A novel Ti-based sorbent for reducing ultrafine particulate matter formation during coal combustion

Influences of In-Furnace Kaolin Addition on the Formation and Emission Characteristics of PM2.5 in a 1000 MW Coal-Fired Power Station

“…Meanwhile, PM samples collected on the polycarbonate membranes were analyzed via an X-ray fluorescence probe (XRF, EAGLE III, EDAX Inc.) and a field emission scanning electron microscope coupled with energy dispersive X-ray analyzer (FESEM-EDX, Sirion 200, FEI Inc.) to characterize their micromorphology and chemical composition characteristics. Prior to the observation under FESEM, a thin layer of platinum (Pt) was coated onto the samples to improve their conductivity . To ensure the reproducibility of the data, three parallel runs were conducted under each condition, with the average values and error bars being reported.…”

“…PM 2.5 (particulate matter with the aerodynamic diameters of ≤2.5 μm), which is enriched in hazardous components and harmful to human beings, has become one of the most concerned air pollutants. − China is suffering a severe PM 2.5 pollution, and coal-fired power stations are one of the primary PM emission sources. , Currently, various PM removal devices/technologies such as electrostatic precipitators (ESPs) are equipped downstream of the boilers to dedust the flue gas. , However, these dust collectors cannot effectively remove the fine and ultrafine PM. − To handle this troublesome PM, various methods improving the performance of dust collectors have been tried, yet they are generally costly. − In recent years, a novel in-furnace PM reduction technology based on additive(s) has been proposed and rapidly developed. − The “de-PM” additives are designed to reduce the formation of fine/ultrafine PM during the combustion process and thereby make up for the deficiencies of the dust collectors. In this way, this technique could strengthen the emission control of the fine PM in a targeted manner, and help the power stations meet emission requirements at lower costs.…”

“…Existed studies in this area are mainly carried out on the bench/pilot scale reactors and focused on the screening of additives, ,, their PM capture mechanism ,− and performance under different combustion conditions (e.g., temperature, atmosphere, fuel properties, etc. ). − Clay mineral kaolin is regarded as the most practically feasible one in the future industrial application.…”

“…On the one hand, the added kaolin would react with the gaseous PM precursors (e.g., Na-contained mineral vapor, etc.) and inhibit their partitioning into the fine PM. ,,, On the other hand, some products of kaolin would melt during the high-temperature combustion process and form liquidus substance, which captures the PM via collision and aggregation. , The performance of kaolin on reducing the formation of fine PM is of the highest level of all the reported additives; however, it would change with the specific work conditions. It is reported that its PM capture efficiency would significantly decrease when the temperature exceeds 1373 K because of the melting/sintering phenomenon, indicating a high sensitivity to temperature. , The effects of combustion atmosphere on the performance of kaolin are more complicated.…”

“…and inhibit their partitioning into the fine PM. 14,16,19,21 On the other hand, some products of kaolin would melt during the high-temperature combustion process and form liquidus substance, which captures the PM via collision and aggregation. 18,20 The performance of kaolin on reducing the formation of fine PM is of the highest level of all the reported additives; however, it would change with the specific work conditions.…”