Making friends with our climate change adversary

Carbon dioxide (CO₂) moves silently between our air, land, plants, animals, and people. Without CO₂, natural life on Earth would not survive.

Global industrialization has dramatically increased greenhouse gases emitted into our atmosphere, and CO₂, our life-sustaining friend, has also become our climate change adversary.

Carbon capture, utilization and storage (CCUS) is widely regarded as one of the primary ways toward managing the world’s excessive CO₂ emissions.

CCUS captures CO₂ at the source, and then compresses it.

After the CO₂ is shrunk, it can be transported for long-term underground storage, or it can be recycled into a useful purpose by turning it into marketable industrial and commercial products. 

Standing above the world’s largest discovered conventional onshore oil field, Ghawar, Hawiyah NGL plant operator Omar N. Almodrhim is four hours into his 8-hour day shift. 

In front of him is the compressor for the Middle East’s most advanced large-scale CO₂ capture and reinjection project. 

Holding a clipboard, he diligently focuses on checking the machine’s 10 temperature gauges, carefully jotting down the readings. This is the second of four CO₂ compressor checks he completes each shift.

Omar, who joined the Hawiyah NGL plant in 2012, witnessed the CO₂ project’s construction in 2015, and the world’s rapid growing interest in it. 

“The project provides better protection for the environment,” says Almodrhim. “Instead of routing CO₂ to the thermal oxidizer, we put it back where it came from.”

“We have the capability to capture and process 45 million standard cubic feet of CO₂ every day.”

CAPTION FOR TOP PHOTOGRAPH
Operator Omar N. Almodrhim works with Aramco’s CO₂ capture and reinjection project at the Hawiyah NGL recovery plant, where CO₂  has been returned underground since 2015.

In standard temperature and pressure, CO₂ is a colorless gas, and compressing it transforms into a supercritical state.

After separating the CO₂ from the gas, a Hawiyah internally geared compressor uses seven stages to compress the CO₂. 

At the fifth stage, the CO₂ is routed to a gas dehydration unit, before being returned to the compressor for stages six and seven. 

The final stage compresses the gas between 1,500 psi to 1,600 psi, then pipes it 85 kilometers in an 8-inch steel alloy pipeline to the ‘Uthmaniyah gas-oil separation plant 7, where a custom-built reinjection facility safely reinjects the CO₂ back into the Ghawar oil field.

A sizable portion of the CO₂ remains sequestered, while the remaining unlocks residual oil in the reservoir — a better option for enhanced oil recovery than water.