Heat Exchanger Network
Heat Exchanger Network Design for the Cumene Process | C.A.K.E. Because We’re Just that Delicious Iowa State University Ames IA, 50010 | Crego, Courtney LHines, KirkMonterrubio, AmyToohey, Erin |
Abstract
Often a major consideration of a chemical process plant is the high cost of utilities used for heating and cooling of process streams. Heat integration of process streams is an effective way to reduce the cost of these utilities, and this process is often referred to as a MUMNE (minimum utility, and minimum number of exchangers) network. In this report three separate heat exchange designs were examined to find the best design in terms of cost. Each design used a different amount of heat integration for the same process streams. Case A used no integration, Case B used all the streams for integration, and Case C only used cold streams 1 and 2, and hot streams 1, 2, 3, and 5 to obtain the same end temperatures for each of the streams given. The specified minimum approach temperature was 15°C.
For each of the three cases, a heat exchange network was designed according to the criteria given in the specified case. Case A included no heat integration and the sizing parameters and cost analysis were done only using utilities. For Case B and Case C, a pinch analysis was performed to properly integrate the process streams. Once the pinch analysis was completed, temperature interval diagrams were drawn on Excel spreadsheets in order to map out the MUMNE network. A HENSAD simulation was a possible computer oriented approach to the design, but the team opted to use other resources instead.
The cost analysis of the three cases was done using the Excel CAPCOST program. This program gave totals for the total capital cost, and total annual utilities cost for each of the three cases. These costs were used to calculate the EAOC (equivalent annual operation cost) using i =5%, and n = 7 years. The EAOC results were Case A ($2,976,213 per year), Case B
Abstract
Often a major consideration of a chemical process plant is the high cost of utilities used for heating and cooling of process streams. Heat integration of process streams is an effective way to reduce the cost of these utilities, and this process is often referred to as a MUMNE (minimum utility, and minimum number of exchangers) network. In this report three separate heat exchange designs were examined to find the best design in terms of cost. Each design used a different amount of heat integration for the same process streams. Case A used no integration, Case B used all the streams for integration, and Case C only used cold streams 1 and 2, and hot streams 1, 2, 3, and 5 to obtain the same end temperatures for each of the streams given. The specified minimum approach temperature was 15°C.
For each of the three cases, a heat exchange network was designed according to the criteria given in the specified case. Case A included no heat integration and the sizing parameters and cost analysis were done only using utilities. For Case B and Case C, a pinch analysis was performed to properly integrate the process streams. Once the pinch analysis was completed, temperature interval diagrams were drawn on Excel spreadsheets in order to map out the MUMNE network. A HENSAD simulation was a possible computer oriented approach to the design, but the team opted to use other resources instead.
The cost analysis of the three cases was done using the Excel CAPCOST program. This program gave totals for the total capital cost, and total annual utilities cost for each of the three cases. These costs were used to calculate the EAOC (equivalent annual operation cost) using i =5%, and n = 7 years. The EAOC results were Case A ($2,976,213 per year), Case B
References: 2) Bartlett, Dean A. "The Fundamentals of Heat Exchangers." The Industrial Physicist (1996): 18-21. Print. 3) Couper, James R. "Short Cut Equipment Design." Chemical Process Equipment: Selection and Design. Burlington, MA: Butterworth-Heinemann, 2010. 187-210. Print. 4) Turton, Richard. Analysis, Synthesis, and Design of Chemical Processes. Upper Saddle River, NJ: Prentice Hall, 2009. Print. 5) Stiehl, C. Project 2 Heat Exchange Network Design for the Cumene Process. Iowa State University at Ames, Spring semester, 2012. 6) "Heat Exchanger Fluid Allocation: Shellside or Tubeside?" Smart Process Design Chemical Engineering Blog. 29 Jan. 2011. Web. 07 Mar. 2012. <http://smartprocessdesign.com/heat-exchanger-fluid-allocation-shellside-tubeside/>.