ABSTRACT

A cascading sequence of two full-scale REFLUX™ Classifiers was tested using 1.0 mm top size coal. The gravity separation in the first stage gave a clean coal product down to about 0.03 mm. The second stage then deslimed this product with minimal coal loss. At volumetric feed rates up to roughly 100 m³/h (~ 50 t/h solids), 30–50 wt.% ash feeds were reliably cleaned to give product ash values less than 10 wt.% at overall combustible recoveries of 60–80 %. At higher feed rates up to 240 m³/h (~ 100 t/h solids), product ash values were in the range 8–13 wt.% at 43–67% combustible recovery. One run processed 150 m³/h of a very problematic high-slimes feed with 35 wt.% -0.038 mm slimes and 52 wt.% head ash, giving a 14 wt.% ash product at 56% combustible recovery. The deslime unit size partition Ep values increased exponentially with overflow rate, but remained less than 0.05 mm for overflow rates up to 100 m³/h. The cut point size increased with the deslime unit overflow flux. When the effects of cut point density and hindered settling were accounted for, there was good agreement with previous laboratory and pilot-scale test work.

摘要

使用 1.0 mm 顶部尺寸的煤测试了两个全尺寸 REFLUX™ 分级器的级联序列。第一阶段的重力分离使精煤产品下降到约 0.03 毫米。然后第二阶段以最小的煤损失对该产品进行脱泥。在高达大约 100 m ³ /h（约 50 t/h 固体）的体积进料速率下，30-50 wt.% 的灰进料被可靠地清洗，以使产品灰分值小于 10 wt.%，总可燃回收率为 60- 80%。在高达 240 m ³ /h（约 100 t/h 固体）的较高进料速率下，产品灰分值在 8-13 wt.% 范围内，可燃物回收率为 43-67%。一次处理 150 m ³/h 具有 35 wt.% -0.038 mm 煤泥和 52 wt.% 头灰的非常有问题的高煤泥进料，在 56% 的可燃回收率下得到 14 wt.% 的灰产品。脱粘液单位尺寸分区Ep值随溢流率呈指数增长，但对于高达 100 m ³ /h的溢流率仍保持小于 0.05 mm 。切割点尺寸随着脱泥单元溢出通量的增加而增加。当考虑到切割点密度和受阻沉降的影响时，与以前的实验室和中试工作有很好的一致性。