PDF Publication Title:
Text from PDF Page: 035
3.4.1 Reference CDU process The MeOH synthesis route (direct hydrogenation of CO2) proposed by Van-Dal and Bouallou [91] is selected as the reference process due to the availability of data to calibrate and validate our model. Their proposed flowsheet has been simulated and optimised using a pinch point analysis (i.e. the integrated CDU process in Section 3.4.2) in order to decrease the needs of external sources of energy. Methanol production is 1 320 t/day at a purity of 99.9 wt %. Therefore, 41 000 std. m3/h of CO2 at ambient pressure and temperature and 123 000 std. m3/h of H2 at 25 bar and ambient temperature are fed. This leads to a stoichiometric mixture, according to Eq. (9). The reactor is operated with controlled feed conditions at 76 bar and 210 °C. The commercial catalyst Cu/ZnO/Al2O3 is used in this process due to available information on its operational performance (consumption, selectivity). The reaction rate is lower with only CO2 than when used with mixtures of CO/CO2 [20]. The flowsheet of the reference process is depicted in Figure 2. The thermodynamic model used in CHEMCAD is the non-random two-liquid model (NRTL) (see Appendix 2 for further detail). The CO2 feed stream 1 is compressed through a four-stage compressor with intermediate cooling. It is assumed that the CO2 enters the system at 1 bar. The compressors 1, 3, 5 and 7 are modelled as adiabatic compressors with an isotropic efficiency of 0.75. The pressure increase of each compressor is approximately Pout/Pin ≈ 3, leading to a final pressure of 78 bar in stream 9. Intermediate cooling in heat exchangers 2, 4, and 6 is performed with water at 28 °C, which is heated up until it reaches a 10 degrees difference with the temperature of the inlet gas stream. Hot water leaving these heat exchangers (and heat exchanger 14), at temperatures between 80 and 155 °C, is then used in an organic Rankine cycle (ORC) to generate electricity (about 2.2 MW), which can be used in the synthesis process or sold into the market. The gas stream is cooled down to about 38 °C after each cooler. The H2 feed stream 8 is compressed with compressor 8 from 30 up to 78 bar. Streams 9 and 10 are mixed with the compressed recycle stream 20 and fed to heat exchanger 10, where they are heated up with a fraction of the reactor outlet stream 14, to reach the reactor inlet temperature of 210 °C. Reactor 11 is modelled as an adiabatic ideal plug flow reactor (PFR), according to the kinetics for Eq. (9) and Eq. (10) as in [91]. The complex rate equations are directly implemented in CHEMCAD. The amount of catalyst utilised is 44.5 t of Cu/ZnO/Al2O3 [91]. The fixed bed volume that is obtained is 42 m3. Gaseous stream 13 leaves the reactor at 290 °C, with a MeOH content of 4.7 vol. %. The conversion of CO2 into MeOH is around 21 % in the reactor. About 0.4 % of the incoming CO2 is converted to CO due to Eq. (10). Stream 13 is divided into two streams, following heat integration purposes. Stream 14, which is used to heat the reactor feed in heat exchanger 10 (split fraction 0.6); and stream 32, which is used in reboiler 22 that belongs to the distillation column (unit 21), and to preheat the feed to the column in heat exchanger 20. After this heat integration, the streams are mixed again and cooled down to 35 °C in heat exchanger 14, allowing for the condensation of almost all MeOH and water. Gas and liquid phases are then separated in flash vessel 15. The released heat is transferred to a stream of water, which will be used in the ORC. Gas stream 18, which is mainly composed by H2 and carbon oxides, is compressed and recycled back to the reactor. About 1 % (split fraction 0.01) of the recycle stream is purged (stream 35) to avoid the accumulation of inert gases. Note that all purge streams are collected and brought to a furnace. The condensed liquid 21 is throttled to the pressure of 1.2 bar. The released gas is separated in another flash vessel (unit 19) and purged and collected (stream 36). Condensate 23 is an almost gas-free mixture of MeOH and water with a MeOH concentration around 63 wt %. This mixture is preheated and partially evaporated in heat exchanger 20, using heat from the reactor off-gas. Then, the two-phase stream is fed to distillation column 21. This unit is modelled with 57 equilibrium stages, fed at stage 44 (counted from the top) (according to the values in [91]). A reflux ration of 1.2 and a reboiler duty of 21.2 MW, are required to reach the design specifications of MeOH purity 33PDF Image | evaluation of CO2 utilisation for fuel production
PDF Search Title:
evaluation of CO2 utilisation for fuel productionOriginal File Name Searched:
ld1a27629enn.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)