Selecting the right dra type
As mentioned earlier, the DRA always comes with a carrier system. Depending on what kind of system is used, one can find three different DRA types:
- High viscosity gel
- Low viscosity gel
- Emulsion
Each of them is a result of evolution. The selection criteria for finding the right type are based on transportation, handling and storage aspects. Often there aspects are very dominant and the selection must be made case by case. The following table illustrates the situation.
| DRA Type | Advantages | Disadvantages |
|---|---|---|
| High Viscosity Gel | Relative small volumes | Difficult to handle, Heated pressurized feed tanks etc needed |
| Low Viscosity Gel | Easy to handle, no special feed arrangements needed | Slight higher volumes to handle |
| Emulsion | Very small volumes | Limited storage time of homogenization needed |