PDF Publication Title:
Text from PDF Page: 002Energies 2021, 14, 387 2 of 32 CO2 per unit of energy generated than other fossil fuels. It burns cleanly and efficiently, and generally requires limited processing to prepare it for end-users, with lower carbon emissions in comparison to other fuels. However, the energy density of natural gas at environmental condition (i.e., between 38.15 and 40.72 MJ/m3) is lower than that of liquid petroleum fuels, which have an energy density range of 28,000 to 42,000 MJ/m3 . As a result, the transportation and storage of gas fuel require a compression or liquefaction step to obtain the same quantity of energy over the same volume of liquid fuels. The possible solutions leading to the reduction of CO2 emissions are: (i) switching to a low carbon economy; (ii) increasing system efficiency; (iii) implementing CCS technologies to allow a gradual transition from fossil fuels to other more sustainable ones. Renewable power plants cannot provide enough base-load electricity generation, and they depend on geographical location and, therefore, on the availability of resources. Thus, CCS is a feasible solution to reduce the anthropogenic CO2 emissions in a transition phase . Thermogenic natural gas is formed when buried organic material is subjected to enormous heat and pressure over geological time. Natural gas reservoirs are categorised as conventional or unconventional gas reserves. Conventional resources of natural gas are accumulated in permeable rocks comprising of numerous pores which allow them to retain natural gas. This gas is trapped underground by impermeable rock strata. Natural gas can be extracted economically without specialised technologies, using vertical well bores . Otherwise, unconventional resources are formed in more complex geological formations (e.g., shale gas and tight gas), trapped in rocks with lower porosity and permeability than conventional reservoirs. These rocks prevent the easy flow of the gas through the pores to the standard type of well. The extraction of gas from these reservoirs requires expensive specialised techniques, such as hydraulic fracturing . NGHs are deposited both in continental sedimentary rocks, in the polar area, and marine sediments, and they form at low temperatures (≤26.85 ◦C) and moderate/high pressure (≥6 bar) . Clathrate hydrates are solid crystalline compounds in which, typically, methane, ethane, propane and carbon dioxide are trapped inside cages of water molecules. This work is part of a larger research project aims to develop an innovative techno- logical solution to enhance the extraction of subsea methane from marine NGHs. CO2 is injected in subsea NGH formations to enhance methane recovery and is eventually trapped as stable gas hydrates in a substitution process. As a result, the fuel obtained is virtually neutral in terms of GHG emissions. The replacement of CH4 with CO2 is thermodynamically favoured, and it represents a unique opportunity to recover an energy resource and to store this common greenhouse gas. Therefore, geological NGH formation can be used as an energy resource, capable of providing methane, whilst CO2 storage could contribute to reducing GHG emissions. In this paper we review the current state-of-the-art of CO2 capture, transport and storage, focusing on hydrate storage at techno-economic level. We first discuss carbon capture processes applied to the industrial and power sector (Section 2), and highlight the CO2 capture costs and performance of different power plants (Section 3). Then in Section 4 we contextualise CO2 transportation via pipeline, neglecting other means of transport because they are less used. The sequestration of CO2 is more widespread than its reuse, therefore, conventional CO2 storage (e.g., brine aquifer and depleted oil and gas) and, in particular, clathrate hydrate formation are presented in Section 5. Section 6 concludes with the cost of the complete CCS process at different distances between the CO2 source and sink, identifying one of the possible final CCS chains. 2. CO2 Capture Systems Many abatement technologies affect the use of fossil fuels or their emissions in the atmosphere (e.g., carbon capture, utilisation, and storage, use of nuclear power, replacement of coal by natural gas). CCS can be applied in power plants and industrial facilities and involves CO2 separation, compression, and transportation (via pipeline or shipping) and its storage in a geological site (e.g., saline aquifer, oil and/or gas reservoir).
PDF Image | Energies 14
PDF Search Title:Energies 14
Original File Name Searched:energies-14-00387.pdf
DIY PDF Search: Google It | Yahoo | Bing
SeaMerlin The SeaMerlin Engine is a water based gas leverage turbine for marine propulsion, seawater distillation, oceanwater CO2 harvesting, and more.
About: More about Infinity Turbine and the quest for the Xprize... More Info
Strategy and Consulting Services: Renewable energy strategy, Organic Rankine Cycle, CO2 energy, and Sonification technology consulting... More Info
@elonmusk XPrize $100 million CO2 Challenge: Carbon Removal Prize Challenge Sponsored by Elon Musk... More Info
CO2 Phase Change Demonstrator: Experiment with gas to liquids (CO2 to alcohol) using Nafion and our phase change demonstrator cart (we can ship worldwide)... More Info
CO2 GTL Gas to Liquids Experimental Platform: Experiment with gas to liquids (CO2 to alcohol) using Nafion (electrolyzer membrane) and our phase change demonstrator cart (we can ship worldwide). CO2 goes supercritical at 31 C. This is a experimental platform which you can use to demonstrate phase change with low heat. Includes integration area for small CO2 turbine, static generator, Nafion pellets, Nafion membrate, or Nafion tubes... More Info
Concept: The concept of the SeaMerlin Engine is to convert or supplement existing marine vessel propulsion to a gas leverage turbine which scavenges CO2 from saltwater at the same time it provides vessel thrust.