煤泥选择性絮凝特性研究

发布时间：2018-02-04 03:50

本文关键词： 煤泥高岭石分散絮凝　出处：《华北理工大学》2016年硕士论文　论文类型：学位论文

【摘要】：为了改善浮选处理极细粒级煤泥灰分高产率低的缺点,以内蒙某地烟煤作为代表性煤种,对极细粒级煤泥进行了选择性絮凝试验研究。首先对纯煤和高岭石纯矿物进行了分散与絮凝条件试验,筛选出分散剂与絮凝剂及其试验条件,然后在此基础上对人工混合矿进行了分散絮凝条件试验。最后,通过动电位测定和红外光谱分析对煤和高岭石的絮凝作用机理进行了分析。四种分散剂进行条件试验,得出当矿浆浓度为20g/l,柠檬酸用量为24mg/l,硅酸钠用量为20mg/l,多聚磷酸钠用量为16mg/l,六偏磷酸钠用量为20mg/l时,各药剂均在p H值为6时两矿物的分散效果差别最大,即选择性分散。将四种药剂的最佳条件进行对比,四种药剂对高岭石的分散效果为柠檬酸六偏磷酸钠多聚磷酸钠硅酸钠,对煤的分散效果为六偏磷酸钠多聚磷酸钠硅酸钠柠檬酸,结合各药剂对两矿物的分散效果最终确定柠檬酸为分散剂。对四种絮凝剂进行条件试验,结果得出糊精用量为20mg/l,聚合氯化钙用量为110mg/l,聚合氯化铝铁用量为110mg/l,硫酸铝钾用量为20mg/l,均在p H值为6时,煤与高岭石的选择性絮絮凝效果较好。最后将各个药剂的结果进行比较,得出硫酸铝钾作为选择性絮凝剂效果较好。在最佳的分散、絮凝条件下对人工混合矿(灰分为35%)进行分选,试验表明,当矿浆浓度为35g/l时,柠檬酸用量为20mg/l,硫酸铝钾用量为140mg/l时,在p H值为6时,可获得底流灰分为14.3%,回收率为59.65%的精煤,选择性絮凝较好。通过红外光谱分析得出加入药剂前后,高岭石谱图基本没有变化,高岭石与硫酸铝钾为物理吸附。而煤在3580cm-1处出现了新的吸收峰,该处可能是羟基的吸收峰,其它吸收峰在原有位置处左右移动,煤与硫酸铝钾的吸附为化学吸附。通过动电位检测得出加入药剂后高岭石和煤电位绝对值逐渐降低,只有在p H值为6时,高岭石Zeta电位绝对值变化较小,煤相对变化大,可能与药剂发生了电荷吸附。
[Abstract]:In order to improve the disadvantage of high yield and low yield of very fine grained coal slime treated by flotation, the bituminous coal in Inner Mongolia is regarded as the representative coal. The selective flocculation test of very fine coal slime was carried out. Firstly, the dispersion and flocculation conditions of pure coal and kaolinite were tested, and the dispersant and flocculant and their experimental conditions were screened out. On the basis of this, the conditions of dispersion flocculation of artificial mixed ore were tested. Finally. The flocculation mechanism of coal and kaolinite was analyzed by potentiodynamic measurement and infrared spectrum analysis. Four dispersants were tested under conditions, and the results showed that the slurry concentration was 20g / l. When the amount of citric acid is 24 mg / l, sodium silicate is 20 mg / l, sodium polyphosphate is 16 mg / L, sodium hexametaphosphate is 20 mg / l. The dispersing effect of the two minerals was most different when pH value was 6:00, that is, selective dispersion. The optimum conditions of the four chemicals were compared. The dispersing effect of four kinds of medicament to kaolinite is sodium citrate sodium hexametaphosphate sodium polyphosphate sodium silicate and sodium hexametaphosphate sodium polyphosphate sodium silicate sodium citric acid. Combined with the dispersing effect of the two minerals, citric acid was determined as dispersant. The results showed that the dosage of dextrin was 20 mg / l under the conditions of four flocculants. The dosage of polycalcium chloride is 110 mg / l, the amount of polyaluminium and ferric chloride is 110 mg / l, the amount of potassium aluminum sulfate is 20 mg / l, and the pH is 6:00. The effect of selective flocculation of coal and kaolinite is better. Finally, the results of each medicament are compared, and it is concluded that the effect of aluminum sulfate as selective flocculant is better than that of kaolinite. The artificial mixed ore (ash is divided into 35 parts) is sorted under flocculation condition. The experiment shows that the dosage of citric acid is 20mg / l when the pulp concentration is 35g / l. When the amount of aluminum potassium sulfate is 140 mg / l, and the pH value is 6:00, the bottom ash can be divided into 14. 3% and the recovery rate is 59.65%. Selective flocculation is better. Infrared spectrum analysis shows that the kaolinite spectrum is basically unchanged before and after the addition of the agent. Kaolinite and potassium aluminate sulfate are physically adsorbed, while new absorption peaks appear in coal at 3580 cm ~ (-1), which may be the absorption peaks of hydroxyl groups, and the other absorption peaks move around the original position. The adsorption of coal with potassium aluminum sulfate is chemisorption, and the absolute value of kaolinite and coal potential decreases gradually after the addition of medicament, only when pH is 6:00. The absolute value of Zeta potential of kaolinite is relatively small, and the coal has a great change, which may result in charge adsorption with the reagent.
【学位授予单位】：华北理工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TD94

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