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Today Friday Feb. 7. Turning our abundant coal ( or just about anything else with carbon) into scarcer petroleum and gas, by chemical engineering. The Fischer- Tropsch process All power point images are only for the exclusive use of Phys3070/Envs3070 Spring term 2014. Fungible Fuels.
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TodayFriday Feb. 7 Turning our abundant coal ( or just about anything else with carbon) into scarcer petroleum and gas, by chemical engineering. The Fischer-Tropsch process All power point images are only for the exclusive use of Phys3070/Envs3070 Spring term 2014
Fungible Fuels Coal to gas Coal to liquids Gas to liquids Rely on heat energy inputs, catalysts, and chemical engineers.
Coal to gas or liquids Water gas C + H2O+heatH2 + CO Fischer-Tropsch (2n+1)H2 + nCO + heat CnH2n+2 + nH2O Net formula to make C10H22 HW#3
The ‘gaslight era’ • Cities had ‘gas works’ • Made gas from coal • ‘water gas’ or ‘coal gas’
Coal gas or water gas C + H2O+heatH2 + CO With the heat from burning coal (carbon) in the same place. Which both burn in air 2 H2 +O22 H2O + heat 2CO + O22 CO2 + heat
Syngas Continue the process, with the H2 and CO under different conditions of pressure and temperature 3H2 + COCH4 + H2O which works in the presence of ‘catalysts’ in a ‘shift reactor’ Catalysts are reaction accelerators, not consumed. ‘catalytic converter’ in cars (text page 306).
syngas H2 and CO Coal gas
In situ gasification Drill a hole into the coal formation, perhaps using fracking. Light the coal on fire Pipe down air and steam Chemical reactionH2 and CO Bring up the gasses by another pipe. 80% of the heat energy of the coal is in the gas! Coal is both fuel and feedstock Most of the mess stays underground
In situ Gas to liquids Fischer -Tropsch (2n+1)H2 + COCnH2n+2 + nH20
Coal to gas or liquids Water gas C + H2O+heatH2 + CO Fischer-Tropsch (2n+1)H2 + nCO + heat CnH2n+2 + nH2O Net formula to make C8H18 Which is gasoline, octane
The drawback The F-T process creates CO2 From burning the coal to run the process From burning the resulting gasoline in cars. Net CO2 production is twice that from burning gasoline from petroleum The South African SASOL F-T plant is the world’s largest single producer of CO2.
Monday—be prepared to tell us all about what this means. Compare to present coal production
NEW TERM One mol = the mass of a molecule in atomic units, in grams
Next week Monday: Overview of fossil fuels,. Review Ch.2 and class presentations. The big picture. CAPA #2 is due, closes at 0900 Wednesday: heat engines, Chapter 3 Friday: efficiency of heat engines. Monday Feb. 17 Exam 1, Chapters 1-3
Monday --grand review of fossil fuels 1. which is the largest source of US energy overall now? in 100 years? 2. which is the largest contribution to transportation energy? 3.Which is the largest contribution to electrical energy? 4. Which ones are changing most/least rapidly? why? 5. What about energy imports/exports? 6. What is the idea behind Hubbert curves? 7. Why is energy intensity decreasing? is this good?
more • Can you balance atoms in simple chemical reactions? Atoms are forever! • Can you balance masses in those reactions? Making CO2? • What does 44/12 mean to you? • Can you smoothly translate among energy units? • How does power differ from energy? • Your turn…..
Tell me What would you most like me to review about fossil fuels?