 결과 48시간 저장시에 온도의 급상승(178℃) 및 탄화현상, 연기발생이 관찰되었다. 또한 DTA, DTG 분석한 결과 166.15℃에서 최초중량감소가 일어나는 것으로 분석되었다. 아울러 DSC 및 TGA를 이용한 폐타이어 분쇄물 1(Unburnt)의 실험결과180℃ 부근에서 열분해를 시작하는 것으로 나타나 폐타이어의 발화 개시온도는 160~180℃라고 말할 수 있다. 그리고305℃에서 최초 원료 무게의 10 % 중량감소가 있었고, 원료 무게의 50 % 중량감소는 416℃로 분석되었다. 또한 GC/MS와 DSC를 이용한 산화성 및 자기반응성시험에 있어서는 1,3 cyclopentnadiene 등 산화성성분이 다량 검출되었지만표준물질과 폐타이어 분쇄물과의 열분석실험결과 기준치 이하로 분석되어 자기반응성은 없는 것으로 분석되었다. 따라서 폐타이어의 산화열에 의한 자연발화현상을 방지하기 위해서는 분쇄시 열축적이 적거나 없는 냉동파쇄방식 등의 가공공정으로 전환유도를 고려해야하며 현재 파쇄·분쇄물을 대형 마대(500 kg)로 저장하는 방식에서, 마대를 소형화하여 분쇄물을 분산 저장하는 등의 방법으로 열축적을 방지해야한다.

참고문헌 (Reference)

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