DC 欄位 |
值 |
語言 |
DC.contributor | 化學工程與材料工程學系 | zh_TW |
DC.creator | 陳朝鈺 | zh_TW |
DC.creator | Chao-Yuh Chen | en_US |
dc.date.accessioned | 2004-7-13T07:39:07Z | |
dc.date.available | 2004-7-13T07:39:07Z | |
dc.date.issued | 2004 | |
dc.identifier.uri | http://ir.lib.ncu.edu.tw:444/thesis/view_etd.asp?URN=86341008 | |
dc.contributor.department | 化學工程與材料工程學系 | zh_TW |
DC.description | 國立中央大學 | zh_TW |
DC.description | National Central University | en_US |
dc.description.abstract | 因工業快速地發展,使能源之消耗特別是石油消耗劇增,空氣污染也日益嚴重,過量二氧化碳氣體排放所引發的溫室效應,已經成為嚴重的國際污染問題。二氧化碳的排放主要來自於石化工業的燃燒,由於世界性公約的限定,未來二氧化碳排放量勢必得較目前降低。減緩二氧化碳排放量是首要工作,而將回收後的二氧化碳再生利用則是後續所需開發的工作,本論文為利用變壓吸附相關程序探討二氧化碳回收與再生利用的研究,文中共分成三部分進行探討。
第一部份為藉由實驗探討兩種不同的雙塔式真空變壓吸附程序,並由脫附步驟得到濃縮的二氧化碳氣體。就脫附步驟中的二氧化碳產物濃度而言,六步驟程序可得到較四步驟程序為高的二氧化碳產物濃度,在脫附步驟中的二氧化碳產物濃度會隨檢測時間的增加而上升,二氧化碳濃度最高可達將近90%,二氧化碳的回收率則介於90%到95%之間。
第二部分首先利用實驗與模擬結果驗證程式的可行性,再利用模擬方式進行雙塔和三塔程序的探討,依據模擬結果可知,三塔程序在濃縮二氧化碳的效果上,確實比雙塔程序佳,但是在雙塔程序中可以得到較高的二氧化碳回收率。在三塔程序的結果中可知,當壓力超過1.5大氣壓後,脫附步驟中的二氧化碳濃度不再增加,此外,在最佳操作條件下,二氧化碳濃度可以濃縮至約63%,此時二氧化碳回收率為67%。
依據勒沙特列原理(Le Châtelier principle),平衡控制的反應可藉由選擇性移出某些反應產物以增加反應物的轉化率,此觀念被應用在變壓吸附反應器中,變壓吸附反應器為結合反應與吸附的程序,此外,變壓吸附反應器還有省能與低操作溫度的優點。第三部份為利用兩種三步驟單塔變壓吸附反應器程序探討二氧化碳的再生利用,以逆水氣反應(reverse water gas shift)為探討的反應,藉由探討各種操作變數(例如步驟時間、塔長與進料壓力等)對轉化率的影響,尋找較佳的操作條件。由模擬的結果可知,二氧化碳的轉化率最高可達至約70%,此外,增加沖洗氣體量可以有效降低沖洗步驟時間。 | zh_TW |
dc.description.abstract | Because of the fast industry development, energy consumption, especial petroleum consumption, is increasing rapidly and air pollution becomes more and more serious. Greenhouse effect due to excess carbon dioxide emission becomes an international pollution problem. Carbon dioxide released into the atmosphere is mainly attributed to fossil fuel combustion. The amount of carbon dioxide emission has to be cut down in the future due to global treaty. Though mitigation of the release of carbon dioxide is important, reuse of carbon dioxide is the following work that has to be done. Carbon dioxide recovery and utilization by pressure swing adsorption (PSA) related processes are explored in this study. This study is divided into three parts.
The first part of this study is to employ dual-bed vacuum swing adsorption (VSA) processes for CO2 removal from flue gas and concentrates CO2 in desorption stream experimentally. The CO2 product concentration in desorption step in the six-step process is higher than that in the four-step process. The outlet CO2 concentration in desorption step increases with detection time. The highest CO2 concentration can be near 90%. The recovery of CO2 is between 90% and 95%.
In the second part, the VSA simulation program is convinced of its feasibility by the comparison of experimental results and simulation results. Both dual-bed and three-bed processes are explored by simulation. The effect on concentrating carbon dioxide is better in the three-bed process than in the dual-bed process, but carbon dioxide recovery is higher in the dual-bed process. Increasing feed pressure is not always advantageous to concentrate carbon dioxide in the three-bed VSA process. Carbon dioxide concentration in desorption stream does not change when feed pressure is over 1.5 atm. In the optimum operation condition, 63% carbon dioxide can be attained, and carbon dioxide recovery is 67% in the three-bed process.
Based on Le Châtelier principle, the conversion of reactants to products can increase when some products are removed selectively from the reaction zone. This concept is used in pressure swing adsorption reactor (PSAR). PSAR is a combination of reaction and adsorption process. In addition, PSAR can save energy with lower process operating temperature. The third part in this study explores the carbon dioxide utilization by two kinds of single-bed PSAR processes. Reverse water gas shift reaction is considered here. The change of operation parameters, such as step time, bed length, and feed pressure, etc., is explored to find the optimum operation condition. According to the simulation results, carbon dioxide conversion can be near 70% at the optimum condition. Increasing purge gas volume is also an effective method to reduce step time of the purge step in processes. | en_US |
DC.subject | 二氧化碳 | zh_TW |
DC.subject | 變壓吸附 | zh_TW |
DC.subject | 再生利用 | zh_TW |
DC.subject | 溫室效應 | zh_TW |
DC.subject | pressure swing adsorption | en_US |
DC.subject | greenhouse effect | en_US |
DC.subject | carbon dioxide | en_US |
DC.subject | utilization | en_US |
DC.title | 利用變壓吸附相關程序探討二氧化碳
回收與再生利用之研究 | zh_TW |
dc.language.iso | zh-TW | zh-TW |
DC.title | Study of Carbon Dioxide Recovery and Utilization by Pressure Swing Adsorption Related Process
| en_US |
DC.type | 博碩士論文 | zh_TW |
DC.type | thesis | en_US |
DC.publisher | National Central University | en_US |