Downhole activatable annular seal assembly

A system for providing an active pressure differential within a wellbore, the system comprising:

• an active pressure differential device having an outer housing and a fluid pump component;
• an annular seal assembly for providing a fluid seal between the housing of the active pressure differential device and a wellbore sidewall, the seal assembly comprising:
• a selectively inflatable seal element that is actuatable between a first position wherein the seal element is uninflated and a second position wherein the seal is inflated to provide a fluid seal;
• and
• a hydraulic inflation system for selective actuation of the seal element between its first and second positions, the hydraulic inflation system comprising a hydraulic fluid chamber having an open end that is exposed to drilling mud flow, the drilling mud flow providing a fluid pressure source for inflation of the seal element to its inflated position.

A system for providing an active pressure differential within a wellbore, the system comprising:

• an active pressure differential device having an outer housing and a fluid pump component;
• an annular seal assembly for providing a fluid seal between the housing of the active pressure differential device and a wellbore sidewall, the seal assembly comprising:
• a seal element that is set against the wellbore sidewall to provide a fluid seal, and
• a fluid passage that allows wellbore fluids to bypass the seal element as the active pressure differential device and annular seal assembly are run into the wellbore.