准格尔煤燃烧后灰渣中氧化铝含量高,采用循环流化床燃烧准格尔煤水煤浆可进一步提高灰渣中氧化铝的提取效率和氧化铝活性,具有极高的技术潜力。采用三因素六水平正交实验法研究了粗粒级和超细粒级煤粉质量比、细粒级煤粉质量分数及分散剂亚甲基双萘磺酸钠(NNO)添加量对准格尔煤水煤浆定浓黏度(浆体浓度60%)的影响,对比分析了不同制浆方案下浆体的最大成浆浓度(浆体表观黏度为1200mPa·s)、流动性、稳定性和流变特性。结果表明,影响准格尔煤水煤浆定浓黏度的因素由主到次依次为粗粒级和超细粒级煤粉质量比、分散剂NNO添加量、细粒级煤粉质量分数;正交实验得到的最佳工艺条件为,粗粒级和超细粒级煤粉质量比4∶1、细粒级煤粉质量分数40%、NNO添加量0.35%,此时浆体的定浓黏度为479mPa·s,最大成浆浓度为63.5%,流动性为12.3cm,稳定性为15d;三峰级配方式下,准格尔煤水煤浆可获得更好的浆体性能,其最大成浆浓度相较于双峰级配方式提升超过了2%,是更适用于制备准格尔煤水煤浆的级配方式。

The ash slag from Jungar coal possesses high utilization value due to its sub-stantial content of aluminum oxide. Meanwhile, the combustion of Jungar coal-water slurry in circulating fluidized bed can significantly boost the extraction efficiency and activity of alumina, making it a method with remarkable technical potential. In this paper, the influences of the mass ratio of coarse to ultra-fine pulverized coal, the mass fraction of fine pulverized coal, and the amount of NNO dispersant on the constant concentration viscosity (slurry concentration was 60%) of Jungar coal-water slurry were studied using the three-factor six-level orthogonal experi-mental method. Besides, the maximum slurry concentration (slurry apparent viscosity was 1 200 mPa·s), fluidity, stability and rheological properties of the slurry under different slurry prepa-ration schemes were compared and analyzed in detail. The results indicate that the factors affect-ing the constant viscosity of Jungar coal-water slurry, ranked by their impact magnitude, are the mass ratio of coarse to ultra-fine pulverized coal, the amount of NNO dispersant, and the mass fraction of fine pulverized coal, respectively. Moreover, the optimal technological conditions de-rived from the orthogonal experiment are as follows: a mass ratio of coarse to ultra-fine pulver-ized coal of 4∶1, a mass fraction of fine pulverized coal of 40%, and an NNO dispersant addition of 0.35%. Under these conditions, the constant concentration viscosity of the slurry is 479 mPa·s, the maximum slurry concentration is 63.5%, the fluidity is 12.3 cm, and the stability is 15 d. In addition, the adoption of the three-peak grading method yields enhanced slurry per-formance, with an increase in maximum slurry concentration of over 2% compared to the double-peak grading method. Therefore, the three-peak grading method is more suitable for the prepara-tion of Jungar coal-water slurry.