Division of Combustion Physics , Lund University , P.O. Box 118, SE-221 00 , Lund , Sweden.
R&D, Strategic Development , Vattenfall AB , 814 26 Älvkarleby , Sweden.
Anal Chem. 2019 Apr 2;91(7):4719-4726. doi: 10.1021/acs.analchem.9b00203. Epub 2019 Mar 18.
An understanding of potassium chemistry in energy conversion processes supports the development of complex biomass utilization with high efficiency and low pollutant emissions. Potassium exists mainly as potassium hydroxide (KOH), potassium chloride (KCl), and atomic potassium (K) in combustion and related thermochemical processes. We report, for the first time, the measurement of the ultraviolet (UV) absorption cross sections of KOH and KCl at temperatures between 1300 K and 1800 K, using a newly developed method. Using the spectrally resolved UV absorption cross sections, the concentrations of KOH and KCl were measured simultaneously. In addition, we measured the concentrations of atomic K using tunable diode laser absorption spectroscopy, both at 404.4 and 769.9 nm. The 404.4 nm line was utilized to expand the measurement dynamic range to higher concentrations. A constant amount of KCl was seeded into premixed CH/air flames with equivalence ratios varied from 0.67 to 1.32, and the concentrations of KOH, KCl, and atomic K in the hot flue gas were measured nonintrusively. The results indicate that these techniques can provide comprehensive data for quantitative understanding of the potassium chemistry in biomass combustion/gasification.
理解能量转换过程中的钾化学有助于高效低排放地开发复杂的生物质利用。在燃烧和相关热化学过程中，钾主要以氢氧化钾（KOH）、氯化钾（KCl）和原子钾（K）的形式存在。我们首次报道了使用新开发的方法在 1300 K 至 1800 K 温度范围内测量 KOH 和 KCl 的紫外（UV）吸收截面。利用光谱分辨的 UV 吸收截面，我们同时测量了 KOH 和 KCl 的浓度。此外，我们使用可调谐二极管激光吸收光谱法，在 404.4nm 和 769.9nm 处测量了原子 K 的浓度。404.4nm 线用于将测量动态范围扩展到更高的浓度。将一定量的 KCl 注入当量比为 0.67 至 1.32 的预混 CH/空气火焰中，非侵入性地测量热烟道气中的 KOH、KCl 和原子 K 的浓度。结果表明，这些技术可以为生物质燃烧/气化中钾化学的定量理解提供全面的数据。
