ELECTROCAOGULATION - FORWARD OSMOSIS PROCESS AS AN EFFICIENT METHOD FOR THE TREATMENT OF PRODUCED WATER FOR POSSIBLE RECYCLING AND REUSE

Abstract

Produced water (PW) is considered to be the largest source of industrial wastewater associated with oil and gas extraction operations leading to major impacts on the environment. Existing treatment technologies involve partially treating PW through removing the suspended solids, such as heavy metals, without removing organic components and re-injecting the water underground using water disposal injection wells. No alternate advanced treatment options on a commercial scale are available at present due to the limitations of existing PW treatment technologies, associated with their maintainability, sustainability, cost, and level of quality improvement. This thesis includes detailed literature review that discusses the latest advanced technologies for PW treatment aimed at reusing the full stream capacity of PW and eliminating the need for wastewater disposal via injection. It is concluded that researchers should focus on hybrid treatment technologies in order to remove the pollutants from PW, effectively allowing for its reuse. Moreover, produced water treatment on Lab scale using Forward osmosis system (FO) as a polisher phase is examined to determine the efficiency of pollutant removals and optimum range of parameters. The application of FO process with the use of Sodium Chloride (NaCl) as Draw solute (DS) has been investigated to treat the real produce water and to determine the efficiency of pollutant removals. The FO treatment experiment work carried out using partially treated PW after completing the initial treatment phase with Electrocoagulation (EC) process. The result showed the efficiency of PW pollutants removal by analyzing a number of parameters of pollutants including ions, metal and BEXT, Chemical Oxygen Demand (COD), Total Organic Carbon (TOC) and Oil and Greases (O&G) were tested for all conducted experiments as well. Electro-coagulation combined with an osmotic system for PW treatment appears to be an attractive system when comparing its results and performance with those of other technologies such as AOPs and bioelectrochemical and biological approaches, or even a single treatment in the tertiary phase. However, several limitations need to be addressed to de-bottleneck the existing challenges and improve the overall system to make it suitable for commercial use.