Research on key technologies for treating produced water of gasfield
The produced water from the gasfield has problems such as high output,complex water quality and severe emulsification.At the same time,the gas gathering stations in the gas area are widely distributed and far away,making it difficult to transport and treat the produced water.In order to further improve the transportation efficiency of produced water,optimize water quality indicators,strengthen the oil removal effect,and explore the potential for increasing light hydrocarbon production,we have comprehensively implemented the"transportation pipeline transportation"process transformation,optimized the hydraulic sin-gle cylinder double acting plunger pump to ensure transportation efficiency,and formed the"demulsification+oil-water separation+air flotation+cyclone separation"water treatment process.At the same time,we have conducted experiments on the mixed transportation of oil and water and the compatibility of chemicals to evaluate the operational effect of the process.Research has shown that,(1)Based on the transformation of the production water pipeline transportation process,adopting the gas gathering station treatment plant oil-water mixed transportation mode can effectively improve production efficiency,reduce employee labor in-tensity,and reduce production and operation costs.(2)Adopting oil-water mixed transportation and undergoing the"front-end demulsification+oil-water separation"process,the oil separa-tion effect can be strengthened,and the oil production rate is increased by 4.73%compared to the single large tank sedimentation treatment mode.(3)By combining the process of"de-mulsification+oil-water separation+air flotation+cyclone separation"and considering the wa-ter treatment capacity of 60 m3/h,key factors affecting the water treatment effect,such as seven optimal dosage type,dosage sequence and dosage quantity,were determined.After treatment,the removal rate of suspended solids in water quality was 64%,and the removal rate of oil was 92%.