Hydraulically actuated double-acting positive displacement pump system for producing fluids from a wellbore

A downhole pumping assembly, the assembly comprising:

• a. a first end and a second end defining an outer surface therebetween, the outer surface having a substantially constant outer diameter;
• b. a power assembly proximal the second end and configured to direct a power fluid;
• c. a production fluid assembly proximal the first end and configured to receive wellbore fluids and comprising a production piston configured to direct the received wellbore fluids towards the first end;
• d. a powered actuation assembly positioned adjacent the power assembly and in fluid communication therewith, the powered actuation assembly is operatively coupled to the production fluid assembly, the powered actuation assembly configured to receive the power fluid and to move the production piston via the operative coupling for directing the received wellbore fluids towards the first end;
• e. a central conduit that extends from the first end to the powered actuation assembly for conducting the power fluid therebetween;
• and
• f. an inner conduit positioned within the central conduit, wherein the inner conduit is configured to conduct a first fluid and wherein an annular fluid passage is defined between the central conduit and the inner conduit, wherein the annular fluid passage is configured to conduct a second fluid;
• wherein the first fluid is at a first pressure and the second fluid is at a second pressure and the first pressure is different from the second pressure, wherein the first fluid is the power fluid and the second fluid is an exhaust fluid or wherein the first fluid is an exhaust fluid and the second fluid is the power fluid.