Methods, systems, and apparatuses for utilizing a Fischer-Tropsch purge stream

A system for producing Fischer Tropsch (“FT”) hydrocarbons, the system comprising:

• a. a syngas preparation unit configured to produce a syngas comprising hydrogen and carbon monoxide from a carbonaceous feedstock, wherein the syngas preparation unit is a steam methane reformer;
• b. a syngas conditioning unit, fluidly connected to an output of the syngas preparation unit, configured to condition the syngas to remove a process condensate stream from the syngas and produce a conditioned syngas;
• c. an FT reactor, fluidly connected to an output of the syngas conditioning unit, and having an FT catalyst, configured to operate under FT conditions to receive the conditioned syngas as an input and to make FT liquid hydrocarbons, with an FT tail gas and an FT water stream as by-products;
• d. an FT tail gas flowline to transport the FT tail gas from the FT reactor to the syngas preparation unit for use as a feed;
• e. a diverting line configured to remove an FT tail gas purge stream, comprising a portion of the FT tail gas, from the FT tail gas in the FT tail gas flowline;
• f. a water gas shift (“WGS”) reactor fluidly connected to the diverting line to receive the FT tail gas purge stream, and having a water gas shift catalyst positioned therein, configured to convert carbon monoxide and water in the FT purge stream exposed to the water gas shift catalyst under WGS conditions at least in part to carbon dioxide and hydrogen to form a shifted FT purge stream;
• g. a carbon dioxide removal unit fluidly connected to an output of the WGS reactor and configured to remove at least a portion of the carbon dioxide from a stream comprising the shifted FT purge stream to form a carbon dioxide stream and a treated purge stream;
• and
• h. a sixth flowline to transport the carbon dioxide stream to the syngas preparation unit as an input.