低阶煤因储量丰富、附加价值高等特性逐步成为国家能源战略的关注点。近年来低阶煤的开采需求迅速增加，导致开采过程中产生的大量煤尘对矿工健康及井下安全生产造成了巨大隐患，对低阶煤煤尘的防治工作迫在眉睫。喷洒润湿型抑尘剂是一种简单且行之有效的抑尘方法，筛选适合的抑尘剂是实现高效抑尘的关键。然而，由于针对低阶煤煤尘专属抑尘剂的研发较少，目前尚无成熟高效的抑尘剂。因此，开发高效、经济、环保的低阶煤用抑尘剂具有重要的现实意义。

本论文以陕北神南矿区低阶烟煤为主要研究对象，选择四种不同类型的表面活性剂（阴离子型表面活性剂，阳离子型表面活性剂，非离子型表面活性剂，两性离子型表面活性剂）作为原料，以溶液表面张力、煤尘沉降时间为润湿特性的评价指标，优选出二元复配抑尘剂的单体。采用正规溶液理论计算和表面张力测定相结合的方法，复配出在表面张力降低的效能方面具有协同效应的二元体系，以润湿速率作为评价指标，考察其对煤尘润湿性的增效作用并探究润湿机理。进一步以无患子（Sapindus mukorossi Gaertn）作为原料，采用不同提取工艺提取皂苷，并将其与化学表面活性剂复配制取具有协同效应的生物-化学型三元复配抑尘剂，测定其润湿速率，分析其对煤尘润湿性的影响并探究其抑尘机理。通过模拟喷淋动态实验，测试其抑尘效果并评价抑尘性能，研究三元复配抑尘剂对低阶煤尘的抑尘机理。

实验结果表明：（1）选取的4种不同类型表面活性剂单体均可改善煤尘润湿性，且表面张力越低润湿速率越快。其中，非离子型表面活性剂烷基糖苷（APG）效果最佳，对煤尘润湿速率为0.42 g/min，在煤尘表面形成的单层吸附有利于改善煤尘润湿性。（2）APG单体与其他类型表面活性剂复配的二元体系中，以APG和磺琥珀酸二辛酯钠盐（AOT）为单体的非离子-阴离子二元复配体系，以不同单体质量比复配时，均在表面张力降低的效能方面具有协同作用，当APG与AOT质量比为2:3时（浓度为0.1 wt%），二元复配抑尘剂的表面张力与两种复配单体的表面张力相比分别下降了15.45%和10.21%。正规溶液理论计算结果表明，AOT与APG在混合胶束和吸附层中存在强相互作用，当体系中APG质量占比为0.37时，协同效应最显著，当总浓度为0.1 wt%时，二元复配抑尘剂的润湿速率为1.0 g/min，分别是APG和AOT单体润湿速率的2.4倍和4.3倍。（3）以无患子作为原料，采用超声辅助法提取皂苷，最佳提取工艺为乙醇体积分数60%，料液比1:7，提取温度50℃，提取时间1 h，无患子提取皂苷的得率为21.56%。（4）以皂苷及AOT作为复配单体制取的二元复配抑尘剂在表面张力降低的效能方面与单体相比有强协同效应，当体系中皂苷质量占比为0.52时，协同效应最强。该二元复配抑尘剂在总浓度为0.1 wt%时，润湿速率为0.72 g/min，是两种单体润湿速率的3倍以上。（5）向皂苷二元抑尘剂中加入APG制取三元复配抑尘剂，当APG、无患子皂苷、AOT按照质量比3:1:1复配时，煤尘沉降速率最快，当总浓度为0.1 wt%时，无患子皂苷三元复配抑尘剂的润湿速率可达6.67 g/min，是同浓度下APG、AOT、APG-AOT二元复配抑尘剂和皂苷二元复配抑尘剂的29倍、15.8倍、6.7倍及8.5倍。（6）与水相比，喷洒无患子皂苷三元复配抑尘剂对煤尘的抑尘效率可提高54.46% ~ 62.22%。

Low-rank coal has gradually become the focus of Chinese energy strategy due to its rich reserves and high added value. In recent years, the mining demand of low-rank coal is growing rapidly, resulting in a large amount of dust generated in the mining process, which has caused a huge hidden danger to miners’ health and safety production underground. Spraying wetting agent is a simple and effective dust suppression method, and screening suitable dust suppressant is the key to achieve high dust suppression efficiency. However, due to the lack of research and development of special dust suppressant for low-rank coal dust, there is no mature and efficient dust suppressant at present. Therefore, it is of great practical significance to develop efficient, economical, and environmentally friendly dust suppressants for low-rank coal dust.

Low-rank bituminous coal from Northern Shaanxi Shennan mining area was taken as the main research object, four different types of surfactants (anionic surfactant, cationic surfactant, non-ionic surfactant, zwitterionic surfactant) were selected to study their wetting characteristics as suppressant monomer by measuring the surface tension of solution and coal dust settling time. The binary compound system with synergistic effect in reducing the surface tension was screened by solution theoretical calculation and surface tension measurement. The synergistic effect on coal dust wetting was verified by the measurement of suppressant wetting rate. Furthermore, Sapindus mukorossi was selected as a raw material of biomass surfactant, saponins were extracted by different processes, and mixed with chemical surfactant to prepare ternary composite suppressant. Dynamic spray experiment was conducted to test the dust suppression efficiency of Sapindus saponin based suppressant and its dust suppression performance was evaluated and its dust suppression mechanism was explored.

The results show that: (1) the four kinds of surfactants all can improve the wettability of coal dust, and the lower surface tension of critical micelle concentration is, the faster the wetting rate is. Among them, Alkyl polyglycoside (APG) has the best wetting performance on coal dust, and its wetting rate was 0.42 g/min. it formed a monolayer adsorption on the surface of coal dust, which is conducive to improving the coal dust wettability. (2) In the binary system of APG and other surfactants, when the mass ratio of APG to Sodium di (2-ethylhexyl) sulfosuccinate (AOT) is 2:3 (the concentration is 0.1 wt%), this nonionic-anionic binary system shows a synergistic effect on reducing the surface tension, which is of 15.45% and 10.21% decrease to the two monomers. The results of solution theoretical calculation show that there are strong interactions between AOT and APG in the mixed micelles and interfacial adsorption layer. When the mass fraction of APG is 0.37, the synergistic effect is the most significant, and when the concentration is 0.1 wt%, the wetting rate of the composite surpressant is 1.0 g/min, which is 2.4 times and 4.3 times of that of APG and AOT monomer, respectively. (3) Sapindus mukorossi was used as raw material and ultrasonic assisted extraction method was used to extract saponins. The optimum extraction conditions were as follows: 60 percent of ethanol, solid-liquid ratio 1:7, extraction temperature 50℃, extraction time 1 h. The yield of Sapindus mukorossi saponins was 21.56%. (4) When saponin and AOT were compounded, the binary compound system had a strong synergistic effect on reducing surface tension compared with monomer, and the synergistic effect was the strongest when the mass ratio of saponin was 0.52. The wetting rate of coal dust is 0.72 g/min at the concentration of the binary compound solution of 0.1 wt%, which is more than three times of that of the two monomers. (5) When the mass ratio of APG, Sapindus saponin and AOT is 3:1:1, the wetting rate of the ternary composite suppressant is the fastest. The wetting rate of the suppressant was 6.67 g/min at the concentration of 0.1 wt%, which is 29 times, 15.8 times, 6.7 times and 8.5 times of APG, AOT, APG-AOT compound and saponin-AOT compound at the same concentration. (6) Compared with water, the dust suppression rate of inhalable coal dust can be increased by 54.46% ~ 62.22% by spraying Sapindus saponin ternary compound dust suppressant.