Performance Evaluation Of Depth Profile Control Agent

With the oilifeld development, many oil ifelds have been in medium、high water cutperiod development stage, comprehensive water cut oil reached more than80%，the injectedwater channeling along high permeability layer phenomenon is serious, have lower waterlfooding recovery problem, contradiction of waterlfood development is more and moreobvious. Must use the new technology to enhance oil production rate, depth profile controlagent lfooding and polymer flooding technology is mature day after day.Bifunctional crosslinking agent is on the basis of water soluble phenolic resin，Introduction part of urea-formaldehyde resin in the molecule，Crosslinking agent moleculeshave the hydroxymethyl and urea-formaldehyde resin on hydroxymethyl two crosslinkinggroups crosslinking agent molecules of phenolic resin. The preferred formula of depth proiflecontrol agent:0.2%composite ion polyacrylamide (15000000，cationic degree5%)+0.3%bifunctional crosslinking agent, between24h-30d adjustable gel time, gel strength more than7000mPa? s; breakthrough pressure greater than0.5MPa/cm. On core plugging rate wasmore than90%. Delay of water-swelling polyacrylamide grain expansion multiple of20?150times (wt%); After8hours start slow swelling, after4?5days achieve expansion balance.Core experiment showed that, most proifle control agent get into high permeabilitycores，The high permeability reservoir have high degree of blockage, low permeability coreshave low degree of blockage, low plugging rate. As for washing the deeper reservoir poreplugging, profile control agent has good effect. The pore throat size and solid particle sizeratio is9:1，the concentration of solid particles is8%，solid particles can be smoothly into thecore，realize stable injection.In this paper, preferably a depth proifle control agent, the performance evaluation of its,and conduct simulation evaluation experiment to the core with the proifle control agent.Proifle control mechanism, inlfuence factors of water flooding recovery, recovery of differentinjection modes，slow expansion mechanism of bentonite particles are analyzed.