Direct Air Capture & Sequestration

The diagram above shows, based on the laws of thermodynamics, the minimum energy to remove CO2 from ambient air (Direct air capture). Removal requires about 3 times as much energy as the energy gained by burning coal and more than twice as much as from burning natural gas. That is primarily because the CO2 is so dilute in the atmosphere. For net CO2 removal with DAC, cheap energy (solar and wind, perhaps also small modular nuclear) is needed.

However, the diagram above assumes energy use for fans to speed up air circulation across a catalyst that captures CO2 (there are many possible catalysts.) Is also assumes that heat is later used to separate the CO2 from the catalyst, so that the capture process can begin anew and so that the purified CO2 can be pumped to its final resting place (or another use).

Moreover, it concentrates on heat-based approaches. Other approaches - including electric charge, pH change, humidity, and phase change - are gaining traction in the 2020s. See diagrams a little further down the page. These approaches are generally less energy intensive.

Air Capture

Can We Engineer Our Way Out of the Climate Crisis with Carbon Capture? 0324.rtfA New Carbon Removal Startup Is Powered by Sunlight and Seawater 0224.rtf

Will Direct Air Capture Ever Be Affordable? The Rise of DAC 3.0 - 0224.rtf

Articles

Microsoft Inks Record Carbon Removal Deals as Emissions Rise 0625.rtfMIT Breakthrough Makes Carbon Capture 6x More Efficient 0525.rtfBig Bets on Speculative Carbon Capture Tech Ignore Today’s Solutions 0425.rtfOccidental Gets Record Carbon-Removal Deal with Mega-Buyer Microsoft 0724.rtfCarbon Removal’s Holy Grail Cost Cut Is Further Away than It Seems 0624.rtfSwiss Geo-Engineering Start-Up Targets Methane Removal 0624.rtfHow New ‘World’s Largest’ Vacuum to Suck CO2 from the Air Works 0524.rtfCan We Engineer Our Way Out of the Climate Crisis with Carbon Capture? 0324.rtfStartup Is Building a Plant to Zap Seawater, Grab CO2, and Produce Hydrogen - 0224.rtfA New Carbon Removal Startup Is Powered by Sunlight and Seawater 0224.rtfWill Direct Air Capture Ever Be Affordable? The Rise of DAC 3.0 - 0224.rtfAmazon Bets Big on Oil Giant Occidental’s Carbon Removal Project 0923.rtfHow an Oil Giant Took Control of Biden's Billion-Dollar Bet on Carbon Capture 0823.rtfCan Vacuums Slow Global Warming? Administration Bets $1.2 Billion on It. 0823.rtf - Much more progress on capture from high-density CO2 streams (100% at ethanol plants, ~15% at industrial plants, than 0.042% in ordinary airClick for more

What’s Needed to Reach Net-Zero This Century - IEA 0423.rtfCarbon-Sucking Tech Could Need More Energy than All Homes Use 0323.rtfHow to Suck Up CO2, Turn It into Baking Soda, and Store It in the Oceans 0323.rtfArtificial Trees 0223.rtfCarbon Removal Is Where Green Investment Should Go 0123.rtfCompetition Heats Up for U.S. Direct Air Capture Program 0123.rtfCO2 Removal Efforts Seen Far behind What Is Needed 0123.rtfNew York Landlords Try Carbon-Sucking Towers to Comply with Climate Law 0123.rtfNasdaq Targets Boom in Market for Carbon Removal in Coming Years 1022.rtfWhy the $100 per Ton Target for Carbon Removal May Be ‘Pure Fantasy' 1022.rtfAudi and Krajete Filter CO2 Out of the Air 1022.rtf3 Big Direct Carbon Capture Deals to Know 1022.rtfCalpine & Blue Planet Transform Captured Carbon into High-Grade Limestone 0922.rtfNew Law Helps U.S. Firm Launch Wyoming Direct Air Carbon Capture Project 0922.rtfWhat the Inflation Reduction Act Means for Direct Air Capture 0822.rtfThe Chips Act Has a CO2 Removal Easter Egg 0822.rtf - $1 billion for carbon removal researchClimeworks Predicts CO2 Removal Cost Drop to Below $250 : Tonne by 2030 - 0722.rtfStartup That Sucks CO2 from the Air Is Building a Big Plant in Iceland 0622.rtfCan Carbon Capture Be Part of the Climate Solution? 0622.rtfCarbon-Removal Industry Draws Billions to Fight Climate Change 0622.rtfU.S. Steel Backs Snatching CO2 from the Air and Storing It in Concrete 0622.rtfFastest CO2 Catcher Heralds New Age for Direct Air Capture 0522.rtfMicrosoft, Salesforce Add $300 Million to Carbon Removal’s Growing Cash Pile 0522.rtfWhitehouse, Coons Introduce Act to Accelerate CO2 Removal 0522.rtfTonko, Peters Introduce CO2 Removal Legislation 0422.rtfMusk and Google Add to $2 Billion Boost for Carbon Removal 0522.rtfThere Has Never Been a Better Time to Start a Carbon Removal Company 0422.rtfWe Need a Massive Carbon Removal Industry. What Will It Take to Scale It Up? 0422.rtfDirect Air Capture 0422.rtfA Scalable Direct Air Capture Process Based on Weathering Calcium Hydroxide 0322.rtf - Heirloom explains its process. Several pages, with chemical equations.Climeworks Raises $650 Million in Largest Round for Carbon Removal Startup 0422.rtf - overview of DAC methods, EF. Heirloom is projected to hit $50 / ton for carbon removal by 2035. It gets rid of the other ~1/2 of energy use: moving air past the catalyst. Use natural air circulation (slower) instead of fans.Carbon-Capture Startup Using Dirt Cheap Material Raises $53 Million 0322.rtf - Limestone to calcium oxide and backFuel Cells and Game-Changing Tech to Remove 99% of CO2 from Air 0222.rtfBill Gates Invests in Carbon Capture Startup After Tech Breakthrough 0222.rtfThe Market & Policy Landscape for Advancing Direct Air Capture – Who Pays? 0122.rtfAs Carbon Emissions Rise Unabated, Scientists Eye a Methane Removal Fix 1121.rtf“Urban Sequoia” Technology Could Turn Buildings into Climate-Fighting Tools 1121.rtf - Stack or chimney effect draws airTo Slow Global Warming, Some Researchers Want to Pull Methane Out of the Air 1121.rtfThe Dream of Carbon Air Capture Edges Toward Reality 0821.rtf - Movement has begun from $500-600 per ton of CO2 removed to $94-232. Discussion of the industry.Direct Air Capture Carbon Removal Technology Reaches Early Milestone 0921.rtfThese ‘Super-Trees’ Are Engineered to Capture More Carbon 0621.rtfDirect Air Capture of CO2 Is Suddenly a Carbon Offset Option 0321.rtfMicrosoft Climate Fund Backs Climeworks Effort to Suck Up Carbon 0121.rtfOpenAir’s R&D Roundup – Violet and Cyan Home CO2 Removal Projects 0121.rtfChevron Invests in Carbon Capture and Utilization Startup Blue Planet 0121.rtf - store CO2 in calcium carbonate aggregate for concreteWill Machines That Scrub CO2 from the Air Halt Climate Change? 0121.rtf - brief overview: Climeworks, Carbon EngineeringBusinesses Aim to Pull Greenhouse Gases from the Air 0121.rtf - many companies. Mostly about CCS and DAC.Researchers Unveil New Method for Converting CO2 into Jet Fuel 1220.rtfMining the Sky for CO2 with Metal Trees, Towers and Pumps 0121.rtfClimeworks to Build World’s Biggest Climate-Positive Direct Air Capture Plant 0920.rtfRemoving CO2 Could Spark Big Rise in Food Prices 0820.rtf - Liquid sorbent DAC systems require lots of water and heat. However, solid sorbent systems require no fresh water (or burning natural gas). So, lack of water to grow food probably will not be exacerbated by DAC - using solid sorbents.Swiss Carbon Capture Startup Raises $76 Million in Funding Round 0620.rtfGuide to Negative Emissions Technologies - Focus on Direct Air Capture 0320.rtfNew Industry Develops around Sucking CO2 Out of the Atmosphere 1219.rtfWhy Carbon Capture Hasn’t Saved Us from Climate Change Yet 1019.rtfMIT Engineers Develop a New Way to Remove CO2 from Air 1019.rtfReverse Engineering the Climate Crisis Is Not Only Possible—It's Necessary 1019.rtfThe Future of Carbon Capture - Old Idea to Fight Climate Change Gets New Look 1019.rtfCarbon Engineering to Double Capacity at Its Direct Air Capture Plant 0919.rtfPulling CO2 Out of the Air and Using It Could Be a Trillion-Dollar Business 0919.rtfPowerful ‘Mechanical Trees’ Can Remove CO2 from Air at Scale 0419.rtfCO2 Solutions Commissions Its 1st Commercial Carbon Capture Unit 0419.rtfCO2 Removal Factories Slowly Gain Ground 0419.rtfBillionaires Back Carbon Engineering to Build 1st ‘Negative Emissions’ Plant 0319.rtf - take 1New Facility Aims to Capture 40 Million Trees’ Worth of CO2 Every Year 0319.rtf - take 2BHP Invests US$6 Million in Emissions Reduction Company, Carbon Engineering 0319.rtf - take 3One Man’s 2-Decade Quest to Suck Greenhouse Gas Out of the Sky 0219.rtfOil Industry Makes Landmark Investment in CO2 Air Capture 0119.rtfHow One Company Pulls Carbon from the Air, to Avert Climate Catastrophe 1218.rtfCan 12 Billion Tonnes of Carbon Be Sucked from the Air? 1118.rtfCould Oil Nation Norway Help Save the Climate? 1018.rtfThis Gel Grows and Heals by Gobbling Carbon from the Air 1018.rtfCould Carbon-Capture Technology Be a Silver Bullet to Stop Climate Change? 1018.rtfCarbon Removal Firms See Opportunity in U.N. Climate Report 1018.rtfClimeworks Opens a 3rd Plant Capturing CO2 from the Air 1018.rtfHuge Fans, Burning Biomass May Help Store Carbon for Climate Fight 0918.rtfMoniz Group Launches ‘Substantial' CO2 Air Capture Project 0918.rtfSucking Carbon from Air, Swiss Firm Wins New Funds for Climate Fix 0818.rtfPioneers of CO2 Removal See Boon for Renewables 0418.rtfSaving the World with CO2 Removal 0118.rtfCan CO2 Removal Save the World? 1117.rtfWorld’s 1st “Negative Emission” Plant Will Turn CO2 to Stone 1017.rtfCarbon-Sucking Technology Needed by 2030s, Scientists Warn 1017.rtfHealthy Climate News – 7 Technologies That Could Scale 0317.rtf - 3 are Direct Air Capture.It’s Time to Start Talking about “Negative” CO2 Emissions 0817.rtfSwiss Firm Climeworks Starts Sucking CO2 from the Air, to Fight Climate Change 0617.rtfFocus on Carbon Removal a ‘High-Stakes Gamble’ 0517.rtfA Cheaper Way to Pull CO2 from the Air, Turn It into Crystals 0117.rtf - Guanidine, lower temp outgassing than amines.Report from Global Thermostat Tour 1216.rtf - Blow air thru 6-inch cubes. They use amines in ceramic honeycomb to capture CO2, heat to 80°C to release it for disposal. Capture 1 ton of CO2 / year. $70 / ton now, projected fall to $20 / ton. [Use billions of such cubes.]Trapping Carbon Works, but High Cost to Limit Its Use to Essential Processes 1116.rtfCould Mutant Plants Save Us from Global Warming? 1116.rtfScientists Accidentally Discover Efficient Process to Turn CO2 Into Ethanol 1016.rtfArtificial Leaf Turns CO2 Emissions Into Fuel 0816.rtfWhy CO2 'Air Capture' Could Be Key to Slowing Global Warming 0516.rtfCan Pulling Carbon from Air Make a Difference on Climate? 1215.rtfIs the 2°C World a Fantasy? 1115.rtfCould Diesel Made from Air Help Tackle Climate Change? 0915.rtfNanoscale Carbon Capture Strategy Pays Off 0815.rtfStartups Have Learned to Remove Carbon from the Air. Will Anyone Pay Them? 0715.rtfPragmatic Ways to Capture Carbon from Ambient Air & Smokestacks 0615.rtfDoes Air Capture Constitute a Viable Backstop Against a Bad CO2 Trip? 1213.rtfCarbon Capture and Renewable Energy Generation by Pyrolysis 0913.rtfCarbon Capture from Air Needed to Fight Climate Change 0813.rtfChemical Plant Would Turn Emissions into Useful Products 0813.rtfWay to Remove CO2 from the Air 0613.rtfUS Lab Removes CO2 from Air at Low Cost 0513.rtfSuck Carbon Emissions Right Out of the Air 0413.rtfScrubbing CO2 from Air for Centuries 0710.rtfPulling CO2 Out of Thin Air 0113.rtfNew Holey Material Soaks Up CO2 0612.rtfCheap Material Can Scrub CO2 from Air 0112.rtfCCS No Remedy For Warming 0410.rtfCanada Lab Hopes to Turn Emissions into Algae 0513.rtf

What the Inflation Reduction Act Means for Direct Air Capture 0822.rtf

The tax credit awarded companies for CO2 captured and durably stored was raised from $50 to $180 per tonne. For CO2 captured and utilized (concrete, carbonation, oil extraction, etc.), the increase was from $35 to $130 per tonne. Minimum capture to claim the credits is reduced to 1000 tonnes / year. Smaller projects can receive direct pay for the full value of the credits for the projects 1st 5 years. Also, the deadline to build eligibale facilities ws extended 7 years. The Act also provides $2.15 billion for low-carbon buildings and use of low-carbon materials. This benefits companies such as CarbonCure and CarbonBuilt,which incorporate captured CO2 into building materials.

We Need a Massive Carbon Removal Industry. What Will It Take to Scale It Up? 0422.rtf

Verdox has a process that uses electric charge changes instead of heat to separate captured CO2 from the catalyst and regenerate the catalyst sorbent or solvent. Using electric charge changes gets rid of ~ 1/2 of energy use. $40-80 / ton by 2035?

Direct Air Capture Carbon Removal Technology Reaches Early Milestone 0921.rtf

- Climeworks’ Orca plant opens.

Guide to Negative Emissions Technologies - Focus on Direct Air Capture 0320.rtf

Sequestering Carbon in Rocks - Lackner 2002.pdf - 42 pp

from Abstract: "Sequestration of waste carbon dioxide will require methods that can safely store several trillion tons of carbon dioxide. Long-term storage of a gaseous substance is fraught with uncertainty and hazards, but carbonate chemistry offers permanent solutions to the disposal problem. Carbonates can be formed from carbon dioxide and metal oxides in reactions that are thermodynamically favored and exothermic, which result in materials that can be safely and permanently kept out of the active carbon stocks in the environment. Carbonate sequestration methods require the development of an extractive minerals industry that provides the base ions for neutralizing carbonic acid."

Among many topics addressed are alkalinity, magnesium carbonates, molten salts, serpentine and olivine.