5 replies to this topic

[bobjay]

please i need to know the benefit of saturator during the production of syngas. why is the natural gas saturated? how does the saturator work and tips on how to size and design one. thanks 

[Padmakar Katre]

please i need to know the benefit of saturator during the production of syngas. why is the natural gas saturated? how does the saturator work and tips on how to size and design one. thanks

Hi,
Just a general comment "to have mass transfer between gas-liquid on contact, the basic criteria is both should be saturated i.e. vapor at it's dew point and liquid at its bubble point". The typical example is acid gas saturation by water before it is sent to acid gas recovery unit (e.g.amine sweetening unit.)

[Technical Bard]

please i need to know the benefit of saturator during the production of syngas. why is the natural gas saturated? how does the saturator work and tips on how to size and design one. thanks

In some plant designs, a saturator column is used to add water to the syngas prior to a shift reactor. Other designs simply inject steam. The purpose is to provide enough water so that the steam to carbon ratio of the syngas entering the shift reactor is high enough to approach thermodynamic equilibrium for the reactions, as well as avoid side reactions that can produce unwanted species (e.g. carbon, formic acid, methanol).

[bobjay]

please i need help on how to do the preliminary design of a saturator. how can i go about it?

[hana85]

please i need to know the benefit of saturator during the production of syngas. why is the natural gas saturated? how does the saturator work and tips on how to size and design one. thanks

In some plant designs, a saturator column is used to add water to the syngas prior to a shift reactor. Other designs simply inject steam. The purpose is to provide enough water so that the steam to carbon ratio of the syngas entering the shift reactor is high enough to approach thermodynamic equilibrium for the reactions, as well as avoid side reactions that can produce unwanted species (e.g. carbon, formic acid, methanol).

Hi technical bard!
how do u calculate the much water and gas should be fed to the vessel to get the desired steam to carbon ratio?

[Technical Bard]

please i need to know the benefit of saturator during the production of syngas. why is the natural gas saturated? how does the saturator work and tips on how to size and design one. thanks

In some plant designs, a saturator column is used to add water to the syngas prior to a shift reactor. Other designs simply inject steam. The purpose is to provide enough water so that the steam to carbon ratio of the syngas entering the shift reactor is high enough to approach thermodynamic equilibrium for the reactions, as well as avoid side reactions that can produce unwanted species (e.g. carbon, formic acid, methanol).

Hi technical bard!
how do u calculate the much water and gas should be fed to the vessel to get the desired steam to carbon ratio?

A process simulator can be used to estimate the number of stages you will need, and the surplus of water over what you need to saturate the gas. You must supply enough water that there is still significant liquid water at the bottom of the saturator. You will need to do heat transfer calculations for the packed beds in the column to determine the amount of packing you need, since the heat transfer is often governing over the mass transfer of water to the gas phase (the column is heating the gas with hot water).


It is impossible to use a saturator to reach the desired Steam/Carbon ratio, so you will need to inject some steam directly into the gas upstream of the shift reactor.

A saturate column needs to be coupled to a quench column after the shift reactor - this column uses the cooler water from the bottom of the saturator to quench the shift product, and condense the excess water from the shift effluent stream. This heats the water, which is then pumped back to the saturated to be reused.