Energy Citations Database (ECD) - - Document #932888
Herein, we see that our USDOE hired the University of Georgia to demonstrate that Carbon Dioxide, reclaimed from whatever source, can, both directly and, as we will explain, indirectly, be recycled into basic chemical manufacturing industry raw materials.
The specific product of the CO2-recycling technology developed in Georgia, "succinic acid", might not even sound familiar to our readers, but, as a foreword, here's a reference that might help to explain it:
Succinic Acid - The Chemical Company: "This four carbon dicarboxylic acid has uses in a number of industries including polymers (clothing fibres), food, surfactants and detergents, flavours and fragrances and as a starting material for any number of chemicals ... . Succinic Acid has many uses in the pharma industry.
The estimated 2010 worldwide use of Succinic Acid is around 20,000 to 30,000 tonnes per year and this is on the increase by around 10 per cent a year."
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So, even though the current total demand for Succinic Acid might not, in the grand scheme of things, be that significant, that demand is growing at a significant rate.
And, the University of Georgia might enable it's usage and demand to grow even faster, by helping to commercialize the technology they developed, under contract to our United States Department of Energy, wherein Succinic Acid can be synthesized from Carbon Dioxide.
Furthermore, although we won't further emphasize it, outside of the excerpts, the biological CO2-recycling process involved herein is not photosynthesis.
It would work well in the dark confines of any industrial processing facility placed anywhere in the cloudy environs of US Coal Country.
Expensive sunlight gathering and transmission devices are not needed.
Comment, with additional references and further explanation of how the indirect CO2-recycling nature of the process can be amplified, follows excerpts from the initial and following links in this dispatch to:
Document: View Document or Access Individual Pages; DOI:10.2172/932888
"Process Design for the Biocatalysis of Value-Added Chemicals from Carbon Dioxide
Final Technical Report; July 31, 2007; Sponsor: USDOE; Contract Number: DE-FG26-04NT42126
Principal Author: Mark A. Eiteman; Research Organization: University of Georgia
Abstract: This report describes results toward developing a process to sequester CO2 centered on ... the use of bacteria to convert CO2 and glucose as a co-substrate and generates succinic acid as a commodity chemical product. The study reports on strain development and process development. In the area of strain development, knockouts in genes which divert carbon from the enzymatic steps involved in CO2 consumption were completed, and were shown not to affect significantly the rate of CO2 sequestration and succinic acid generation. ... In the area of process development, an optimal medium, pH and base counterion were obtained, leading to a sequestration rate as (specified)
(The) presence of 'toxic' compounds in the gas, including NO2, CO and SO2 did not have a detrimental effect on sequestration. (Emphasis added.)
Some results on prolonging the rate of sequestration indicate that enzyme activities decrease with time, suggesting methods to prolong enzyme activity may benefit the overall process.
Introduction: Most research on the microbial sequestration of CO2 has centered on archaea ... in liquid suspension reactor systems ... .Many of these microbial species require a photosynthetic reaction to generate ATP for subsequent CO2 fixation, which severely limits their application for CO2 sequestration due to scale-up problems, including the requirement for an extremely large reactor size. In addition, many of the organisms proposed for CO2 fixation have fastidious growth requirements, and have unacceptably low product yields and formation rates, both of which essentially eliminate industrial applications.
CO2 is a gaseous substrate, and little research has centered on advanced reactor design configurations that significantly improve CO2 utilization and continuously generate products of interest. In fact, a review of the literature shows no reports on the use of bacterial systems for CO2 fixation in bioreactors; most of the research has centered on the use of microalgal systems that require light/dark cycles and reactors with large footprints.
These microalgal reactors typically have extremely slow substrate consumption rates ... .
Substrate consumption and product formation rates are generally more than 100-fold greater in commercially relevant microbial based systems.
The general approach used in this project involves the biological incorporation of CO2 into the backbone of another inexpensive organic compound ... .
The chemical product that will be the focus of this project is succinic acid.
Cost analysis suggests that commercialization of succinic acid production by a biological route is feasible with improvements in strain and process design, and current economic models do not include benefits derived from carbon sequestration.
(In other words, we could deduct the unproductive, though mandated, expenses of Cap & Trade taxation and Geologic Sequestration in leaky old oil wells from the production cost of CO2-bases Succinic Acid.)
Succinic acid would be used as a chemical feedstock for industrial chemicals such as polymers.
As the cost for the chemical route increases in the coming years while improvements in the biological process are attained, a biological route will likely become the preferred route (of Succinic Acid manufacture).
The approach used in this research will furthermore be quite applicable to other biological processes which sequester CO2, and we hope that other promising routes involving the use of CO2 directly in the synthesis of organic compounds may be more fully developed.
Executive Summary: This report describes results toward developing a process to sequester CO2 using two CO2-utilizating enzymes ... . The process involves the use of bacteria to convert CO2 and glucose ... and generates succinic acid as a commodity chemical product.
We achieved a CO2 sequestration rate estimated to be as high as 800 mg/Lh. We were able to obtain consistent sequestration rates (which) indicate ... that the contents of a 1000 Liter vessel could consume 600 grams per hour CO2.
(Actually, that ain't all that great. You would need a danged-big reaction "vessel" to process a significant quantity of CO2. But, we think that's okay. Such a "vessel" could be placed anywhere, since sunlight isn't needed, and could be made out of anything. Further, the feed gas doesn't have to be pressurized and can contain what we take to be typical exhaust gas impurities. The implications, for us, suggest that the "vessel" could be simply a big pond next to a Coal-fired power plant into which the plant's exhaust gases are simply piped and, thus, scrubbed.)
We demonstrated that a defined medium could be used for the process, and that the process could be operated well in the pH range of 6.0 – 6.8, with a pH optimal of about 6.4.
The gas phase concentration of CO2 was observed to affect the sequestration rate significantly. That is, the higher the concentration of CO2 in the gas, the greater the rate of sequestration.
(Hot diggity! As immediately above, the more CO2, the better.)
The presence of trace amounts of impurities in the gas stream do not inhibit CO2 sequestration and succinate generation.
The gas impurities which either have no effect or promotesequestration slightly include NO2, SO2, CO and O2. The process is sufficiently robust to use on a wide variety of CO2 sources. This result warrants further study, as it suggests ... these gases provides a physiological advantage to the cell.
(Again, hot diggity! Typical exhaust gas impurities, from "a wide variety of CO2 sources" might actually provide "a physiological advantage to the" micro-organisms that convert CO2 into "succinate".)
Conclusions: We have been able to demonstrate CO2 sequestration at a rate as high as 800 mg/Lh, and
consistently over 600 mg/Lh, which exceeds the rate of CO2 sequestration previously attained (in
a photosynthetic system) by a factor of 40-50.
(Much better, in other words, that a photosynthetic, algae-based CO2 bio-reactor.)
CO2 sequestration rate is unaffected by agitation or other mechanical means to increase mass transfer.
(We don't, in other words, have to expend energy stirring the goop up and keeping it mixed.)
The presence of trace amounts of impurities in the gas stream generally promotes CO2 sequestration and succinate generation. The gas impurities which do not inhibit and may promote sequestration include NO2, SO2, CO and O2."
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First, we must note that these Georgia scientists, in at least one passage we haven't reproduced, caution that they don't think their process is quite yet ready for commercial implementation, even though it is, already, as a close read reveals, much better in Carbon Dioxide consumption and "sequestration" rates than the similar in concept, but sunlight-demanding, algae-based systems being more loudly and more broadly touted, for the production of bio-Diesel from algae.
And, they don't emphasize what might be a key point in their technology:
To form Succinate from Carbon Dioxide, Glucose is required as a co-reactant.
As learned in: Corn syrup - Wikipedia, the free encyclopedia; Glucose can be rather easily made from "any source of starch", including a wide variety of botanical - photosynthetic and CO2-recycling - sources.
And, as in:
Cellulose Degradation; "By: Nam Sun Wang; University of Maryland; Abstract: Currently, there are two major ways of converting cellulose to glucose";
we can also, on a commercial industrial basis, rather easily manufacture the Glucose needed to recycle Carbon Dioxide in, as above, the University of Georgia's robust and pollutant-tolerant process for the production of Succinate from CO2, from a wide variety of otherwise waste photosynthesized, and thus recycled, CO2, in the form of such things as saw dust and cast-away news rags.
In brief, non-technical sum:
We can directly recycle unpurified exhaust gas Carbon Dioxide, along with Carbon Dioxide that has already been botanically-recycled into Glucose, via a low-energy process that doesn't require the input of sunlight, and thereby manufacture a raw material for the chemical manufacturing industry useful in the production of "polymers" and "any number of" other "Value-Added Chemicals".