污泥中的性控制推动了混凝土泥渣废物的转化为微和纳米尺寸的生物 CaCO
Jinbo Zhao1, Jiacheng Feng2, Yifan Du2
1School of Civil Engineering, Chang'an University, Xi'an 710054, China; State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
概括
本研究引入了一种使用活性污泥和混凝土泥渣废物生产生物碳酸 (bio-CaCO3) 的新方法. 这一过程增强了碳捕获,并提供了一种可持续的混凝土修复方法.
科学领域:
- 环境微生物学 环境微生物学
- 材料科学 材料科学 材料科学
- 生物技术是生物技术.
背景情况:
- 微生物诱导的碳酸沉 (MICP) 被认为是具体的应用.
- 之前的MICP研究没有利用活性污泥或混凝土污泥废物 (CSW).
研究的目的:
- 调查使用活性污泥和CSW用于微/纳米碳酸 (CaCO3) 生产的潜力.
- 探索使用污泥微生物β-氧化和CSW的MICP的可行性.
主要方法:
- 在性条件下从CSW中利用的和污泥微生物β-氧化中的碳.
- 优化pH值以促进CaCO3沉和碳捕获.
- 分析了沉的CaCO3.3的晶体形式,颗粒大小和重金属含量.
- 确定了参与该过程的占主导地位的微生物类和属.
主要成果:
- 产生的微/纳米CaCO3与石作为主要的晶体形式 (0.710微米颗粒).
- 在最佳pH (8.59) 达到高碳捕获 (743毫克L-1) 和CaCO3生产 (1,191毫克L-1).
- 鉴定出蛋白质细菌和细菌杆菌为主导类,其中Thauera属擅长β-氧化.
- 在上游物中发现了极少的重金属.
结论:
- 性条件促进微生物β-氧化,二氧化碳生产和CaCO3沉.
- 本研究提出了一种使用CSW的基于污泥的MICP的新方法.
- 该方法为碳捕获和混凝土材料增强提供了一个可持续的途径.
相关概念视频
01:26Alkali Aggregate Reaction in Concrete
92
The alkali-aggregate reaction in concrete involves natural siliceous minerals in aggregates reacting with alkaline hydroxides derived from cement alkalis. This reaction forms an alkali-silica gel that absorbs water, swells, and increases in volume, which is confined by the surrounding cement paste, creating internal pressures that crack and disrupt the concrete. The extent of expansion and damage can be partly attributed to the alkali-silica reaction's osmotic hydraulic pressure and the...
92
01:24Carbonation Shrinkage
121
Atmospheric CO2 penetrates the concrete's pores and, in the presence of moisture, forms carbonic acid, which then reacts with calcium hydroxide in the hydrated cement, forming calcium carbonate. This process reduces the concrete's volume and is termed carbonation shrinkage.
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction...
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction...
121
01:21Acid Attack on Concrete
196
When acids come into contact with concrete, they initiate a chemical reaction that dissolves the hydrated cement paste. This process leads to softening and structural weakening of the concrete. This issue is commonly observed in environments such as chimneys, sewers, and industrial settings. The severity of the damage increases as the pH of the water interacting with the concrete drops below 6.5. In particular, a pH under 4.5 can cause significant concrete damage.
The rate at which hydrogen...
The rate at which hydrogen...
196
01:29Sulfate Attack on Concrete
121
Sulfate attack on concrete is a deterioration process characterized by a whitish discoloration beginning at the edges and corners, accompanied by cracking and spalling. This phenomenon occurs when sulfates react with the components of hardened concrete, forming compounds like calcium sulfate and calcium sulfoaluminate which occupy more space than the substances they replace, causing the concrete to expand and disrupt.
Sulfates from sources like soil, groundwater, or industrial effluents...
Sulfates from sources like soil, groundwater, or industrial effluents...
121
01:24Hydration of Cement
207
Hydration of cement is a chemical reaction between cement particles and water. This process occurs primarily through two mechanisms: through-solution and topochemical. In the through-solution process, anhydrous compounds dissolve into their constituents, hydrates form in the solution, and then precipitate from the supersaturated solution. The topochemical process involves solid-state reactions at the cement particle surface. The through-solution process dominates the topochemical process at the...
207
01:19Quality of Water
89
In concrete preparation, the quality of water is paramount as it affects the strength and durability of the concrete. Potable water is usually preferred; however, it must not have excessive sodium or potassium to prevent compromising the concrete's integrity. Water quality is typically evaluated based on impurities such as dissolved solids, chlorides, and sulfates, and its pH value is ideally between 6 and 8. Even slightly acidic natural water may be acceptable unless it contains harmful...
89