Improving the removal of inhalable particles by combining flue gas condensation and acoustic agglomeration

Particulate matter emission reduction in small- and medium-scale biomass boilers equipped with flue gas condensers: Field measurements

“…The change in particle size is due to three processes, namely heterogeneous nucleation, condensation growth and agglomeration. First, the temperature gradient between the flue gas and the cooling water will create a zone of supersaturated water vapour near the tube wall in which fine particles act as condensation nuclei for heterogeneous nucleation [28,29]. Second, particles in this supersaturated zone will grow by heterogeneous condensation [29][30][31].…”

“…First, the temperature gradient between the flue gas and the cooling water will create a zone of supersaturated water vapour near the tube wall in which fine particles act as condensation nuclei for heterogeneous nucleation [28,29]. Second, particles in this supersaturated zone will grow by heterogeneous condensation [29][30][31]. Although a higher supersaturation is required for vapour to condense on small particles than on large particles [17], film covered particles (like particles that result from heterogeneous nucleation) become much easier for condensation growth compared with the same sized particles without film [29].…”

“…Second, particles in this supersaturated zone will grow by heterogeneous condensation [29][30][31]. Although a higher supersaturation is required for vapour to condense on small particles than on large particles [17], film covered particles (like particles that result from heterogeneous nucleation) become much easier for condensation growth compared with the same sized particles without film [29]. Thirdly, particle agglomeration may be enhanced by the bound effect of the liquid bridge formed between particles covered with a liquid film [29,31].…”

“…Although a higher supersaturation is required for vapour to condense on small particles than on large particles [17], film covered particles (like particles that result from heterogeneous nucleation) become much easier for condensation growth compared with the same sized particles without film [29]. Thirdly, particle agglomeration may be enhanced by the bound effect of the liquid bridge formed between particles covered with a liquid film [29,31]. The particle depositions are mainly attributed by Brownian diffusion losses, inertial losses, interception, thermophoresis and diffusiophoresis.…”

Theoretical model and dynamic wave-amplification effect of the high intensity Helmholtz sound source

“…Aerodynamic high-intensity sound as an effective wave energy form has meaningful potential applications in many different industrial technical fields. Main applications contain the dust-cleaning of solar panel (Abubakar et al, 2020), the soot-blowing of coal-fired utility boiler (Xu et al, 2021), the acoustic levitator (Andrade et al, 2019), the acoustic dust-separation of flue gas (Karpul et al, 2010), the acoustic agglomeration of dust collector (Li et al, 2020), the atmospheric rainfall/defogging (Shi et al, 2021), the fire smoke elimination (Zhang et al, 2020), and so on. These acoustic applications play a significant role in advancements of science and technology.…”