摘要
煤气化细渣是一种资源化利用率较低的固体废弃物,其残炭与灰质的相互混杂制约了针对其中残炭或无机矿物质(灰质)利用的2个方面,残炭与灰质分离是气化渣高效资源化利用的前提。重力分选对于气化渣中+0.125 mm较粗粒级分选效果较好,但气化细渣0~0.074 mm粒级含量高,常规泡沫浮选细粒级药剂消耗量大,泡沫残炭产品中细粒灰质夹带严重,多段分选工艺复杂,泡沫残炭产品水分较高。疏水-亲水双液分离(HHS)是集分离与脱水为一体的技术,采用HHS技术对宁夏煤业公司的气化细渣的残炭与灰质分离进行了试验研究,考查了搅拌速度、搅拌时间、疏水液体用量对煤气化细渣炭、灰分离效果的影响规律。结果表明,随搅拌速度增加残炭产品灰分由66.35%降低至20.80%,尾矿灰分由79.70%提高至98.25%,炭、灰分离效果明显变好;随着搅拌时间增加,残炭产品灰分由33.96%降低至28.96%,对于炭、灰分离效果影响较小;随疏水液体用量增加残炭产品灰分由28.98%降低至24.31%,再升高到26.09%,HHS中疏水液体为样品质量的60%时最佳。HHS相比泡沫浮选可得到更好的炭、灰分离效果,残炭产品灰分在30%以下,灰质产品灰分在95%以上。通过SEM-EDS、工业分析、元素分析、XRF分析和BET孔结构分析,得到从原样到HHS精矿与尾矿的表面形貌变化、元素组成富集情况、孔结构变化趋势,为气化细渣炭、灰分离后的分质利用提供了依据。通过残炭与灰质表面性质的测定,利用Zeta电位分析、接触角分析、XPS分析以及扩展DLVO理论计算分析了煤气化细渣疏水-亲水双液炭、灰分离机理,为后续强化炭、灰分离机制提供了理论依据。Zeta电位分析表明残炭与正庚烷油珠的黏附性更强,炭经正庚烷处理后C—C/C—H官能团的含量增加了3.61%,接触角由36.11°增加到76.13°,使炭表面疏水性显著增强;而灰经正庚烷处理后接触角由28.0
The coal gasification fine slag is a kind of solid waste that is poorly utilized.The mixing of residual carbon and ash material restricted the utilization of both the residual carbon and the inorganic minerals,or ash material.The separation of carbon and ash is the premise of efficient resource utilization of the gasification slag.Gravity separation shows satisfactory separation effect on the coarse slags of+0.125 mm.In the case of the more abundant fine slags of-0.074 mm,flotation is more frequently used but consumes large quantity of reagents and the ash material are readily entrapped in the froth product of carbon.Moreover,multi-stage is necessary which makes the flowsheet much complicated and the moisture content of the residual carbon product is also high.Hydrophobic-hydrophilic separation(HHS)is a technology integrating separation and dehydration.In this paper,HHS technology was used to separate the residual carbon and the ash material from the coal gasification fine slags produced in Ningxia Coal Industry Company,and the effect of mixing speed,mixing time and amount of hydrophobic liquid on the separation was investigated.The experiment results show that with the increase of mixing speed,the ash content of residual carbon products decreases from 66.35%to 20.80%,the ash content of tailings increases from 79.70%to 98.25%,indicating a significantly increased separation effect.With the increase of mixing time,the ash content of residual carbon products decreased from 33.96%to 28.96%,indicating a slight influence of the mixing time on the separation.With the increase of the amount of hydrophobic liquid,the ash content of residue carbon product decreases from 28.98%to 24.31%and then increases to 26.09%,indicating The hydrophobic liquid in HHS is best at 60%of the sample quality.Compared with froth flotation,HHS can give better separation effect for the carbon and the ash in the gasification slags,with the ash content of the residual carbon products and the ash product below 30%and above 95%,respectively.Employin
作者
薛中华
董连平
刘安
樊民强
杨崇义
王建成
鲍卫仁
樊盼盼
XUE Zhonghua;DONG Lianping;LIU An;FAN Minqiang;YANG Chongyi;WANG Jiancheng;BAO Weireng;FAN Panpan(College of Mining Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Key Laboratory of Coal Science and Technology,Shanxi Province and Ministry of Education,Taiyuan 030024,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2022年第6期2472-2482,共11页
Journal of China Coal Society
基金
国家重点研发计划资助项目(2019YFC1904302)
省部共建煤炭高效利用与绿色化工国家重点实验室开放课题资助项目(2021-K81)
国家能源集团煤制油研究院技术课题资助项目([2020]010)。
关键词
煤气化细渣
疏水液体
团聚
疏水-亲水分选
扩展DLVO理论
coal gasification fine slag
hydrophobic liquid
agglomeration
hydrophobic-hydrophilic separation
EDLVO theory
