By Sai Gollakota (National Energy Technology Laboratory, U.S. Department of Energy) and Scott McDonald (Archer Daniels Midland Company)
The large-scale industrial CCUS project, also referred to as the Illinois ICCS project, is being demonstrated at the ADM’s agricultural processing and biofuels complex in Decatur, Illinois. It is cost shared with funds from the American Recovery and Reinvestment Act of 2009, is being demonstrated under the DOE’s Industrial Carbon Capture and Storage (ICCS) program.
The Office of Fossil Energy’s National Energy Technology Laboratory (NETL) manages the project, which receives $141.4 million in Recovery Act funding and another $66.5 million in private sector cost-sharing. The project team members are ADM, DOE, Schlumberger Carbon Services, University of Illinois-Illinois State Geological Survey (ISGS), and Richland Community College (RCC).
The project will demonstrate an integrated system for capturing CO2 from ADM’s ethanol plant and geologically storing it in the Mount Simon Sandstone, a saline reservoir that covers portions of the Midwest including central and southern Illinois. The CO2 is produced as a co-product during the processing of corn to fuel-grade ethanol.
The project scope includes the design, construction, and integrated operation of CO2 capture, compression, dehydration, and injection facilities. Additionally the project will develop and implement a monitoring, verification, and accounting program for the stored CO2.
The technology demonstrated and the lessons learned from this project will aid the development of the regional CCUS industry related to CO2 capture and transport infrastructure for enhanced oil recovery in the depleted oilfields in the Illinois Basin.
NETL and ADM Partnership
NETL is part of the DOE’s national laboratory system and it is owned and operated by the DOE. NETL implements a broad range of energy and environmental research and development programs in the areas of coal, natural gas, and oil technologies, and CCUS. NETL is developing a portfolio of safe, cost-effective, commercial-scale CCUS technologies for deployment by the industry.
NETL also conducts analyses of energy systems and international energy issues.
Archer Daniels Midland Company (ADM) global headquarters is located in Decatur, Illinois. Its more than 265 processing plants and 30000 employees convert corn, oilseeds, wheat, and cocoa into products for food, animal feed, chemicals and energy uses. The net sales of ADM in fiscal year 2012 were $89 billion.
ADM, as part of its comprehensive strategy for energy sustainability and environmental responsibility, is implementing the Illinois ICCS project to reduce carbon footprint of industrial processes, e.g., by permanently storing the CO2 generated during ethanol production in deep underground rock formations, rather than releasing it into the atmosphere. Successful demonstration of this cutting-edge technology will have significant implications for commercialization of CCUS
ADM is already operating the first DOE-sponsored CCUS project in Decatur. This project, led by ISGS, is referred to as the Illinois Basin-Decatur Project (IBDP). This is a large-volume, saline reservoir sequestration test that will inject one million tonnes of CO2 over a period of three years. IBDP has completed construction of a 1000 tonnes per day CO2 compression and dehydration facility, drilled and completed the associated injection and deep monitoring wells, and established an extensive CO2 monitoring program.
The injection well is located adjacent to ADM’s Decatur ethanol plant. The IBDP has compiled extensive geologic data for this CO2 storage site. The IBDP completed one year of successful operation and injected over 320000 tonnes of CO2 into the Mt. Simon Sandstone. The injection will continue for another two years, followed by three years of post-injection monitoring.
ADM’s experience from the IBDP project enabled expanding the CCUS capability to that of a commercial-scale operation (907000 tonnes per year) in the second project, i.e., Illinois ICCS project. To reach commercial scale, upon completion of the IBDP injection operations in the fall of 2014, ADM will integrate the IBDP compression and dehydration facilities with the new facilities constructed under the Illinois ICCS project.
At its October 2012 annual meeting in Perth, Australia, the Carbon Sequestration Leadership Forum, an international carbon storage organization, officially recognized the Illinois ICCS project and the IBDP for advancing CCUS technologies.
Illinois ICCS Project Objectives
The project will demonstrate an integrated system for collecting CO2 from an ethanol plant and geologically sequestering it in a saline reservoir:
• Design, construct, and operate a new CO2 collection, compression, and dehydration facility capable of delivering up to 2000 tonnes of CO2 per day to the injection site.
• Integrate the new facility with an existing 1000 tonnes of CO2 per day compression and dehydration facility to achieve a total CO2 capacity of up to 3000 tonnes of CO2 per day.
• Design, construct, and operate a storage site capable of accepting up to 3000 tonnes of CO2 per day. Implement deep subsurface and near surface monitoring of the stored CO2.
CO2 Capture, Compression, and Dehydration
The following is a brief description of the new CO2 capture, compression, and dehydration facility being constructed under the Illinois ICCS project. The CO2 produced during the ethanol fermentation process is a high purity CO2 stream (greater than 99% purity on a moisture free basis), with water content less than 3% by weight.
First the CO2 coming off the fermentation tanks is directed to a water wash column to remove any entrained ethanol or other water soluble components. Next the water saturated CO2 exits the top of the scrubber at near atmospheric pressure and 37.8oC and is transported via a 0.91 m diameter pipeline to a collection facility where is passes through a water separator before being compressed to 0.24 MPa using a 2238 kW 4-stage gas blower.
After compression, the CO2 is cooled from 93.3°C to 35°C using a 3370 kW plate and frame heat exchanger. Next, a separator removes any free water produced during cooling and the CO2 stream is transported through a 0.61 m diameter, 457 m long pipeline to a compression and dehydration facility.
At this facility, the gas is divided into four parallel streams that each feed a 4-stage, 2424 kW reciprocating compressor resulting in a total compression capacity in excess of 2000 tonnes per day.
Each compressor has six cylinders; two cylinders for the 1st stage, two cylinders for the 2nd stage, one cylinder for the 3rd stage, and one cylinder for the 4th stage of compression. After each stage of compression, the interstage gas is cooled to 35°C using condensing water which is then removed by an interstage separator.
During the 1st stage, CO2 is compressed to 0.52 MPa with a discharge temperature of 145°C. During the 2nd stage CO2 is compressed to 1.71 MPa with a discharge temperature of 156°C. In the 3rd stage, CO2 is compressed to 4.1 MPa and 123°C. At this point, after cooling and free water separation, 95% of the water entering the process has been removed through compression and cooling.
After the 3rd stage of compression, the four CO2 streams are recombined and sent to the triethylene glycol (glycol) dehydration unit. The combined CO2 stream enters the bottom of the glycol contactor where it is contacted with the lean glycol (water free) introduced at the top of the unit. The glycol removes water from the CO2 by physical absorption and the rich glycol (water saturated) exits the bottom of the column.
The dry CO2 stream leaves the top of the contactor and passes through an outlet cooler, which cools the gas to 35°C before returning to the compression section. The glycol regenerator consists of a column, an overhead condenser, and a natural gas fired reboiler. In this column, the glycol is thermally regenerated by hot vapor stripping the water from the liquid phase.
After the CO2 leaves the dehydration section, it splits into four streams each stream returning to the 4th stage of the reciprocating compressor where it is compressed to 9.8 MPa and 133°C. After this stage, CO2 is cooled to 35°C.
Finally, the dehydrated CO2, which has less than 0.005% moisture by weight (>99.9% CO2 purity), will be further compressed up to 15.8 MPa using a 298 kW centrifugal booster pump and transported 1610 m through an 0.2 m diameter pipeline to the injection wellhead. The injection operations will be conducted adjacent to the ethanol plant on a site owned by ADM. The injection wellhead conditions will comply with the permit requirements.
This project will store CO2 in the Mt. Simon Sandstone, an extensive saline reservoir in the Illinois Basin with the capacity to store billions of tons of CO2. Saline reservoirs are layers of porous rock that are saturated with brine (a concentrated salt solution). Mt. Simon Sandstone is a clean sedimentary rock dominated by silicate minerals and lacking significant amounts of clay minerals (which typically clog pores and reduce porosity), resulting in highly favorable porosity and permeability features for CO2 storage.
The Illinois ICCS project will initially inject CO2 into the Mt. Simon Sandstone at a rate of 1500 tonnes per day. The IBDP will also inject CO2 at a rate of 1000 tonnes per day during this period. The Illinois ICCS project’s injection rate can be increased up to 3000 tonnes per day once the IBDP completes injection operations in the fall of 2014. Each project will have a separate injection well and the distance between the two wells will be approximately 1128 m.
At the injection location, the top of the Mt. Simon Sandstone is at a depth of 1677 m below the surface and has a thickness of 457 m. The CO2 will be injected into the lower Mt. Simon at a depth of about 2134 m. Carbon dioxide injection will occur at depths far below the Underground Source of Drinking Water level thus ensuring the safety of these water sources.
The Mt. Simon Sandstone is overlain by the 152 m thick Eau Claire formation, of which the bottom 61 m is primarily shale. The low-porosity Eau Claire Shale acts as the primary cap rock seal preventing upward migration of CO2 from the Mt. Simon Sandstone. Two other shale formations, the Maquoketa Shale and the New Albany Shale, are present at shallower depths and act as secondary and tertiary seals, respectively. The base of the Mt. Simon Sandstone is underlain by Precambrian igneous bedrock (granite basement).
Monitoring the Stored CO2
The Illinois ICCS project will implement a robust plan to monitor CO2 migration and to protect groundwater sources. The monitoring efforts will employ methods to provide an accurate accounting of the stored CO2 and a high level of confidence that it will remain permanently stored deep underground. The monitoring plan includes near surface and deep subsurface activities.
The near-surface monitoring includes soil CO2 flux measurements to monitor changes in CO2 concentrations and shallow groundwater sampling for geochemical analysis. The deep-subsurface monitoring includes geophysical (seismic) surveys and passive seismic surveys in the above cap rock seal locations and geophysical surveys, geochemical sampling, and pressure and temperature monitoring in the injection zone.
A baseline 3D surface seismic data acquisition and analysis, performed by ISGS and Schlumberger Carbon Services, did not indicate any seismically resolvable faults in the reservoir or in the cap rock seal at the proposed Illinois ICCS injection site. A lack of geologic faults offers greater certainty that the injected CO2 will be stratigraphically trapped in the Mt. Simon Sandstone.
National Sequestration Education Center
Public education and outreach on CCUS is an integral part of this ICCS project. The project team is conducting an integrated communication, outreach, training, and education initiative, which is engaging stakeholders in understanding CCUS.
To promote knowledge sharing in CCUS, a 1390 sq m center containing classrooms, training and laboratory facilities, called the National Sequestration Education Center, was established at RCC in September 2012. RCC is implementing a new associate degree program, first in the U.S., with an emphasis on CCUS (i.e., Associate of Applied Science in Engineering Technology with Sequestration Specialty and Associate of Science with Sequestration Concentration, a university transfer degree).
Project Schedule and Status
The Illinois ICCS project construction was initiated in May 2011. Detailed design and mechanical installation of the compression and dehydration equipment have been completed, and piping, electrical, and instrumentation installation is in progress. A 2207 m deep monitoring well and a 1084 m deep geophysical well were drilled. U.S. Environmental Protection Agency Region 5 is reviewing ADM’s application for injection well permit approval, i.e., Underground Injection Control permit to construct and to operate Class VI injection well for the purpose of geologic sequestration of CO2.
The project is scheduled to commission and startup in 2013. Initially the project plans to operate at an injection rate of 580000 tonnes per year, and achieve the target injection rate of 907000 tonnes per year in the fall of 2014 when IBDP completes its operations. Project completion date for the DOE funding period is September 30, 2015.
Broader Benefits of the Project
Because all of the captured CO2 is produced from biologic fermentation, a significant feature of the Illinois ICCS project is its “negative carbon footprint,” meaning that the storage results in a net reduction of atmospheric CO2. Successful implementation of this project could:
• Facilitate exploration of long-term CO2 utilization options, such as enhanced oil recovery in the Illinois Basin and carbonate-based chemicals production;
• Develop a market for the CCUS technology in the U.S. for some of the approximately 200 fuel grade ethanol plants that have access to geologic storage.
• Develop a market for utilization of U.S. geologic saline storage capacity of CO2 that is estimated to range from 1700 to 20000 billion tonnes.
The Illinois ICCS project, being implemented under the DOE Award No. DE-FE-0001547, is administered by the Office of Fossil Energy and managed by NETL. The contributions of the following team leads are acknowledged in project implementation: Dr. Robert Finley (ISGS), Eric Berlin (Schlumberger Carbon Services), and Dr. Douglas Brauer (RCC).
The activities reported in this paper were performed as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.