Letter: CCS will reduce CO2 emissions, hasten reduction of fossil fuels, ensure flexible green fuel options

By Letter to the Editor on March 4, 2022.

In response to Jan. 22 letter to the editor, “Hatters shouldn’t be happy about carbon capture hub”

Dear editor,

Carbon capture and storage (CCS) is necessary for the reduction of carbon dioxide (CO2) emissions from the petrochemical industry and will also be required as part of future hydrogen (H2) production.

Most petrochemical production requires “syngas,” a mixture of H2, CO2, and CO. It is used to make products that will be required well into the future like methanol and ammonia.

Syngas can be made from natural gas (> 90% methane or CH4) by combining it with either water (steam reforming) or oxygen (auto-thermal reforming).

Steam reforming uses a large furnace heated by natural gas resulting in exhaust from a stack with composition similar to exhaust from a house chimney. About 85 per cent of the CO2 in the exhaust can be captured/removed and stored underground.

Auto thermal reforming combines CH4 with O2 inside a reactor. There can be an excess of CO2 in the syngas. 90-95 per cent of the unused CO2 can be captured and stored.

Syngas will continue to be produced in these manners as there are no emerging alternatives that produce significantly less CO2.

Some of the world is pursuing H2 as a green fuel for vehicles, power plants, etc. When H2 is burned or reacted in a fuel cell it combines with O2 producing H2O with no CO2 emissions. Ammonia is also being investigated as a green fuel as it has no CO2 emissions.

A number of countries (particularly Japan) are promoting H2 because they desire fuel options other than renewables (solar/wind) and batteries (e.g. electric vehicles). One concern is that there are increasing challenges in accessing raw materials such as copper, lithium, cobalt and nickel used in manufacturing renewables and batteries. Also, some consider H2 more suitable than batteries for powering things such as planes and cargo ships.

H2 can be produced via the high electrical consumption process of water electrolysis, which has no CO2 emissions. But to meet short term demand it will also have to be supplied from sources such as syngas with carbon capture.

Depleted oil and gas reservoirs that contained high pressure gas/oil are suitable for CO2 storage. The reservoir’s top, solid rock layer that trapped high pressure gas below ground will do the same for CO2.

Used and unused wells into CO2 storage reservoirs should be monitored for leaks. If leaks can’t be stopped then wells should be plugged.

CO2 will be transported in high pressure pipelines with the risk of rupture no greater than for natural gas pipelines. CO2 will not ignite so in this respect it is safer than natural gas.

Areas in the world that have underground CO2 storage capabilities and supplies of natural gas could become hubs for petrochemical and H2 facilities. A possibility for Medicine Hat.

CCS will reduce CO2 emissions, hasten the reduction of fossil fuels and ensure flexible green fuel options.