An ejector is based upon Bernoulli’s principle, which states that when the speed of a fluid increases, its pressure decreases, and vice versa.įigure 1 shows the basic components of an ejector designed for use with gas. If the gas cannot be compressed high enough, it will need recompression and it may be more efficient to instead use a single compressor for all the compression.Įjectors can also be called eductors or jet pumps, although some only use the term eductors when the motive fluid is a liquid. They are useful when the gas (and motive gas) can be compressed high enough to get to its destination. Gas ejectors use high-pressure gas to compress surplus or low-pressure gas, flare gas, or vent gas. Here, they are an alternative to a vacuum pump or liquid ring compressor. Ejectors are also more complicated to design and use in production fields where new wells are regularly being drilled and wells are continuously changing output over time.Įjectors are also used in the downstream sector and other industries where vacuum systems occur. This is not available if the site mainly recovers oil. It can be less capital cost, lower operational costs, and less maintenance intensive.Īn ejector is not as common as a compressor in upstream processing (especially offshore applications) because it needs a high-pressure motive fluid (gas). It is an alternative to a vapour recovery unit (small compressor recovering gas) in some applications. An ejector is used in upstream processing to compress or boost the pressure of an entrained fluid.

Steam Ejector Design Software