Decarbonisation Technology - November 2021

Nitrogen

Flue gas to FGD/SCR/CCS as required

Superheated steam

Heater

Air separation unit

Air

High pressure steam

Oxygen

Natural gas + hydrogen

Fired heater

ATR

Dry syngas

Catalyst bed

Final cooling & separation

Raw syngas

Steam Fuel Air

Condensate

Waste heat boiler

Boiler feed water

ATR process flow sheet for syngas production

might find additional application as a soil improver in agriculture. The use of biochar and wood acid (produced in a sustainable way from gasification or pyrolysis of wood) as alternatives or supplements to conventional fertilizers in rice paddies is reported to reduce N 2 O emissions by more than 50%. As an additional benefit, methane emissions are reduced by more than 30%. Additional research in these areas and subsequent education and roll- out of such programmes to change agricultural practices is an area the international community can focus on at COP26 and other forums for climate change prevention. Direct air capture of CO 2 and methane CO 2 accumulation in the atmosphere has been through industrial and human activity. CO 2 removal is mainly through biological

photosynthesis in plants, where the CO 2 is converted to starchy hydrocarbons. Various mechanical direct air capture (DAC) processes have been developed to simulate the action of plants and remove CO 2 from the air. A DAC facility rated at 1 million tonnes of CO 2 capture per year does the equivalent work of 40 million trees. With such huge potential, it is no surprise that a massive amount of development activity has taken place to research, scale up, and commercialise these technologies in the past decade. One of the attractions of DAC is that CO 2 can be recovered close to where it is required for EOR. The use of DAC to remove CO 2 from the air can also be used to offset CO 2 emissions from certain aspects of oil and gas processing that are very difficult to decarbonise. For example, amine wash CO 2 recovery systems operate most cost-effectively at up to 96% of CO 2 removal from the flue gas. The

CO depleted air

Air

Gas flow channel Ferrocene electrode

CO depleted air

Air Air Air

CO depleted air

Air

Spray tower

Gas flow channel Quinone electrode

CO depleted air

Air

CO rich solution

Climeworks

Verdox

Carbyon

Carbon engineering

A selection of technologies for direct capture of CO 2 from air (DAC)