| 摘要 |
<p>Low viscosity, high concentration drag reducing agents may be prepared by slowly adding a liquid, non-solvent (e.g. isopropyl alcohol) for a drag reducing polymer (e.g. a polyalphaolefin) to a mixture of the polymer and the solvent (e.g. kerosene) in which the polymer is dissolved. When enough non-solvent is added, the polymer precipitates into fine particles. The supernatant mixture of solvent and non-solvent is then removed from the precipitated polymer slurry concentrate. Further solvent contained in the slurry concentrate may be removed by evaporation or further extraction with the liquid, non-solvent. The resulting slurry concentrate dissolves rapidly in flowing hydrocarbon streams to reduce the drag therein, and gives exceptionally good drag reducing results at low concentrations. Additionally, no injection probes or other special equipment is required to introduce the drag reducing slurry into the hydrocarbon stream, nor is grinding of the polymer necessary to form a suitable DRA slurry.</p> |
