Produced water treatment performance

Possible water sources for injection are sea water, fresh surface water, produced water or aquifer water (not from the producing reservoir). Once it has been established that there is enough water to meet demand (not an issue in the case of sea water), it is important to determine what type of treatment is required to make the water suitable for injection. This is investigated by performing laboratory tests on representative water samples. 

A growing specialty application for acrylonitrile is in the manufacture of carbon fibres. These are produced by pyrolysis of oriented polyacrylonitrile fibres and are used to reinforce composites for high-performance applications in the aircraft, defence and aerospace industries. Other minor specialty applications of acrylonitrile are in the production of fatty amines, ion exchange resins and fatty amine amides used in cosmetics, adhesives, corrosion inhibitors and water-treatment resins (Brazdil, 1991). 

Improved Disposal Water Treatment at Bahrain Oil Fields" by Mum el at. discusses solutions to environmental concerns at Awali field. As Awali field water cuts increased, the amount of produced water and oil carry-over increased. To avoid environmental damage, more efficient oil-removal equipment was necessary. A wide variety of equipment was evaluated and the vertical-tube coalescer was selected. A description of the unit is presented. Performance evaluations were conducted, and the units exhibited good oil-removal efficiencies... 

To ensure the best operation of watei treating equipment, it is necessary to optimize the performance of (he entire process train han dlmg produced water. Upgrading the performance of existing units will in turn greatly improve the performance of the final effluent-treatment equipment and result in overall lower costs... 

The treatment of bilge water and emulsions resembles that of the treatment of oil field brines and produced water. Chen et al. [25], using ferric chloride and other chemicals to enhance the performance of Membralox 0.2, 0.5 and 0.8 pm membranes, describe permeate fluxes between 1400 and 34001/m h. Without pretreatment however severe fouling occurred as well as break-through of oil. Zaidi et al. [26] report about the continuation of this work. They quote fluxes between 800 and 12001/m h, but also mention substantial lower fluxes in long term pilot tests using 0.8 pm membranes. In addition they indicate a drop in permeate flux caused by conditions of low pH, the presence of sea water, corrosion inhibitor, oil slugs or flow variations. 

The Standard Plant. The results presented in Figure 9 for the standard treatment plant indicate that effective removal (85% ) of suspended solids is produced by the flocculation-sedimentation process. Filter run length, as indicated by the time it takes to reach a head loss of 250 cm, is 28 hr. Filter ripening is rapid, and essentially complete removal of suspended solids is accomplished by the Alter throughout the run. The settling eflBciency, head loss development, and filtrate quality predicted by the model are consistent with typical water treatment plant performance. 

A comparison of Figures 9, 11, and 12 reveals that the performance of the water treatment plant is affected by the solids concentration in the raw water in complicated and unexpected ways. Influent water with the poorest water quality produces long filter runs and the best filter effluent quality. The standard influent produces good filtered water quality but the shortest filter runs. Influent water with the best quality... 

The RO unit is the pivotal process since water production by membrane separation declines with time mainly due to fording and other factors discussed in Chapter 2. The RO system must be run under conditions that minimise decline in flux while maintaining high product water quality. The pre-treatment system must be stable and reliable to ensure the RO unit operates continuously without frequent shutdowns for cleaning to restore flux and rejection. A stable RO membrane performance, in turn, is required to ensure the pohshing system produces water that meets the product water specifications without frequent shutdowns for regeneration of ion-exchange resins. 

The primary objeetive of this research was to evaluate the performance of two different MD teehnologies at pilot scale in the treatment of brine from thermal desalination plants. This highly saline brine mimics the produced water streams from oil/gas operations. 

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