Carbon Sequestration and Ocean Desalination
Carbon sequestration is the lockup of carbon dioxide before or after it enters the atmosphere. Carbon dioxide is a low energy, stable byproduct of the reaction of higher energy carbon compounds. These reactions both release energy and increase the entropy of (cause the dispersal of) net carbon compounds, the most notable example the burning of fossil fuels. Thus it takes energy both to collect (re-concentrate) the carbon and to create something useful with it. All sequestration techniques, including disposal in underground injection wells, thus require energy.
The energy of a sequestration technique is commonly referred to as “the energy penalty.” We live in an age of looming energy shortage. Any discussion of an “energy penalty” usually kills the will to do anything about carbon. However there are certain industrial processes already in progress that can significantly lower the energy penalty of certain sequestration processes if the processes are combined. Below are media explaining the process, including a video, two news-formatted articles, and some further thoughts on renewable energy.
An Environmental Trifecta: The following video explains how brine from ocean desalination can be used for carbon sequestration [the lock-up of CO2 emissions] by producing carbonate mineral solids:
The presentation is also available over at SlideShare.net so that you can go through it slide by slide at your own pace. SlideShare only presents a complete slide (all information at once), with no transitions, animations, or the audio, but you can download the PowerPoint (pptx) and watch on your own computer.
An article in the Orange Juice Blog (a news outlet for Orange County, California) summarizes how the salt from ocean desalination can be used to lock up (sequester) carbon dioxide from a property-sharing, natural gas, power plant.
The “executive summary” of the technique is here:
The summary has a link to a longer version of the article that includes more technical details, as well as a discussion of how environmental mitigation is split along economic self interests, while the key is to work together.
The long form version is here:
Poseidon and AES: Don’t dump your daily 175 railroad hopper cars of salt into the ocean. Use it to lock up your daily 120 railroad hopper cars of CO2 emissions.
In the end the sequestration techniques can produce useful products to make the effort economically sustainable even without UNFCCC carbon credits.
The sections linked below discuss the importance of applying renewable energy, and the critical role water plays in all of these technologies.
The first step toward lowering your carbon footprint is to not produce carbon in the first place by using non-carbon sources of energy. Renewable Continuously-sourced energy can be readily deployed on rooftops and many other existing infrastructures. “Whether captured or not, the equivalent of 12 gallons of gasoline [of solar energy per day] falls on an 80 square meter rooftop under average insolation conditions. With currently feasible efficiencies, we can capture about two of those gallons (15%) photovoltaically, and 9 of those gallons (75%) thermally. Currently, more money is spent on shingles to protect rooftops from the damage of solar radiation than on solar panels to tap it.” —Entropy Happens, Chapter IV A 1
Why do you need water expertise on your carbon reduction project? Used in cooling and cleaning, water is critical to the development of all energy resources …
… and water is a critical resource for the electrolytic production of hydrogen. Hydrogen is an energy carrier, providing a way to store energy as a clean fuel from any energy resource, “…but with water as a source of the hydrogen, the pure water leaving a fuel-cell is derived from purified water entering an electrolyzer [a chemical electrolytic cell used for the production of hydrogen].” [Entropy Happens, Chapter III E]
- Hoaglund, J.R., C. Hochgraf, and T. Bohn, 2003. The Hydrogen Effluent. Ground Water, vol. 41, no. 4, p. 404-405.
All carbon sequestration projects–processes for the actual reduction of carbon emissions from carbon sources– are in various stages of research, development, testing, and demonstration. Carbon Negative Water Solutions is developing carbon sequestration techniques using natural water chemistry. Algae and carbonate minerals removed the CO2 from Earth’s original atmosphere. We are repeating the process industrially for today’s carbon reduction.