Study On Experimentation Of The High Suspended Solids Concentration Coal Slurry Water Treatment

The Sima coal firm is a large scale coal selecting firm which produces 2.0Mt every year was designed by the designing institute of Taiyuan Coal Industry and was built and put into production in October 2005. In the actual production process, because of the high concentration and be mired easily, it is difficult to achieve the purpose of the solid-liquid separation by natural precipitation which makes the fine grain coal slurry gather unceasingly in the craft system and has affected the enterprise's regular production seriously and fails to achieve the requirement of the washing water closed circuit and washing with clean water of the coal slurry water system in the coal efficiency win-win. In order to solve the problem of the high concentration of coal slurry water technically, the discussion and investigation on technical parameter and technical process appears extremely essential.This article is in view of the characteristic of high concentration of the coal slurry water of Sima coal firm, With the purpose of the turbidity of wastewater under 100 NTU,the emphasis researches are the choice of best flocculation medicament and the ideal water power condition in the process of the coal slurry water, the determination on the dosage of flocculation and the key influent factor in the process of the coal slurry water. In the experiment, we use FeCl3, MgSO4,Al2(SO4)3, PAC and PAM with different molecular weight. The research indicated that because of its characteristic of high concentration, selecting polyacrylamide NPAM-7080 as the processing medicament is not only economical,but also has large velocity in the processing of muddy-liquid sinking and low turbidity of water leakage. It can make good processing effects and achieve the purpose of washing water closed circuit completely.The simultaneous research indicated that: for the coal slurry water of the Sima coal firm the dosage of NPAM-7080 is 80~100g/tï¹’ coal, the best waterpower condition is:G 200-300S-1, T 10-15S and GT 2000~3000. If we add NPAM-7080 step by step, the best ratio is 6:4(For the first time, 60 percent is added and for the second time 40 percent is added). This method can save the medicament by approximately 15%. If we throw inorganic coagulating agent together with the organic flocculant, the dosage of the organic flocculant can be reduced. For the coal slurry water of the Sima coal firm, the best dosage of inorganic coagulating is about 0.6kg/tï¹’coal with the best dosage of organic flocculant is 40~60g/tï¹’coal. Through economical calculation, the cost of treatment with only NPAM-7080 is $0.09~0.11 /m3and the cost of treatment with NPAM-7080 and PAC is $0.11~0.13/m3. From the data, the first method is recommended.Based on the experiment, according to the coal slurry water samples under the best water power condition can satisfy the water turbidity and the muddy-liquid level sinking, we establish mathematical model on the relation between density and medication quantity: Y=0.0723X-1.825, the square of R2=0.9081.