Future Challenges and Opportunities Jeff Siirola Purdue University Carnegie Mellon University 29 September 2011.

Future Challenges and Opportunities

Jeff SiirolaPurdue UniversityCarnegie Mellon University 29 September 2011

Carbon Management

Design and Control for Sustainability

Shale Gas

Reduce Carbon Dioxide Production Offset Carbon Dioxide Production Carbon Dioxide Capture Carbon Dioxide Storage

Reduce energy usage◦ Produce less product (change product portfolio)◦ Decrease energy use per unit of production (process

improvement)◦ Recover and reuse energy (process intensification and

heat integration)

Switch to a more energy-intense fossil source for fuel and feedstock◦ Switch from oil to gas◦ Switch from coal to gas

Use non-carbonaceous energy sources◦ Solar-wind◦ Solar-photovoltaic◦ Solar-thermal◦ Geothermal◦ Nuclear◦ Wave◦ Tidal◦ Solar-hydroelectric

Change reaction chemistry to produce less carbon dioxide

Burn fossil fuel but harvest and bury/sink an equivalent amount of biomass/biochar

Cultivate (crop), recover (residues), or recycle (waste) biomass for fuel and feedstock◦ Burn biomass directly for heat and power◦ Biologically or chemically convert biomass to alternative

fuel (e.g., bioethanol, biobutanol, or biodiesel)◦ Pyrolyze/gasify biomass and convert to alternative fuel◦Convert biomass into chemical feedstock

Convert recovered carbonaceous wastes into fuel or feedstock

Sell carbon dioxide or a carbon dioxide derivative for any permanent use

Chemically reduce carbon dioxide to lower oxidation state◦Reform carbon dioxide with methane to syngas◦Reduce carbon dioxide collected from processes,

flues, or the atmosphere with hydrogen produced from nonfossil energy (nuclear, solar, geothermal) into fuel and feedstock

Capture from low pressure point sources – fluegas◦ Alcoholamines◦ Chilled ammonia◦ Caustic or lime◦ Carbonate◦ Zeolite adsorption◦ Active transport membranes◦ Anti-sublimation

Capture from high pressure point sources – gasifiers◦ Rectisol◦ Selexol◦ Metal oxides

Collect from fluegas without nitrogen◦ Oxygen-fired furnaces, kilns, or turbines (oxyfuel)

Capture from mobile sources◦ Lithium hydroxide◦ Polymer amines◦ Molecular sieves

Collect from atmosphere by scrubbing◦ Caustic◦ Anion exchange resins◦ Optimized reactive sorbent

Collect from atmosphere by growing biomass◦ Cultivated crops, plantation forest, algae ponds◦ Natural aquatic and terrestrial vegetation and forests

Geologic (as pressurized gas, supercritical liquid, or carbonic acid; +4 oxidation state)◦ Porous capped rock (with or without oil recovery)◦ Coal beds (with or without methane displacement)◦ Deep saline aquifer

Oceanic (+4 oxidation state)◦ Ocean disposal (as carbonic acid)◦ Deep ocean disposal with hydrate formation◦ Ocean disposal with limestone neutralization (as

bicarbonate solution)

Land disposal as carbonate salt (+4 oxidation state)◦ Reaction with silicate

Energy conservation◦Easier to justify with expansions rather than retrofits◦Capital costs rise with energy costs

Fuel switching◦Limited gas pipeline capacity◦Coal boiler derating◦Relocation to inexpensive stranded gas results in

expensive product transportation costs

Biomass◦ Growth depends on latitude and rainfall (and soil)◦ Land competition with agricultural use◦ Low energy density – high transportation costs

Other solar◦ Low source intensity – high capital costs◦ Variable availability

Nuclear◦ No experience with nuclear process heat◦ Shutdowns for refueling◦ Siting concerns

Post-combustion (partial pressure, strength, and purity of sorbent◦Chemsorption (hydroxides, amines, carbonates)◦Physical sorption (alcohols)◦Phase change (anti-sublimation)◦Membrane

Pre-combustion (gasification capital) Oxy-combustion (air separation expense)

Energy required to recover CO2 and regenerate sorbent

Enhanced oil recovery Coalbed methane displacement Depleted reservoirs Saline aquifers Ocean disposal (without or with neutralization) Pipeline transportation network Leak monitoring and mitigation

Compression and injection energy

Minimized compression costs => higher recovery pressures

High recovery pressures => high stripping temperatures High stripping temperatures => stable sorbents Stable sorbents => inorganics => ammonia Hydroxide/carbonate energetics => strip ammonium

bicarbonate only to ammonium carbonate Volatile ammonia => low temperature absorber Low temperatures => expensive refrigeration Less volatile sorbent => potassium carbonate Poor kinetics => absorption “catalyst” (piperazine)

Avoid ocean acidification => dispose as bicarbonate Alkalis expensive => use calcium (or magnesium) Alkaline earth bicarbonates do not exist as solids =>

prepare and dispose of as bicarbonate solutions Alkaline earth bicarbonates have limited solubility => use

ocean water Ocean water transport cost => limit to power plants near

Atlantic, Pacific, and Gulf coasts (60% of all plants) Avoid carbon dioxide stripping energy => absorb with

limestone slurry and do not recover sorbent Slow absorption kinetics => a challenge to be addressed

No good solutions Fuel switching (NG and CNG) Atmospheric carbon capture◦Also to reverse atmospheric carbon concentration◦Very low source concentration (400x lower than fluegas)◦Huge air handling requirements◦Requires strong or very well stripped sorbents◦Total process energy same order of magnitude as heat of

combustion of coal◦High cost compared with growing and burying biomass

Reprocessing and waste storage◦ Addressed by Gen IV technologies (transmutation)

Loss of coolant◦ Addressed by scale-down (natural convective cooling)

Reliable process heat◦ Addressed by multiple and redundant units◦ Use of the grid to dispose of excess power as electricity

Chemical fuels◦ Nuclear water splitting (hydrogen) to produce fuels from coal,

biomass, or even carbon dioxide

Historically, the chemical processing industries were designed to run on steam and compressed air

What would happen if all we had was electricity?◦Resistance heat?◦Heat pumps, vapor recompression, etc?◦Membranes, centrifuges, and other mechanically-driven

separations?

Electrically dominated chemical processing

In the short term, in the absence of a carbon tax, cap-and-trade scheme, or other incentives, concentrate only on energy consumption (and carbon dioxide generation) minimization

Prepare infrastructure to enable fuel switching from coal to natural gas

Postpone further carbon capture and storage technology evaluation pending improved clarity of regulations impacting all competitors

Considering the renewed emphasis on energy minimization,

We tend to DESIGN for energy minimization

But during operations, we rarely CONTROL for energy minimization

We control instead for production rate, product purity, other fitness-for-use criteria, and disturbance rejection at the EXPENSE of energy (the manipulated variable)

The same is also true for many other sustainability dimensions◦Environmental impact minimization◦Raw material and other resource use efficiency◦Customer and stakeholder value◦Health and safety◦Climate change

We consider sustainability attributes when selecting and optimizing among alternatives during design, but rarely control for these same objectives during operations

Intensified application of manufacturing intelligence using advanced sensors, modeling, and very large scale simulation

Encompasses the technology, interoperability, operational practice, and shared business infrastructure on which manufacturing intelligence can be generated and applied to multiple sustainability objectives including economic, energy, environment, health, safety and other performance metrics

View sustainability as objectives to be optimized rather than simply as regulatory constraints

Many more sensors and monitors Real-time error detection and data reconciliation

and very large scale dynamic simulation Engineering modifications to increase

operational degrees of freedom Optimized control of energy consumption,

environmental impact, and other sustainability objectives in addition to production rate, quality, and fitness-for-use product objectives

Essentially the integration of Real Time Optimization and Model Predictive Control

Enabled by numerous inexpensive sensors, massive computing infrastructure, and clever engineering

Monitoring of every individual utility consumption point

Various aspects of the Smart Grid

Active control of individual tray hydraulics at incipient flood for maximum efficiency

Cogeneration for commercial sale

Natural gas is the fuel that powers most (but not quite all) US chemical and refining processes

Natural gas methane is the feedstock for hydrogen production (for hydrocracking, hydrodesulfurization, and ammonia) and for syngas (for methanol, and its derivatives e.g. MTBE, formaldehyde, and acetic acid)

Natural gas condensate (ethane and propane) is an advantaged raw material via ethylene and propylene to much of the organic chemicals industry (compared to crude-oil-derived naphtha)

Crude Oil• Global supply and demand• Established oceanic transportation network• Productive capacity and risk premium• Impact of speculation

Natural Gas• Local supply and demand• Transportation limitations• Limited US conventional supply• New shale gas production technology

Coal• Excess productive capacity• Inexpensive extraction technologies• Environmental impact issues

Chemicals from methane◦Methanol production moves offshore to sources of

stranded gas◦MTBE abandoned as gasoline oxygenate◦Ammonia moves to Canada◦Hydrogen becomes expensive (and low-sulfur diesel at

the pump becomes more expensive than regular gasoline)

Chemicals from condensate and naphtha◦Condensate price rises with natural gas (for awhile)◦Ethylene price spikes◦Propylene price finally rises higher than ethylene

Shut down older cracker capacity Abandon some ethylene derivatives (polyethylene)

and seek C1 routes to others (ethylene glycol, acetaldehyde) as previously done for acetic acid/anhydride)

Abandon polypropylene Seek C1 routes to propylene (MTP) for existing oxo

derivatives and other intermediates currently made from propylene (acrylics, methacrylics, acetone, etc)

Developed process for the large-scale gasification of petcoke, lignite, or coal as source of syngas for C1 chemistries and refinery hydrogen

Flight to off-shore production (to sources of stranded methane and condensate - Persian Gulf)

Bio-based feedstocks (ethylene from sugar-based bioethanol dehydration - Brazil)

Feedstocks from coal gasification and liquefaction (China)

Calls for increased US LNG infrastructure Development of directional and horizontal drilling

and hydraulic fracturing technologies (Shale Gas)

Unconventional natural gas (as is coalbed methane, tight sandstone gas, and methane hydrates)

Found in relatively thin shale formations of very low permeability

Economic production enabled by two technological innovations:◦Directional drilling◦Hydraulic fracturing

Technology and field development encouraged by high natural gas prices

Shale gas now reclassified as conventional gas US conventional gas reserves doubled Price of natural gas halved

Accelerate electric power fuel switching from coal to natural gas

Killed proposed Eastman gasification project Restored US production of methanol and ammonia Condensate crackers restarted Restored advantaged US feedstock position for many

organic chemicals

Natural gas replacement for coal as the primary early carbon management technique (source reduction)

Increased deployment of highly efficient Natural Gas Combined Cycle plants for electricity production and chemical plant cogeneration

Increased US production and export of chemicals decreasing the trade deficit

For many intermediates, interesting competition between C1 (methane) and C2 (ethane) feedstocks resulting from advances in catalysis, energy efficiency, and process design optimization

Depends on how long shale gas remains plentiful and whether it is wet or dry

If plentiful and wet, then the existing US ethane-based chemical industry infrastructure will remain world-competitive

If plentiful but dry, new C1 chemistries will emerge, but based on methane steam reforming syngas

If oil shale is developed using directional drilling and hydraulic fracturing gas shale technology, the role for naphtha cracking infrastructure may be extended

Electricity power plant fuel switching could dominate the rate of shale gas development

Amount of gas producible from shale formations might be less than predicted

Additional shale formations might be more expensive to produce than first experiences suggest

Some shale formations might be geologically inappropriate for development (e.g. shallow formations near groundwater supplies)

Production technologies (especially hydraulic fracturing) might have unintended environmental consequences leading to political or regulatory restrictions

If a great deal of infrastructure is put in place to displace coal by natural gas for electricity production and for institutional and industrial boilers and to otherwise expand the use of methane for chemical production,

But natural gas becomes less economically advantaged compared to coal…

Then coal gasification may once again return, But if so, most likely only to make Synthetic Natural

Gas (SNG)!◦ With the corresponding carbon dioxide captured and

sequestered

It is good to be back