Re: Corn - Investment Advice
MasterBlaster beat me to the punch. I used to design methanol plants.
MB described naptha reforming to make syngas and the old high pressure methanol process. I don't think either is used anymore anywhere.
As brewer said, we use natural gas today. It is kind of a neat process. Since you asked (ahem!), I will tell you all about it.
Typically, the natural gas is mixed with steam, heated under pressure, then flows down through a bed of catalyst that looks like big beads inside a big (~10" diameter x 40 feet long) high-nickel alloy tube. Said tube is one of hundreds (770 in one plant I helped with) in vertical rows inside a big furnace which heats the tubes like you wouldn't believe. The reaction to make hydrogen and carbon monoxide from methane and steam absorbs heat--a lot of heat. The tubes look dark inside the yellow-hot furnace. The product syngas comes out hot as Hell, is collected and cooled by making steam. (The same plant is used to make hydrogen al by itself. It is by far the cheapest way to make hydrogen.)
After cooling, it is compressed to between 50 and 100 atmospheres and put into a "synthesis loop," where it is recirculated through another reactor (just a big bottle this time). The most common catalyst today is copper deposited on little tablets of zinc oxide that look like rabbit food. The effluent from the reactor is cooled to condense the methanol. Only about 5% of the syngas more or less is converted per pass, so the unconverted syngas is recirculated back to the reactor and eventually almost all of it is converted to methanol. There is some water that comes out with the methanol plus traces of impurities. The raw methanol is made pure in two distillation columns.
And that's it.
As I understand today's situation, most methanol plants operating today are using free gas or gas with negative value. (i.e., gas associated with oil coming up out of the ground. Some countries won't allow such associated gas to be flared anymore. In order to pump the oil--which is what the oil companies really want--they have to do something with the gas. Hence 'free' gas, liquified natural gas--LNG--and 'gas-to-liquids', which include methanol and synthetic gasolene and diesel.) Nobody who has to pay for natural gas can make money making methanol these days.
Ed The Gypsy
Will design methanol plants for food.
"I am not in a hurry.
I am retired.
And I don't care how big your truck is."