Hasil Pencarian  ::  Simpan CSV :: Kembali

"Penelitian ini menganalisa penyebab patahnya blade turbin uap dari pembangkit listrik tenaga uap Suralaya yang berbahan dasar baja karbon Cr 12. Blade turbin uap ini telah digunakan selama 33 tahun. Hasil analisis dapat dijadikan bahan pertimbangan dalam proses peremajaan bahan yang akan dilakukan pada tahap penelitian selanjutnya. Komposisi utama dari paduan baja karbon ini adalah Fe dan Cr. Kandungan Fe dan Cr pada patahan divalidasi dengan melakukan uji x-ray fluorescence. Hasil uji ini komposisi menunjukkan kandungan Fe dan Cr masing-masing sebesar 73.07 dan 16.11 wt%. Kandungan Fe lebih rendah sedangkan Cr lebih tinggi pada patahan dibandingkan dengan nilai referensi bahan standar. Uji mekanik yaitu uji tarik dan uji kekerasan dilakukan untuk mengidentifikasi perilaku deformasi patahan. Hasil uji tarik menunjukkan bahwa patahan mengalami penurunan kekuatan tarik sebesar 5x dengan batas luluh 3x lebih rendah dari nilai referensi bahan standar. Uji kekerasan menunjukkan peningkatan kekerasan jika dibandingkan dengan referensi bahan standarnya, sedangkan nilai regangannya masih dibatas normal. Hasil uji x-ray diffraction (XRD) dengan membandingkan bahan patahan dengan bagian yang utuh menunjukkan tidak ada perbedaan yang signifikan pada komposisi fasa bahan. Ketiga titik analisis mengandung fasa utama yaitu Fe-α. Hasil SEM dan mikroskop optik menunjukkan pola retakan yang terjadi akibat kelelahan yang kemungkinan ditandai dengan beachmarks dan adanya intergranular crack serta terdapat banyak void. Penyebab retakan ini sudah sangat sering terjadi dan merupakan masalah terbesar dalam turbin uap. Hasil uji fatigue menunjukkan penyebab lain dari retakan yaitu kelelahan. Disarankan proses peremajaan melibatkan peleburan ulang atau pemanasan suhu tinggi.

---

ABSTRACTThis research analyzes the cause of the broken steam turbine blade from the Suralaya steam power plant based on Cr 12 carbon steel. This steam turbine blade has been used for 33 years. The results of the analysis can be taken into consideration in the process of rejuvenation of the material to be carried out at the next research stage. The main composition of this carbon steel alloy is Fe and Cr. The content of Fe and Cr in the fracture was validated by conducting an x-ray fluorescence test. The results of this test showed that the composition of Fe and Cr was 73.07 and 16.11 wt%, respectively. The Fe content is lower where as Cr is higher in the fracture compared to the reference value of standard materials. Mechanical tests namely tensile tests and hardness tests are carried out to identify the fault deformation behavior. Tensile test results show that the fracture has decreased the strength of the blade by 5x with a yield limit of 3x lower than the reference value of standard materials. Hardness test shows an increase in hardness when compared to the reference standard material, while the strain value is still normal. The results of the x-ray diffraction (XRD) test by comparing the fractured material with the intact part showed no significant difference in the phase composition of the material. The three points of analysis contain the main phase, Fe-α. The results of SEM and optical microscopy show crack patterns that occur due to fatigue that may be marked by beachmarks and the presence of intergranular cracks and there are many voids. The cause of these cracks is very common and is the biggest problem in steam turbines. Fatigue test results show another cause of cracking, which is fatigue. It is recommended that the rejuvenation process involve re-smelting or high-temperature heating."

"Kegagalan material pipa boiler yang disebabkan oleh berbagai jenis korosi akan mengakibatkan unit pembangkit berhenti beroperasi, sehingga menimbulkan kerugian yang besar sebagai akibat produksi listrik yang terhenti. Hal ini pernah terjadi pada material pipa SA-210 Grade A1 di Boiler furnace wall tube PLTU Suralaya 8 yang mengalami korosi hydrogen damage. Penelitian ini ditujukan untuk menganalisa proses korosi hydrogen damage sampel material pipa SA-210 Grade A1. Pengujian terdiri dari analisis struktur mikro, uji mekanis, serta laju dan produk korosi yang dihasilkan. Pada analisis struktur mikro ditemukan banyak kavitas pada material. Pada uji mekanis didapatkan penurunan hardness, tensile strenght, yield strength, dan elogation. Pada analisis laju korosi didapatkan nilai 0,01-0,074 mm/tahun. Analisis XRD menunjukkan bahwa terdapat kandungan korosi berupa magnetite, hematite dan wustite. Dari hasil berbagai analisis dan uji pada material tersebut disimpulkan terjadi proses korosi hydrogen damage yang masih berlangsung hingga saat ini.

---

Boiler tube material failure caused by various types of corrosion will lead to power plant shutdown, consequently causing great loss as a result of halted electicity generation. It was happened to the tube material SA-210 Grade A1 in the boiler furnace wall tube Suralaya 8 that experiencing hydrogen damage corrosion. This study aimed to analyze the hydrogen damage corrosion process of tube SA-210 Grade A1 material sample. The analysis consisted of microstructure analysis, mechanical properties analysis, also corrosion rate and products analysis. The microstructure analysis found many cavities in the material. The mechanical properties analysis found a decrease in hardness, tensile strenght, yield strength, and elogation. The corrosion rate obtained from 0.01 to 0.074 mm/year. XRD analysis showed the content of corrosion in the form of magnetite, hematite and wustite. From the results of various analyzes and tests on the material, we concluded a hydrogen damage corrosion process was happened and still continues until today."

"ABSTRAKPolutan utama dari sistem pembakaran batubara salah satunya SO2. Sulfur dioksidia menyebabkan iritasi, batuk refleks, menyebabkan penyakit pernafasan dan gangguan daya tahan paru-paru. Penelitian ini bertujuan menganalisis pajanan SO2 di lingkungan sekitar pembangkit listrik tenaga uap (PLTU) Suralaya yaitu pada desa Lebak Gede, Cipala Dua, Brigil, Gunung Gede, Salira Indah, dan Sumuranja dan gangguan pernafasannya pada masyarakat sekitar. Penelitian ini bersifat deskriptif, dengan pendekatan cross sectional. Sampel responden diambil secara purposive sampling berdasarkan titik pengukuran udara pada setiap desa yaitu 35 orang di setiap desa. Penelitian ini dilakukan dengan metode Analisis Risiko Kesehatan Lingkungan (ARKL) yang menggunakan nilai Rfc SO2 (0,026 mg / kg / hari), dan selanjutnya dilakukan secara cross sectional untuk menghubungkan tingkat risiko dengan kejadian gangguan pernafasan di sekitar PLTU. Hasil ARKL menunjukkan bahwa tingkat risiko di lingkungan sekitar PLTU Suralaya yaitu pada desa Lebak Gede, Cipala Dua, Brigil, Gunung Gede, Salira Indah, dan Sumuranja masih tergolong aman karena nilai RQ dibawah 1 dalam kurun waktu lebih dari 30 tahun. Hasil analisis cross sectional menunjukkan bahwa tidak ada hubungan antara tingkat risiko kesehatan akibat pajanan SO2 dengan kejadian gangguan saluran pernafasan pada masyarakat di sekitar PLTU karena memiliki nilai-p yang lebih besar dari alfa.ABSTRACTOne of the main pollutants from the coal combustion system is SO2. Sulfur dioxidia causes irritation, reflex coughing, causes respiratory disease and lung resistance. This study aims to analyze SO2 exposure in the environment around the Suralaya steam power plant (PLTU), namely in the villages of Lebak Gede, Cipala Dua, Brigil, Gunung Gede, Salira Indah, and Sumuranja and respiratory problems in the surrounding community. This research is descriptive, with a cross sectional approach. The sample of respondents was taken by purposive sampling based on air measurement points in each village, namely 35 people in each village. This research was conducted using the Environmental Health Risk Analysis (ARKL) method using the Rfc SO2 value (0.026 mg / kg / day), and then carried out cross-sectional to link the risk level with the incidence of respiratory problems around the PLTU. The ARKL results show that the level of risk in the environment around PLTU Suralaya, namely in the villages of Lebak Gede, Cipala Dua, Brigil, Gunung Gede, Salira Indah, and Sumuranja is still relatively safe because the RQ value is below 1 in a period of more than 30 years. The results of the cross sectional analysis show that there is no relationship between the level of health risk due to SO2 exposure and the incidence of respiratory problems in the community around the PLTU because it has a p-value greater than alpha."

"ABSTRAKPenelitian ini difokuskan pada studi degradasi material tube boiler secondary superheater (SSH) pada pembangkit listrik. Material baja karbon rendah 2.25Cr-1Mo mengalami kerusakan retak terbuka selang 26 jam setelah tes ujicoba. Material yang mengalami kerusakan, dianalisis secara fisik dan mekanik menggunakan uji metalografi, uji komposisi kimia, Scanning electon microscopy- Energy Dispersive X-ray Spectroscopy (SEM-EDX), uji kekerasan dan uji tarik, kemudian dibandingkan dengan material baru dan lama. Struktur mikro tube rupture mengalami elongasi searah keliling lingkaran tube dan retak mikro pada batas butir mengindikasikan adanya tegangan yang melebihi kemampuan material.Hasil perhitungan tegangan (hoop stress) sebesar 42,47 MPa, melebihi nilai yang diijinkan sebesar 23,5 MPa pada maksimum temperatur metal tube 605 °C. Material mengalami degradasi saat tercapai temperatur tertinggi (overheating), dan terjadi dalam waktu singkat. Pada tube lama, degradasi terjadi karena perubahan struktur mikro perlit menjadi speroidisasi karbida yang terdekomposisi dan terdispersi pada matrik ferit. Perubahan ini terjadi karena material terekspos dalam rentang waktu lama pada lingkungan temperatur tinggi.

---

ABSTRACT

This research focused on the study of material degradation of tube boiler secondary superheater (SSH) in power plant. Low carbon steel 2.25Cr-1Mo are wide open ruptured in 26 hours after the running test. Samples were analyzed with physical and mechanical tests using metallographic, chemical composition, scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDX), hardness and tensile test and compared with virgin and old tube. Microstructure of rupture tube undergo elongation direction of the circumference tube and micro cracks at grain boundaries indicates a stress that exceeds the ability of the material.

The stress calculations (hoop stress) of 42.47 MPa, exceeding the allowable stress of 23.5 MPa at maximum metal tube temperature of 605 °C. In the old tube, degradation occurs due to changes in the microstructure into pearlite spheroidizing carbides are decomposed and dispersed in the ferrite matrix. This change occurs because the material is exposed in a long time at high temperature environment."

"[ABSTRAKListrik adalah kebutuhan pokok untuk kegiatan dan aktivitas manusia, terutama untuk kegiatan ekonomi. PLTU Suralaya adalah PLTU berbahan bakar batubara, yang mempunyai kapasitas untuk menghasil listrik yang murah namun juga menghasil polusi yang besar juga. PLTU Suralaya menghasilkan listrik yang digunakan untuk seluruh penduduk yang terhubung pada jaringan Jawa, Madura dan Bali, namun polusi udara yang dihasilkan memiliki perilaku-perilaku tertentu dan berdampak pada penduduk di sekitar PLTU Suralaya. Atas dasar dari deskripsi tersebut, tujuan dari penelitian ini adalah menganalisis perilaku spasial polusi udara yang terbentuk dan efek apa saja yang dialami penduduk yang berdomisili di sekitar PLTU Suralaya. Dalam penelitian ini, untuk menentukan polusi udara menggunakan zat SO2 sebagai indikatornya. Metode yang dilakukan dalam penelitian ini adalah metode pemetaan dan pengolahan citra satelit, survey, dan wawancara.Perilaku Spasial pencemaran polusi udara terbentuk 4 fase, yakni : fase I (musim penghujan), fase II (musim peralihan kemarau), fase III (musim kemarau), dan fase IV (musim peralihan hujan). Perilaku spasial pencemaran polusi udara tahun 2005 adalah mengikuti pola pergerakkan angin muson. Sedangkan perilaku spasial pencemaran polusi udara tahun 2014 memiliki pergerakkan dari barat menuju timur. Efek dari polusi polusi udara tidak dirasakan oleh PLTU Suralaya, namun efeknya dirasakan di area lain yakni Kota Cilegon

---

ABSTRACTElectricity is a basic need for human activity, mainly for economic activities. PLTU Suralaya is a coal-fired power plant, which has the capacity to produce cheap electricity but also generate substantial pollution as well. PLTU Suralaya generate electricity that is used for the entire population residing in Java, Madura and Bali, but the resulting air pollution have spatial behaviors and the impacts on residents around Suralaya. On the basis of this description, the purpose of this study is to analyze the spatial behavior of air pollution is formed and any effects experienced by people who live around Suralaya. In this research, SO2 will be used for indicator as air pollution. The method used in this research is a method of mapping and satellite image processing, surveys, and interviews.Spatial Behavior of air pollution formed four phases, namely: Phase I (rainy season), phase II (intermediate dry season), Phase III (dry season), and phase IV (transition rainy season). Spatial behavior of air pollution in 2005 was followed the movement pattern of the monsoons. While the spatial behavior of air pollution in 2014 has movement from west to east. Effects of air pollution is not felt by residents in Suralaya, but the effect is felt in other areas of the Cilegon;Electricity is a basic need for human activity, mainly for economic activities. PLTU Suralaya is a coal-fired power plant, which has the capacity to produce cheap electricity but also generate substantial pollution as well. PLTU Suralaya generate electricity that is used for the entire population residing in Java, Madura and Bali, but the resulting air pollution have spatial behaviors and the impacts on residents around Suralaya. On the basis of this description, the purpose of this study is to analyze the spatial behavior of air pollution is formed and any effects experienced by people who live around Suralaya. In this research, SO2 will be used for indicator as air pollution. The method used in this research is a method of mapping and satellite image processing, surveys, and interviews.Spatial Behavior of air pollution formed four phases, namely: Phase I (rainy season), phase II (intermediate dry season), Phase III (dry season), and phase IV (transition rainy season). Spatial behavior of air pollution in 2005 was followed the movement pattern of the monsoons. While the spatial behavior of air pollution in 2014 has movement from west to east. Effects of air pollution is not felt by residents in Suralaya, but the effect is felt in other areas of the Cilegon, Electricity is a basic need for human activity, mainly for economic activities. PLTU Suralaya is a coal-fired power plant, which has the capacity to produce cheap electricity but also generate substantial pollution as well. PLTU Suralaya generate electricity that is used for the entire population residing in Java, Madura and Bali, but the resulting air pollution have spatial behaviors and the impacts on residents around Suralaya. On the basis of this description, the purpose of this study is to analyze the spatial behavior of air pollution is formed and any effects experienced by people who live around Suralaya. In this research, SO2 will be used for indicator as air pollution. The method used in this research is a method of mapping and satellite image processing, surveys, and interviews.Spatial Behavior of air pollution formed four phases, namely: Phase I (rainy season), phase II (intermediate dry season), Phase III (dry season), and phase IV (transition rainy season). Spatial behavior of air pollution in 2005 was followed the movement pattern of the monsoons. While the spatial behavior of air pollution in 2014 has movement from west to east. Effects of air pollution is not felt by residents in Suralaya, but the effect is felt in other areas of the Cilegon]"

"Dalam melayani sebuah sistem kelistrikan dibutuhkan pembangkit yang handal dan efisien. Pembangkit Listrik Tenaga Gas Uap PLTGU merupakan salah satu pilihan pembangkit thermal yang mempunyai kriteria tersebut. Terdapat beberapa jenis konfigurasi PLTGU. Khusus untuk PLTGU dengan dua turbin gas memliki dua jenis konfigurasi, yaitu konfigurasi 2G-2H-3S dua turbin gas, dua HRSG, tiga turbin uap dan konfigurasi 2G-2H-1S dua turbin gas, dua HRSG, satu turbine uap . Mode operasi dari setiap jenis konfigurasi menghasilkan keandalan dan efisiensi yang berbeda.Penelitian ini bertujuan untuk menghitung efisiensi dan keandalan dari dua jenis konfigurasi PLTGU yang menggunakan dua turbin gas, sehingga dapat menentukan pengaruh jenis konfigurasi terhadap efisiensi dan keandalan PLTGU. Dengan menggunakan metode energi input ouput untuk menentukan besar efisiensi dan dengan menghitung Equivalent Availability Factor EAF untuk mendapatkan faktor kesiapan atau keandalan pembangkit.Dari hasil perhitungan didapatkan konfigurasi 2G-2H-1S memliki nilai efisiensi yang lebih tinggi dari konfigurasi 2G-2H-3S, terhitung Untuk mode operasi Full Blok Cycle konfigurasi 2G-2H-1S memliki efisiensi maksimum 55.5 sedangkan konfigurasi 2G-2H-3S efisiensi maksimum 53.5 . Sedangkan untuk nilai keandalan konfigurasi 2G-2H-3S lebih handal dibandingkan dengan konfigurasi 2G-2H-1S. Untuk mode operasi Full Blok Cycle memliki 93.39 EAF, sedangkan konfigurasi 2G-2H-3S 92.62 EAF. Dari segi keekonomian kedua jenis konfigurasi memiliki nilai kelayakan, dimana untuk konfigurasi 2G-2H-1S lebih ekonomis dilihat dari NPV 371,286,536 USD dan IRR 12 serta waktu pengembalian modal yang relative lebih cepat 9 tahun. Dengan mengetahui konfigurasi PLTGU yang handal, efisien dan ekonomis dapat dijadikan dasar pengambilan keputusan untuk pemilihan konfigurasi PLTGU yang sesuai dengan kebutuhan beban dasar, beban menengah, atau beban puncak di sebuah sistem kelistrikan.Kata Kunci : EAF, Efisiensi, Keandalan, Konfigurasi PLTGU, PLTGU.

---

In serving the electrical systems required a reliable and efficient plants. Combined Cycle Power Plant CCPP is one of the thermal power plants that have a selection criteria. There are several types of CCPP configurations. Especially for CCPP with two gas turbines have two types of configurations, the configuration of 2G 2H 3S two gas turbines, two HRSG, three steam turbines and the configuration of 2G 2H 1S two gas turbines, two HRSG, one steam turbine , The mode of operation of each type of configuration produces a different reliability and efficiency.

This study aimed to quantify the efficiency and reliability of two types of power plant configuration that uses two gas turbines, so as to determine the effect of this type of configuration on the efficiency and reliability of the CCPP. By using the input energy ouput to determine the efficiency and to calculate Equivalent Availability Factor EAF to obtain readiness factors or reliability of the power plant. From the results of the calculation.

Calculation resulting from the configuration of 2G 2H 1S has a higher efficiency values of configuration 2G 2H 3S, accounting for full block cycle operating modes configuration 2G 2H 1S discount maximum efficiency of 55.5 , while the configuration of 2G 2H 3S efficiency a maximum of 53.5 . As for the value of reliability configuration 2G 2H 3S is more reliable than the configuration of 2G 2H 1S. For full block cycle operating modes discount EAF 93.39 , while the configuration 2G 2H 3S 92.62 EAF. In terms of economics both types of configurations have a feasibility value, which for configuration 2G 2H 1S more economical views of NPV 371,286,536 USD and IRR 12 and the payback time is 9 years faster. By knowing the configuration of a reliable, efficient and economical power plant can be used as a basis for a decision on the selection of CCPP configurations in accordance with based load, medium load, or peak load requirements in an electrical system."