Researchers Develop Method to Remove Carbon from Ocean

American researchers say they have developed a method to remove carbon dioxide (CO2) from the sea and produce a clean-burning fuel in the process.

The method was created by an engineering team at the University of California, Los Angeles. The researchers say the process can be an additional way to help reduce CO2 from the environment to fight the effects of climate change.

Plants and currents in the ocean take in large amounts of CO2 from the atmosphere. The sea is estimated to have drawn¹ in about 30 percent of carbon emissions³ since the Industrial Revolution, The Associated Press reports.

This process has been a major reducer of carbon and helped protect humanity from the effects of early climate change. But carbon emissions also make oceans more acidic. This can hurt ocean structures, called coral reefs. Reef damage can then harm the growth of many kinds of sea life.

Gaurav Sant is the director of UCLA's Institute for Carbon Management and helped lead the development project. He told the AP that the technology, called SeaChange, is meant to use the ocean's natural abilities to reduce carbon levels in the sea.

The process sends an electrical charge through seawater flowing through tanks on a large boat. That sets off a series of chemical reactions that turn the carbon emissions into a solid mineral that includes calcium⁴ carbonate, the same material seashells are made of. The seawater is then returned to the ocean and can pull more carbon dioxide out of the air. The calcium carbonate settles to the sea floor.

The process has already been demonstrated in California. Researchers are working on plans to begin another project in Singapore. The two projects are expected to be fully⁵ operational by 2025. Researchers say they are expected to remove thousands of tons of CO2 per year. If successful, Sant said the plan is to build additional centers to remove millions of tons of carbon each year.

But experts say even if that amount of carbon can be removed, that is still thousands of times less than what will be needed to effectively reduce climate change.

Margaret Leinen is the director of Scripps Institution of Oceanography, an ocean research center in San Diego, California. She told the AP that while the process likely will be effective, she questions how much effect it will have on climate change over a long period.

Sant said an estimated 10 billion metric tons of carbon will need to be removed from the air each year beginning in 2050. He added that the success of such technology will depend on "how fast you can build (the centers) out."

The UCLA team says at least 1,800 industrial-sized centers would need to capture 10 billion tons of atmospheric⁶ carbon dioxide per year. But even smaller amounts could still make a difference.

Researchers from the UCLA Samueli School of Engineering built the demonstration⁷ system in two years. The project has received tens of millions of dollars from the U.S. Department of Energy and from private supporters.

Much of the attention on carbon-reducing measures has traditionally been on land-based projects, such as planting trees or building factories to capture carbon from polluters. But those processes have limitations. Scientists have increasingly turned to help from the ocean, which covers 70 percent of the Earth's surface.

One way the process is different is that it produces hydrogen. Hydrogen is considered a clean-burning fuel that can be used to power vehicles, airplanes, homes and more. To remove one metric ton of carbon dioxide, about 220 metric tons of water needs to flow through the system. Sant said that produces about 35 kilograms of hydrogen.

Sant launched the startup company Equatic to expand the project. The company's aim is to remove carbon at a cost well below $100 a metric ton. The hydrogen would be produced at less than $1 per kilogram. That is much less than the current cost of cleanly produced hydrogen.

Words in This Story

current – n. the natural flow or air or water in one direction

emission² – n. the act of sending out gas, heat, light, etc.

1 drawn   

v.拖，拉，拔出；adj.憔悴的，紧张的

参考例句：

• All the characters in the story are drawn from life.故事中的所有人物都取材于生活。
• Her gaze was drawn irresistibly to the scene outside.她的目光禁不住被外面的风景所吸引。

2 emission   

n.发出物，散发物；发出，散发

参考例句：

• Rigorous measures will be taken to reduce the total pollutant emission.采取严格有力措施，降低污染物排放总量。
• Finally,the way to effectively control particulate emission is pointed out.最后，指出有效降低颗粒排放的方向。

3 emissions   

排放物( emission的名词复数 )； 散发物（尤指气体）

参考例句：

• Most scientists accept that climate change is linked to carbon emissions. 大多数科学家都相信气候变化与排放的含碳气体有关。
• Dangerous emissions radiate from plutonium. 危险的辐射物从钚放散出来。

4 calcium   

n.钙(化学符号Ca)

参考例句：

• We need calcium to make bones.我们需要钙来壮骨。
• Calcium is found most abundantly in milk.奶含钙最丰富。

5 fully   

adv.完全地，全部地，彻底地；充分地

参考例句：

• The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气，然后全部呼出。
• They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。

6 atmospheric   

adj.大气的，空气的；大气层的；大气所引起的

参考例句：

• Sea surface temperatures and atmospheric circulation are strongly coupled.海洋表面温度与大气环流是密切相关的。
• Clouds return radiant energy to the surface primarily via the atmospheric window.云主要通过大气窗区向地表辐射能量。

7 demonstration   

n.表明，示范，论证，示威

参考例句：

• His new book is a demonstration of his patriotism.他写的新书是他的爱国精神的证明。
• He gave a demonstration of the new technique then and there.他当场表演了这种新的操作方法。