等离子体氧低温灰化仪的试制及应用

A HOME-MADE PLASMA OXIDIZER FOR LOW TEMPERATURE ASHING AND ITS APPLICATION IN OIL SHALE CHEMICAL ANALYSIS

根据低温等离子体氧氧化的基本原理及文献资料,自行设计研制了一套能用于固体燃料低温灰化的等离子体氧低温灰化仪。实验结果表明,仪器的性能良好。在氧流速为 50mL/min,真空度小于 0.26kPa,高频发生器输出50W时,该仪器可对煤或油页岩试样进行正常的低温灰化。灰化时间与灰化后的残留有机碳达到国外同类仪器工作的水平。对仪器的氧化反应器与真空系统的接口作了新的设计,使气体中残余的等离子体氧充分复合为分子态,保证了仪器的长期安全操作。该仪器可用于测定煤和油页岩矿物质的含量;还可用于直接测定油页岩中有机质的氢碳比。

Based on the principle of plasma oxidation for low temperature ashing of coal and published technical information, a plasma oxidizer has been trial-manufactured with domestic assemblies. The optimum operation parameters for low temperature ashing of coals or oil shales are given. A novel design for the junciton between oxidizing reactor and vacuum system improves the reliability and safety of the vacuum parts. The overall performance of this home-made apparatus is comparable to the imported instruments. However, it costs only less than 5% of the price of the latter. By using this apparatus, the mineral content and hydrogen carbon ratio of oil shales were determined directly. The results agree well with the measurements assessed from the samples of kerogen concentrates, prepared after the removal of minerals by HCl and HF treatments. The relative high nitrogen content (0.24%, Dumas) of the LTA residue from Fushun oil shale implies the existance of N-contai-ning minerals, ammonium silicates, such as buddingtonite, has been verified by examination of the LTA residue with X-ray diffraction spect roscopy.