Energy Citations Database (ECD) - - Document #795267
In a recent dispatch, now accessible via:
USDOE Finances Ohio CO2 Recycling | Research & Development; we made report of:
"US Patent Application 20020072109 - Enhanced Practical Photosynthetic CO2 Mitigation; 2002; Inventors: David Bayless, et. al., Ohio; Government Interests: The U.S. Government has a paid up license in this invention. Abstract: An on-site biological sequestration system (that) directly decreases the concentration of carbon-containing compounds in the emissions of fossil generation units."
All of the inventors named in that application are, or at least were, on the faculty of Ohio University; and, we attributed that US Patent Application to work that had been done by Ohio University under:
"USDOE Contract Number: FC26-00NT40932; Enhanced Practical Photosynthetic CO2 Mitigation; 2006; Authors: Gregory Kremer, David Bayless, et. al.; Ohio University".
However, the dates of the patent application and the USDOE report obviously don't match up very well; nor, do any of the published contract numbers. And, we have since discovered that both that application and the later DOE research contract, might, in fact, have arisen from earlier Carbon Dioxide recycling work performed by the same team of OU scientists for the Department of Energy.
Comment follows excerpts from the initial and following links to:
View Document or Access Individual Pages
Title: Carbon Dioxide Mitigation Through Controlled Photosynthesis
Authors: Dr. David Bayless, et. al.
Date: October, 2000; OSTI ID: 795267; USDOE Contract Number: FG26-99FT40592
Abstract: This research was undertaken to meet the need for a robust portfolio of carbon management options to ensure continued use of coal in electrical power generation.
In response to this need, the Ohio Coal Research Center at Ohio University developed a novel technique to control the emissions of CO2 from fossil-fired power plants by growing organisms capable of converting CO2 to complex sugars through the process of photosynthesis.
Once harvested, the organisms could be used in the production of fertilizer, as a biomass fuel, or fermented to produce alcohols. In this work, a mesophilic organism, Nostoc 86-3, was examined with respect to the use of thermophilic algae to recycle CO2 from scrubbed stack gases. The organisms were grown on stationary surfaces to facilitate algal stability and promote light distribution. The testing done throughout the year examined properties of CO2 concentration, temperature, light intensity, and light duration on process viability and the growth of the Nostoc. The results indicate that the Nostoc species is suitable only in a temperature range below 125 F, which may be practical given flue gas cooling.
Further, results indicate that high lighting levels are not suitable for this organism, as bleaching occurs and growth rates are inhibited. Similarly, the organisms do not respond well to extended lighting durations, requiring a significant (greater than eight hour) dark cycle on a consistent basis. Other results indicate a relative insensitivity to CO2 levels between 7-12% and CO levels as high as 800 ppm. Other significant results alluded to previously, relate to the development of the overall process. Two processes developed during the year offer tremendous potential to enhance process viability.
First, integration of solar collection and distribution technology from Oak Ridge laboratories could provide a significant space savings and enhanced use of solar energy.
(We have been investigating the Oak Ridge lab's development of light distribution technologies for application in photosynthesis-based CO2 recycling systems, and will report on their work in coming days. But, again, the strain of "organism" utilized herein does require "dark cycles" and can use lower light levels.)
Second, the use of (known) technology could both enhance organism growth rates and make the process one that could be applied at any fossil-fired power generation unit.
Background: Biological carbon sequestration offers many advantages. Photosynthesis is the natural way to
recycle carbon. Biomass developed from photosynthesis has numerous beneficial uses, the most
attractive being a replacement fuel.
Despite the large body of research in this area, virtually no work has been done to create a practical photosynthetic system for greenhouse gas control, one that could be used with both new and existing fossil units. For example, raceway cultivator use ignores land availability limitations at existing fossil generation plants. Few existing generation plants could find 100+ acres of suitable land for siting a microbial pond, much less build and maintain one throughout a Midwestern winter.
(A) practical biological sequestration would require improved lighting and photon delivery, a harvesting process to remove non-viable organisms and promote maximum carbon utilization, consideration of deleterious effects of the flue gas temperature and composition, and a plan for utilizing the biomass. The proposal presented in this document attempts to address these relevant problems in the design and analysis of a practical system for using photosynthesis in carbon sequestration.
(The) product of natural sequestration, biomass, has numerous practical uses ranging from fertilizer to fuel.
(And) engineered photosynthesis systems could be made attractive to industry because they require no high-risk scientific breakthroughs. Photosynthesis is well understood, but there are no integrated practical processes for using it at fossil units for carbon sequestration.
The concept behind affordable engineered photosynthesis systems is simple. Even though CO2 is a fairly stable molecule, it is the basis for the formation of complex sugars by green plants through photosynthesis.
The relatively high content of CO2 in flue gas (approximately 14% compared to the 350 ppm in ambient air) has been shown to significantly increase growth rates of certain species of cyanobacteria.
Therefore, this application is ideal for contained system, engineered to use specially selected (but currently existing) strains of cyanobacteria to maximize CO2 conversion to cyanobacterial biomass and thus not emitting the greenhouse gas to the atmosphere.
In this case, the cyanobacteria biomass represents a natural sink for carbon sequestration.
(A "sink" for CO2, we are compelled to emphasize, which, unlike a Geologic Sequestration scheme that would "sink" a ton of money in addition to the CO2, actually offers a payback: "replacement fuel".)
Enhanced natural sinks ("the cyanobacteria biomass") are the most economically competitive and environmentally safe carbon sequestration options because they do not require pure CO2, and they do not incur the costs (and dangers) of separation, capture, and compression of CO2 gas.
(Unfortunately, some of the direct CO2 recycling technologies we've previously documented, as in:
Exxon Recycles By-Product CO2 to Methanol | Research & Development; concerning: "United States Patent 6,495,609 - Carbon Dioxide Recovery in ... Ethylene Oxide Production; 2002; ExxonMobil Chemical Patents, Inc., Texas; Abstract: Disclosed is a method for recovering carbon dioxide from an ethylene oxide production process and using the recovered carbon dioxide as a carbon source for methanol synthesis";
just might require the additional expenses of some such "separation, capture, and compression of" CO2. However, that expense might be justified since such processes generate greater amounts of more specific products, such as "methanol", with direct and specific high-value applications.)
Among the options for enhanced natural sinks, the use of existing organisms in an optimal way in an engineered photosynthesis system is low risk, low cost, and benign to the environment. Additionally, this engineered photosynthesis system has the advantage of being at the source of the emissions.
(And, thus, the people living near "the source of the emissions" could benefit from the employment and the overall economic stimulus resulting from such "use of existing organisms" to recycle CO2.)
For low-concentration CO2 streams, such as the 14% mean CO2 concentration in waste flue gases from coal-fired power plants, the joint consideration of conversion of collected solar energy (using the Oak Ridge process) and natural carbon capture has the potential for significantly lowering carbon management costs.
An engineered photosynthesis system can use ... waste CO2 to generate a store of reduced carbon in the form of biomass that could be used as a fuel (and) fertilizer.
The process presented in this proposal would be suitable for application at existing and future fossil units. It also has several advantages compared to other natural sequestration techniques. For this project, optimization is based on design of a mechanical system to best utilize existing organisms rather than on optimizing the desirable features of an organism by genetic manipulation.
(Thus avoiding having the anti-genetic engineering troglodytes meld with the various suspect anti-Coal groups to form some Frankenstein-type monster of specious, obstructionist protest.)
The process also requires relatively small amounts of space (1/25th of a raceway cultivator design) and most of the required energy is provided by passively collected sunlight.
(Thus accommodating both the confined spaces of the Coal Country river valleys where many Coal-fired power plants are situated; and, through the Oak Ridge lab's system for "passively" collecting and distributing "sunlight", all of the Coal Country cloudy days, as well.)
From a solar energy utilization standpoint, this proposal offers a unique and cost-effective alternative using a new hybrid system that leverages two decades of advancements and cost improvements in the solar, optical coating, and large-core optical fiber industries. This method far surpasses previous attempts at distributing sunlight to enhance cyanobacteria growth (and) could be used in virtually any power plant."
----------------------
Seriously, it must be emphasized that the Carbon Dioxide recycling concept detailed herein "could be used in virtually any power plant", where, likely, the waste heat from the power plant could sustain the process "throughout a Midwestern winter".
And, thus, any money earned by sale of the "fuel (and) fertilizer" produced by such an "engineered photosynthesis system" would return, through wages and taxes, to the vicinity of "any fossil" fuel-based "power plant" where such a facility might be installed.
Where, we must ask, if the threat of Cap & Trade taxation forces us to turn to the alternative of Geologic Sequestration of CO2 in old oil wells, with the resultant enhancement of oil recovery from those old wells, would the money from the sale of that secondarily-recovered oil, and the jobs that money would support, go?
Where would Cap & Trade taxes go?
Not, we would guess, to the vicinity of "any" US Coal Country "power plant"