機車觸媒引擎污染物排放影響與其活性劣化再生之研究

The study of popllution conversion and regeneration of used motorcycle catalysts

張元義(Yuan-Yi Chang)

指導教授 ： 林文印

國立臺北科技大學/工程學院/環境工程與管理研究所/碩士(2008年)

https://doi.org/10.6841/NTUT.2008.00406

摘要

由於台灣單位面積車輛數過多，以及都市環境走走停停之車況，且駕駛人缺乏對汽機車之保養維修工作之習慣，導致汽機車成為空氣污染的重要來源之一，其所產生之各種污染物對人體及環境皆造成相當大危害，另外，駕駛超過觸媒有效使用期限的車輛，由於排放控制系統效率低，產生了更多的空氣污染到大氣中。
國內對於觸媒之研究，雖已有針對工業用觸媒進行實驗，但只著重於探討觸媒中貴金屬之分佈特性，對於機車觸媒再生之實用性，與機車觸媒實際處理引擎污染物之情形則無相關研究探究。
有鑑於此，本研究試利用四行程機車引擎、引擎動力計、電子低壓衝擊器 (Electrical Low-Pressure Impactor, ELPI)、微孔均勻沈積衝擊器 (Micro-Orifice Uniform Deposit Impactor, MOUDI)、車輛廢氣分析儀 (Automotive emission analyzer) 等，建立機車引擎排放之氣狀、粒狀污染物採樣系統，並搭配離子層析儀 (Ion Chromatography, IC) 及元素分析儀 (Element Analyzer, EA)，分析機車引擎排放之粒狀物質在觸媒再生前、後之條件下，對於不同粒徑微粒之組成成分影響，以進一步建立機車觸媒活性再生之相關資訊。
由研究結果顯示，觸媒經過不同之溫度將活性再生後，可發現隨著再生溫度的提高，於觸媒前後之污染物濃度變化逐漸增加，其中以碳氫化合物 (HC) 受到之影響最為顯著。觸媒再生之效率隨著加熱溫度增加而增加，經甲烷再生後之觸媒處理效率由原本 4.8% 提升到 71.06%，而經過氫氣再生後之觸媒處理效率則由原本的 14.2% 提升為 43.44%。本研究所使用之四行程機車引擎在惰轉時，於觸媒轉化器之前所測得微粒之數目濃度大約在 5×1000000 ~ 7×1000000 (#/cm3) 之間，而在觸媒轉化器之後所測得微粒之數目濃度大約在 3×10000 ~ 4×100000 (#/cm3) 之間，結果顯示觸媒轉化器對引擎排放微粒之數目濃度具有一定之去除率。

關鍵字

機車 ； 劣化觸媒 ； 觸媒還原 ； 活性再生處理技術

並列摘要

In addition to high density of vehicle number per unit land area in Taiwan, the driving conditions are not very well in the city. Furthermore, poor inspection and maintenance cause the vehicles to become one of the important sources of air pollution. Different kinds of pollutants emitted from vehicle pose serious effects to human health and the environment. Moreover, driving vehicle with low control efficiency catalyst generates more air pollutions into atmosphere.
In Taiwan, the study of catalyst has been researching about industrial catalyst but merely focused on dispersion of the noble metal. The feasibility of catalyst activation regeneration technology of the motorcycle was not well discussed.
According to these reasons, we used the four-stroke motorcycle engine (125 c.c.), dynamometer, electrical low-pressure impactor (ELPI), micro-orifice uniform deposit impactor (MOUDI) and automotive emission analyzer to set up the engine pollutants measurement. An Ion Chromatography (IC) and an Element Analyzer (EA) were used to analyze characterization of particles before and after regeneration of deactivated catalyst.
The results suggested that catalyst activation increased as regeneration temperature increased. The catalyst efficiency increased from 4.8% to 71.06% after regeneration by CH4 and the catalyst efficiency increased from 14.2% to 43.44% after regeneration by H2. When rotational speed at idle, the number concentration was 5×1000000 ~ 7×1000000 #/cm3 upstream catalyst and the number concentration was 3×10000 ~ 4×100000 #/cm3 downstream catalyst. The results suggested that catalytic converter can cause number concentration low.

並列關鍵字

motorcycle ； de-activated catalyst ； regeneration ； Regenerated treatment technology of the catalyst activation

參考文獻

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