Recovery and Purification of HFC by Distillation Ramin

Recovery and Purification of HFC by Distillation Ramin Afrasiabi Tony Calabria John O’Brien Chemical Engineering 160 November 28 th, 2000

Motive for Project l Chlorine atoms from CFCs induce the decomposition of ozone (O 3) in the stratosphere. l Replacement of the ozone-destroying CFCs refrigerants with the environmentally-friendly HFC-125 refrigerant.

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

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

Project Timeline 08/00 -Preliminary Database Creation 09/00 -Determined Mass and Energy Balance Requirements using Aspen Tech Simulator 10/00 -Equipment Sizing 11/00 -Calculated Fixed and Variable Costs -Profitability Analysis 11/00 01/01 12/02 12/15 -Commence Plant Construction -Project Completion/Commissioning -Salvage Plant

Conventional Distillation for HFC Recovery HCl Product Raw Feed HFC Product Feed to T-202 CFC Product

Extractive Distillation For HFC Recovery Extractant Feed HCl Product HFC Product Raw Feed CFC Product Extractant Recycle

Equipment Sizing l Unit Operations – Distillation Towers – Compressors – Pumps – Condensers – Reboilers – Pressure Vessels l Sized Using Aspen Simulation Results

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

Equipment Cost Analysis • CBM = f (equipment size, operating pressure, material of construction) Extractive Unit T-101 T-102 T-103 Condenser-101 Condenser-102 Condenser-103 Liq. Accum. -101 Liq. Accum. -102 Liq. Accum. -103 Reboiler-101 Reboiler-102 Reboiler-103 Pump-101 Pump (make-up str. ) Compressor-101 Heat Exchanger 101 Bare Module Cost ($) 282, 178 423, 869 988, 920 13, 828 12, 835 13, 170 22, 314 24, 989 27, 897 26, 928 30, 463 27, 234 50, 164 Negligible Conventional Unit Bare Module Cost ($) T-201 243, 926 T-202 1, 100, 561 Condenser-201 23, 996 Condenser-202 23, 212 Liq. Accum. -201 23, 621 Liq. Accum. -202 30, 257 Reboiler-201 34, 177 Reboiler-202 32, 365 Pump-201 59, 824 • CBM includes ØEquipment Purchase Cost ØMaterials ØLabor

Variable Cost Analysis (Scheme I)

Profitability Analysis • Purpose To Determine: Extractive Fixed Cost + Variable Cost Conventional < Fixed Cost + Variable Cost • Calculated - Earnings (S – COS – D – taxes) - Annual Cash Flow - Net Present Value @ 15% - Cash Flow Discounted To Present Worth - Sum of Discounted Cash Flows = NPV

Bottom Line • NPV Calculated Over 15 Years • 2015: NPV for Scheme II is 2. 5 $MM greater than Scheme I

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

Acknowledgments Professor Wallman Professor Lynn