This paper reports the effect of water vapour on particulate matter (PM) during the separate combustion of in situ volatiles and char generated from chromated-copper-arsenate-treated (CCAT) wood at 1300 °C. Combustion of in situ volatiles produces only PM with aerodynamic diameter <1 µm (i.e., PM₁), dominantly PM with aerodynamic diameter <0.1 µm (i.e., PM_0.1). Water vapour could significantly enhance the nucleation, coagulation and condensation of fine particles and reduce the capture of Na and K by the alumina reactor tube via reduced formation of alkali aluminates, leading to increases in both yield and modal diameter of PM_0.1. Water vapour could also enhance char fragmentation hence increase the yield of PM with aerodynamic diameter between 1 and 10 µm (i.e., PM_1–10) during char combustion. For trace elements, during in situ volatiles combustion, volatile elements (As, Cr, Ni, Cu and Pb) are only presented in PM₁ and water vapour alters the particle size distributions (PSDs) but has little effect on the yields of these trace elements. During char combustion, As, Cr, Cu and Ni are present in both PM₁ and PM_1–10 while the non-volatile Mn and Ti are only present in PM_1–10. Increasing water vapour content increases the yields of As, Cr, Cu, Ni, Mn and Ti in PM_1-10 due to enhanced char fragmentation. During char combustion, water vapour also originates less oxidising conditions locally for enhancing As release, promotes the generation of gaseous chromium oxyhydroxides and inhabits the production of NiCl₂ (g), leading to increased yields of As and Cr and decreased yield of Ni in PM_0.1.

本文报道了在1300°C的条件下，原位挥发物和由铬酸铜-砷化砷处理（CCAT）木材生成的木炭分别燃烧时，水蒸气对颗粒物（PM）的影响。原位挥发物的燃烧仅产生空气动力学直径<1 µm的PM（即PM ₁），主要产生空气动力学直径<0.1 µm的PM（即PM _0.1）。水蒸气可通过减少碱金属铝酸盐的形成显着增强细颗粒的成核，凝结和冷凝，并减少氧化铝反应器管对Na和K的捕获，从而导致PM _0.1的收率和模态直径均增加。水蒸气还可以增强焦炭的碎片，从而在焦炭燃烧期间提高空气动力学直径在1至10 µm之间的PM的产量（即PM _{1 – 10}）。对于痕量元素，在原位挥发物燃烧期间，挥发性元素（As，Cr，Ni，Cu和Pb）仅存在于PM _1中，水蒸气改变粒径分布（PSD），但对这些痕量的收率影响很小元素。在焦炭燃烧，砷，铬，铜和Ni同时存在于PM ₁和PM _{1 - 10}，而非易失性的Mn和Ti仅在PM本_{1 - 10}。由于增强的炭裂化，增加水蒸气含量可提高PM _1-10中As，Cr，Cu，Ni，Mn和Ti的产率。在炭燃烧过程中，水蒸气还局部产生较少的氧化条件以增强As的释放，促进气态氧化羟基氧化铬的生成并占据NiCl ₂（g）的产生，从而导致As和Cr的产率增加，而PM中的Ni产率降低_0.1。