Related Experiment Video
Updated: Sep 20, 2025
11:14
Two-way Valorization of Blast Furnace Slag: Synthesis of Precipitated Calcium Carbonate and Zeolitic Heavy Metal Adsorbent
Published on: February 21, 2017
12.5K
Recovery of valuable elements from coal fly ash: A review
Xiaoman Tian1, Zhengqi Guo1, Deqing Zhu1
1School of Mineral Processing and Bioengineering, Central South University, Changsha, 410083, Hunan, China.
Environmental Research
|May 26, 2025
Summary
Coal fly ash, a waste product, contains valuable elements like rare earth elements. Recovering these elements offers a sustainable solution for resource scarcity and waste management.
Area of Science:
- Materials Science
- Environmental Engineering
- Chemical Engineering
Background:
- Coal fly ash is a significant solid waste from coal combustion, posing environmental risks and disposal challenges.
- It contains valuable elements such as Al, Si, Fe, Li, Ga, and rare earth elements, presenting utilization potential.
- Global depletion of mineral resources and limited rare earth element availability necessitate alternative sources.
Purpose of the Study:
- To comprehensively review the composition, distribution, and forms of elements in coal fly ash.
- To evaluate current and novel methods for recovering valuable elements from coal fly ash.
- To discuss sustainable utilization strategies for coal fly ash.
Main Methods:
- Review of physical beneficiation, hydrometallurgy, and pyrometallurgy techniques.
- Analysis of novel processes for element recovery.
- Evaluation of methods based on energy consumption, efficiency, and environmental impact.
Main Results:
- Detailed summary of elemental composition, content, distribution, and forms in coal fly ash.
- Comparative analysis of various recovery methods, highlighting their pros and cons.
- Identification of key challenges and opportunities in coal fly ash utilization.
Conclusions:
- Recovery of valuable elements from coal fly ash is crucial for resource sustainability and waste management.
- Developing comprehensive, eco-friendly, and low-energy recovery technologies is essential.
- Promoting the utilization of coal fly ash supports green economic development.
Related Concept Videos
01:21Pozzolans
204
Pozzolans are siliceous or aluminous materials blended with Portland cement. They interact with the calcium hydroxide produced during the hydration of Portland cement and contribute to improved strength and durability of concrete. The pozzolanic activity, a measure of a pozzolan's effectiveness, is typically assessed using the strength activity index, as defined in ASTM C 618-93, which calculates the ratio of the compressive strength of cement mixtures with and without pozzolan.
Fly ash is...
Fly ash is...
204
01:08Sample Preparation for Analysis: Advanced Techniques
468
Accurate analysis of complex samples often requires advanced preparation techniques to achieve reliable and reproducible results. Samples containing inorganic or organic materials can be challenging to dissolve or decompose effectively. Standard sample preparation methods include acid digestion, fusion, dry ashing, and wet digestion.
Acid digestion with strong acids is commonly used to dissolve inorganic materials that are insoluble (do not dissolve) in water. This method can be useful for...
Acid digestion with strong acids is commonly used to dissolve inorganic materials that are insoluble (do not dissolve) in water. This method can be useful for...
468
01:29Additives and Fillers in Concrete
137
Additives and fillers are integral to enhancing the properties of concrete. Pozzolans and blast-furnace slag are additives or admixtures due to their reactions with calcium hydroxide released during cement hydration. Fillers, which are finely ground and similar in fineness to Portland cement, improve concrete attributes such as workability density, and reduce capillary bleeding or cracking. Some fillers possess hydraulic properties or participate in benign reactions within the cement paste.
The...
The...
137
01:21Portland Cement
310
Portland cement is the essential binding ingredient in concrete, made from finely ground materials including lime, iron, silica, and alumina. Lime is derived primarily from limestone, marble, marl, seashells, and clays, which also supply iron and alumina, while silica is sourced from sand, chalk, and bauxite. Contemporary manufacturing of Portland cement is a significant source of carbon dioxide emissions, prompting research into reducing its content in concrete through alternative...
310
01:25Deleterious Substances in Aggregate
272
Deleterious substances in aggregates can be detrimental to the quality and durability of concrete. These substances include organic impurities like loam, which interfere with cement hydration and are usually present in the sand. These prevent a good bond between aggregate and cement paste. Organic impurities can be detected using the colorimetric test, where the darkness of a solution after agitation indicates the level of organic content.
Another type of impurity is clay and fine material that...
Another type of impurity is clay and fine material that...
272