【作者】 胡海；

【导师】 邱于兵； 郭兴蓬；

【作者基本信息】 华中科技大学 ， 应用化学， 2011， 硕士

【摘要】 目前,我国大部分油田进入“三次采油”阶段。随着油田开采的深入,大量的三次采油产出污水需要净化和处理,以满足污水回注或者外排的要求。由于三采污水的高温、高盐、高聚合物、高含烃、化学需氧量高而生物需氧量低的特点,同时又含有各种化学药剂,使得三采污水的处理难度越来越大,依靠现有的“二级沉降+二级过滤”传统处理工艺已不能满足要求。因此,研究适应性强、效果好、速度快的三次采油采出液处理技术是我国油田亟待解决的课题。本文针对我国某油田的三采污水,利用自制的污水处理装置,研究了脉冲电絮凝技术对该三采污水的处理效果。首先采用单因素研究方法,研究了一般处理条件,包括搅拌条件、电极板间距、NaCl添加量、处理时间、pH值等,对处理液CODCr、浊度的影响规律。然后,重点研究了脉冲电流参数(频率、幅值、占空比)的影响规律。在此基础上,选择脉冲电流幅值、频率和处理时间作为主要因素,采用正交实验方法进一步优化处理条件,对实验指标影响的主次次序进行分析,同时也对前面的单因素研究结果进行验证。采用优化参数条件,对脉冲电絮凝污水处理结果进行了验证。最后,从处理效果和电能消耗的角度,将脉冲电絮凝处理方法与化学絮凝法和直流电絮凝处理污水效果进行了比较。结果表明,一般处理条件和脉冲电流参数均对处理液CODCr、浊度有明显影响,需要针对具体污水的条件进行优化。本研究中,采用经过优化的操作参数,处理液能达到《国家污水排放标准》,说明脉冲电絮凝法可适用于油田三次采油污水的处理。正交实验中得出指标影响的主次次序为:电絮凝时间>峰值电流大小>>脉冲频率。在提供相同电量的情况下,脉冲电絮凝法产生的功率消耗小于直流法,同时羟基自由基的生成量也多于直流法。从处理效果来看,脉冲电絮凝法优于一般的投加聚合氯化铝、聚合硫酸铁的化学絮凝法。更多还原

【Abstract】 Nowadays,most of oil exploitation in China enters a stage of tertiary oil recovery. With the development of oil exploitation, increasing amount of tertiary oil recovery wastewater is needed to be treated so as to meet the requirements of wastewater re-injecting process and discharging in the environment. Generally the tertiary oil recovery wastewater has high temperature, high concentration of salt, polymer and hydrocarbons, high COD but low BOD, and many kinds of chemical agents contained. In this case, the treatment of this kind of wastewater is getting more and more difficult. Moreover, the traditional wastewater processing technology can hardly meet the need of treatment. So how to develop a new method to treat the wastewater from tertiary oil recovery with high adaptability, good effect and high efficiency, becomes an urgent issue in China.In the present work, pulsed current (PC) electroflocculation was applied to treat the tertiary oil recovery wastewater obtained from an oil field. Various factors, including stirring condition, electrode distance, concentration of sodium chloride, operating time, pH, and pulsed current parameters (amplitude, frequency and duty cycle) were investigated to find their effects on the treatment result. Then, based on these results, the amplitude, frequency and operating time were selected as the main factors, and the optimum treatment condition was determined by orthogonal experiments. Meanwhile, the selected factors effects were analyzed and proved by the single-factor experiment results. From the energy consumption and treatment affect, the PC electroflocculation method was compared with the traditional chemical treatment method and direct current (DC) electroflocculation method.The results show that various single-factors and pulsed current parameters have significantly effect on COD and turbidity of the treated wastewater, so they should be optimized based on the wastewater condition. In this work, with the optimized treatment condition, CODCr and turbidity of the treated wastewater can meet the requirements of National Integrated Wastewater Discharge Standard, which means that the pulsed current electroflocculation method can be applied effectively in the treatment of wastewater from tertiary oil recovery. The orthogonal experiment results analysis show that the importance of factors order is: operating time>amplitude>>frequency. Compared with the traditional DC method, under the same supplied electric quantity condition, the PC method consumed less electric energy and created more hydroxyl free radical. The treatment effect indicates that the PC electroflocculation method is much better than the traditional chemical flocculation treatments, using polyaluminium chloride and polymeric ferric sulfate, and the traditional DC electroflocculation method.更多还原