焦化废水中主要污染物对煤可浮性的影响及机理分析  

Effect of major pollutants on flotability of coal in coking wastewater and its mechanism analysis

作　　者：蔡昌凤[1] 郑西强[1] 唐传罡[1] 高琴[1] 

机构地区：[1]安徽工程大学生物与化学工程学院,安徽芜湖241000

出　　处：《煤炭学报》2010年第6期1002-1008,共7页Journal of China Coal Society

基　　金：安徽省自然科学基金重点资助项目(08040102002)

摘　　要：开发利用洗煤厂洗水闭路循环系统实现焦化废水大循环零排放新工艺,需考察焦化中水对浮选有无不良影响。单元浮选试验表明:随着洗水中污染物浓度提高,浮选精煤灰分和产率均升高,通过调整药剂制度,能保证浮选精灰分合格,但产率下降;用焦化中水洗煤,污染物浓度低于污水综合排放标准二级限值时,对煤泥浮选的影响可忽略。用油水润湿速度比(ROH)、Zeta电位、红外光谱表征研究煤粉吸附焦化中水主要污染物氨氮、苯酚、喹啉和微生物后,煤表面电性、表面疏水性、可浮性变化趋势,揭示其污染机理。污染物吸附改变了煤浆的Zeta电位,变化显著:未吸附时Zeta电位为-17.27mV,吸附后依次为吸附硝化菌-21.88～-26.62mV、喹啉-25.21～-29.47mV、苯酚-27.39～-32.58mV、氨氮-32.13～-38.53mV、反硝化菌-38.80～-43.40mV。煤吸附疏水性硝化菌及喹啉,煤表面疏水性提高;氨氮、苯酚在吸附量分别达到一定量后,对煤表面疏水性的负面影响显现;亲水性反硝化菌吸附使煤表面疏水性明显变差。红外光谱分析表明,污染物对煤粉表面疏水性的影响主要取决于吸附质本身所表现的亲、疏水性官能团。Exploiting and using the closed-circuit system of wash water in coal washery to achieve major cycle zero draining new process of coking wastewater,it’s necessary to investigate whether wastewater in coking has adverse effects on flotation.Cell flotation tests show that when pollutant concentration in coal washing water is high,the flotation coal ash and yield increase at the same time,the flotation of fine ash can guarantee compliance by adjusting the pharmaceutical system,but the production rate droppeds.Washing coal by using water in coking,the impact of coal flotation can be neglected when pollutant concentrations below the class Ⅱ of the national wastewater discharge standard.Hydrophobic variation tendency in the coal surface,surface potential and flotability were investigated by using wetting speed of oil and water （ROH）,Zeta potentialand and infrared spectrum after pulverized coal adsorbed main contamination such as ammonian,phenol,quinoline,and microbe,and the mechanism of pollution was revealed：Zeta potential have a significant change of coal-water system after adsorption of pollutants,Zeta potential is-17.27 mV without adsorption,after adsorption of pollutants and micro-organisms,Zeta potential are-21.88～-26.62 mV （nitrobacteria）,-25.21～-29.47 mV （quinoline）,-27.39～-32.58 mV （phenol）,-32.13～-38.53 mV （ammonian） and-38.80～-43.40 mV （denitrifying bacteria）.The surface hydrophobicity of coal increases by adsorbing nitrifying bacteria and quinoline in surface.When coal adsorbed the amount of ammonian,phenol over a certain adsorption respectively,the negative impact of coal surface hydrophobicity is revealed relatively.While coal adsorbed denitrifying bacterium,its surface hydrophobicity deteriorates obviously.Infrared spectroscopy characterization analysis indicates that the effect of pollutants on the surface of hydrophobic mainly restes with the performance including hydrophilicity,hydrophobicity of the material itself.

关 键 词：焦化废水 可浮性 疏水性 吸附 

分 类 号：X784[环境科学与工程—环境工程]