Method and system to produce hydrocarbon feedstocks
A method that combines a fuel cell with a Gas Recovery Unit (GRU) to a methanol plant to produce methanol at near zero GHG emissions. The fuel cell generates steam, carbon dioxide and electricity. A GRU unit condenses, separates, recovers, pressurizes and reheats the fuel cell anode exhaust stream. The GRU prepares a stream of natural gas and steam to feed the fuel cell anode and a stream of carbon dioxide and air to feed the fuel cell cathode. The GRU also prepares streams of carbon dioxide and steam as reactants for the stoichiometric mixture with natural gas to produce synthesis gas in an electric catalytic reformer at a methanol plant. The electric catalytic reformer uses electricity, steam and/or carbon dioxide reactants produced by the fuel cell to produce synthesis gas for conversion to methanol with low GHG emissions.
1. A method of producing synthesis gas using a fuel cell having an anode and a cathode, a Gas Recovery Unit (GRU), and an electric catalytic reformer, the method comprising the steps of:
operating the fuel cell to generate electricity and an exhaust stream comprising steam and carbon dioxide, the fuel cell being connected to a power distributor;
using the GRU, conditioning and separating the exhaust stream to produce streams of steam and carbon dioxide;
producing a reformer input stream by combining a stream of methane, the stream of carbon dioxide, and the stream of steam according to a stoichiometric ratio required to produce a stream of synthesis gas;
reacting the reformer input stream in the electric catalytic reformer to produce the stream of synthesis gas, the electric catalytic reformer being powered by the power distributor; and
using a power generator, recovering heat from the stream of synthesis gas to produce electricity, the power generator being connected to the power distributor.
2. The method of claim 1 , wherein the stream of synthesis gas is reacted in a synthesis reactor to produce a petrochemical.
3. The method of claim 2 , wherein heat is recovered from the synthesis reactor using a Rankine Cycle or an Organic Rankine Cycle power generator that is connected to the power distributor.
4. The method of claim 1 , wherein the GRU receives a natural gas stream, the GRU conditioning a first portion of the natural gas stream as a fuel gas stream to feed the fuel cell anode, and conditioning a second portion of the natural gas stream as the stream of methane.
5. The method of claim 4 , wherein the GRU further conditions a fuel stream of steam that is mixed with the fuel gas stream to feed the anode of the fuel cell.
6. The method of claim 1 , wherein the stoichiometric ratio of methane, carbon dioxide, and steam is 3:1:2.
7. The method of claim 6 , further comprising the step of reacting the synthesis gas in a methanol synthesis reactor to produce methanol.
8. The method of claim 7 , further comprising the step of recovering heat from the methanol synthesis reactor using a power generator to produce electricity, the reactor power generator being connected to the power distributor.
9. The method of claim 8 , wherein the power generator is a Rankine Cycle or an Organic Rankine Cycle power generator.
10. The method of claim 1 , wherein the fuel cell is operated to produce a desired amount of steam and carbon dioxide, and any excess electricity is sold to a third-party consumer.
11. A system for producing hydrocarbon-based products, comprising:
a power distributor;
a fuel cell having an anode and a cathode, the fuel cell generating electricity and an exhaust stream comprising steam and carbon dioxide, the power distributor receiving electricity from the fuel cell;
a Gas Recovery Unit (GRU) connected to the fuel cell, the GRU being adapted to:
condition an input stream of natural gas to produce a first methane stream and a second methane stream, the first methane stream comprising fuel gas for the fuel cell;
condition the exhaust stream from the fuel cell to produce a stream of steam and a stream of carbon dioxide; and
control an output of the second methane stream, the stream of steam and the stream of carbon dioxide according to a stoichiometric ratio;
an electric catalytic reformer that receives the second methane stream, the stream of steam, and the stream of carbon dioxide, the electric catalytic reformer being powered by electricity from the power distributor to produce a stream of synthesis gas; and
a power generator that recovers heat from the stream of synthesis gas to produce electricity, the power generator being connected to the power distributor.
12. The system of claim 11 , further comprising a synthesis reactor that reacts the stream of synthesis gas to produce a petrochemical in an exothermic reaction.
13. The system of claim 12 , further comprising a power generator comprises a Rankine Cycle or an Organic Rankine Cycle that generates electricity from heat produced by the synthesis reactor, the power generator being connected to the power distributor.
14. The system of claim 12 , wherein the stoichiometric ratio of methane, carbon dioxide and steam is 3:1:2, and the synthesis reactor is adapted to produce methanol.
15. The system of claim 11 , wherein the GRU is adapted to mix a portion of steam obtained from the exhaust stream with the first methane stream as a fuel stream for the anode of the fuel cell.
16. The system of claim 11 , wherein fuel cell is adapted to operate the power distributor is adapted to supply excess electricity to a third party consumer, the excess electricity being generated fuel cell is operated to produce a desired amount of steam and carbon dioxide, and any excess electricity is sold to a third-party consumer.