Tamar Hallerman
GHG Monitor
04/27/12
The Electric Power Research Institute is moving forward on compiling a ‘state of the science’ assessment of the methods researchers are using globally to gauge the potential environmental impacts of amine solvents emissions once they degrade in the atmosphere. In recent months, EPRI has assembled an international working group of more than a dozen members who have experience with the solvent and are compiling a report of all of the methods being used worldwide to measure the possible public health and environmental impacts of the solvent once emitted, EPRI researchers said, as well as identify where the knowledge gaps are in terms of those methods.
The group held a workshop on the issue last summer to gauge the state of research on the topic that drew roughly 70 people. That meeting, EPRI staffers said, highlighted the lack of global coordination on the issue, which prompted the organization to start a research effort to try and measure the work being done so far. “We are at the very early stages of trying to bring the community involved in this topic together to do some state of the science assessments of what methods exist for understanding the emissions of these chemicals, what knowledge gaps exist and what the next priorities of research directions should be to either answer these gaps or improve the performance of those methods such that in a number of years down the road we will be in the direction where we will be directing our research resources in a way where we can get to methods that can be standardized,” Stephanie Shaw, a senior project manager at EPRI, told GHG this week. Leaders of the effort will be presenting on their efforts next week at the Eleventh Annual Conference on Carbon Capture, Utilization and Sequestration in Pittsburgh.
Scale-Up Issues Raise Flags
Originally developed for oil and gas applications as an agent for removing CO2 and other compounds from gas streams, amine solvents are now one of the world’s most mature carbon separation technologies. Their use has particularly boomed in recent years due to the deployment of aqueous monoethanolamine (MEA) for scrubbers as retrofit technology for older coal-fired power plants. However, questions surrounding the technology emerged in recent years as it was scaled up for commercial use. Preliminary research conducted by the Norwegian Institute of Public Health over the last several years suggested that during the CO2 separation process, while most of the amine solvent is recycled back into the plant to be used again after initial carbon separation, a small percentage of the compound is released into the atmosphere. While the Norwegian researchers estimated that amines alone pose little threat to public health and the environment, they raised concerns about the potential for carcinogenic compounds being formed when the amines degrade and react with other materials in the environment. Those compounds could form nitramines, amides and nitrosamines, the later of which is considered highly toxic to humans even at low concentrations, the Norwegian Institute of Public Health said.
The issue emerged on the political forefront last spring when the Norwegian government said it would delay making a final investment decision on its Mongstad CCS demonstration project until 2016, citing concerns over the lack of information on the health and environmental impacts of amine technology. The announcement caused some in the field, particularly private industry groups that manufacture amine solvents, to research the issue on their own. However, much of that testing has so far remained private due to proprietary concerns surrounding the individual amines being tested, GHG previously reported, and companies are not required to publically disclose what they use in their solvents, their research methods or the potential impacts of their solvents on public health and the environment. Because of that information void, little substantial research on the technology exists in the public realm, the reality that prompted EPRI to hold the initial meeting, researchers said.
Identifying Knowledge Gaps
Shaw said that the goal of the working group is to compile a list of measuring methods being utilized around the world and identifying knowledge gaps that exist in the research by the end of the year, which will eventually be made publically available. “Our next step would then be to understand what kind of testing could be done to address those knowledge gasp and how that could occur,” she said, adding that a possibility down the line could be to design a sample testing program for analyzing amines and their degradation products that could eventually be tested using non-proprietary amines like MEA at neutral testing facilities but that there are no plans in place as of now. “We are not yet developing a standardized methodology for the measurement of amines or amine degradation products in post-combustion capture systems,” she said. Shaw added that the current goal is to gauge where the community is in terms of which knowledge gaps exist. “We are trying to get the experts that are trying to do this work at the pilot scale right now or in the lab together at this early starting point to see what we can say as a community in terms of what we know and what we don’t know,” she said.