Study On The Compound And Application Of Additive For Coal Water Slurry

The low rank coal of Shenhua was studied in this paper. The performance of commercially available additives of coal water slurry (CWS) and industrial applied additives in the preparation of Shenhua CWS was investigated. Based on the additive of naphthalene series (GN), the influence of anionic additive, nonionic additive, additive of gender and salt compound with GN was studied. For different rank of coal, compound additive was used in the preparation of CWS, the adaptability of compound additive was studied; The mechanism of compound additive was analysis by pore characteristics, dehydration rate, spreading area and morphology.Commercially available additives and additives can be prepared with good rheological properties and stability of CWS, but the concentration was only59%.Based on additive of naphthalene, GN and salt dispersion of ST was compounded at the ratio of85:15, in addition to0.3%, Shenhua coal slurry concentration can be effectively improved to62%. The effect of ternary compound was not obvious.The results showed that the concentration of different rank coals’CWS prepared by the compound additive is1%to3%higher the prepared by GN. The compound additive coal adaptability is wide. The influence of surface functional groups of coal on the concentration of CWS was the Aromatic ring, Methyl (Methylene)>Hydroxyl> Ether bond. Among them, Methyl (Methylene) and Ether bond to the concentration was positively correlated, the Aromatic ring and Hydroxyl were negatively correlated; Oxygen to carbon ratio of coal was negative index related to the concentration of the CWS; The influence of surface functional groups and oxygen to carbon ratio on the concentration of CWS was smaller than GN additive when GT additive applied to different coal.Wetting and dispersing of GT is better than GN. The surface morphology of the slurry prepared by GT flow better, more smooth. Slurry unit mass spreading area is up to1300mm2/g. Because of the excellent adsorption properties of complex additive GT, the water loss rate of the slurry prepared by GT was differ from the slurry prepared by GN. After drying the CWS prepared by GT and GN, the pore characteristics of coal particles are different. Compared with raw coal, GT additive greater than additive GN in reducing the coal particle surface area and total pore volume. The outstanding performance of the compound additive GT in the wetting and dispersing and adsorption properties are the main factors to the preparation of high concentration of CWS.