Two-stage catalytic heating systems and methods of operating thereof

A method of operating a two-stage catalytic heating system using fuel and oxidant to generate heat, the method comprising:

• flowing liquid fuel and a first oxidant portion into a first-stage catalytic reactor comprising a first-reactor oxidant inlet, a first-reactor fuel inlet, a fuel supply configured to supply the liquid fuel and comprising a fuel delivery device fluidically coupled to the first- reactor fuel inlet comprising a fuel pump, a first-reactor catalyst, and a first-reactor outlet, wherein the liquid fuel and the first oxidant portion form a fuel-rich mixture converted into a syngas when contacting the first-reactor catalyst;
• and
• flowing the syngas and a second oxidant portion into a second-stage catalytic reactor comprising a second-reactor catalyst configured to operate at a different temperature than the first-reactor catalyst, a heat exchanger integrated into the second-stage catalytic reactor and configured such that thermal fluid may be passed through, and a fuel-oxidant mixer, wherein the syngas and the second oxidant portion form a fuel-lean mixture converted into exhaust when contacting the second-reactor catalyst, wherein:
• the first-reactor oxidant inlet is coupled to a first oxidant delivery device,
• the first oxidant delivery device is configured to control a first oxidant portion flow rate delivered to the first-reactor oxidant inlet,
• a syngas line is fluidically coupled to the first-reactor outlet,
• another heat exchanger is connected to the syngas line and configured to control the temperature of syngas entering the second-stage catalytic reactor,
• the fuel-oxidant mixer is fluidically coupled to the syngas line and to a second oxidant delivery device configured to control a second oxidant portion flow rate delivered to the fuel-oxidant mixer, and
• the liquid fuel is selected from a list consisting of methanol, ethanol, and isopropanol.