Evaporator Optimization Project Bryan Picou James Roberts Advisor
Evaporator Optimization Project Bryan Picou James Roberts Advisor: Dr. Junkun Ma ET 493 Instructor : Dr. Cris Koutsougeras
Domino Sugar �Refinery is in Arabi, La �Produce 8 million pounds of sugar per day on average �It is the third largest sugar refinery in the world
Domino Sugar
Evaporator Optimization Project �Steam is one of the most expensive resources for a refinery • Take the current operation of the evaporators and make it more efficient • Take the current operation of the melters and eliminate the steam
Evaporators � Evaporator uses steam in a vacuum to heat the sugar liquor and lower its density � Left over vapors from this process is what we are trying to optimize
Melter �Takes the raw sugar and uses steam to melt this sugar into a liquid. �It uses direct steam injection �Vapors from evaporator will be rerouted to power the melter
Current Operation
Current Operation
Sugar Parameters �Based upon 8 million pound melt rate � 8 % scrap rate �Sugar going into melters assuming 70 Brix
Sketch of New Operation
Energy required to Melt Sugar �Q = Cp of Sugar at 70 Bx* Mass of Sugar * ΔTemperature �Cp = 0. 65 BTU/lb F �Mass of Sugar at 70 Bx and 8 % scrap rate = 478, 800 lb/hr �Ti = 130 F Tf = 170 F �ΔT = 40 F �Q = 12, 448, 800 BTU/hr
Energy in Steam With Phase Change �Q = Mass of Steam * Latent Heat of Steam �Latent Heat of Steam = 976. 6 �Mass of the Steam = 18, 100 lb/hr �Q = -17, 676, 460 BTU/hr
Barometric Condenser
Condenser Design �Qsteam = Qsugar �Mass of Steam * Latent Heat of Steam = Cp of Sugar * Mass of Sugar * ΔTemperature �Rearranging: �Mass Steam = (Cp of Sugar * Mass of Sugar * Δtemperature)/Latent Heat of Steam
Condenser Design �Mass of Steam = (0. 65 * 478, 800 * 40)/976. 6 �Mass of Steam = 12, 747. 08 lb/hr
Energy in Steam without Phase Change �Q = Cp of Steam * Mass of Steam * ΔTemperature �Cp = 0. 45 BTU/lb F �Mass of Steam = 5, 353 lb/hr �Ti = 188. 5 F Tf = 170 F �Q = -44, 563. 045 BTU/hr
Energy in Steam with Phase Change �Q = Mass of Steam * Latent Heat of Steam �Latent Heat of Steam = 976. 6 �Mass of the Steam = 12, 747 lb/hr �Q = -12, 448, 800 BTU/hr
Total Energy Going to Melters �Qsteam without phase change + Qsteam with phase change �Qtotal = -12, 493, 363 BTU/hr
Steam Pipeline Design �Volumetric Flow Rate = Velocity * Area �Velocity = Volumetric Flow Rate/Area �Volumetric Flow Rate of Steam = 18, 100 * 47. 344 = 856, 926. 4 ft 3/hr �Area of 16 in pipe = 1. 396 ft 2 �Velocity = 856, 929. 4 ft 3/hr / 1. 369 ft 2 = 170. 56 ft/s
Condenser Design (Sugar) �Mass of Sugar = (Mass of Steam being condensed * Latent Heat of Steam) / Latent Heat of Sugar �Enthalpy of Sugar at 70 Bx and at 188. 5 F = 82. 47 BTU/lb �Mass of Sugar = 150, 949. 436 lb/hr
Sugar Pipeline Design �Volumetric Flow Rate = Velocity * Area �Velocity = Volumetric Flow Rate/Area �Volumetric Flow Rate of Sugar = 150, 949. 436 * (1/92. 2) = 1637. 196 ft 3/hr �Area of 4 in pipe = 0. 0872 ft 2 �Velocity = 5. 214 ft/s
Pressure Loss in Steam Pipeline �Head Loss = friction factor * (Length/Diameter) * (Velocity 2/ 2*gravity) �HL = 0. 015 * (377. 95 ft/ 1. 33 ft)*((170. 567 ft/s)2/ (2*32. 2 ft/s 2)) �HL = 1920. 83 ft
Pressure Loss in Steam Pipeline �Bernoulli’s Equation: � P 1 + Z 1 + V 12 - H L = P 2 + Z 2 + V 22 Υ 2 g �Rearranged � P 2 = [(P 1/Υ)-HL * Υ] �P 2 = [(8 * 144) – (1920. 83 * 0. 0193)] �P 2 = 7. 743 psi
Residence Time �λ= Volume of Melter / Volumetric Flow Rate �Volume of Melter = 329. 867 ft 3 �Volumetric Flow Rate = 2168. 675 ft 3/hr �λ= 9. 13 min
Sugar Dissolution Lab Sugar Dissolution 200 R 2 = 0. 9394 180 160 Temperature (F) 140 120 100 Temp (°F) Power(Temp (°F)) 80 60 40 20 0 0 5 10 15 20 25 Time (min) 30 35 40 45
Melter with 10 % increase in Volume �λ= Volume of Melter / Volumetric Flow Rate �Volume of Melter = 400. 553 ft 3 �Volumetric Flow Rate = 2168. 675 ft 3/hr �λ= 11. 082 min
Deliverables � Sketch of future operation (Nov) � Energy of vapors (Nov) � Vapor Flow Rate (Nov) � Energy Required to melt sugar (Nov) � Residence time of melters (Dec) � Design new melter (Dec) • Designing the new melters based on energy requirements and availability � Design condenser (Dec) • Flow Rates, Pressure and Temperature Differences • Energy Transfer
Deliverables �Design • • Vapor and liquor Pipeline (Dec) Determine pipe size Stress Analysis Material Selection Minimize Energy Loss �Design Heat Exchangers (Feb) • Size of Heat Exchangers • Materials of Heat Exchangers • Energy Transfer
Deliverables �Design Pipeline Support Structure • Deflection • Stress Analysis on Structure • Distance between supports • Material Selection �COMSOL (March) • Pipeline stress analysis • Structural Support Stress Analysis • Pipeline Deflection • Beam Deflection (Feb)
Deliverables �Design New System Layout (March) • ACAD Sketch • Instruments Selection • Space Requirements �Control Sequence (April) • Safety • Ladder Logic (PLC)
Deliverables �Cost Analysis (April) • Yearly savings from cutting down steam consumption �Project Cost (April) • Cost of New Materials and Machines • Cost of a Contractor installing all Materials and Machines
James Project Responsibilities �Sketch of Future Operation �Energy Required to Melt Sugar �Residence Time �Design Melters �Design Sugar Liquor Pipeline �Design Structural Support System �COMSOL �Design New System Layout �Control Sequence
Bryan’s Project Responsibilies �Sketch of Future Operation �Energy of Vapors �Vapor Flow Rate �Design Condenser �Design Vapor pipeline �Design Heat Exchanger �COMSOL �Design New System Layout �Cost Analysis, Project Cost Analysis
References �Domino Sugar Corporation �Cane Sugar Refining Handbook �www. sugartech. co. za
- Slides: 34