Complex sentence: The spray pump is used for either pumping out liquid LNG to be used as fuel via a vaporiser or for cooling down cargo tanks, it can also be used for "stripping'" out the last of the cargo in discharge operations.
Split into simpler sentences: The spray pump is used for either pumping out liquid LNG to be used as fuel via a vaporizer, or for cooling down cargo tanks. It can also be used for "stripping'" out the last of the cargo in discharge operations.