Cryogenic Carbon Capture

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1 Cryogenic Carbon Capture

2 Sustainable Energy Solutions Sustainable Energy Solutions Sustainable Energy Solutions (SES) was founded in 2008 in response to a growing need for solutions to sustainability problems within the energy industry. SES is primarily focused on the development and commercialization of Cryogenic Carbon Capture, a patented carbon capture technology developed in Since its founding, SES has filed several additional patents on multiple technologies to help realize SES' mission: Create practical solutions to help solve energy problems on a regional and global scale. Cryogenic Carbon Capture The Cryogenic Carbon Capture (CCC) technology is a patent-pending process designed to separate a nearly pure stream of CO 2 from power plant gases. This technology adds a process to the plant after normal energy production where CO 2 is separated from the exhaust gases. Energy storage is also possible using the CCC process. This allows for increased use of renewable energy resources and helps to balance the power grid when incorporating intermittent energy sources (e.g., wind, solar) that produce power at non-peak demand times. The Cryogenic Carbon Capture technology offers the most cost effective and practical solution to carbon capture, compared to amine and oxy-fuel combustion, in today's market.

3 Cryogenic Carbon Capture Process The Cryogenic Carbon Capture (CCC) process is being developed in 2 variations: the Compressed Flue Gas (CFG) and External Cooling Loop (ECL) processes, where each variation includes flue gas conditioning (e.g. removes particulates & water, pre-cools), desublimating heat exchange, recuperative heat exchange, solid separation, and CO 2 pressurization steps. In the CFG process, the flue gas is modestly compressed and cooled to slightly above the frost point of CO 2. The gas is then expanded, further cooling the stream. In the ECL process, a refrigeration loop is used in lieu of the expansion step for the final required cooling. The final result is liquid CO 2 and a clean gaseous nitrogen stream. Compressed Flue Gas (CFG) Process Gaseous N 2 -rich Stream Pressurized Liquid CO 2 Stream Flue Gas Condensing Heat Exchanger Dry Gas Heat Exchanger Liquid Pump Make-up Refrigeration Separator Separator Moisture Compressor SO 2, NO 2, Hg, HCl Solid CO 2 Bypass Expansion Solid CO 2 Stream Pressurizer N 2 -rich Steam External Cooling Loop (ECL) Process Flue Gas Heat Exchanger And Dryer Water Heat Recovery Expansion SO 2, NO 2, Hg, HCl Solid Separation Refrigeration Loop Solid Compression Heat Recovery Pressurized, Liquid CO 2 Pump N 2 -rich Light Gas Compression Ambient Heat Exchange

4 Energy Storing Cryogenic Carbon Capture The Energy Storing Cryogenic Carbon Capture (ES-CCC) process is comprised of the Energy Storage process integrated into the External Cooling Loop (ECL) process. The ECL process includes flue gas conditioning (e.g. particulate & water removal, pre-cooling), desublimating heat exchange, recuperative heat exchange, solid separation, and CO 2 pressurization steps. A refrigeration loop is used for the final required cooling, but most of the cooling is recuperated in the system. The process produces liquid CO 2 and a clean gaseous nitrogen stream. The Energy Storage process integrates into the ECL process such that liquefied natural gas (LNG) is produced during energy storage. This LNG is used as a refrigerant in the red refrigeration loop (below) during energy recovery and the warm, low-pressure natural gas is combusted in the NG turbine at the bottom of the diagram. During normal (non-energy storage) operation, this loop uses another refrigerant. The Energy Storage process is described further on the next page. External Cooling Loop (ECL) Process with Energy Storage

5 Energy Storing Cryogenic Carbon Capture Under normal operation (right), the CCC process does not involve NG power generation or flow of NG into the system. The coal combustor generates flue gas that is treated by the CCC process and results in a nitrogen-rich effluent stream and a pressurized CO 2 stream. A compressor provides all of the energy demand of the CCC process, with energy represented by a lightning bolt into the compressor. During energy storage (left), the process differs only in that the compressor load increases (two lightning bolts) so that additional NG can be prepared as a liquid and stored in the LNG storage vessel. Nothing flows out of the LNG storage, and the NG turbine set does not operate. During energy recovery (right), the process eliminates the parasitic compressor demand and operates only from the stored LNG. The LNG first provides cooling for the CCC process and then, to avoid storage at lowpressure, room-temperature conditions, passes through a NG turbine generation set. The air and NG would not be in the same compressor, as suggested by this simple diagram. However, the compressed NG and air burn in a turbine. This energy storage process minimizes the parasitic load on the coal-fired plant due to carbon capture via CCC. The process also generates additional energy in the form of power from the NG turbine.

6 Temperature Basic Principles Cryogenic Carbon Capture is not a refrigeration loop. The inlet and outlet streams in the process are at approximately the same temperature. The minimal cooling required to drive the process, indicated by ΔT 1 (above), is significantly less than the cooling required for traditional refrigeration, indicated by ΔT 2 (above), where the outlet product is significantly colder than the inlet stream. This diagram shows that the sensible energy for a simple system is very low, but it does not address the other energy demands. Flue Gas Heat Exchanger And Dryer Water Expansion Heat Recovery SO2, NO2, Hg, HCl Solid Separation Refrigeration Loop Solid Compression Heat Recovery Pressurized, Liquid CO2 Pump N2-rich Light Gas Compression Ambient Heat Exchange ΔT 2 refrigerant flue gas ΔT 1 ΔT 1 is all that is needed to achieve the overall temperature decrease Distance

7 CO 2 Capture Efficiency CO 2 Capture Since 2010, Sustainable Energy Solutions has run various experiments demonstrating CO 2 capture from simulated flue gas. Capture efficiency is maintained by maintaining heat exchanger temperatures during each run, as predicted in the plot above. Modeled and demonstrated results show consistent CO 2 capture of 90% or more over multiple runs under many conditions. 100% Representative Cryogenic Carbon Capture Run 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Time (hr)

8 SO 2 Capture Efficiency Pollutant Removal An experiment was conducted at SES using simulated flue gas with 400 ppm SO 2. This experiment showed a 99.8% capture efficiency (right). The SO 2 concentration in the outlet stream is so low that it approaches the measurable limit of the gas analyzer. 110% 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Time (hr) The mercury and air toxics removal capabilities are shown in the bottom plot. At the temperature where 90% of the CO 2 in coal is captured (-118 C), all of the mercury in the coal and >99% of the mercury in the air is also captured.

9 Bench-scale Process A bench-scale process has been completed to demonstrate the CCC process, in its entirety, on a small scale. This process accommodates heat exchanger testing and further optimization of the process for design and construction of larger-scale demonstrations. Labview bench-scale control system. Primary coldbox containing (clockwise, from top left) the desublimating heat exchanger, liquid cooler, gas recuperator, contact liquid pump, and contact liquid reservoir.

10 Skid-scale Process Two larger, skid-scale CCC processes are also in the design stages, with construction to begin in The compressed flue gas (CFG) CCC skid-scale demonstration process is funded by ARPA-E and the U.S. Department of Energy (shown above). The external cooling loop (ECL) CCC skid-scale demonstration process is funded by the State of Wyoming and the U.S. Department of the Interior. These mobile skid-scale systems will demonstrate the CO 2 capture capability of the CCC process using a slip-stream from a coal-fired power plant. The skid-scale ECL process will be adaptable to include energy storage.

11 Total Plant Cost ($/kw) Parasitic Load *including contingencies /kw Energy and Cost Comparison 16 Levelized Cost of Electricity 30% Parasitic Load % 20% 15% 10% 5% * based on 550 MW NETL Case 11 0 Base Case CCC Amine 0% CCC Amine In 2007 (updated 2010), NETL published a report 1 on the impact of carbon capture on fossil energy plants. Using the same costing model as used in that report, the incremental cost increase caused by Cryogenic Carbon Capture is less than that required by amine carbon capture (above, left). The parasitic loads (above, right) for CCC and amine carbon capture are 15.6% and 27.6%, respectively. Additionally, the energy demand for Cryogenic Carbon Capture is also significantly lower than that required by amine carbon capture (below, left). As a true retrofit process, CCC implementation costs (below, right) are a small fraction of the capital cost required to build new power plants to incorporate carbon capture, even when including the construction of new plants with CCC to compensate for the lost capacity due to parasitic loads. GJ/tonne CO Energy to Capture CO 2 CCC Amine CCC Retrofit Total Plant Cost 1 Cost and Performance Baseline for Fossil Energy Plants. Volume 1: Bituminous Coal and Natural Gas to Electricity Revision 1 (2007) DOE/NETL-2007/1281 Revision 2 (2010) DOE/NETL-2010/1397 Base Case CCC Amine

12 CCC Integration The Cryogenic Carbon Capture process offers more than just removing CO 2 from flue gas. When combined with SES s patent-pending energy storage option, CCC facilitates the use of solar and wind energy by storing excess energy during low energy demand periods and using that stored energy during peak demand times. In addition to helping balance the grid, this energy storage also effectively reduces the parasitic energy required for CCC, lessening the impact on the cost of electricity due to carbon capture. Integration advantages include: 1. Energy efficient and cost effective CO 2 capture 2. Bolt-on technology with broad application 3. Multi-pollutant removal capabilities (captures SO 2, SO 3, NO 2, Hg, HCl and recovers some H 2 O) 4. Energy storage and grid management 5. Safety, compatibility and simplicity (uses unit operations common to power plants with no toxic materials or other unusual hazards) Clean Exhaust Gas Biomass Intermittent Wind Power Coal Fired Power Plant Electricity Cryogenic Carbon Capture N2, O2, Trace Gases FUEL MIXTURE Exhaust Gas CO2 & Pollutants Electricity Produced Energy Stored Coal Electrical Consumer Cryogenic Storage Tank Geologic CO2 Sequestration

13 For Further Information Sustainable Energy Solutions 1193 South 1480 West Orem, UT 84058