We have thoroughly documented that Carbon Dioxide can, on a practical basis, be reclaimed, even from the atmosphere itself, and then be productively recycled in the synthesis of valuable products, including liquid and gaseous hydrocarbon fuels.
We have also noted that some processes for the conversion of Coal into liquid and gaseous hydrocarbons generate some incidental Carbon Dioxide, which, as we have also previously documented, can, in processes of Indirect Coal Liquefaction (ICL), be reclaimed and recycled into the Coal conversion process, and thereby made to enhance and increase the production of valuable hydrocarbon synthesis gas, "syngas".
Herein, from the world leader in Coal conversion technology, South Africa, we submit further documentation of that fact, as inventors we believe to be associated both with South Africa Synthetic Oil Limited, SASOL, and with the University of Witwatersrand, explain that, not only can Carbon Dioxide be recycled into the synthetic fuel production process; but, energy requirements for that process can, at the same time, thus be reduced and further Carbon economies consequently achieved.
Comment follows excerpts from:
"US Patent Application No. US2009/0317669A1 - Carbon Efficiencies in Hydrocarbon Production
Abstract: This invention relates to a method of producing liquid hydrocarbons, preferably internal combustion engine fuels, using feedstocks of coal or methane. Depending on the nature of the feedstock it is subjected to a gasification and/or water gas shift process which produces a syngas that is rich in carbon dioxide and hydrogen rather than carbon monoxide and hydrogen as in the conventional process. The carbon dioxide and hydrogen are combined in a Fischer Tropsch process to produce desired hydrocarbons and water. The energy requirements of the gasification/reforming process to produce a syngas that is rich in carbon dioxide and hydrogen is considerably less than the energy requirements for gasification/reforming process for producing the conventional carbon monoxide rich syngas. This reduction in energy consumption reduces considerably the quantities of carbon dioxide releases into the atmosphere compared to conventional processes that are based on carbon monoxide rich syngas. Un-reacted CO2-rich syngas can be recirculated or can also be used, in molten carbonate fuel cells, or to generate energy or steam in turbine processes ... .
Field: This invention relates to improvements of carbon efficiencies, and reduction of carbon dioxide emissions in hydrocarbons produced by a Fischer-Tropsch process.
Background: The Fischer-Tropsch process is used primarily to convert carbon monoxide and hydrogen, also known as "syngas", into liquid hydrocarbons for use as fuel.
Gasifier feedstocks are usually coal or methane gas.
Where coal is used as the feedstock it is, initially, converted to carbon monoxide (CO) and hydrogen gas (H2) by the following gasification process: C + H2O = CO + H2.
The carbon monoxide is then partially converted to carbon dioxide (CO2) and hydrogen (H2) by the following water gas shift process: CO + H2O = CO2 + H2.
The water gas shift process is controlled so as to provide the required CO:H2 molar ratio (for Fischer-Tropsch
synthesis). ... The CO2 produced in this way ... leads to carbon inefficiencies.
Where methane is used as the feed the reforming process is used: CH4 + H2O = CO + 3H2.
As in the case of the coal fed process the water gas shift process partially converts the carbon monoxide to carbon dioxide so as to provide the required CO:H2 molar ratio ... for the Fischer-Tropsch process. The carbon dioxide created in this way is emitted by the process.
As indicated above, the CO and H2 gas combination is termed "syngas" and it can be used to produce a wide range of carbon based chemicals perhaps the most important of which is fuel for internal combustion engines.
The (excess) CO2 is utilized (herein) as a reactant and is converted into the desired product.
It is an object of this invention to provide an improvement of carbon efficiencies in hydrocarbon production with a consequent reduction of carbon dioxide emission.
Summary: In accordance with this invention there is provided a process for producing hydrocarbons from a CO2-rich syngas ... comprising reacting the CO2-rich syngas in a Fischer-Tropsch process to produce hydrocarbons ... .
There is also provided for a water gas shift process to be used, where necessary, to modify the CO2-rich syngas and achieve a desired CO2 concentration.
There is also provided for CO in the CO2-rich syngas to be used to produce hydrocarbons ... .
There is further provided for syngas to be produced by combination gasifier and reforming processes where more than one feedstock, preferably coal and natural gas or methane is used ... .
There is further provided for the methane to be ... produced by microbial degradation of waste products.
There is further provided for ... CO2 to be used ... to form hydrocarbon compounds ... ."
----------
We'll close our already over-long excerpts with some reminders:
Any needed Methane, which can be, as herein, converted with Coal, through reactions with Steam, into hydrocarbon syngas, can, as we've thoroughly documented, itself be generated, in addition the activity of microbes on carbon-recycling "waste products", via the Nobel-winning Sabatier process now being further refined by NASA, all as we have previously documented, directly from Carbon Dioxide.
Therein lie further routes for the recycling of Carbon Dioxide which can be extracted directly from the environment; and, those would be in addition to the microbial breakdown of carbon-recycling organic wastes, as specified above, to produce Methane.
Moreover, note that CO2 can be directly used in this process "to form hydrocarbon compounds".
Finally, though not reflected in our excerpts, the full Disclosure reveals, in confirmation of documentation we've earlier provided, that heat energy, generated during some exothermic stages of the total Coal conversion reaction sequence, can be harvested and redirected back into the process, thus reducing potential CO2 generation from outside sources of energy that might otherwise be required.
