Resource utilization of calcium-based desulfurization ash in flue gas: a comprehensive review

Calcium-based desulfurization ash (CDA) is mainly produced in dry and semi-dry flue gas desulfurization processes. The property of CDA is extremely unstable because its main component, calcium sulfite, makes it difficult to be directly applied to the field of building materials. The modification of desulfurization ash can be realized by high-temperature oxidation and wet oxidation. After modification, CDA can be widely used in building materials. Hydrothermal oxidation has broad development prospects because it can complete the oxidation of CDA and the removal of impurity elements at the same time. CDA can be used to prepare high value-added products of calcium sulfate whiskers and ecological rubber fillers.

Automated summary

Calcium-based desulfurization ash (CDA) is mainly produced through dry and semi-dry flue gas desulfurization processes. Its main component, calcium sulfite, makes CDA unstable and unsuitable for direct use in building materials. CDA can be modified through high-temperature oxidation and wet oxidation, and the modified CDA can be widely used in building materials. Hydrothermal oxidation shows great potential as it allows for the oxidation of CDA and the removal of impurities simultaneously. CDA can be used to produce high value-added products such as calcium sulfate whiskers and ecological rubber fillers.