the invention relates to an enhanced recovery method that optimizes the stages of pumping , transport and surface treatment of the production effluent . the method of the invention comprises the following stages : injecting into said reservoir a sweep fluid comprising at least one polymer so as to displace said hydrocarbons towards at least one production well , collecting a production effluent comprising the hydrocarbons through production well , injecting into said effluent at least one degradation agent for said polymer .