新拌混凝土碳封存及碳化養護之研究

Study on Carbon Sequestration and Carbon Curing of Fresh Concrete

趙伯融(Po-Jung Chao)

指導教授 ： 詹穎雯

國立臺灣大學/工學院/土木工程學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202102221

摘要

隨著科技的發展，環境汙染的問題越來越嚴重，全球暖化的議題持續延燒，全世界都在思考要如何減少溫室效應的發生，而二氧化碳是造成全球暖化很大的主因，不論是工廠排放的廢氣或者是汽機車的廢氣，這些都會使二氧化碳的濃度上升，現在有許多的科學家都在為了如何將二氧化碳封存起來而做了很多研究，希望在2050年大幅度減少二氧化碳的量。混凝土是營建產業中很常使用的材料，而且在生產水泥的過程中會排放很多二氧化碳，如果可以將二氧化碳封存到混凝土內，又可以維持良好的力學行為跟耐久性表現，這樣就可以降低整體生產過程的碳足跡。
本研究主要使用兩種方法來封存二氧化碳，第一種方法是使用氫氧化鈣去吸附二氧化碳，利用氫氧化鈣跟二氧化碳反應成碳酸鈣的原理，將生成的碳酸鈣加入水泥砂漿中，並設計不同的碳酸鈣添加量、不同的水膠比、不同的爐石取代率，搭配不同的齡期去進行單軸抗壓試驗跟乾縮試驗，以探討添加碳酸鈣對於水泥砂漿強度跟耐久性的影響，此方法會分成兩大部分，第一部分會研究氫氧化鈣吸附二氧化碳的效率，第二部分才會是後續的抗壓試驗與乾縮試驗。第二種方法是將試體去進行二氧化碳養護，將水泥砂漿試體置入於高壓的二氧化碳環境中，待養護時間結束後，進行單軸抗壓試驗，來觀測二氧化碳對於硬固試體的力學性質影響。
最後找出水化反應和碳酸鈣及二氧化碳的化學機理，比較氫氧化鈣吸附劑與二氧化碳養護兩種方法對混凝土造成的影響以及二氧化碳封存的效果與經濟性評估。

關鍵字

全球暖化 ； 碳封存 ； 碳化反應 ； 氫氧化鈣吸附行為 ； 奈米碳酸鈣 ； 二氧化碳養護

並列摘要

With the development of technology, the problem of environmental pollution is getting more and more serious. The topic of global warming is still a hot issue. How to reduce the occurrence of the greenhouse effect is the important problem. However, the carbon dioxide emissions are the main reason for global warming. The exhaust gas from manufacturing process and transportation will increase the concentration of carbon dioxide. The scientists are studying how to store carbon dioxide. They hope to significantly reduce the amount of carbon dioxide in 2050. Concrete is a very often used material in the construction industry. Moreover, it will emit a lot of carbon dioxide in the process of producing cement. If carbon dioxide is stored in concrete and it maintain good compression and durability performance, the carbon footprint of the production process will decrease.
There are two ways to store carbon dioxide in this study. The first part is to use calcium hydroxide as the adsorbent for carbon dioxide, and use the principle of calcium hydroxide and carbon dioxide to form calcium carbonate. Then, add calcium carbonate to cement mortar. Finally, design different calcium carbonate additions, different water-cementitious material ratio and different replacement rate of slag to conduct compression test and shrinkage test. The second part is carbon curing. Place the cement mortar specimen in the high-pressure carbon dioxide environment. After the carbon curing, the specimen will conduct compression test.
Finally, find out the reaction mechanism of carbon dioxide, and compare the influence of two methods on concrete and the effect of carbon dioxide storage.

並列關鍵字

global warming ； carbon sequestration ； carbonization reaction ； calcium hydroxide adsorption behavior ； nano-calcium carbonate ； carbon curing

參考文獻

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