渦旋式流體化床燃燒爐中RDF與煤炭混燒之研究

Emission Study of RDF and Coal Co-combustion in a Pilot Scale Vortexing Fluidized Bed Combustor

楊子忠(Tzu-Chung Yang)

指導教授 ： 錢建嵩

中原大學/工學院/化學工程研究所/碩士(2004年)

https://doi.org/10.6840/cycu200400660

摘要

中文摘要
台灣為一典型能源缺乏之島嶼國家，面對全球性能源匱乏問題，大量依賴進口能源已非長久之計，具自主性之再生能源實為一值得發展之方向。廢棄物衍生燃料（Refuse derived fuel，RDF）為廢棄物能源化之重要技術之一，本研究目的為探討RDF-5與燃煤於流體化床燃燒爐中混燒之可行性，藉由改變燃料配比、過量空氣比及RDF-5中添加Ca(OH)2與否，瞭解煙氣及灰渣中污染物排放之變化。煙氣中污染物以HCl、Cl2、CO、NO、N2O、SO2為主，灰渣部分則探討其中氯之殘留量，藉以判斷燃燒爐中使用RDF-5所可能產生之效應。
本研究係於一底面積0.8m x 0.4m、高4.6m之渦旋式流體化床燃燒爐中進行RDF-5與燃煤之混燒試驗，其結果顯示燃料中添加Ca(OH)2，確能降低HCl、Cl2排放濃度，鈣氯當量比達5.2以上時，HCl、Cl2排放濃度更可有效降低。高過量空氣會促進NO之生成，還有N2O生成受溫度之影響最重要。而飛灰分析中發現灰渣中之氯含量遠大於煙氣中的含量。
本實驗證實了於VFBC中以RDF與煤炭混燒之可行性。因為就實驗結果發現爐出口CO、N2O濃度為零，SOx濃度遠低於環保法規，NOx濃度亦在控制之中，唯一令人憂慮之HCl亦確定增加鈣氯比能有效降低其濃度，再輔以污染防治設備，則無污染之疑慮。床溫850℃、70％過量空氣比及5.2鈣氯當量比之操作條件下，將可使污染物排放量降至最低。

關鍵字

燃燒 ； 廢棄物衍生燃料 ； 流體化床

並列摘要

Abstract
In Taiwan, the renewable energy is getting more and more interest to practice the diverse energy policy. Therefore, one important waste- to-energy technology, co-combustion of refuse derived fuel (RDF) and coal, was investigated in this present work. The objective of this study is to discuss the feasibility of RDF co-combustion with coal from the viewpoint of pollutant emissions. The operating parameter effects on RDF combustion were investigated in a pilot scale vortexing fluidized bed combustor (VFBC). The concentration of gaseous pollutants, HCl, Cl2, CO, NO, N2O, SO2 and Dioxin were detected. Furthermore, an experimental method, response surface methodology (RSM), was used to understand the effect intensities of various operating variables and their interaction on the pollution emissions.
The experiments were carried in a pilot scale VFBC, a 0.4m×0.8m rectangular combustion chamber constructed of freeboard with 0.75m inside diameter and 4.6m in height. The co-combustion ratio, excess-air ratio, and Ca-sorbent adding ratio were investigated.
The results of this study indicated that (1) to add Ca(OH)2 into RDF as manufacturing can reduce the HCl and Cl2 concentration in flue gas; (2) the NOx concentration increases with the excess-air ratio; (3) N2O formation is sensitive to the operating temperature.
In this study, the feasibility of RDF co-combustion with coal is demonstrated. The CO、N2O、NOx、SOx concentration are much lower than the environmental regulations. The problem we mostly regarded (HCl emission) is improved effectiively by adding more Ca(OH)2. To minimize the pollutant emissions, the operating conditions with 850℃bed temperature, 70％ excess-air ratio and 5.2 Ca/Cl equivalent ratio are recommended.

並列關鍵字

RDF ； FBC ； Comboustion

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