ホウ素含有モデル燃焼排ガスを用いた凝縮性ナノ粒子生成挙動

摘要

大気中で浮遊性が高く，肺深部へ到達する可能性が高い，粒子径2.5μm以下の粒子はPM2.5と呼ばれ，呼吸器系疾患など健康影響を及ぼすことが懸念されており，日本では2009年9月にPM2.5の大気環境基準が制定された。%In order to discuss the generation and release mechanism of condensable nanoparticles derived from boron in coal at combustion processes, model flue gases with boron containing vapor, spherical silica particles and their mixture were introduced to a diluter and mixed with clean air. Size distribution of diluted samples determined by a DMA system showed a broad peak at around 70 nm for boron containing systems. The peak corresponded to aggregates of spherical 20～30 nm particles as observed by FE-SEM. With addition of silica aerosol, number concentration of boron condensed aggregate peak was a little lowered and boron derived particles were observed onto silica aerosol surfaces.