Low-viscosity drag reducer

1. A method comprising the steps of:

(a) transporting a drag reducer through a first conduit, said drag reducer having a viscosity less than about 350 cP at a shear rate of 250 sec −1 and a temperature of 60° F.; and

(b) introducing the transported drag reducer into a fluid originating from a subterranean formation,

wherein said drag reducer has a solid particulate content of NAS 1638 Class 12 or less.

2. The method of claim 1 ,

said drag reducer having a viscosity less than about 250 cP at a shear rate of 250 sec −1 and a temperature of 60° F.

3. The method of claim 1 ,

said drag reducer comprising a non-crystalline drag reducing polymer having a molecular weight of at least 1×10 6 ,

said drag reducer comprising about 3 weight percent or less of the drag reducing polymer.

4. The method of claim 1 ,

said drag reducer having a viscosity less than 100 cP at a shear rate of 250 see −1 and a temperature of 60° F.,

said drag reducer having a solid particulate content of NAS 1638 Class 8 or less,

said drag reducer comprising a non-crystalline drag reducing polymer having a molecular weight of at least 2.5×10 6 ,

said drag reducer comprising about 0.1 to about 2 weight percent of the drag reducing polymer.

5. The method of claim 1 ,

said drag reducer comprising a non-crystalline drag reducing polymer having a molecular weight of at least 2.5×10 6 .

6. The method of claim 5 ,

said drag reducing polymer being water soluble.

7. The method of claim 5 ,

said drag reducing polymer being hydrocarbon soluble.

8. The method of claim 5 ,

said drag reducer comprising a hydrocarbon solvent,

said drag reducing polymer being substantially dissolved in the hydrocarbon solvent.

9. The method of claim 8 ,

said drag reducer being a product of solution polymerization carried out in the hydrocarbon solvent.

10. The method of claim 1 ,

said first conduit being at least 500 feet long and having a maximum inside diameter of 2.5 inches or less.

11. The method of claim 10 ,

said drag reducer being maintained at a temperature of less than about 60° F. during step (a),

said drag reducer exhibiting a pressure drop of less than about 5 psi per foot during step (a).

12. The method of claim 10 ,

during step (a), said first conduit being substantially devoid of any material having a viscosity less than the viscosity of the drag reducer.

13. The method of claim 1 ,

step (b) including introducing the transported drag reducer into a second conduit carrying the fluid originating from the subterranean formation.

14. The method of claim 13 ,

step (b) including providing at least a 10 percent drag reduction in the second conduit.

15. The method of claim 13 ,

said first conduit being at least 5,000 feet long and having a maximum inside diameter of 1 inch or less,

said drag reducer being maintained at a temperature of less than about 60° F. during step (a),

said drag reducer exhibiting a pressure drop of less than about 2.5 psi per foot during step (a),

step (b) including providing at least a 20 percent drag reduction in the second conduit.

16. The method of claim 13 ; and

(c) dissolving the drag reducer in the fluid carried by the second conduit.

17. The method of claim 16 ,

step (c) being performed without significant strand formation in the second conduit.

18. The method of claim 13 ,

said first conduit being part of a subsea umbilical line used to deliver power and chemicals to a remote subsea oil production facility.

19. The method of claim 18 ,

said second conduit being a subsea flowline for transporting a fluid produced from a subterranean formation.