Research On Processing Technology Of Produced Fluid Containing Fracturing Fluid

In recent years,the average annual fracture of old wells in low permeability block of Daqing oilfield range from 60 to 80.More than 95 % of new wells need to be put into production after fracturing.In the Longhupao Union Station area,large scale fracturing measures should be taken for the effective use of ultra-low permeability in Gaotaizi layer.Produced liquid of oil well after fracturing contain a lot of chemical additives such as guar gum.The composition of produced liquid is complex and the emulsification situation is serious.These additives enter the Union station directly with the produced liquid,and after the treatment of oil-produced liquid,the suspended substance content is not up to standard.This will cause great impact on the crude oil dehydration system and sewage treatment system of the Union station.This paper aims to study the factors affecting the demulsification and dehydration of produced fluid in residual fracturing fluid,and using the digital display viscosity tester to measure the rheological characteristic of the flowback fluid which with the fracturing fluid;using particle image analyzer to detect the emulsion condition of produced fluid containing fracturing fluid;analysis of the influence of emulsion containing fracturing fluid on dewatering effect;using interfacial tensiometer measures the interfacial tension of produced liquid;using Zeta potentiometer to measure the potential of different kinds of fracturing fluid;determine the factors that affect the stability of the emulsion;perform a demulsifier with indoor screening and compounding;and conduct mine tests,assessment the demulsification dehydration effect of demulsifier.Experimental results show that,factors of causing the dehydration of produced liquid containing fracturing fluid without reaching the standard is in turn: Dosing agent> Thickener> Anti-swelling agent> Viscosity reducing agent> Stabilizer> Belling agent> Fungicide;the optimum combination of the demulsifier for PT6682B and PS-639-06 was 1: 3;the optimum dosing temperature was determined to be 65?;optimum voltage,time and pressure,water content and temperature of different fracturing fluid content were determined.The optimum operating parameters of "five in one" device under five different content fracturing fluid conditions are determined.