FORMATION SAMPLER WITH CLEANING CAPABILITY

Sampling tools are used to extract samples of underground reservoir fluids. The extracted samples can either be analyzed down-hole or stored in a container for subsequent laboratory analyses. In either case, the fluid sample must be representative of both the chemical composition and physical properties of the formation fluid about the volume of sampling acquisition. Often, one sampling tool is used to acquire fluids from several locations within a reservoir. It is highly likely that fluid sampled at a first location in the reservoir may have adhered to the inner walls of the flow line or other hydraulic components of the sampling tool. Consequently, fluid extracted from a second location within the same reservoir may be contaminated by that remaining from the first acquisition. As a consequence, the chemical composition and physical properties determined by analyses of the second fluid may not actually be of the formation fluid but of a mixture of the first and second fluid and thus be unrepresentative of the formation fluid at that second location. Such mixing of fluids from two zones of the same reservoir may plausibly lead to wrong decisions regarding the fluid type within the reservoir. One such example regards the distinction of a fluid as a volatile oil when it is actually a gas condensate, a decision that would have catastrophic consequences on the designed and commissioned surface separator systems.