Recovery and Purification of HFC by Distillation

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Recovery and Purification of HFC by Distillation

• Ramin Afrasiabi
• Tony Calabria
• John OBrien
• Chemical Engineering 160
• November 28th, 2000

BIG-D Chemicals
2
Motive for Project

• Chlorine atoms from CFCs induce the decomposition
  of ozone (O3) in the stratosphere.
• Replacement of the ozone-destroying CFCs
  refrigerants with the environmentally-friendly
  HFC-125 refrigerant.

3
Project Background
Design Project Focus
HCl
Reactor Effluent, Feed to Distillation Train
Series of Distillation Columns
Feed to Upstream Reactor
Reactor
HFC-125
CFC-115
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Project Goals

• Design Conventional and Extractive Distillation
  Processes to Recover HFC-125, CFC-115, and HCl.
• Compare Economics of Two Competing Processes
• Recommend Cost-Efficient Scheme Based on Economic
  Results

BIG-D Chemicals
5
Project Timeline
-Preliminary Database Creation
08/00
-Determined Mass and Energy Balance Requirements
using Aspen Tech Simulator
09/00
-Equipment Sizing
10/00
-Calculated Fixed and Variable Costs
11/00
-Profitability Analysis
11/00
-Commence Plant Construction
01/01
-Project Completion/Commissioning
12/02
-Salvage Plant
12/15
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Conventional Distillation for HFC Recovery
HCl Product
Raw Feed
HFC Product
BIG-D Chemicals
Feed to T-202
CFC Product
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Extractive Distillation For HFC Recovery
HFC Product
HCl Product
Extractant Feed
Raw Feed
CFC Product
Extractant Recycle
BIG-D Chemicals
8
Equipment Sizing

• Unit Operations
• Distillation Towers
• Compressors
• Pumps
• Condensers
• Reboilers
• Pressure Vessels
• Sized Using Aspen Simulation Results

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Sizing Heat Exchangers

• Modeled using LMTD
• Input (from Aspen)
• Heat Duty
• Hot, Cold Temperatures
• Appropriate Materials
• Output
• Overall HTC (U)
• tubes / pass
• HT Areas
• Dimensions

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Equipment Cost Analysis
CBM f (equipment size, operating pressure,
material of construction)
Extractive
Conventional

• CBM includes
• Equipment Purchase Cost
• Materials
• Labor

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Variable Cost Analysis (Scheme I)
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Profitability Analysis

• Purpose To Determine
• Extractive Conventional
• Fixed Cost Variable Cost lt
  Fixed Cost Variable Cost
• Calculated
• - Earnings (S COS D taxes)
• - Annual Cash Flow
• - Net Present Value _at_ 15
• Cash Flow Discounted To Present Worth
• Sum of Discounted Cash Flows NPV

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Bottom Line

• NPV Calculated
• Over 15 Years

2015 NPV for Scheme II is 2.5 MM greater than
Scheme I
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Recommendation / Future Plans

• Scheme II Promises Greatest Economic Potential
• Submit Plant Design for Contractor Bid (Dec.
  2000)
• Commence Plant Construction (Jan. 2001)
• Commission Plant Addition (Dec. 2002)

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Acknowledgments

• Professor Wallman
• Professor Lynn

BIG-D CHEMICALS