ANALISIS TERMODINAMIKA SIKLUS RANKINE COGENERATION PADA STEAM POWER PLANT - UTILITIES AREA 05 BESERTA PERHITUNGAN UNJUK KERJA KOMPONEN UTAMANYA (STUDI KASUS DI PT PERTAMINA REFINERY UNIT IV CILACAP)

ABELIO FEBRYAN SUHARDI, Prof. Dr. -Ing. Ir. Harwin Saptoadi, M.SE

2017 | Skripsi | S1 TEKNIK MESIN

Pada Tugas Akhir ini, penulis melakukan analisis termodinamika Siklus Rankine pada PLTU (Steam Power Plant) milik PT Pertamina (Persero) Refinery Unit IV Cilacap. Siklus Rankine yang dipakai adalah Siklus Rankine Cogeneration, yang menghasilkan dua macam useful energy berupa energi listrik dan process heat. Bahan bakar boiler menggunakan campuran fuel oil & fuel gas. Adapun penelitian ini bertujuan untuk mengetahui utilization factor dari Cogeneration Power Plant dan juga menganalisa performa dari komponen utama Power Plant (boiler, turbin uap, kondenser, dan pompa). Penelitian ini dilakukan dengan melakukan studi literatur dari berbagai sumber serta survey lapangan kondisi power plant terlebih dahulu di Utilities Area 05. Kemudian dilakukan pengambilan data properties yang dibutuhkan untuk melakukan analisis dan perhitungan. Data-data tersebut diperoleh dari Control Room 05, pengamatan langsung di lapangan, specification sheet milik perusahaan, dan juga wawancara dengan engineer perusahaan. Setelah data terkumpul lengkap, dilakukan analisis utilization factor dari Cogeneration Power Plant beserta perhitungan unjuk kerja komponen utamanya. Dari hasil analisis dan perhitungan didapatkan nilai utilization factor rata-rata dari Cogeneration Power Plant di Utilities Area 05 pada 10 macam pembebanan aktual (Wact) sebesar 63,44 %. Nilai efisiensi rata-rata boiler 052B102 pada tanggal 19 Mei 2017 sebesar 83,58 %. Nilai efisiensi rata-rata turbin uap 051TG101 pada 10 macam pembebanan aktual sebesar 80,66 %. Nilai efektivitas surface condenser 051E101 sebesar 99,5 %. Nilai efisiensi high pressure - boiler feedwater (HP-BFW) pump sebesar 72,38 %. Faktor-faktor yang mempengaruhi nilai utilization factor antara lain pressure, temperatur, dan mass flow rate dari High Pressure Steam (HPS), Medium Pressure Steam (MPS), dan Condensate ; daya listrik yang dihasilkan oleh turbin uap ; jumlah dan kapasitas pompa yang digunakan ; process heat yang dihasilkan ; dan energi kalor input yang masuk ke dalam boiler. Adapun metode yang dapat dilakukan untuk meningkatkan nilai utilization factor dari Cogeneration Power Plant adalah dengan mencari metode yang akurat dan efisien untuk mendeteksi serta mengurangi rugi-rugi energi pada sistem ; melakukan penyesuaian nilai mass flow rate, pressure, dan temperatur dari High Pressure Steam (HPS), Medium Pressure Steam (MPS), dan Condensate ; serta melakukan maintenance dari komponen-komponen penyusun Power Plant secara berkala sesuai prosedur yang berlaku.

A thermodynamic analysis of Rankine Cycle was conducted at Steam Power Plant, PT Pertamina (Persero) Refinery Unit IV Cilacap. Rankine Cycle that used in the company is Cogeneration Rankine Cycle, that producing two kinds of energy : electricity power and process heat. Boiler's fuel are mixture of fuel oil and gas. This research aimed to investigate the utilization factor from Cogeneration Power Plant and analyzing the primary component's performance of Power Plant (boiler, steam turbine, condenser, and pump). The first steps of this research were a literature study from many sources and field surveying of power plant condition at Utilities Area 05. Then, the data acquisitions for some properties that required for analysis and calculations. Those datas were acquired from Control Room 05, field observations, company's specification sheets, and also did some interviews with company's engineer. After the data were collected completely, the analysis of utilization factor of Cogeneration Power Plant with the calculations of its primary components was obtained. As a result, the average value of utilization factor 63,44 % at ten kinds of actual loads. The average boiler 052B102's efficiency at May, 19th 2017 was 83,58 %. The average efficiency of the steam turbine 051TG101 is 80,66 % at ten kinds of actual load. The effectiveness of the surface condenser 051E101 is 99,5 %. The efficiency of the high pressure - boiler feedwater (HP-BFW) pump is 72,38 %. Some factors that affected the utilization factor value, among others are pressures, temperatures, and mass flow rates of High Pressure Steam (HPS), Medium Pressure Steam (MPS), and Condensate ; the electricity powers produced by the steam turbines ; amount and capacity of the pumps ; process heat produced ; and also input energy that enter the boilers. As for, methods that can be undertaken to improving utilization factor value of the Cogeneration Power Plant are : finding methods that accurately and efficiently can detect and reduct energy losses in the system ; adjusting the value of mass flow rates, pressures, and temperatures of High Pressure Steam (HPS), Medium Pressure Steam (MPS), and Condensate ; and also maintaining the constituent components of power plant periodically following the applicable procedures.

Kata Kunci : Cogeneration, Steam Power Plant, Utilization Factor, Efisiensi, Boiler, Turbin Uap, Surface Condenser, HP BFW Pump