Generating methanol using ultrapure, high pressure hydrogen
View Patent ↗In various implementations, methanol is produced using a (CO+H 2 ) containing synthesis gas produced from a combined PDX plus EHTR or a combined ATR plus EHTR at a pressure of 70 bar to 100 bar at the correct stoichiometric composition for methanol synthesis so that no feed gas compressor is required for the feed to the methanol synthesis reactor loop.
1. A method for producing methanol, comprising;
producing oxygen in an air separation plant with air compressors driven by a gas turbine;
heating a hydrocarbon feed stream using exhaust from the gas turbine;
exothermically reacting a first portion of the heated hydrocarbon feed stream with at least one of steam or an oxidant gas comprising molecular oxygen to produce an exothermically generated syngas product;
endothermically reforming a second portion of the hydrocarbon feed stream with steam over a catalyst in a heat exchange reformer to produce an endothermically-reformed syngas product, wherein at least a portion of heat used in generation of the endothermically-reformed syngas product is obtained by recovering heat from the exothermically-generated syngas product and the endothermically reformed syngas product;
combining the exothermically generated syngas product and the endothermically-reformed syngas product to produce a combined syngas stream;
producing steam in a waste heat boiler by cooling the combined syngas stream, where the combined syngas stream leaving the waste heat boiler has a pressure from 70 bar to 100 bar;
separating water from the cooled combined syngas to produce a methanol plant feed at substantially reaction loop pressure and having less than about 2% CH 4 and less than about 0.2% H 2 O;
after separating water, passing the cooled combined syngas to a methanol plant; and
combining methanol plant combustible effluent with methane fuel to the gas turbine.
2. The method of claim 1 , wherein the exothermically-generated syngas product is generated using a partial oxidation burner followed by a catalytic reforming section in a convectively heated steam plus hydrocarbon reformer.
3. The method of claim 1 , wherein the hydrocarbon feed stream includes methane.
4. The method of claim 1 , wherein the exothermically generated syngas product has a temperature greater than about 1000° C.
5. The method of claim 1 , wherein the endothermic reforming occurs at a pressure of about 70 bars or greater.
6. The method of claim 1 , further comprising producing substantially pure methanol using the cooled combined syngas at a rate of about 700 metric tons per day.
7. The method of claim 6 , wherein the substantially pure methanol includes about 95% or greater methanol.
8. The method of claim 1 , wherein the cooled combined syngas is passed to the methanol plant independent of using a feed stream compressor.
9. The method of claim 1 , wherein the cooled combined syngas is passed to the methanol plant at a pressure in a range from about 70 to 100 bars.
10. The method of claim 1 , wherein the second portion of the hydrocarbon feed stream includes a steam to active carbon ratio in a range of about 5 to 8.
11. The method of claim 1 , wherein a gas-heated catalytic reformer (GHR) produces the endothermically-reformed syngas product by using catalyst filled tubes mounted in a vertical bundle with an inlet tube sheet at a top end and open bottom outlet ends.