Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 26
Novel Approaches to Carbon Management: Separation, Capture, Sequestration, and Conversion to Useful Products - Workshop Report 6 Crosscutting Issues REQUEST FOR PROPOSAL STRUCTURE AND PROJECT MANAGEMENT In the course of the workshop, each subgroup addressed various issues of overall program management. This chapter of the report summarizes those discussions. Although the purpose of the expanded DOE/FE program is to elicit novel concepts for carbon management and to reach more widely into the scientific community, the initial number of awards will be small and the initial funding for each project will also be small. The labor required for a full proposal may deter some of the very people DOE/FE desires to attract because of the low probability of success and the small stakes. DOE/FE could utilize a preproposal process, which invites a short, 3- to 5-page submission, followed by a limited invitation for full proposals. This process would have two benefits: (1) DOE/FE would receive more proposals with less early work required from researchers; and (2) DOE/FE may identify productive collaborations among preproposers that would not otherwise happen. Within DOE, both the Office of Science and Office of Environmental Management have used a preproposal process successfully. The committee expects that DOE/FE will receive a range of proposals varying from specific technologies to systems concepts to fairly narrow exploratory research questions. To put them on a somewhat level playing field, it was noted that the request for proposals (RFPs) could require each full proposal to include a simple energy and materials balance analysis. Such an analysis would demonstrate that the proposer understands the larger technological context into which the project fits, even if it addresses initially a narrow but critical research question. This analysis needs to demonstrate that the scale of carbon sequestration achieved is commensurate with the problem, that the thermodynamics are real, and that there is some consideration of cost. The committee recognizes that some of the people DOE/FE wants to attract might not have the capacity to undertake this analysis on their own. The RFP could suggest collaborations with engineering groups, or DOE/FE could relax the rigor of this requirement in the first round. It might also consider establishing an internal DOE/FE group that could help proposers with this analysis. The committee is also concerned about the postaward management of the program. The encouragement of communication among the awardees and other performers in the carbon sequestration program will be critical. DOE/FE could consider the establishment of annual sequestration review meetings that include presentations from the novel concept awardees. This would foster broader awareness of the new work but also facilitate collaborations that will advance both the novel concepts and the nearer-term projects. The committee also notes that as the early awards mature, additional support may be necessary before investigators transition to other parts of the carbon sequestration program. In particular, exploratory research projects may transition to larger, multidisciplinary efforts requiring larger amounts of funding.
OCR for page 27
Novel Approaches to Carbon Management: Separation, Capture, Sequestration, and Conversion to Useful Products - Workshop Report CROSSCUTTING ANALYTICAL AND ENGINEERING ISSUES A few subgroups identified crosscutting technical issues that were not carbon management ideas per se but rather engineering and analytical issues associated with long-term carbon storage. Three such issues are described below. Monitoring and Containment Technologies Following Subsurface CO2 Sequestration Once CO2 is sequestered in the subsurface by some means, it will be necessary to monitor the sequestered CO2 to determine whether leakage is occurring. By necessity, detection technologies must be low in both capital and operating costs, highly sensitive, and capable of monitoring large areas of Earth’s surface. The latter capability is essential, because the sequestered CO2 may be spread out over large areas of the subsurface. Equally vital are technologies that will be able to heal leaks in the subsurface. Sequestration of CO2 may take different forms, ranging from storage in saline aquifers and deep subsurface coal beds to deep-ocean disposal methodologies; therefore, technologies to seal leaks must be diverse and effective in a range of subsurface environments. CO2 is likely to be stored in a variety of forms, ranging from pressurized CO2 in subsurface environments to immobile mineralized forms. In some storage scenarios, the liquefied CO2 will seek cracks and fractures in the geologic formation, abandoned wells in depleted oil fields, wormholes in the deep-ocean sediment storage areas, or tears in such proposed storage methods as deep-sea bladders filled with CO2. Although catastrophic CO2 release is unlikely in most storage schemes, slow leakage is likely. These slow leaks not only must be identified but also must be effectively repaired to ensure secure storage of the carbon for long periods of time. Technology Opportunities Monitoring technology must be capable of detecting CO2 leaks through the existing atmosphere, on the terrestrial surface, on the ocean surface, and in the deep ocean. Technology concepts for monitoring could include such things as “tagging” the stored CO2 with an odorant such as hydrogen sulfide (H2S) or a mercaptan that could be detected by gas analyzers, radioactive isotopes that could be traced, or spectrally detected compounds such as sulfur hexafluoride (SF6). Hyperspectral satellite imagery or change-conditions technology in a global monitoring context may offer technical opportunities for monitoring. For deep-ocean disposal, such as in a pressurized bladder that resides on the deep-ocean floor, an array of pH meters to monitor changes in ocean water pH may be sufficient. Highly effective sealing technologies that can be employed remotely in the deep subsurface environment or the deep ocean must be identified and engineered. Opportunities may exist in technological extensions to conventional grouting methods, new polymer sealants may be developed, or biofilms and other biological methods may be developed for selectively sealing leaks. Promising technological developments need to be tested for effectiveness as engineered barriers to CO2 mobilization.
OCR for page 28
Novel Approaches to Carbon Management: Separation, Capture, Sequestration, and Conversion to Useful Products - Workshop Report Subsurface Technologies: Risk Assessment In the workshop discussions, it was suggested that DOE/FE request that each group or person submitting a proposal include a very introductory risk-benefit analysis of their research idea. This would then serve as the very beginning of a risk assessment for the concept. The preliminary risk assessment would provide context for considering the benefits of a carbon sequestration method. Risk assessment, also known as total system performance assessment, could be utilized to estimate quantitatively the success of a subsurface carbon sequestration method. Risk assessments are based on conceptual models, which incorporate features, events, and processes that individually or in concert are judged capable of disrupting the ability of a sequestration system to contain CO2 (or other chemical form of sequestered carbon). Quantitative probabilities are assigned to the occurrence of various events (e.g., seismic activity) and processes (groundwater flow), and estimates are made of the associated consequence—the amount of CO2 released. Risk assessment can be used as a tool to develop a CO2 release standard—that is, a level of CO2 release that is judged safe and acceptable, taking into account distances from human populations and fate and transport of CO2, among other factors. Risk assessment of subsurface CO2 containment systems can leverage the existing capability of risk assessment of underground disposal (e.g., of nuclear waste), so cost for the risk assessment is not likely to be a barrier. Implementation could be accomplished swiftly, and information could be made available to decision makers about the suite of subsurface carbon sequestration methods. Research Opportunities Research opportunities in the area of risk assessment are as follows: Development of conceptual models and inventories of features, events, and processes; Application of risk assessment methods to candidate sequestration ideas and candidate sequestration sites; and Development of an environmental CO2 release standard. Engineering Systems Analysis for Optimum CO2 Reduction or Sequestration There is a major need for conceptual engineering analyses of novel process schemes as an adjunct to laboratory exploration of process elements. Early conceptual analysis for material and energy balance will provide for early screening of new technology concepts to ensure that fundamental physical laws have not been violated. These analyses would be specific to concepts developed for the niche technologies envisioned, as exploratory investigations advance. Systems analysis, including preliminary cost analysis, would provide an opportunity to identify critical areas of accomplishment required for technical and/or economic success. While excessive use of such analysis can cripple innovation, its proper use can help identify and focus on the issues and needs that will ultimately affect success or failure.
OCR for page 29
Novel Approaches to Carbon Management: Separation, Capture, Sequestration, and Conversion to Useful Products - Workshop Report Research Opportunities Research opportunities in the area of engineering systems analysis for optimum CO2 reduction or sequestration would include developing basic information and methodologies to evaluate and compare the following: Risk of human tragedy; Potential for a major, abrupt reversal; Magnitude of interaction with the environment; Degree of the environmental unknowns; Energy required per unit (per unit=per unit of CO2 emission reduced); CO2 disposed/CO2 processed; Materials to be disposed of per unit; Materials inputs required (e.g., nutrients) per unit; Capital cost per unit; Potential for continuous low-level leakage; Physical footprint per unit; Potential for remediation if/when a problem arises; Operating cost per unit; Potential for technology improvement; Time required to commercialize; and Total size of the opportunity.
Representative terms from entire chapter: