Ceramic filters for high-temperature flue gas filtration and their regeneration: A review of the current state of knowledge

The combustion of solid fuels in combustion devices produces pollutants that have a negative impact on human health and the environment. One way to reduce the concentration of sub-micron particulate matter (PM) in the flue gas is to filter the flue gas using ceramic filters. Their main advantage, compared to other flue gas cleaning methods, is the possibility of using them at high flue gas temperatures (>400°C). This review article presents an overview of research articles published mainly between 2020 and 2023 on flue gas filtration using ceramic filters (candles, membranes, foams, and discs) and on their regeneration. Ceramic filters are used in many flue gas cleaning applications where the cleanliness of hot flue gas is required. Their inclusion in the flue gas path is associated with increased energy consumption for forced exhaust and pressure pulse filter regeneration. The review also includes an introduction to the materials and methods used to manufacture the filters and to test their effectiveness. This review provides a comprehensive overview of the current state of knowledge on ceramic filters. Specifically, the focus is on the filtration efficiency, pressure drop, and regeneration of the ceramic filters under consideration.