Produced water treatment hydrocyclones

In Hydrocyclones A Solution to Produced Water Treatment, Meldrum presents the basic design principle of a dc-oilmg hydrocy leone. System design, early operational experiences, and test results on a full-scale application in the North Sea are discussed. Oil-removal efficiency was seen to rise with increasing reject ratio up to around 1%, producing acceptable outlet concentrations Early field test results on a tension leg platform in the North Sea are discussed. Preliminary data on a pumped system are also given. 

Since the early 1980s, hydrocyclones have been used in produced water treatment to de-oil the water prior to discharge. Hydrocyclones used to de-oil the water are referred to as "hquid-liquid de-oiling" hydrocyclones. Liquid-liquid hydrocyclones are further classified as static or dynamic hydrocyclones. 

MF or UF or their combined solutions are suitable technologies to separate oils from water. Bilstad and EspedaF" compared MF and UF membranes in a pilot trial to treat the North Sea oil field-produced water. By UF membrane treatment, the total hydrocarbon concentration can be reduced to 2 from 50 mg/L (96% removal). Benzene, toluene, and xylene (BTX) were reduced by 54%, and some heavy metals like Cu and Zn were removed to the extent of 95%. Lee and Frankiewicz of NATCO group tested a hydrophilic UF membrane to treat oil field-produced water, placing the membrane units after a hydrocyclone used to desand and deoil the wastewater. At the end of the process, the oil and gas concentration was reduced to less than 2 mg/L. 

Liu, S., Zhao, X., Dong, X., Miao, B., and Du, W. 2005. Treatment of Produced Water From Polymer Flooding Process Using a New Type of Air Sparged Hydrocyclone. Paper SPE 95343 presented at the SPE Asia Pacific Health, Safety and Environment Conference and Exhibition, Kuala Lumpur, 19-21 September. DPI 10.2118/95343-MS. 

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