Commodity Products CHEMICAL PRODUCT ENGINEERING ASEP MUHAMAD SAMSUDIN.
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Transcript of Commodity Products CHEMICAL PRODUCT ENGINEERING ASEP MUHAMAD SAMSUDIN.
Chemical Products
Category of Product
Class of Product Example Key Attribute
Specialty chemicals
Surfactant Ammonium lauryl sulfate
Molecular structure
Formulated products
Cosmetic Exfoliating gel Microstructure
Bio-based concepts Drug Alendronate sodium
Biological activity
Devices Biomedical device Blood oxygenator Materials and assembly
Virtual chemical products
Software to simulate chemical processes
Aspen Plus Computational performance
Technology-based consumer goods
Health care consumer goods
Disposable diaper Materials and assembly
R. Costa and G. D. Moggridge
R. Costa, G. D. Moggridge, P. M. Saraiva. Chemical Product Engineering: An Emerging Paradigm Within Chemical Engineering. AIChE Journal, 52 (2006) :1979
Chemical Products
Commodities Chemical Devices Molecular Products
Microstructures Products
Examples Ethylene, ammonia Artificial kidneys Penicillin Sunscreen
Scale Continuum Meters Nanometers Micrometers
Key Cost Convenience Discovery Function
Basis Reaction Engineering, Unit operations
Reaction Engineering, Unit operations
Chemistry Recipe
Risk Feedstock Intellectual Property Discovery Science
Cussler and Moggridge
Cussler EL, Moggridge GD. Chemical product design. 2nd edition. Cambridge: Cambridge University Press; 2011.
Based on the characteristic size scale which is critical to their performance
Commodity Products
The core of the chemical industry. Simple molecules produced in large quantities (over 10,000 tons/year) at the lowest possible cost.
Fewer than 50 of the more than 30,000,000 compounds which are known.
The molecular weights are typically less than 100 daltons.
The king of these product is liquid fuel: gasoline, petrol, diesel
The key chemical and physical properties of the commodity products : key scale, chemical reactivities and volatilities.
We can use the same design template of needs, ideas, selection and manufacture to improve manufacturing itself.
Example 1Ammonia from nitrogen and hydrogen
Needs A product purity above 95%.
An amount over 10,000 tons/year.
Price already defined by the market.
A production cost perhaps 20% less than the price
Example 1Ammonia from nitrogen and hydrogen
Ideas Derive from the four step outline suggested by Douglas
(1988)
Batch Vs. Continuous Process
Inputs and Outputs
Reactors and Recycles
Separation and Heat Integration
Example Ammonia from nitrogen and hydrogen
First : decide weather we use a batch of continuous one Experience suggests that for commodities a continuous process
will almost always be cheaper.
Second : draw a flow diagram. A chart illustrating the flow of different chemical stream in the reactor.
Example Ammonia from nitrogen and hydrogen
Third: recognize that this process will not involve complete reaction For the conventional Haber process, only get perhaps 20%
conversion.
The process must have a reactor followed by some sort of separator.
Example Ammonia from nitrogen and hydrogen
Fourth: Douglas suggests more detailed identification of separation required. The gases from the reactor are chilled to 10oC to condense liquid
ammonia, and the non-condensables are recycled.
Part of this recycle is purged to get rid of the argon.
Significant amounts of nitrogen and hydrogen dissolve in the liquid ammonia.
One the pressure is released (to about 20 bar), the dissolved gases can be removed by simple distillation for recycle and recompression.
Example Ammonia from nitrogen and hydrogen
IDEAS.
1. Seek better catalyst.
2. Get rid the argon and so not waste the hydrogen and nitrogen necessarily discarded with the purge.
3. Invent a better, more selective separation
Example Ammonia from nitrogen and hydrogen
SELECTION The catalyst, the firs area for study, has received the
greatest effort. The original Iron oxides used by Haber as catalyst.
The activity of catalyst can be enhanced by trace quantities of many metals, especially ruthenium.
Removing argon, which is the second area of interest, would certainty possible by liquefying air and distilling off the nitrogen. While the separation of argon from oxygen is difficult because the difference in boiling points is so small.
We can infer that this distillation is too expensive, costing much more than purging the argon and wasting some nitrogen and hydrogen.
Example Ammonia from nitrogen and hydrogen
SELECTION We may decide to focus on the third area, a better
separation of ammonia from the other gases.
We may select three good idea : A membrane 100 times more permeable to ammonia than to nitrogen and hydrogen at room temperature
A similar membrane selective and stable at reactors temperature
An adsorbent selective for ammonia at reactor conditions.