Modified latex drag reducer and processes therefor and therewith
AssigneeConocoPhillips Company
InventorsWilliam Harris, Kenneth Smith, Stuart Milligan, Ray Johnston, Vincent Anderson
Life of this patent
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Abstract
A modified latex drag reducer and methods of making and using the drag reducer in order to reduce friction losses resulting from turbulent fluid flow through a conduit. Particularly, the modified latex drag reducer is formed from an initial latex which is a product of an emulsion polymerization reaction. The initial latex is then modified, preferably by admixing with at least one low HLB surfactant or at least one solvent, or both, to form a modified latex with an enhanced dissolution rate in a hydrocarbon stream over the initial latex.
Claims64
A latex drag reducer comprising:
- (a) a continuous phase;
- and
- (b) a plurality of particles of a high molecular weight polymer dispersed in said continuous phase, wherein said polymer particles have been formed via emulsion polymerization,
- said latex drag reducer having a hydrocarbon dissolution rate constant of at least about 0.004 min−1 in kerosene at 20° C.
A latex drag reducer comprising:
- (a) an aqueous continuous phase comprising at least one high HLB surfactant, at least one low HLB surfactant, and at least one solvent;
- and
- (b) a plurality of particles of a high molecular weight polymer dispersed in said continuous phase, wherein said polymer particles have been formed via emulsion polymerization.
A method of making a drag reducer, said method comprising the steps of:
- (a) using emulsion polymerization to produce an initial latex having an initial hydrocarbon dissolution rate constant;
- and
- (b) modifying said initial latex to thereby provide a modified latex having a modified hydrocarbon dissolution rate constant,
- said initial and modified latexes being colloidal dispersions comprising particles of high molecular weight polymer in a continuous phase,
- aid initial and modified hydrocarbon dissolution rate constants being measured in kerosene at 20° C.,
- said modified hydrocarbon dissolution rate constant being at least about 10 percent greater than said initial hydrocarbon dissolution rate constant.
A method of making a drag reducer, said method comprising the steps of:
- (a) combining water, at least one high HLB surfactant, and at least one monomer to thereby form a reaction mixture;
- (b) subjecting said reaction mixture to emulsion polymerizing at a polymerization temperature of less than about 60° C. to thereby provide an initial latex comprising particles of a drag reducing polymer having a weight average molecular weight of at least about 5×106 g/mol, wherein the mean particle size of said particles is less than about 1 micron;
- and
- (c) introducing at least one low HLB surfactant and at least one solvent into said initial latex in an amount sufficient enhance the hydrocarbon dissolution rate constant of said initial latex without substantially breaking or inverting said initial latex.
A method of reducing drag forces associated with turbulent flow of a fluid through a conduit, said method comprising:
- introducing a drag reducer into said fluid,
- said drag reducer being a colloidal dispersion comprising particles of a high molecular weight polymer dispersed in a continuous phase,
- said polymer particles having been formed via emulsion polymerization,
- said drag reducer having a hydrocarbon dissolution rate constant of at least about 0.004 min−1 in kerosene at 20° C.
Dependencies are inferred from the claim text.