Effect of chemical properties of particle surface on the viscosity and cohesion behavior of coal slurry fuel(CSF).

1.目的采用煤浆燃料模型，研究颗粒表面化学性质对粘度和凝聚力的影响。结果和讨论(1)利用石墨-粘土矿物固相的模型-COM(煤油混合物)。模型由石墨作为碳质材料，粘土矿物(二氧化硅、氧化铝、高岭土和蒙脱石)作为灰分，液体石蜡作为液体介质组成。模型COM的粘度随白炭黑和高岭土加入量的增加而增加，随蒙脱土加入量的增加而逐渐降低。粘聚力按加入材料的顺序依次增加：氧化铝、蒙脱石、高岭土、二氧化硅。粘土矿物具有较大的吸油性，往往会产生较大的粘度和凝聚力。(2)利用包裹有有机羧酸的碳酸钙颗粒，使碳酸钙颗粒与脂肪酸和芳香族羧酸发生反应。表面的化学性质和亲水亲油平衡随着化学物种和有机酸含量的变化而变化。因此，具有不同化学性质的颗粒具有相同的颗粒尺寸、相同的颗粒尺寸分布和相同的颗粒形状。结果表明，颗粒与液体石蜡或水制备的COM和CWM的粘度和凝聚力受颗粒表面化学性质的不同影响较大，而CSF具有相同的孔隙率。通过测定所用颗粒的液体吸收率，可以估算其粘度和粘聚力。

1. Objective By using model-CSF(coal slurry fuel), effect of chemical properties of particle surface on viscosity and cohesion behavior was investigated.2. Results and Discussion (1) Model-COM(coal oil mixture) by use of graphite-clay mineral solid phase. Model-COM consisted of graphite as a carbonaceous material, clay minerals(silica, alumina, kaoline and montmorillonite) as ashes, and liquid paraffin as liquid phase medium. The viscosity of the model-COM increased with increasing amount of silica and kaoline added, whereas its viscosity decreased gradually with increasing amount of montmorillonite added. The cohesion was increased in the order of materials added: alumina< montmorillonite < kaoline < silica. The clay minerals being capable of large oil-absorption tended to cause large viscosity and cohesion.(2) Model-CSF by use of calcium carbonate particle coated with organic carboxylic acids.Calcium carbonate particles were reacted with fatty acids and aromatic carboxylic acids. The chemical properties and hydrophile-lipophile balance on the surface was varied by means of changes both in the chemical species and in the amount of organic acids. Thus, the particles having different chemical properties and having the same particle size, the same size distribution, and the same particle shape. The viscosity and cohesion behavior of COM and CWM prepared with the particles and liquid paraffin or water, respectively, were found to be greatly influenced by difference in the chemical properties of the particle surface, nevertheless the CSF having the same porosity. The viscosity and cohesion behavior were found to be estimated by determining the liquid absorption of the particles used.