醫療廢棄物於先導型氣泡式流體化床燃燒爐之焚化

Incineration of Medical Waste in a Pilot Scale Bubbling Fluidized Bed Combustor

黃丞佑(Cheng-You Huang)

指導教授 ： 錢建嵩

中原大學/工學院/化學工程研究所/碩士(2019年)

https://doi.org/10.6840/cycu201900007

摘要

醫療院所產生之廢棄物因其本身具有危害性，而不可進行切割、破碎等前處理之動作，必須採取批式方式進料於焚化爐中進行燃燒，以防止有害物質外洩造成危害，而大多數流體化床燃燒爐多以連續進料燃燒，為模擬醫療廢棄物之進料行為，因此本實驗係選用批式進料進行實驗。
本研究於一總高4.6 m，燃燒室為0.8 × 0.4 m ，乾舷區內徑0.75 m之先導型渦旋式流體化床燃燒爐中以不同氯含量之模擬醫療廢棄物(0.037%, 0.1%, 1%, 2%)、不同進料時間間隔(1 batch/3min, 1 batch/4min, 2 batch/6min)以及額外使用連續進料系統添加碳酸鈣進行研究，模擬物以造粒之稻稈以及聚氯乙烯(Polyvinyl Chloride, PVC)粉末填入一硬紙板圓柱容器中，其直徑與高分別為10、34 cm，於乾舷區安裝一柴油燃燒機使其溫度維持850oC以上，以探討不同操作條件對於燃燒行為以及污染物排放之影響。
實驗結果顯示物質進料後爐內溫度有先上升後下降之週期變化，增加進料時間間隔或每批次進料量及進料時間間隔對平均乾舷區溫度及床區振幅有上升之趨勢，平均CO濃度則有下降之現象，氯含量為2%時有較高之平均乾舷區溫度及振幅，添加碳酸鈣係有阻礙點火及燃盡之現象產生，進料物質氯含量於1%以上或添加碳酸鈣之實驗，戴奧辛之濃度有明顯上升，其中戴奧辛同源物中以呋喃為主，又以2,3,4,7,8-PeCDF為最大毒性提供者。

關鍵字

流體化床 ； 批式進料 ； 戴奧辛

並列摘要

Medical waste is regarded as infectious waste and generated from the medical activities. The packed container of medical waste must not be destroyed to prevent the hazardous material from spreading into the environment. However, most of fluidized bed combustion system was operating using continuous feeding system. So, we want to investigate combustion of simulated medical waste in a vortex fluidized bed combustor using a batch feeding system.
The combustion chamber of combustor with a cross-section of 0.8 m × 0.4 m and the freeboard is 0.75m in inner diameter. The simulated medical waste, consisting rice straw RDF, PVC powder, was encapsulated in a cylinder made by paper. The outside dimension of the cylinder is 34cm length with an ID of 10 cm. The temperature kept at 850 oC by diesel burner in the freeboard. The operating parameters including interval time of feeding (3min, 4min, 6min/2batch), different content of chlorine in feeding material (baseline, 0.1%, 1%, 2%) were studied.
The experimental results show that the bed and freeboard temperature vary periodically. The highest temperature of the combustor takes place in freeboard zone. The mean freeboard temperature and amplitude of bed temperature increases with interval time. The combustion temperature is hindered by adding of Calcium carbonate. When chlorine content exceed 1% or adding of Calcium carbonate, the concentration of dioxin in fly ash apparently increase. The PCDFs are dominating in the PCDD/Fs in our combustion system.

並列關鍵字

Fluidized bed ； Batch feeding ； PCDD/Fs

參考文獻

參考文獻

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