Norman Subekti | University of Indonesia (original) (raw)

Papers by Norman Subekti

Materials Science Forum, 2018

Eastern-European Journal of Enterprise Technologies, 2020

MAKARA of Technology Series, 2012

The purpose of this research is to investigate the corrosion rate of carbon steel as flowline and... more The purpose of this research is to investigate the corrosion rate of carbon steel as flowline and pipeline in natural gas production with CO 2 content. The influence of variety of conditions that represent the actual conditions in practice such as CO 2 partial pressure and solution composition, particularly NaCl percentage were performed. Research conducted by polarization test and simulation methods using PREDICT TM software. The result of this research is used to illustrate the level of corrosion rate of typical carbon steel i.e. API 5L X-52 occurred in natural gas pipelines due to the effect of dissolved CO 2. From the experiments obtained that corrosion rate of steel in environments containing CO 2 ranged between 15-28 mpy. This high corrosion rate observed could severely damage natural gas transmission flowline and pipeline. The result of this research is the first step, as an input for prevention efforts, to prevent leakage of flowline and pipeline due to corrosion of CO 2 which appropriate with the lifetime that has been designed. Abstrak Laju Korosi Baja Karbon untuk Pipa Hulu dan Hilir sebagai Penyalur Produksi Gas Alam yang Mengandung Gas CO 2. Penelitian yang dilakukan bertujuan untuk mengkaji besaran laju korosi baja karbon yang digunakan sebagai pipa penyalur bagian hulu mapun hilir pada produksi gas alam yang mengandung CO 2. Beberapa parameter yang mewakili kondisi aktual di dalam praktek seperti tekanan parsial CO 2 beserta komposisi larutan, khususnya kadar NaCl ditunjukkan pengaruhnya. Pengujian dilakukan dengan metoda polarisasi dan simulasi dengan menggunakan perangkat lunak PREDICT TM. Hasil penelitian menggambarkan laju korosi baja karbon yang biasa digunakan sebagai pipa penyalur gas alam yaitu jenis API 5L X-52 sebagai pengaruh dari gas CO 2 yang terlarut. Berdasarkan hasil pengujian, diperoleh besaran laju korosi baja di dalam lingkungan yang mengandung CO2 tersebut berkisar antara 15-28 mils per tahun (mpy). Laju korosi baja yang diperoleh ini merupakan nilai yang relatif tinggi sehingga dapat menimbulkan kerusakan yang signifikan terhadap pipa penyalur gas pada bagian hulu maupun hilir. Hasil penelitian merupakan langkah awal terhadap upaya pencegahan terjadinya kebocoran pada pipa penyalur akibat korosi oleh gas CO 2 agar umur pakai yang telah dirancang dapat dicapai.

Eastern-European Journal of Enterprise Technologies, 2020

Однією з галузей, що відіграють важливу роль у підтримці роз витку країни, є нафтогазова промисло... more Однією з галузей, що відіграють важливу роль у підтримці роз витку країни, є нафтогазова промисловість. Крім того, ця галузь впливає на економіку країни, тому вона повинна працювати якомо га ефективніше, щоб не викликати істотних витрат і не відбивати ся на економіці країни. Нафтогазова промисловість оснащена хоро шим допоміжним обладнанням, яке відіграє важливу роль в успіху виробничого процесу. Найважливішим обладнанням для забезпечен ня безперервності виробництва є трубопроводи. Як правило, такі трубопроводи виготовляються з м'якої сталі, а матеріалом, який зазвичай використовується для труб в нафтогазовій промисло вості, є API 5L. Однією з проблем, що виникають в трубопроводах для нафтогазової промисловості є корозія. Це відбувається через агресивні іони, такі як Cl-, а також рідину, що міститься в трубі. Агресивні іони можуть викликати корозію у вигляді точкової коро зії. Корозію, що виникає в трубопроводах для нафтогазової промис ловості, необхідно усувати якомога ефективніше. Одним з рішень, які можуть забезпечити ефективні результати в зниженні швид кості корозії є використання інгібіторів. При додаванні належної концентрації інгібітора швидкість корозії можна знизити на 99 % або більше. Як правило, часто використовувані інгібітори являють собою неорганічні інгібітори, що містять хімічні сполуки, які шкід ливі для навколишнього середовища і здоров'я. Так, в даний час існує багато розроблених екологічно чистих інгібіторів, а саме інгібіто рів, одержуваних з рослин і плодів. Екологічно чисті інгібітори не мають забруднюючого впливу на навколишнє середовище, оскіль ки матеріал цих інгібіторів володіє органічними властивостями. До теперішнього часу було проведено багато досліджень екологіч но чистих інгібіторів на сталі API 5L. Однак дослідження інгібі торів, отриманих з екстракту квіток ареки, в якості екологічно чистих інгібіторів не проводилися. Таким чином, дане дослідження спрямоване на визначення впливу екологічно чистих інгібіторів на коро зійні властивості сталевих труб API 5L в агресивних середови щах, а саме в середовищі HCl. З використанням лінійної поляризації і електрохімічної імпедансної спектроскопії (ЕІС), проведено дослідження екстракту квіток ареки в якості зеленого інгібіто ра корозії на сталі API 5L класу B в 1 М кислотному розчині HCl. Додавання 4 мл, 8 мл, 12 мл, 16 мл і 20 мл інгібіторів корозії при зводить до підвищення ефективності інгібіторів. За результата ми електро хімічної імпедансної спектроскопії (ЕІС), оптимальна ефективність інгібування 96,6 % досягається при додаванні в кон центрації 20 мл. Поліфенольні і флавоноїдні сполуки, що містяться в квітці ареки, інгібують корозію шляхом фізичної адсорбції з утво ренням моношару, який здатний пригнічувати корозію. Адсорбція відбувається мимовільно відповідно до ізотермічної адсорбції Ленгмюра. Як показала поляризація, екстракт квіток ареки діє за допомогою інгібування змішаного типу. Величина вільної енергії адсорбції-7.026 кДж/моль вказує на те, що адсорбція молекул інгі бітору була типовою для фізичної адсорбції Ключові слова: зелені інгібітори, квітка ареки, ЕІС, потенціоди намічна поляризація, втрата ваги UDC 62-1

Materials Science Forum, 2018

Acidizing is one of the stimulation technologies in the oil and gas industry by removing scale, r... more Acidizing is one of the stimulation technologies in the oil and gas industry by removing scale, rust, debris or other acid-soluble particulates on the pipe tubing internal surface. The most common acid used is HCl. To avoid problems such as pipe or casing tubing leak due to acidic corrosion, during the acidizing normally applied with inhibition treatment by inorganic corrosion inhibitor with various compositions including quaternary ammonium salts, solvent and often some surfactant to strip oil from acid reactive surfaces. However, most of these compounds are not only expensive but also toxic to the marine environment. It is an obvious remark to point out the importance of low cost, green corrosion inhibitors which is safe to the environment. The wood extract has become important as an environmentally acceptable, readily available and renewable resource for wide range of inhibitors. A Caesalpinia Sappan L modified imidazoline has been synthesized and used as a corrosion inhibitor for carbon steel in API 5L X60 in HCl 1M environment.The aim of the investigation is to find low dosage-high efficiency green corrosion inhibitor.The testing techniques include wheel test weight loss measurement, Tafel polarization and Electrochemical Impedance Spectroscopy (EIS), Fourier Transform Infra-red Spectroscopy (FTIR). The results of weight loss studies correlated well with those of polarization and Impedance Spectroscopy. Inhibition performance for both Caesalpinia Sappan L modified imidazoline (CS IMI) and Imidazoline (IMI) increases with increasing inhibitor concentration. The formulated Caesalpinia Sappan L modified imidazoline (CS IMI), and Imidazoline (IMI) inhibitors give a greater than 90% inhibition efficiency with dosage 25 ppm at a temperature of 90-140°F. Caesalpinia Sappan L modified imidazoline (CS IMI), and Imidazoline (IMI) show comparable inhibition performance. However, at temperature 140 o F, Imidazoline (IMI) seems to have a slightly better performance, indicating better thermal stability. Caesalpinia sappan bioactive agents are brazilein and chalcone, and its inhibition mechanism by physisorption obey Langmuir Isotherm, this mode will control charge transfer at surface metal and electrolyte.This result confirms that Caesalpinia sappan modified imidazoline is very promising for the development of green corrosion inhibitors for oil and gas application

Acidizing is one of the stimulation technologies in the oil and gas industry by removing scale ,r... more Acidizing is one of the stimulation technologies in the oil and gas industry by removing scale ,rust , debris or other acid-soluble particulates on the pipe tubing internal surface. The most common acid used is HCl. In order to avoid problems such as pipe or casing tubing leak due to acidic corrosion, during the acidizing normally applied with inhibition treatment by inorganic corrosion inhibitor with various compositions including quaternary ammonium salts ,solvent and often some type of a surfactant to strip oil from acid reactive surfaces. But, unfortunately most of these compounds are not only expensive but also toxic to marine environment. It is an obvious remark to point out the importance of low cost, green corrosion inhibitors which is safe to environment. Wood extract has become important as an environmentally acceptable, readily available and renewable resource for wide range of inhibitors. A Caesalpinia Sappan L modified imidazoline has been synthesized and used as a corrosion inhibitor for carbon steel in API 5L X60 in HCl 1M environment.The aim of investigation is to find low dosage-high efficiency green corrosion inhibitor.The testing techniques includes wheel test weight loss measurement,tafel polarization and Electrochemical Impedance Spectroscopy (EIS), Fourier Transform Infra-red Spectroscopy (FTIR). The results of weight loss studies correlated well with those of polarization and impedance Spectroscopy. Inhibition performance for both Caesalpinia Sappan L modified imidazoline (CS IMI) and Imidazoline (IMI) increases with increasing inhibitor concentration. The formulated Caesalpinia Sappan L modified imidazoline (CS IMI) and Imidazoline (IMI) inhibitors give a greater than 90% inhibition efficiency with dosage 25 ppm at temperature of 90-140°F. Caesalpinia Sappan L modified imidazoline (CS IMI) and Imidazoline (IMI) show comparable inhibition performance. But, at temperature 140 o F, Imidazoline (IMI) seems to have a slightly better performance, indicating better thermalstability. Caesalpinia sappan bioactive agent's are brazilein and chalcone and its inhibition mechanism by physosorption obey Langmuir Isotherm,this mode will control charge transfer at surface metal and electrolyte.This result confirm that Caesalpinia sappan modified immidazoline is very promising for the development of green corrosion inhibitors for oil and gas application.

Drafts by Norman Subekti

Chemical Injection is a requirement in the oil and gas production process. Injecting chemicals in... more Chemical Injection is a requirement in the oil and gas production process. Injecting chemicals into the stream is very important, not only in oil & gas (offshore, onshore) but also in other industries. Various chemicals are used, in many critical applications: 1) To remove formation damages 2) Clean blocked perforations 3) Reduce corrosion 4) Improve crude oil quality 5) Flow-assurance in the well/ well bore/ pipeline transportation/ process/ production facilities. The most commonly used chemical injection units employ the energy of gas for dosing, this type called Pneumatic type. Pneumatically powered systems create motive force by utilizing compressed air or gas to power a motor of some sort. The motor applies forces to a plunger or diaphragm system, which in turn injects the chemical at a measured rate. If venting used motive gas is not permitted then solar powered chemical injection system is best option. Oil and gas operation now can depend on solar-powered chemical injection pumping systems for many years of reliable, low-maintenance operation. The solar-powered technology offers quiet, emissions-free operation. Cleaner alternatives to pneumatic pumps, solar systems deliver cost savings by eliminating lost and consumed natural gas. These continuous injection pumps disperse chemicals evenly, have high efficiency motors, are well-suited for remote locations and require no independent, onsite power source.

80 % failure of carbon steel at oil and gas production facility was caused by corrosion. One of c... more 80 % failure of carbon steel at oil and gas production facility was caused by corrosion. One of corrosion mitigation of carbon steel was used green inhibitor. In this study, Caesalpinia Sappan L. extract has been evaluated as green inhibitor corrosion for API 5L X60 in HCl 1M environment with variation of volume extract 0,5 ml, 1ml, 1,5 ml, 2ml, 3ml and variation of temperature 302K, 312K, 322K, and 332K using Tafel polarization and Electrochemical Impedance Spectroscopy (EIS), Fourier Transform Infra-red Spectroscopy (FTIR), dan Stimultaneous Thermal Analysis (STA).The Result show the tafel polarization and EIS show caesalpinia sappan extract acts for inhibit corrosion process in the system with mixed type inhibitor. Optimal inhibiton efficiency occurs at volume 1.5 ml extract caesalpinnia sappan/400 ml HCl 1M, 91% for tafel polarization and 94% for EIS. Current density at volume extract 1,5 ml was 57 µA/cm 2 and resistivity of solution 841 Ω.cm 2. Increasing temperatur of environment will increase current density to 139 µA/cm 2 and decrease resistivity to 121 Ω.cm 2. So, the inhibition efficiency decrease to 50%. Keton fuctional group was found showed exisstance of showed that brazilein dan dan sappanchalcone

Materials Science Forum, 2018

Eastern-European Journal of Enterprise Technologies, 2020

MAKARA of Technology Series, 2012

Eastern-European Journal of Enterprise Technologies, 2020

Materials Science Forum, 2018

Acidizing is one of the stimulation technologies in the oil and gas industry by removing scale ,r... more Acidizing is one of the stimulation technologies in the oil and gas industry by removing scale ,rust , debris or other acid-soluble particulates on the pipe tubing internal surface. The most common acid used is HCl. In order to avoid problems such as pipe or casing tubing leak due to acidic corrosion, during the acidizing normally applied with inhibition treatment by inorganic corrosion inhibitor with various compositions including quaternary ammonium salts ,solvent and often some type of a surfactant to strip oil from acid reactive surfaces. But, unfortunately most of these compounds are not only expensive but also toxic to marine environment. It is an obvious remark to point out the importance of low cost, green corrosion inhibitors which is safe to environment. Wood extract has become important as an environmentally acceptable, readily available and renewable resource for wide range of inhibitors. A Caesalpinia Sappan L modified imidazoline has been synthesized and used as a corrosion inhibitor for carbon steel in API 5L X60 in HCl 1M environment.The aim of investigation is to find low dosage-high efficiency green corrosion inhibitor.The testing techniques includes wheel test weight loss measurement,tafel polarization and Electrochemical Impedance Spectroscopy (EIS), Fourier Transform Infra-red Spectroscopy (FTIR). The results of weight loss studies correlated well with those of polarization and impedance Spectroscopy. Inhibition performance for both Caesalpinia Sappan L modified imidazoline (CS IMI) and Imidazoline (IMI) increases with increasing inhibitor concentration. The formulated Caesalpinia Sappan L modified imidazoline (CS IMI) and Imidazoline (IMI) inhibitors give a greater than 90% inhibition efficiency with dosage 25 ppm at temperature of 90-140°F. Caesalpinia Sappan L modified imidazoline (CS IMI) and Imidazoline (IMI) show comparable inhibition performance. But, at temperature 140 o F, Imidazoline (IMI) seems to have a slightly better performance, indicating better thermalstability. Caesalpinia sappan bioactive agent's are brazilein and chalcone and its inhibition mechanism by physosorption obey Langmuir Isotherm,this mode will control charge transfer at surface metal and electrolyte.This result confirm that Caesalpinia sappan modified immidazoline is very promising for the development of green corrosion inhibitors for oil and gas application.