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CUSTOM DESIGNED ALGAE SYSTEMS SMALL- MEDIUM-LARGE-&-TURNKEY SYSTEMS    CO2 CAPTURE PROCESS HTC Purenergy (HTC)    1. The exhaust gas from the power plant is the source of CO2.The exhaust gas is cooled before it reaches the capture process itself in order to optimise the process. The flue-gas cooler is the largest consumer of cooling water in the process, typically using 50% of the cooling water .    2. The flue-gas will meet some physical resistance within the capture plant on its way to the atmosphere, and this will result in a certain pressure drop in the exhaust gas. In order to ensure that the power plant’s gas turbine does not suffer a loss of power because of the capture facility, a blower is located in the flue-gas duct, either before the cooling unit or between it and the actual capture plant.    3. From the blower, the gases are brought to the bottom of an absorption tower, which is filled with a packing material that offers a large surface that the absorption solvent follows on its way down through the tower. The solvent is an amine or a mixture of amines dissolved in water, which absorb the CO2 in the flue-gas as it flows upwards through the tower. The CO2 removal efficiency for flue-gases from gas-turbine exhaust will typically be 85%.    4. After the CO2 has been captured by the amine, it has to be released by heating the solvent. The desorption of CO2 takes place in the desorption tower, also known as a stripper. This is done by allowing the amine containing the CO2 to flow down the packing material that fills the tower, while steam and CO2 flow upwards. The steam has two functions:a) it transfers the necessary heat to the amine, and b) it draws the released CO2 out of the tower. The mixture of steam and CO2 that exits the top of the stripper is cooled down, and most of the steam is condensed while the CO2 remains in a gaseous phase.    5. The water is pumped back to the stripper while the CO2 is directed to the dehydration and compression stages and on to transportation.    6. The amine flows from the bottom of the stripper to the reboiler, where the steam used in the desorption process is generated. The heat for the reboiler is steam generated by heat from an external source. This reboiler is the largest consumer of heat in the CO2 separation process.    7. A flow of virtually CO2-free amine solution leaves the boiler and is led back to the absorber, where it once again absorbs CO2.    8. In the absorption tower, the reaction between CO2 and amine produces heat, with the result that a certain amount of amine and water will evaporate during the absorption process and be carried upwards through the tower along with the flue-gases. The gas is saturated with steam and amines . As well as losing a portion of the amines, the water losses will also be large. In order to minimise water losses and emissions of amines, a water-wash process is integrated at the top of the absorption tower.    9. Cold water with a low concentration of amines washes the flue-gases, dissolving the amines while the water balance is maintained by the steam being condensed by the cold water.   10. When the solvent comes into contact with the flue-gases, the amines will also react with other components in the flue-gas, such as O2 and NOx. How much of these are absorbed will vary from one amine to another, and will also depend on the design of the absorption tower. These reactions form heat-stable salts that will not be released from the amine solution by the stripping process. Since the amine mixture is circulated between the absorber and the desorber, the amount of heat-stable salts in the solvent will gradually rise. After a certain period of time, the concentration of these salts will be so high that the CO absorption rate will be reduced. This is handled by the use of a reclaiming unit.   11. A side stream of the circulated solvent is heated so that the water and amines evaporate and are led back to the process. When the water and amines have been boiled off, what remains at the bottom of the reclaimer is a viscous liquid that must be disposed of. The waste will contain some amines and water, but will consist mostly of heat-stable salts.   Example of CO2 capture plant 3-D rendering Example of Packing Material  CO2 COMPRESSION    1. After the CO2 has been separated from the flue-gas in the capture plant, it must be dried and compressed. This is done in a multistage process of compression, cooling and water separation.    2. Pressure, temperature and water content all need to be adapted to the method of transportation (pipeline or vessel) and pressure requirement at the storage site. A typical compression and dehydration process for pipeline transportation is illustrated schematically in Figure below    3. CO2 from the capture plant arrives at the dehydration and compression stage at about room temperature and at a little above atmospheric pressure. Apart from the CO2, the gas contains some steam and small fractions of impurities (nitrogen, oxygen, and traces of amines and other substances).   Flow diagram for CO2 compression and dehydration     4. When CO2 is being transported by pipeline, compression requirements are determined by the supply pressure at the delivery site and the pressure drop through the transportation pipeline. The pressure in the pipeline should always be high enough to ensure that the CO2 is in a supercritical state, i.e. above 50 – 70 bars, depending on the temperature. Where a simple storage solution is involved, the offshore supply pressure is 70 – 100 bars while the pressure requirement for EOR may be higher. In order to meet pressure requirements of this order, the pressure of the CO2 may be anything from 150 bars to 300 bars or higher as it leaves the capture plant, depending on the type of transportation and the storage pressure involved.     5. The combination of water and CO2 in a pipeline creates corrosive conditions, requiring the water content to be kept low and monitored continuously in order to avoid corrosion and hydrate formation. HTC Purenergy (HTC) is an energy technology company headquartered in Regina, Saskatchewan, Canada.  HTC was incorporated in 1996 and is listed on the Toronto Stock Exchange (Venture Exchange) under the symbol “HTC”. HTC’s business is the development, aggregation and commercialization of proprietary technologies, relating to carbon dioxide (CO2) capture, storage and hydrogen (H2) production utilizing CO2.  These technologies have been acquired, licensed, developed internally and developed in partnership with the University of Regina and The International Test Centre for CO2 Capture “ITC”, a leading centre of research for CO2 capture and storage. The establishment of a specialized commercial entity focusing on “carbon clear” technologies was driven by:     * Rapidly expanding international efforts to mitigate the adverse effects of greenhouse gas emissions on climate change, through:           o CO2 capture and sequestration (e.g. permanent underground storage);           o Rising conventional energy (oil & gas) prices, which make CO2 a valuable commodity as an agent for enhanced hydrocarbon recovery (e.g. Enhanced Oil Recovery);           o The need to provide the market solutions derived from the aggregation of market leading, fully validated technologies that could be commercially sourced from a single point of contact. That contact being an organization that could engage in commercial service and technology licensing agreements with commercial accountabilities and sustainability.