Oil and gas industries involve three main stages of oil and gas operations- upstream, midstream, and downstream. Upstream operations consist of activities that involve exploration, discovery, extraction and production of crude oil and natural gas.
Following the initial production stage, many integrated and specialised oil companies deal with the processing, transporting, and marketing of natural gas, oil and other liquids during the midstream phase of operations.
Then comes the final downstream stage, where the oil and gas are refined and distributed to people to be used as consumer goods.
Before reaching consumers, the chemicals are refined in specialised oil and gas chambers that contain various structures to produce the manufactured products. One of the important devices responsible for refining is a pump.
Petrochemical pumps used in downstream operations
Pumps are used in various production and manufacturing industries. They form an essential part of oil and gas drilling rigs to accelerate the transfer of fluid from one location to another, without which oil refineries can not operate.
Petrochemical pumps are used to refine petrochemicals, which are simply chemicals derived from petroleum and other sources like natural gas and crude oil.
The types of downstream petrochemical pumps used in oil and gas downstream operations are discussed below:
- Piston pumps
The piston pump is a reciprocating pump that consists of one or more pistons enclosed in a cylinder and moves through the energy supplied by an electric motor via a crankshaft. This is done to pressurize the oil from one end of the pumping chamber to the other.
When the oil enters the pumping chamber through the inner valve, the crankshaft rotates and moves the piston upward via connecting rod to increase the capacity of the cylinder. As the fluid fills in the whole cylinder, the crankshaft rotates further to push the piston downward and apply pressure to get the fluid out via the discharge outlet.
- Diaphragm pumps
The diaphragm pump is another type of reciprocating positive displacement pump. It uses a flexible band of rubber called a diaphragm that reciprocates with the piston rod. These pumps work just like piston pumps with the only difference being the presence of a diaphragm.
As the fluid enters via the inlet valve, the diaphragm creates a vacuum to adjust the volume of fluid. As the cylinder fills up, it decreases the chamber volume and pressurizes the fluid via the outlet valve out of the discharge port of the chamber.
- Magnetic drive pumps
This type of pump is unique as it is driven by the force of magnetism rather than being connected to an electric motor. Magnetic drive pumps are a type of centrifugal pumps that contain impellers to distribute the fluid.
The motor drive in a mag drive pump has a cylindrical shell that contains an outer ring of magnets. The inner magnet ring is separated by the outer one by a thin-walled can.
The magnetic force from the outer magnets provides the flux to the inner magnets which in turn propel the impeller to rotate and drive the fluid.
The magnets used in magnetic drive pumps are samarium cobalt and neodymium iron boride.
- API pumps
API 610 pumps are designed according to the standards of the American Petroleum Institute (API) 610 and they come in different forms, employing different methods of pumping. These mainly include centrifugal pumps that come in different configurations. Some types of API pumps are:
- Horizontal split case pumps
- End suction pumps
- Multistage pumps
- Vertical inline pumps
- Vertical turbine pumps
To summarise, the downstream operations in the oil and gas industry involve the refining of the petrochemicals extracted and transported through the upstream and midstream phases.
The refining is achieved by the use of different petrochemical pumps to accelerate the movement of fluid, which operate through different mechanisms of fluid propulsion.