以藻類去除半導體業廢氣中二氧化碳之可行性研究

Evaluation of removal carbon dioxide emissions from the semiconductor industry by algae

王冠翡(Kuan-fei Wang)

指導教授 ： 李俊福

國立中央大學/工學院/環境工程研究所碩士在職專班/碩士(2011年)

摘要

全球人口不斷的增加，對於整體環境與生態資源也造成越來越大的壓力，人類科技發展及經濟活動為環境更帶來了重大的影響，大量的溫室氣體排放造成全球各地天然災害頻傳、氣候變遷、能源的枯竭、糧食的缺乏，而溫室氣體中又以二氧化碳為首，所以如何盡快遏止大氣中二氧化碳濃度之升高，以減緩劇烈變動之環境氣候，成為重要的課題。
國內在政府機關的帶動下，不管是工商業或家庭，降低能源損耗的觀念已漸漸深植人心。各企業亦了解經濟與環保雙贏才能達到永續發展，在各項的研究中，以生物方式進行減碳機制，被認定為是一種對環境衝擊最低，也是最具永續成長潛能的方式。目前世界各國最普遍的生物減碳方式即為植樹，利用樹木對二氧化碳的自然吸收機制，達到減碳的目的，然而植樹造林必須等數十年才可發揮功能，且其吸收二氧化碳的效率卻遠低於人類製造溫室氣體的速度。故近年來，利用藻類或微生物的光合作用進行減碳的研究日漸受到重視；藻類與陸生能源作物相比，具有生長快速，固碳效率高之優點，藻類光合作用可以把無機的二氧化碳轉換成生物性碳氫化合物，進一步可做為飼料、肥料及燃料等再加以利用，是最具永續成長潛能的無污染減碳方式。
本研究以結合產業與學術共同減少碳排放為出發點，評估以藻類進行工廠廢氣碳捕集之可行性，以半導體廠天然氣燃燒鍋爐的廢氣做為碳源，採用薄板直立式的光合反應器進行藻類養殖，與傳統藻類養殖相較，具有設置佔地面積小及地點限制少之優點，適合一般工廠設置，再加上夜間以LED燈源提供照明，可延長藻類光合作用進行碳轉換反應時間，較傳統養殖增加減碳成效。本研究以在二氧化碳分析儀得到40Hz下，可達25%之最佳二氧化碳洗滌效率，0.1NNaOH為最適合之洗滌濃度，藻種以螺旋藻(Spirulina maxima)養殖成長效果較佳，養殖濃度則以pH值8時，藻類生長量為最大。另外，稀釋比例為0.2(1/5倍)之稀釋條件，可得到較高的產藻量，惟補助光源LED照射效果較無明顯效果。本研究微藻養殖的碳源來自工廠廢氣，除可提供藻類生長所需營養源外，亦可直接達到降低工廠二氧化碳(CO2)排放的減碳效益，同時藻類產出後可作為有經濟價值之後續利用，整體達到環保、減碳、經濟等三個層面的效益。

關鍵字

半導體業 ； 微藻 ； 二氧化碳減量

並列摘要

The global population continues increasing, which increases the human technological development and economic activities for the environment. It also brought a significant impact on a lot of greenhouse gas emissions caused by frequent natural disasters around the world, climate change, energy depletion, lack of food, and rise in carbon dioxide concentration, which changes in environment and climate.
The industrialists realized to make a strategy for both economy and environment in order to achieve sustainable development. The biological approach of environmental restoration, has been identified as a minimum impact on the environment, but also the most sustainable way of potential growth. The most popular functionality adopts to reduce carbon dioxide presence in the global is planting trees. Planting trees is the best way to restore the surface of the natural ecology so far. Unfortunately, the efficiency of absorption of carbon dioxide is far lower than the rate of human-made greenhouse gases. Nowadays, using algae or microbial photosynthesis to cut carbon emissions has received increased attention. To contrast with terrestrial energy, the advantage of algae is its fast-growing, and the high efficiency of carbon fixation. The algae photosynthetic biological fixation ability can be transformed from carbon dioxide to hydrocarbons, and it also can be used as feed, fertilizer, fuel, etc. It has not only been considered to be a minimum impact on the environment, but also is the most sustainable growth potential of the carbon pollution reduction methods.
In this study, to work cooperatively with industries and academic, to improve the global warming as a starting point, to reduce the carbon emissions as the purpose of assessing plant emissions, to evaluate algae for carbon capture of the feasibility study with boiler combustion exhaust gas as a carbon source at semiconductor plant, the thin plate vertical reactor to conduct the photosynthetic algae cultivation, and the harvest equipment for thin-film algae concentrated harvest have been focused. The traditional farming algae, with small footprint, combined with LED light source to provide lighting to extend the algae photosynthesis reaction time and required nutrient source. We found that Carbon Dioxide Meter with 40 Hz performed the best carbon dioxide removal effiiciency by 25%. The optimum operation conditions are 0.1NNaOH, and the cultivation algae of Spirulina maxima had the best growth effect, the algae grew most with a pH value of 8. A dilution ratio of 0.2(one-fifth time) has a higher algae production. However, the auxiliary LED light source didn’t have positive effect. The most important is carbon emissions from the plant, which provides for growth of algae and they can also reduce carbon dioxide (CO2) emissions directly based on the whole to achieve environmental protection, carbon reduction, and economical beneficial result.

並列關鍵字

CO2 Reduction ； Logistic model ； Semiconductor Indus

參考文獻

11.行政院環境保護署環署空字第0940106804號，室內空氣品質排放標準

33.何佩樺，『我國溫室氣體減量策略之環境與經濟影響評估-以能源稅為例』，中原大學碩士論文，2010年

1.Cheng L., Zhang L., Chen H., Gao C. (2006) Carbon dioxide removal from air by microalgae cultured in a membrane-photobioreactor. Separation and Purification Technology 50:324–329.

2.Kurano N., Ikemmoto H., Miyashita H., Hasegawa T., Hata H., Miyachi S. (1995) Fixation and utilization of carbon dioxide by microalgal photosynthesis. Energy Convers. Mgmt 36: 689-692.

3.Yue L., Chen W. (2005) Isolation and determination of cultural characteristics of a new highly CO2 tolerant fresh water microalgae. Energy Convers. Mgmt 46:1868–1876.