Optimized Acetone Separations Design
Team Leader: Kavita Nyalakonda
Design Engineers: Janet Huang, Hector Perez
November 8, 1999
Miller & Associates contracted Kavinetor, Inc. to develop and optimize a separations process simulation for a new acetone production plant. The reactor system for this acetone plant was modeled by Group C. Williams. Using their findings, Kavinetor was charged with the task of using the effluent from their reactor design and isolating acetone at a 99.9% purity. When achieving this purity, this model had to be technically sound and cost-effective.
Kavinetor utilized rigorous techniques, which involved a balance between design and economic considerations. Through the analysis of different column configurations and the resulting economic costs, an optimal design was found. This model met design specifications and economic feasibility. The optimized design was found to have a capital cost of $972,500, as compared to the preliminary design cost of $1,078,000. The utility cost of the optimized design was calculated to be $2,450,000, as compared to the preliminary design cost of $4,021,000. This resulted in an overall savings of 33% over a 20-year plant life.
Based on these results, Kavinetor recommends that this design should be implemented or undergo further analysis. Kavinetor has confidence in the design and economic analysis of this optimized simulation.
Table of Contents
Effectiveness of Required Separations
The Base Case
The Optimized Design
Waste Water Separation Column
Acetone Purifying Column
Economic Analysis of the Optimized Design
Kavinetor, Inc was contracted by Miller & Associates to perform project work on their acetone production plant, in conjunction with Group C. Williams. Group C. Williams had developed an optimized design for the reactor system of the acetone plant which produces acetone from the dehydrogenation of isopropyl alcohol. The purpose of Kavinetor’s project was to design a separations system to purify the product of this acetone production plant. The goal was to develop a cost-effective model that will provide an acetone product of 99.9 mol% purity and maintain the azeotropic recycle stream. The original model used by Miller & Associates was based on the model discussed in Turton. This report describes the methods that Kavinetor, Inc. used to optimize this preliminary process design and provides the corresponding results.
The Turton model produces acetone through the dehydrogenation of isopropyl alcohol (IPA). The process begins with an azeotropic mixture of IPA and water. This is mixed with a recycle stream of unreacted IPA and water, which is fed into the reactor system. The reactor effluent becomes the feed to the separation system, the area of the plant under consideration. The purification system consists of four separations units. The reactor effluent enters the system through a two-stage cooling system of two heat exchangers in series. The base case begins at the entrance of the effluent into the second heat exchanger. After cooling to an appropriate temperature, the stream is sent to a flash drum, where the vapor is separated from the liquid. The overhead, consisting mainly of hydrogen, is sent to a scrubber. The purpose of the scrubber is to remove hydrogen from the process stream. It uses process water from another part of the unit to scrub acetone and IPA from the hydrogen. The hydrogen exits the scrubber through the overhead. The bottoms of the scrubber combine with the bottoms from the flash drum and enter the first distillation column. The first column separates the acetone from IPA and water. The overhead contains the 99.9% pure product. The bottoms of...
References: 1. Arlt, W., Gmehling, J.and Onken, U. Vapor-Liquid Equilibrium DataCollection:Aqueous-Organic Systems (Supplement 1), Vol 1 Part 1a. Dechema, Frankfurt, 1981.
2. Arlt, W., Gmehling, J.and Onken, U. Vapor-Liquid Equilibrium Data Collection Organic Hydroxy Compounds, Alcohols and Phenols, Vol 1 Part 2b. Dechema, Frankfurt, 1978.
3. Bird, R.B., Stewart, W.E., and Lightfoot, E.N. Transport Phenomena. John Wiley and Sons, New York, 1960.
4. Gmehling, J.and Onken, U. Vapor-Liquid Equilibrium Data Collection: Aqueous- Organic Systems, Vol 1 Part 1. Dechema, Frankfurt, 1977.
5. Huang, Y.F, Personal correspondence on November 1, 1999 by phone.
6. Hyprotech Corporation. Hysys Reference Guide 1. 1997.
7. Kister, Henry Z. Distillation Design. McGraw Hill, New York, 1992.
9. Seader, J.D. et. Al. Process Design Principles: Synthesis, Analysis, and Evaluation. John Wiley & Sons, New York, 1999.
10. Turton, Bailie, Whiting, and Shaeiwitz. Analysis, Synthesis, and Design of Chemical Processes. Prentice Hall PTR, 1998, p. 728–735.
11. Williams,C. et. al. Acetone Production Via Isopropanol Dehydrogenation: Reactor Design. 1999.
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