Certain chemicals can be mixed in with the injected fluid to help control corrosion, paraffin and emulsion problems.
ESP is a very versatile artificial lift method and can be found in operating environments all over the world.
They can be modified to handle contaminants commonly found in oil, aggressive corrosive fluids such as H2S and CO2, and exceptionally high downhole temperatures.
Increasing water cut has been shown to have no significant detrimental effect on the ESP performance.
It is possible to locate them in vertical, deviated, or horizontal wells, but it is recommended to deploy them in a straight section of casing for optimum run life performance.
Until recently, ESPs have come with an often prohibitive price tag due to the cost of deployment which can be in excess of $20,000.
This delivers a complete downhole system booster or back up - downtime is minimal, workovers cost less and there are savings in other operational areas.
Gas lifts can cope well with abrasive elements and sand, and the cost of workover is minimum.
Fluid operated valves require a rise in tubing pressure to open and drop to close.
Rod pumps are long slender cylinders with both fixed and moveable elements inside.
The pump is designed to be inserted inside the tubing of a well and its main purpose is to gather fluids from beneath it and lift them to the surface.
The movement of the plunger and the traveling valve helps to create a low pressure thus moving fluid up the well.
This technique is designed specifically to artificially lift the unique geometry of horizontal/deviated wells and also vertical wells that have deep or very long perforated intervals, or have too high of a gas liquid ratio (GLR) for conventional artificial lift methods.
In this design, the rod pump is placed in the vertical portion of the well above the deviated or perforated interval, while relatively low pressure-low volume gas is used to lift reservoir liquids from the deviated or extended perforated interval to above the rod pump.
This design overcomes high maintenance costs, gas interference issues, and depth limitations of installing conventional pumping systems into the deviated or extended perforated intervals and also overcomes the significant back pressure exerted on the reservoir by conventional gas lift.
The PCP is a flexible system with a wide range of applications in terms of rate (up to 5,000 bbl/d (790 m3/d) and depth 6,000 ft (1,800 m)).
They offer outstanding resistance to abrasives and solids but they are restricted to setting depths and temperatures.
They include; jet pumping involving a hydraulic pump and nozzle that transfers fluid momentum directly to the producing fluid or chamber lift which is a modified gas lift mechanism that has no back pressure.
There are also modified rod pumping design units that use either a winch or pneumatic mechanism to work.