Ujian Rumah - TK4101 - Smt I 2015-2016

TK4101 Perancangan Proses Kimia Ujian Akhir Terbuka : Batas Waktu :

Tiga topik perancangan proses. Jumat, 18 Desember 2015.

Soal #1 (Nilai 50%) + Bonus Semangat Berkreasi : Anda sedang ditugasi untuk mengkaji proses produksi iso-butan berdasarkan reaksi kesetimbangan berikut:

Umpan proses ini adalah aliran dengan komposisi 20 %-mol iso-butan dan 80 %-mol normalbutan. Secara khusus, anda diminta mengkaji dua alternatif konfigurasi proses tipikal yang melibatkan operasi unit distilasi dan reaktor seperti digambarkan pada skema skema proses berikut:

Laporan hasil kajian anda diharapkan mencakup dua hal utama berikut: 1. Penjelasan naratif hasil evaluasi keunggulan dan kelemahan dari masing-masing konfigurasi proses. 2. Evaluasi kuantitatif tekno-ekonomi untuk menentukan pilihan dari salah satu konfigurasi tersebut. Catatan : Anda sangat dianjurkan mencari tambahan informasi yang diperlukan (misal: kinetika reaksi, kondisisi operasi tipikal, pelibatan integrasi panas, dll).

Soal #2 (Nilai 50%) + Bonus Semangat Berkreasi : A material balance has been completed for a process to manufacture styrene and an ethylbenzene ethylbenzene byproduct from reactions involving methanol and toluene. See Figure below f or a block flow diagram of the process p rocess with the results of material balance calculations.

Ujian Akhir Terbuka TK4101 Perancangan Proses Kimia

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You are to develop an optimal heat exchanger network for this process. Note that: a) Stream 1 is fresh methanol feed, which enters at 25 C and 600 Pa. b) Stream 2 is fresh toluene feed, which enters at 25 C and 600 Pa. c) Stream 4 is methanol vapor recycle from the aqueous methanol recovery, S3, system. This stream returns at 113 C at saturation pressure. d) Stream 3 is an organic recycle from the distillation section. This stream returns at 175'C and saturation pressure as a vapor. e) Streams 1 and 2 must be brought to the bubble point in separate heat exchangers and then vaporized in separate heat exchangers. These streams can then be mixed as desired with streams 3 andlor 4 to obtain the combined feed to the reactor, which must enter the reactor at 500 C and 400 kPa. A furnace must be used to heat streams from 400 to 500 C. f) Stream 6, the reactor effluent, leaves the adiabatic reactor as vapor at 425 C and 330 kPa and must be cooled and partially condensed at 278 kPa before entering the three-phase separator. During that condensation, primary and secondary dew points are observed, with the final effluent comprised of a vapor phase and two liquid phases. Be sure to determine a cooling curve for cooling and partially condensing the reactor effluent. g) Column S1 has a reboiler duty of 2.83 X 107  kcal/hr to reboil the bottoms in the temperature range of 144-145 C. h) Column S2 has a reboiler duty of 4.64 X 10 6 kcal/hr to reboil the bottoms in the temperature range of 153-154 C. i) Column S1 needs a condenser duty of 2.59 X 10 7  kcal/hr to condense the overhead in the temperature range of 103-80 C. j) Column S2 needs a condenser duty of 2.62 X 10 6  kcaVhr to condense the overhead in the temperature range of 108-89 C. k) Stream 11, the liquid styrene product, needs to be cooled from 145 to 38 C before being sent to storage. l) Stream 13, the liquid ethylbenzene byproduct, needs to be cooled from 153 to 38 C before being sent to storage. Your tasks: 1. Solve the material and energy balances for the flowsheet in the Figure above using a process simulator. Adjust the pressure drops in each equipment item to satisfy the pressure specifications above. 2. Using the solution of the material and energy balances in step 1, extract information necessary to define the HEN synthesis problem. Pay attention to possible phase changes in the streams. 3. Compute the pinch temperatures and MER targets for Tmin = 10°C. 4. Carry out an MER design to meet the targets in step 3. Avoid temperature-driving forces greater than 50°C when boiling a pure species or a mixture.  ____________________________

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Ujian Akhir Terbuka TK4101 Perancangan Proses Kimia

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