ETHYLENE-TO-LIQUIDS SYSTEMS AND METHODS

1 .- 111 . (canceled)

112 . A method, comprising:

(a) directing an olefin-containing stream comprising an olefin into an ethylene-to-liquids (ETL) reactor comprising an ETL catalyst that facilitates conversion of at least a portion of said olefin to higher hydrocarbon compounds to yield an ETL product stream comprising said higher hydrocarbon compounds;

(b) directing at least a portion of said ETL product stream into a de-propanizer that separates said higher hydrocarbon compounds into a bottom stream comprising hydrocarbon compounds with four or more carbon atoms (C 4+ compounds) and an overhead stream comprising hydrocarbon compounds with three carbon atoms (C 3 compounds); and

(c) directing at least a portion of said C 3 compounds into said ETL reactor.

113 . The method of claim 112 wherein said olefin comprises ethylene, propylene, or a combination thereof.

114 . The method of claim 112 , further comprising, prior to (a), directing a hydrocarbon feedstream comprising feedstream hydrocarbons into a cracking reactor comprising a cracking catalyst that facilitates a cracking of said feedstream hydrocarbons to produce a cracked stream comprising cracked hydrocarbons, wherein said cracked hydrocarbons have a lower molecular weight than said feedstream hydrocarbons, and using at least a subset of said cracked hydrocarbons to generate said olefin-containing stream.

115 . The method of claim 114 , further comprising directing said cracked stream into a separations unit that separates said cracked hydrocarbons into a plurality of streams including said olefin-containing stream.

116 . The method of claim 112 , further comprising directing said overhead stream into a separations unit that condenses said C 3 compounds from said overhead stream to yield a diluent C 3 stream comprising said C 3 compounds.

117 . The method of claim 116 , wherein said separations unit comprises a partial condenser in fluid communication with a drum.

118 . The method of claim 116 , further comprising directing at least a portion of said diluent C 3 stream comprising said at least said portion of C 3 compounds into said ETL reactor.

119 . The method of claim 112 , further comprising directing at least an additional portion of said ETL product stream into a high-pressure separator that separates said higher hydrocarbon compounds into a liquid stream comprising hydrocarbon compounds having three or more carbon atoms (C 3+ compounds) and a gas stream comprising hydrocarbon compounds having less than three carbon atoms (C 3− compounds).

120 . The method of claim 119 , further comprising directing said gas stream into a recovery unit that separates said gas stream into a recovery overhead stream and a recovery bottom stream.

121 . The method of claim 120 , further comprising directing at least a portion of said recovery bottom stream into said ETL reactor.

122 . The method of claim 121 , further comprising using said recovery bottom stream as diluent to said olefin-containing stream.

123 . The method of claim 120 , further comprising, prior to (b), combining said recovery bottom stream with said at least said portion of said ETL product stream.

124 . The method of claim 112 , further comprising, between (a) and (b), directing said ETL product stream into a cooling unit that lowers a temperature of said ETL product stream.

125 . The method of claim 124 , further comprising directing said ETL product stream from said cooling unit into a phase separator that separates said ETL product stream into a liquid stream and a gas stream.

126 . The method of claim 125 , further comprising directing said liquid stream into said de-propanizer to produce said overhead stream and said bottom stream.

127 . The method of claim 125 , further comprising directing said gas stream into a separations unit that separates said gas stream into a first stream comprising hydrocarbon compounds with one carbon atom (C 1 compounds) and a second stream comprising hydrocarbon compounds with two or more carbon atoms (C 2+ compounds).

128 . The method of claim 127 , further comprising directing at least a portion of said second stream into said ETL reactor.

129 . A system, comprising:

an ethylene-to-liquids (ETL) reactor that receives an olefin-containing stream comprising an olefin and converts at least a portion of said olefin to higher hydrocarbon compounds with the aid of an ETL catalyst to yield an ETL product stream comprising said higher hydrocarbon compounds; and

a de-propanizer in fluid communication with said ETL reactor, which de-propanizer receives said ETL product stream and separates said higher hydrocarbon compounds from said ETL product stream into a bottom stream comprising hydrocarbon compounds with four or more carbon atoms (C 4+ compounds) and an overhead stream comprising hydrocarbon compounds with three carbon atoms (C 3 compounds).

130 . The system of claim 129 , further comprising (i) a cracking reactor that receives a hydrocarbon feedstream comprising feedstream hydrocarbons and, with the aid of a cracking catalyst, facilitates cracking of said feedstream hydrocarbons to produce a cracked stream comprising cracked hydrocarbons, wherein said cracked hydrocarbons have a lower molecular weight than said feedstream hydrocarbons, and (ii) a separations unit in fluid communication with said cracking reactor, which separations unit receives said cracked stream and separates said cracked hydrocarbons into a plurality of streams comprising said olefin-containing stream.

131 . The system of claim 129 , further comprising a separations unit in fluid communication with said de-propanizer, which separations unit condenses said C 3 compounds from said overhead stream to yield a diluent C 3 stream comprising said C 3 compounds.