摘要
为提高电化学除油效果,通过形态原位识别技术分析电化学方法处理油田含聚合物污水的动态过程中油珠和气泡的聚集形态变化,利用絮体分形理论描述了油珠和气泡的分形成长特征,用分形维数表征了电化学处理时间对二者的影响及变化规律,研究了油珠和气泡变化对除油效果的影响。结果表明,气泡分时形态变化较小,其分形维数(D_f)在2.05附近波动;油珠分时形态变化较大,随着处理时间的延长油珠粒径变大,其D_f在1.804数1.964之间,二者的形态与分形维数呈现良好的相关性。输出电流越大,气泡的平均当量圆直径(d_e)越小,除油效果越好。在电化学处理过程中,油珠与气泡发生黏附,随着处理时间延长油珠在气泡的作用下快速聚集,加快了油珠的上浮分离,气泡d_e变小,油珠平均当量圆直径(d_n)变大。在处理电流为4 A、动态停留时间(t_2)为25min时,气泡de为49.72μm,油珠dn为57.39μm,除油率达到86.15%;电流为8 A时,t_2在10数20 min的除油率大于80%。较高输出电流、较短的动态停留时间或较低输出电流、较长的停留时间均有利于改善除油效果。图15参21
In order to improve the electrochemical degreasing effect,the morphological in-situ identification technology was used to analyze the aggregation morphology of oil beads and bubbles in the dynamic process of treating polymer-containing wastewater in oilfield. The flocculation theory was used to describe the formation of oil beads and bubbles. The influence of electrochemical treatment time on the two processes and their variation were characterized by fractal dimension,and the effect of oil beads and bubbles changes on degreasing effect was studied. The results showed that the change in time-sharing morphological of bubbles was small,and the fractal dimension(D_f)fluctuated around 2.05. The time-sharing morphological of oil beads changed greatly. With the increase of treatment time,the oil particle size became larger,and its D_f was 1.804—1.964,showing a good correlation between morphology and fractal dimension. The larger the output current,the smaller the average equivalent circle diameter(d_e)of the bubble and the better degreasing effect were. During the electrochemical treatment process,oil beads adhered to the bubbles,and the oil beads rapidly accumulated under the action of bubbles as the treatment time prolonged,which accelerated the floating separation of oil beads. As a result,the debecame smaller,and the average equivalent circle diameter of oil beads(d_n)became larger. When the treatment current was 4 A and the dynamic residence time(t_2)was 25 min,the dewas 49.72 μm,the dnwas 57.39μm,and the degreasing rate reached 86.15%. When the current was 8 A and t_2 was 10—20 min,the degreasing rate was above 80%.Higher output current and shorter dynamic residence time or lower output current and longer dynamic residence time were beneficial to improve degreasing.
引文
[1]LI Yu,MEI Han,FANG He.A review of treating oily wastewater[J].Arabian J Chem,2013,10(2):1913-1922.
[2]国丽萍,刘双.电破乳微观机理及其影响因素分析进展[J].油田化学,2018,35(4):750-756.
[3]王雨,林莉莉,斯绍雄,等.聚合物驱采油污水的水质深化处理技术[J].油田化学,2018,35(2):356-361.
[4]翟磊,靖波,王秀军,等.电化学脱稳技术处理油田含聚污水[J].化工环保,2016,36(3):243-249.
[5]尹先清,张健,靖波,等.聚驱污水含聚量对污水处理设备的影响[J].环境工程学报,2012,6(10):3499-3502.
[6]梁伟,赵修太,韩有祥,等.油田含聚污水处理与利用方法技术探讨[J].工业水处理,2010,30(10):1-5.
[7]张健.一种适于海上油田的含聚污水高效处理方法[J].油气田地面工程,2013,32(8):9-10.
[8]朱米家,田伟,刘瑞平,等.响应面法分析Fenton氧化处理采油废水的过程[J].环境工程学报,2016,10(3):1217-1222.
[9]武捷.电絮凝法处理乳化油废水的试验研究[D].镇江:江苏大学,2016:10-13.
[10]朱米家,尹先清,陈武,等.电-Fenton技术处理聚合物驱采油废水[J].工业用水与废水,2011,42(5):20-22.
[11]范欣.絮凝气浮中气泡分布与絮凝剂配伍性研究[D].青岛:中国石油大学,2010:12-14.
[12]黄璐.油滴/气泡尺度对模拟含油废水气浮效果的影响[D].上海:东华大学,2012:23-25.
[13]宋娟娟.水处理絮凝过程絮体分形成长特性研究[D].哈尔滨:哈尔滨工业大学,2009:18-20.
[14]BOWERS D G,MCKEE D,JAGO C F,et al.The area-to-mass ratio and fractal dimension of marine flocs[J].Estuarine,Coastal and Shelf Science,2017,189(2):224-234.
[15]范菲菲.水处理微絮凝阶段絮体形态特征对过滤效能影响研究[D].哈尔滨:哈尔滨工业大学,2012:10-14.
[16]KORBAHTI B K,ARTUT K.Electrochemical oil/water demulsification and purification of bilge water using Pt/Ir electrodes[J].Desalination,2010,258(1/3):219-228.
[17]SANTOS I D,DEZOTTI M,DUTRA A J B.Electrochemical treatment of effluents from petroleum industry using a Ti/RuO2anode[J].Chem Eng J,2013,226(1):293-299.
[18]ZHAO Xu,LI Angzhao,MAO Ran,et al.Electrochemical removal of haloacetic acids in a three-dimensional electrochemical reactor with Pd-GAC particles as fixed filler and Pd-modified carbon paper as cathode[J].Water Res,2014,51(1):134-143.
[19]曹伟丽,王彦龙,郭明,等.采油污水的电气浮处理技术研究[J].应用化工,2014,43(8):1547-1548.
[20]范荣桂,邓岚,朱东南.微污染矿井水中微絮体的形成及分形特征[J].环境工程学报,2013,7(1):214-220.
[21]李振亮,张代钧,卢培利,等.活性污泥絮体粒径分布与分形维数的影响因素[J].环境科学,2013,34(10):3975-3980.