"The discussion of energy consumption for cryogenic & combined #DirectAirCapture systems is explored in the newly published thesis."ποΈ
Details are discussed in aπ§΅β¬οΈ
1/10
In this novel approach, "a thermodynamic model was constructed using psychometric theories to model the #desublimation of CO2 in a #DAC system. The system was modeled
to include a precooling heat exchanger & a deposition chamber where the desublimation
of CO2 occurs."
2/10
3οΈβ£ base systems studied:
πΈ NC (no precompression/turbine recovery)
πΈPC (precompression only)
πΈTR (precompression & turbine recovery)
at 3οΈβ£ different compression ratios, n=400, 800 & 2000.
Then, a combination #DAC system, PSA, was modeled."
3/10
"A dual-column, 4οΈβ£-step Skarstrom Cycle PSA (pressure swing adsorption & cryogenic distillation) unit was analyzed using Extended Langmuir Models & the
ideal gas law to simulate a CO2 conc. prior to the deposition chamber. The NC & PSA systems were assessed at Tamb= -50β¦C."
4/10
This study finds that "while increasing the compression ratio of the system, there is no net energy benefit when capturing CO2 given the current state-of-the-art in commercial compressor & #cryocooler capabilities."
5/10
"The assessment of the efficiency of a precooler versus TR finds that it is more advantageous to utilize a heat exchanger precooler than precompression with turbine recovery in a #DAC system. Combining DAC systems may yield a more efficient system."
6/10
"PSA combined with cryogenic capture is less energy intensive than cryogenic capture alone. In a combined #DAC system with PSA and cryogenic distillation,
the PSA unit has a significantly lower energy consumption than the #cryocooler."
7/10
"Increasing the concentration of CO2 entering the deposition chamber significantly decreases the required energy consumption of the #cryocooler."
8/10
Read the complete #Doctoral#Thesis entitled: "Atmospheric Carbon Capture: A Review on Current Technologies and Analysis of Energy Consumption for Various Direct Air Capture (DAC) Systems" here β¬οΈ commons.erau.edu/edt/728/
π¨ The Royal Society has published a new briefing today finding that techniques to reflect a small portion of sunlight back into space (#SRM) could help lower global temperatures if deployed worldwide, but cannot replace emissions cuts or fully address climate impacts.
π§΅1/7
2/ β The report reviews solar radiation modification (#SRM) approaches, including stratospheric aerosol injection (#SAI) and marine cloud brightening (#MCB), outlining their potential to temporarily reduce warming and associated risks.
3/ β It notes that SRM would only mask the effects of GHG emissions and would not address issues such as ocean acidification.
π¨π² New research reveals that even intact boreal forests, some of the planetβs strongest natural carbon sinks, lose their ability to absorb COβ as they age.
Hereβs what the scientists found & why it matters for our climate modelsπ§΅1/9 #CarbonSink #CarbonRemoval
2/ Boreal forests cover vast regions across Canada, Russia, and Scandinavia and store enormous amounts of carbon in trees and soil.
Theyβre often seen as stable, long-term carbon sinks, but this study challenges that assumption with new global-scale data.
3/ Using seven global Net Ecosystem Productivity (NEP) datasets and a high-resolution forest age map, researchers tracked how C uptake changes as forests grow older.
They used a space-for-time substitution method, comparing forests of different ages to infer long-term trends.
π¨A major 6-country survey (N=5,310) finds Europeans support -ve emissions to meet climate goals, but strongly prefer nature-based solutions like afforestation over engineered options like Direct Air Capture. Trust hinges on benefits for nature & future generations.
π§΅1/10 #CDR
2/ When allocating how to tackle emissions, respondents clearly prioritized immediate mitigation:
π¨A new study warns that efforts to cool the planet through stratospheric aerosol injection (#SAI) could face far greater challenges than models predict, from unpredictable monsoon shifts to material shortages & engineering limits, every step adds new risks.
π§΅1/8 #SRM
2/ The authors explore both micro-level (engineering) and macro-level (governance & supply) factors that could restrict feasible deployment.
Key finding: these constraints could drastically raise costs, risks, and uncertainty, especially for βsolidβ (non-sulfate) aerosols.
3/ Traditional SAI uses sulfate aerosols (like volcanoes).
But alternatives, CaCOβ, TiOβ, AlβOβ, ZrOβ, even diamond, promise less ozone damage.
Yet producing, aerosolizing, and dispersing these solids in submicron form is technically daunting.
π¨Scientists built a device that captures carbon from the seawater and turns it into biodegradable plastic, using bacteria as a living bioreactor.
#CDR #mCDR #CarbonDioxideRemoval #Bioplastics
DETAILSπ§΅1/8
2/ The system comprises 3 components:
1οΈβ£ C extraction
Traditional seawater electrolysis systems often fail within hours due to mineral buildup
To solve this, researchers designed a solid-state electrolysis unit that isolates sensitive ions using membranes & a solid electrolyte
3/ The modified design acidifies H2O, converting dissolved C (mainly bicarbonate & carbonate ions) into COβ gas for collection.
The prototype operated continuously for 22 days, processing 177 liters of seawater & extracting 6.54L of COβ, with an energy use of 3 kWh/kg of COβ.