Plantwide Control Design For Gas Processing Facility (Gpf) Plant

Penggunaan energi hidrokarbon saat ini masih sangat dominan, dimana energi hidrokarbon yang paling efisien adalah gas alam. Agar gas alam dapat digunakan dengan baik, maka harus diproses terlebih dahulu pada suatu plant untuk dihilangkan kandungan H2S, CO2, dan H2O yang disebut Gas Processing Facility (GPF). GPF terbagi dua unit yaitu H2S Removal System dan TEG Dehydration Unit. Adanya material recycle, integrasi panas serta produksi gas alam yang tidak selalu stabil menjadi permasalahan dalam GPF ini, sehingga pengendalian proses plant yang kompleks dibutuhkan dalam menyelesaikan permasalahan ini. Perancangan desain plantwide control (PWC) pada GPF berhasil menyelesaikan permasalahan tersebut, terbukti dengan adanya analisis dampak dari sisi energi, ekonomi dan dari kestabilan plant. Metode PWC yang digunakan menurunkan metode milik Luyben dan Skogestad. Hasil perancangan PWC pada kenaikan feed 5% mampu menurunkan penggunaan energi sebesar 52.37 kJ perjam dan mampu meningkatkan profit sebesar 360 U$ perhari sedangkan pada penurunan feed sebesar 5% mampu menurunkan penggunaan energi sebesar 61.38 kJ perjam dan mampu meningkatkan profit sebesar 491 U$ perhari. Penerapan PWC juga dapat menghasilkan respon sistem yang stabil saat dilakukan uji gangguan dibuktikan dengan settling time dan overshoot yang menurun serta eror steady state yang hilang dibandingkan dengan pengendalian PID saja sebelum dilakukan perancangan PWC. Kata Kunci : Plantwide control, gas processing, kontrol proses ================================================================================================= Hydrocarbons energy is currently still very dominant, where the most efficient hydrocarbon energy is natural gas. So that natural gas can be used properly, it must be processed first at a plant for the removed content of H2S, CO2, and H2O that called a Gas Processing Facility (GPF). GPF is divided into two units namely H2S Removal System and TEG Dehydration Unit. The existence of material recycle, heat integration, and unstable production of natural gas from well became problems in this GPF, so a complex process control required in resolving this problem. Designing plantwide control (PWC) on the GPF successfully completed these problems, as evidenced by the existence of impact analysis from the energy, the economy and the stability of the plant. PWC method that used in this final project compere Luyben and Skogestad method. The results of the design of PWC at a 5% increase in feed is capable of lowering the energy use of 52.37 kJ perhour and able to improve profit in the amount of U $360 per day, while in a 5% decrease in feed is capable of lowering the energy use of 61.38 kJ perhour and able to increase profit in the amount of U $491 per day. Application of PWC can also generate a stable system response with disturbance test, with evidence can decrease settling time and overshoot and omit steady state error compared control PID just before the redesign PWC. Keywords : Plantwide Control (PWC), Gas Processing, Process Contro