PERTANYAAN PERSIAPAN PENDADARAN TEKNIK KIMIA (2)

1. Alasan pemilihan tangki horisontal pada dekanter :
a. Karena pemilihan fase terpisah hampir sama, sehingga sama besar kalau dihorisontalkan respon LC nya lebih terlihat
b. Mengatasi tekanan hidrostatika.
c. Meminimasi turbulensi

 
2. Kavitasi : peronggaan yang diakibatkan oleh adanya gas /uap di dalam pompa. Bila pompa sentrifugal beroperasi pada kapasitas yang besar maka tekanan zat cair pada ujung sudu akan menurun. Jika tekanan di bawah P uap zat cairnya (dalam Head) mengakibatkan zat cair tersebut menguap atau membentuk butir-butir air. Sewaktu memasuki sudu, tekanan akan naik sehingga butir tersebut pecah danmenimbulkan suara bising. Proses ini dapat merusak performansi dan pompa itu sendiri.
    Cara mengatasi:
a. menurunkan kapasitas
b. mengawasi kondisi cairan pada suction pumpnya.
    

3. Head pompa : beda tekanan yang dinyatakan dlm tinggi colom cairan

PERTANYAAN PERSIAPAN PENDADARAN TEKNIK KIMIA

1. Bunyi dengung keras pada pipa disebabkan :

a. fluktuasi tekanan

b. kavitasi

c. benturan air

d. keadaan yang tidak seimbang pd bagian yang berputar

2. NPSH adalah tekanan yang dibutuhkan pada suction pompa yang lebih tinggi daripada tekanan uap cairan yang dipompa

3. Untuk menentukan sifat2 pipa dapat ditentukan dari Sch NO, sch ini berbeda-beda dan berguna untuk :

a. menahan internal pressure dari aliran

b. kekuatan dari bhn 

c. mengatasi karat 

d. mengatasi ketegasan pipa

Catatan Program Fasttrack 3: Ide Thesis Takut Dijiplak?!

Tiba-tiba saya ingin menulis tentang topik ini karena beberapa kali hal ini mencuat di benak saya dan teman-teman. Topik ini mlai memanas saat briefing seminar online dan kami diminta memaparkan rancangan thesis kami. Secara spontan, beberapa teman yang kritis mengeluarkan pendapat "bagaimana jika kita menceritakan rancangan thesis kita dan nanti dijiplak oleh orang lain?". Saya sangat dapat memahami pernyataan tersebut. Tujuan dari seminar online adalah untuk saling berbagi ilmu, tapi jika menyangkut ide, apalagi ide yang dibawa adalah baru, fenomenal, atau kreatif yang berpotensi menjadi penemuan baru, tentu kita pasti akan sangat berhati-hati saat share ide tersebut. Apalagi peserta program fasttrack adalah mahasiswa dengan IP S1 yang tinggi (yang saya anggap merupakan calon penemu semua) dari seluruh Indonesia. Akhirnya, dari seminar online yang saya hadiri, semua teman-teman tidak membawa rancangan thesis melainkan hasil tugas akhir mereka.

Masalah tentang "kerahasiaan" ini kembali mencuat setelah beberapa saat lalu saya dan teman-teman menerima e-mail dari UGM yang intinya adalah agar mengirim abstract thesis sebanyak 4 lembar untuk dikirimkan ke Jerman. Tujuannya sangat mulia, yaitu agar pihak Jerman yang membaca ide berlian kami akan tertarik untuk merekrut kami sekolah di Jerman secara gratis (a.k.a dapat beassiwa S3 di Jerman). Sejak awal memang program fasttrack adalah bagian dari debtswap Indonesia dengan pihak Jerman. Tapi sekali lagi, jika ide yang diminta, tentu akan menimbulkan kontroversi, apalagi kali ini kita tidak tahu akan diberikan ke pihak Jerman mana saja ide kita ini. Hmmm... Akankah masalah ini mencuat lagi ke depannya selama program fasttrack? :p

Catatan Program Fasttrack 2: Administrasi... administrasi...

Menyambung cerita dari Catatan Program Fasttrack 1, di mana di sela-sela presentasi online kembali ditegaskannya kewajiban mahasiswa peserta program fasttrack untuk melakukan ISR (Intellectual Social Reaponsibility) dalam bentuk mengajar baik di SMA/SMK atau menjadi asisten dosen. Saya kagum dengan komitmen Pak Agus, Pak Nur, dan Pak Jaslin. Selama ini saya sebenarnya ingin melakukan ISR (tentunya jika sudah menerima hak kita=beasiswa S2, sangatlah tidak pantas klo tidak melakukan kewajiban kita, salah satunya melakukan ISR), tapi seperti yang teman-teman fasttrack lainnya, saya tidak tahu prosedur agar dapat mengajar di SMA.

Semuanya bermula dan berakhir di "administrasi". Awal permasalahan "administrasi": untuk mengajar di SMA tentu butuh ijin=surat ijin, tapi kita tidak tahu untuk mendapat surat ijin ini saya harus ke mana/menghubungi siapa (UGM? Seamolec? Dikti? Diknas?). Saya senang karena respons beliau bertiga sangatlah cepat terhadap hal ini. Hanya beberapa hari setelah seminar online pertama, mahasiswa fasttrack UGM mendapat e-mail tentang cara mengajukan surat ijin ISR. Prosedurnya pun sangat mudah, dalam beberapa menit saya dan teman-teman dapat memperoleh surat ijin ISR dari UGM beserta copy surat kewajiban melakukan ISR dari Kemendiknas dan daftar peserta program fastrack sebagai lampirannya.

Selasa, tanggal 3 April saya dan teman saya (Yano dan Galuh) mengajukan surat tersebut ke salah satu SMA negeri di Kota Yogyakarta. Dua hari kemudian, kami datang lagi ke SMA tersebut untuk menanyakan respons dari pihak sekolah. Ternyata respons dari pihak sekolah tidak terlalu positif. pada intinya sekolah mempertanyakan kelengkapan surat kami. Pihak sekolah berkata bahwa di antara surat tersebut tidak ada surat yang menyatakan bahwa Diknas (tingkat Kota atau Provinsi) memberikan "ijin" bahwa sekolah mereka akan "dimasuki" mahasiswa fasttrack dan dijadikan lokasi ISR. Menurut saya pribadi, adanya surat edaran dari Kemendiknas tentang kewajiban kami mengajar di SMA sudah mewakili hal tersebut, tapi rupanya pihak sekolah merasa itu tidak cukup. Pihak sekolah merasa tidak adanya surat secara spesifik dri Diknas kepada sekolah tersebut tidak cukup kuat untuk dijadikan dasar bahwa kami bisa mengajar di sana, karena pihak sekolah tidak ingin mendapatkan masalah jika ada keluhan dari orang tua siswa jika tiba-tiba ada tambahan pelajaran dari mahasiswa/mahasiswa mengajar di kelas formal tanpa disertai surat tadi. Pihak sekolah baru berani menerima kami mengajar di sana jika ada lampiran surat tugas dari pihak Diknas Provinsi/Kota. --- berakhir di masalah "administrasi" (lagi).

Hmmm... Saya dan teman-teman segera ingin menyelesaikan masalah itu hari itu juga. Setelah bolak-balik berbagai gedung UGM mencari pihak yang berwenang tapi akhirnya nasib tidak mengijinkan, akhirnya saya mengirim e-mail ke pihak UGM mengenai masalah ini. Melalui e-mail, UGM akan berusaha membantu menyelesaikan masalah ini. Semoga usaha ini akan segera membuahkan hasil. (apakah UGM bisa meminta Diknas mengeluarkan surat itu atau tidak), dan semoga tidak malah menggantung di sini saja nasib ISR kami.

Saat ini memasuki pertengahan bulan April, dan tahun ajaran berakhir di pertengahan bulan Juni. Tentunya jika kami ingin mengajar di SMA hanyalah mungkin sebelum ujian kenaikan kelas (sebelum bulan Juni). Opsi untuk mengajar sebagai asisten dosen juga tertutup karena di jurusan saya, mahasiswa hanya bisa menjadi grader/asisten lab, dan asisten dosen adalah dosen muda. Semoga yang terbaik yang terjadi... dan saya harap hal itu adalah keluarnya surat dari Diknas sesegera mungkin.

Why Natural Gas Is Cheap and Gasoline Isn't

THE price of gas has risen rapidly this year

The price of gas has fallen to the lowest level in a decade. 

Both of those statements are true. The first refers to gasoline, the second to natural gas. 

As the accompanying charts indicate, never in the two decades that natural gas and oil futures have traded have their prices diverged as much as they have now. On an energy equivalent basis, oil costs more than eight times as much as natural gas.

This week, the price of a million B.T.U.’s of natural gas fell below $2.20 for the first time since 2002, while oil prices slipped a little but remained above $100 a barrel. The last time natural gas was this inexpensive, oil cost about $20 a barrel.

The diverging prices reflect the fact that while oil and natural gas can substitute for each other in some uses, the markets for the two products are very different.

Crude oil is a relatively efficient international market, in which the product moves around the globe in tankers that can be diverted from one destination to another almost instantaneously in response to shifts in demand. A sharp change in demand or supply in any region of the globe is likely to show up in prices everywhere.

Oil prices can also be affected by geopolitical concerns well before actual events take place. These days, it appears that oil prices have been pushed up by worries that Israel might attack Iran, leading to a drastic reduction in Iranian oil exports.

The natural gas market, on the other hand, is not a global one. There is a limited trade in liquefied natural gas, which can be transported in tankers, but mostly natural gas must move in pipelines over land. Natural gas prices have been rising in Britain this year even as they have been falling in the United States.

Supply has soared in the United States because of increased production from hydraulic fracturing, but demand cannot change rapidly. Power plants that can burn natural gas or oil were shifted to gas long ago. Add in a relatively mild winter in the United States, which reduced demand, and there appears to have been a glut.

There are efforts being made to use more natural gas. Some fleet vehicles, like buses, already use natural gas, but that market is limited to vehicles that can return to their headquarters for refilling. Chrysler has announced a pickup truck that will run on both gasoline and natural gas, but plans to offer it only to such fleets.

The state of Alaska is also seeking a pipeline that would take natural gas from the North Slope to an Alaskan port, where it could be liquefied and shipped to Asia. The state announced an agreement with Exxon Mobil, BP and ConocoPhillips relating to that project on Friday, but many details remain to be worked out.

Two of the charts show trends in prices of gasoline and natural gas since the end of 2007, when the United States entered recession. At first, reduced economic activity led to reductions in the prices of both products. But the trends began to diverge in 2009. Now, gasoline costs about 30 percent more than it did in 2007, while natural gas costs around 70 percent less.

For what it is worth, which may not be very much, futures traders think that the gap in prices will diminish but remain large. A year from now, oil prices are expected to be almost exactly where they are now, while natural gas prices are forecast to have risen more than 50 percent. If that happens, on an energy equivalent basis, crude oil will still be more than five times as expensive as natural gas.

Source:
Floyd Norris comments on finance and the economy at nytimes.com/economix.

Catatan Program Fasttrack 1: Seminar Online Pertama

Hari ini untuk pertama kalinya mahasiswa fasttrack dari seluruh Indonesia (UGM, UI, ITB, Undip) melakukan seminar online. Walaupun agak sebal di awal, karena pemberitahuan tentang teknis pelaksanaan seminar online hari ini baru diberikan kemarin siang jam 1 siang, hal ini tetap harus dijalani sebagai bagian dari rangkaian program fasttrack. Secara pribadi, saya mendukung penuh rangkaian program ini, baik konsep pemberian beasiswa kuliah s2 sejak mahasiswa menjalani semester 7 di program s1 nya, kewajiban melakukan ISR (Intellectual Social Responsibility) berupa mengajar di SMA/SMK, membuat blog, sampai kewajiban melakukan seminar (seperti seminar online hari ini). Mungkin beberapa teman ada yang masih mengeluh, tapi saya tahu benar kalau semua ini dibuat demi kebaikan kita sendiri.

Seminar online hari ini dimulai pk 8.30 pagi. Jujur saja, konsep seminar online yang pertama ini kurang jelas. Tidak adanya daftar pemateri sampai acara yang tidak sesuai dengan jadwal masih terjadi. Saya tidak mengikuti seminar online dari pagi hari baik melalui website www.seamolec.org/ft maupun menonton langsung di lantai 2 Gedung MST UGM. Alasan saya cuma karena saya ada kuliah dan kegiatan lain yang lebih dulu sudah saya sanggupi. Sekitar jam 11 siang saya melihat lewat website seamolec, dan masih ada beberapa kendala teknis untuk streaming langsung. Walaupun demikian, saya salut dengan ide seminar online ini. Saya lebih setuju bahwa mahasiswa dibebaskan untuk menonton seminar dari manapun karena toh tidak semua topik yang diseminarkan akan menarik perhatian semua orang.

Saya datang ke gedung MST pk 12.30 untuk persiapan seminar online pk 13.55. tetapi ternyata pk 13.00 tiba-tiba seminar online di UGM ditunda untuk sementara waktu karena ada penjelasan dari Pak Jaslin dan Pak Agus tentang program fasttrack. Thank's God! Baru saja semalam saya email pihak seamolec mengenai kejelasan program ini. Saya kurang tahu di mana hambatannya sehingga UGM terkesan selalu tertinggal dalam berbagai informasi mengenai program fasttrack (seperti tentang teknis seminar online hari ini, teknis mengajar di SMA, banyaknya biaya s2 yang diperoleh, dll). Pertemua siang ini cukup memberi kejelasan dan kepastian mengenai ISR. Setelah dijelaskan dan dipastikan bentuk ISR dan prosedur monitornya tentu pihak mahasiswa akan lebih mudah untuk melaksanakannya (dan pihak penyelenggara dapat menetapkan punishment jika aturan yang telah jelas dilanggar). Memang akhirnya saya tidak jadi seminar online karena tidak cukupnya waktu. Hmmm,,, mungkin kesempatan berikutnya baru kesempatan bagi saya. Pada saat tulisan ini dibuat saya masih berusaha mengakses situs seamolec untuk melihat-lihat hasil seminar online dari Universitas lain, tapi websitenya tidak bisa terbuka juga. *semoga tidak terjadi masalah yang serius di web ini. Haha.

Brief Overview of Heat Exchanger

n the chemical processing industry, there are numerous types of heat exchanger devices. The types of exchangers can be classified by the duty that they perform, surface compactness, construction features, flow arrangements, and others. In general, a heat exchanger can fall into one of these processing categories:

1. No Phase Change

• Liquid to Liquid heat transfer
• Liquid to Gas heat transfer
• Gas to Gas heat transfer

Heat Exchanger Equation

If we take a closer look at the heat exchanger equation, it's worth noting some assumptions that are made in its derivation. First, the overall heat transfer coefficient and the specific heat (also called heat capacity) of the fluids are assumed to remain constant through the heat exchanger.
If we look at the change in the heat capacity of water, for example, over a reasonable temperature range, here is what we find:

Specific heat of water at 100 °F and atmospheric pressure = 0.9979 Btu / lb °F
Specific heat of water at 210 °F and atmospheric pressure = 1.0066 Btu / lb °F

So, we can see that this is a fairly reasonable assumption for water and it remains reasonable for most industrial fluids. The specific heat of a substance is defined as the amount of heat required to raise the temperature of one pound of the substance by a single degree Fahrenheit (other units can apply as well).

Basics of Industrial Heat Transfer

Heat transfer is one of the most important industrial processes. Throughout any industrial facility, heat must be added, removed, or moved from one process stream to another. Understanding the basics of the heart of this operation is key to any engineers' mastery of the subject.

There are three basic types of heat transfer: conduction, convection, and radiation. The two most common forms encountered in the chemical processing industry are conduction and convection. This course will focus on these key types of heat transfer.

In theory, the heat given up by the hot fluid is never exactly equal to the heat gained by the cold fluid due to environmental heat losses. In practice, however, they are generally assumed to be equal to simplify the calculations involved. Any environmental losses are generally minimized with insulation of equipment and piping.

Any overall energy balance starts with the following equations:

Interesting Facts About Wood Furnaces

Wood furnaces are direct fire heaters. It is a convenient and economical way of heating homes. Many Americans, Europeans, Canadians and people from other countries who experience very cold weather or climate use this kind of unit.
Many users nowadays prefer using wood furnaces to save the Earth from greenhouse effect. Burning bio-mass fuels does not increase the risk of carbon dioxide in the atmosphere. Since wood is a renewable resource safe for the environment, it can also conserve energy.
There are three main types of wood furnaces. First is the Central Wood Furnaces. It can be installed inside the house, garage, mechanical room or at the basement. It uses either a type of forced-air or hot-water system to distribute heat throughout the house.
The second type is the Multi-Fuel Furnaces. This unit can be placed inside or outside the house. It enables the burning of different kinds of fuel like coal, oil, gas and wood. These types are flexible that can work as a back-up option, especially when using other kinds of fuel. It is appropriate in cases where there is only one chimney outlet available. The machine allows venting of the wood as well as the fossil fuel so as to exhaust-up the same pipe.
The third type is the Outdoor Furnace or Boilers. This unit utilizes firewood, particularly when there is a huge supply. It keeps the smoke, mess and bugs outside. The furnace is similar to a small utility building. It is a wood burning furnace placed outdoors. It can be found along the yard, between 50 and 150 feet away from the house.
The furnace firebox is surrounded by a water jacket. As heat is released, it is transferred from the fire onto the water. It is then pumped through insulated pipes and placed underground, then into your house. Finally, heat radiates to warm up the entire house.
On the downside, this unit needs some boots, gloves and a cap to slog out onto the blowing snow to keep it going. Many outdoor boilers are hard to control for a clean burn due to their oversized firebox. Aside from this, it tends to smoke a lot during automatic restart after a long off cycle.
All these wood furnaces are controlled by a thermostat similar to other heating systems. Different heating systems are used on working on these types.
The forced hot-air systems use heat exchangers. The warm air spreads out with ductwork. Burning fuel causes the heat exchanger to heat-up. However, there is no heat storage capacity in this system. The unit needs to be re-fueled everyday to maintain its temperature during the cold months. It is also easy to add filtration, air-conditioning and humidification because the air in this system is being re-circulated. Hydro-air units use ductworks to help distribute air similar to forced hot-air systems. The heat exchanger is replaced by a hot water coil being heated by a hot water loop from its boiler. There are multiple hydro-air units that can be fed by a single boiler throughout the sections of the house for different cool zones. This kind of system is always combined with air-conditioning.
A combination central-heating unit system is designed to burn wood, oil or gas. It relies on the back-up fuel when the wood is not convenient for usage. Both combustion chambers can be maximized with this design. The two fuels are not usually used simultaneously. It can either be hot-air or hot-water furnaces. The disadvantage of this unit is that it tends to be twice as expensive as a single-fuel heater. This dual system offer maximum fueling flexibility.
Wood furnaces have disadvantages also. Some needs to be refueled several times and are a bit dirty to operate. It is also not always convenient to gather fire woods. And to produce good heat, you must know how to stack these pieces of wood properly. Lastly, all these units require electricity due to its thermostat.

Source:
heatexchanger.blogspot.com

Chemical Engineer Salary

Salary Overview

There are a number of different statistics and estimates for the projected annual salary of someone employed as a chemical engineer in the United States. According to statistics provided by the Bureau of Labor, there are approximately 29,000 chemical engineers working in the country, and the mean annual wage is $91,670. The middle 50 percent of people employed as chemical engineers obtain an annual wage of $88,280 with an hourly wage of $42.44. The lowest 10 percent obtain an annual wage of $56,090 with an hourly wage of $26.97, while the highest 10 percent obtain an annual wage of $132,980 with an hourly wage of $63.93. The industries with the highest employment rates in chemical engineering are architectural engineering, basic chemical manufacturing, and scientific research and development areas. The highest paying industries for chemical engineering involve oil and gas extraction, management, technical, and scientific consulting, and motor vehicle part manufacturing.

Job Description and Outlook

The job of a chemical engineer is to use different principles, concepts, and theories related to chemistry and engineering to solve novel problems that involve how chemicals may be produced or used or combined with other products. Chemical engineers may be involved in a number of processes in chemical manufacturing, such as designing equipment and procedures, or planning and testing methods involved in products and byproducts. They are also likely to be involved in supervising the production of items manufactured through the manipulations of chemicals and plastics. Chemical engineers may also work in a number of industries related to manufacturing besides chemical manufacturing, such as industries involved in the production of electronics, energy (in particular, oil and gas), food, paper, and clothing. Chemical engineers can also find employment in health care, education, and bio technology.

The outlook for chemical engineering as a profession in the United States is healthy; the profession is projected to grow on a rate comparable to the average growth rate of most professions; however, the specific growth rate will vary by the specialty of chemical engineering an individual works in. Chemical engineers involved in the chemical manufacturing industry may actually face a slight decline in employment opportunities over the coming decade, although there will continue to be a number of chemical companies that employ chemical engineers for research and development purposes. Chemical engineers will continue to be in demand in applications and industries involving energy, particularly the industries involved with extraction and refinement of oil and natural gas from the world’s oceans. There will also be a need for engineers versed in safety practices to reduce the likelihood of disasters occurring from industrial incidents, such as oil spills and chemical fires and explosions. There is also expected to be employment growth for chemical engineers who participate in industries related to the provision of services, such as technical services, scientific services, and professional services. The fields of nano technology and bio technology are in rapid development, and chemical engineers will likely be able to seek employment in these fields due to their credentials in engineering and expertise in the manipulation of chemicals and related products.

Training and Education Requirements

The typical terminal requirement in most areas of employment for a potential chemical engineer is a doctoral degree. There are some areas and fields where it may be possible to find employment without a terminal degree, such as in the Federal Government, but the default expectation is for candidates to have completed their education with a Ph.D., and in certain sub industries, having real life work experience is also desirable.

It is possible in many cases to work with a bachelor’s degree in supportive roles as a chemical engineer, depending on the setting and the needs of the employer. In fact, chemical engineers earn among the highest starting salaries of any workers with bachelor’s degrees, and chemical engineers who obtain experience in petroleum engineering may be able to negotiate higher salaries and more opportunities without much trouble. Many employers will pay their employees to further their education.

Certifications

It is usually not necessary to obtain certification to begin working as a chemical engineer. However, there can be benefits to seeking voluntary certification from different professional organizations, such as higher salaries within current locations of employment and access to more lucrative employment opportunities. There are a number of professional associations and organizations from which certification as a chemical engineer may be obtained. The specific requirements for obtaining certification as a chemical engineer will vary from one association to the next. Many organizations request a particular amount of formalized education and post doctorate work, while others are more interested in years of work experience. Still others may ask for a combination of work experience and degrees accumulated through formal education and schooling.

Professional Associations

There are a number of organizations and associations in the chemical engineering industry that offer certification to chemical engineers.

• The American Chemical Society
• The American Institute of Chemical Engineers
• The Electrochemical Society
• The National Organization for the Professional Advancement of Black Chemists and Chemical Engineers
• The American Hydrogen Association
• The Association of Energy Engineers

Source:
www.highersalary.com

How Long Will Our Earth Provide Us With The Oil We Need??

The Oil and Gas Industry is doing well. As everyone knows, the price for oil has gone up significantly over the last years. Within every kind of market, the price is set and set by the supply and demand balance. At the moment countries such as India and China are booming markets. Their economies are growing with big numbers every year. As their economy continues to grow, so does the demand for gas and oil. This also means that the production facilities must expand. The current consumption of oil in the world is nearly equivalent to the total amount of production facilities- and for this reason relatively small events in the world can have a big impact on the oil price at the moment. Wars and other major events such as hurricane Katrina have an even bigger impact on the price since they created great concerns and worries for the buyers, which pushed the price further up.

In the near future the fragile balance between supply and demand will not fade so quickly. The demand for oil is still increasing in western countries, but also in the fast growing countries such as India and China.

Although prices are high at the moment, when seen on the historic scale this does not mean that the price is indeed high when compared to the current market situation and future of oil reserve. Some say oil should be double or quadruple of the current price to fill the gap between oil and renewable energy sources, but higher prices will automatically make alternative energy resources more economical.

Currently it is expected that the world's demand for oil will increase about 2% per year in the first 25 years of the 21st century, according to the Energy Information Agency of the U.S. government. This makes it very clear that oil and gas companies will have to increase their production facilities to pump more oil and refine it into the products needed to keep the world economy going and growing. 

Source:

http://www.hirednotfired.com

A Survival Guide to Chemical Engineering (by Dr. Lisa G. Bullard , Department of Chemical and Biomolecular Engineering North Carolina State University)

1. Develop a strong work ethic.

This theme was echoed in almost every student response. There is no such thing as a lazy (successful) chemical engineer. You do not have to be brilliant to be a chemical engineer, but you do have to have the dedication, persistence, and downright stubbornness to keep working at it until you get it. Along the way you will doubt yourself. Those who really want it will succeed.

Most importantly, in order to understand a chemical engineering subject requires time, lots of time. Time spent reading the text, reviewing notes, speaking to the professor, working on the problem sets solely, working on the problem sets collectively, speaking to the TA, and going to problem session. One is also required to quickly develop a work ethic that has never been required before, because in high school they never studied and did well and freshmen year was hard but they still managed to do well with simply doing the homework and studying right before the test. This approach will not prove successful in chemical engineering. 

2. Get used to working in groups. 

I recommend that everybody taking these classes should have a group of people that they can study with. Everyone approaches complex  problems differently so working with a team may allow someone to see an aspect of the problem that they would otherwise not consider.

At the beginning of your study, you may think you have it all under control. Don’t learn the hard way that a study group is a great source for understanding CHE material. In addition, you may be the resource someone else needs to understand a topic. Working in groups has mutual benefits. Remember, the group members need and value your input as much as you need and value theirs. I did everything short of going to the bathroom with my group.

 3. …but don’t rely on group work to carry you through. 

My instructors always emphasized working in groups, but being able to do the problems independently. Unfortunately, I didn't fully appreciate that advice until later on. The problems never look that difficult when you see the solutions your group members or instructors develop. The solutions are usually straightforward and relatively short.

However, the amount of trial and error and flipping through notes and books that it takes to develop those answers seems endless if you actually complete all the problems on your own. So when you sit down and take your first exam, you need to be able come up with these "short" answers on your own from all the information you have been taught up until that point. This can be difficult or impossible if you have relied on your group to carry you along.

Perbandingan Gaji di Perusahaan Minyak dan Gas

1. Chevron

Chevron adalah salah satu perusahaan energi terbesar di dunia. Pusatnya ada di San Ramon, California. Selain migas, Chevron juga bermain di eksplorasi, produksi, refinery, pemasaran dan transportasi, pembangkit energi, sampai chemical product.

Perusahaan ini berdiri tahun 1879 di Pico Canyon, California. Pada 2001, Chevron merger dengan Texaco dan membentuk ChevronTexaco. Namun pada 9 Mei 2005, ChevronTexaco melepas moniker Texaco dan kembali ke nama Chevron. Texaco tetap menjadi merek di bawah Chevron. Pada 19 Agustus 2005, Chevron bergabung dengan Unocal Corporation, sebuah gerakan yang membuat Chevron produsen terbesar energi geotermal di dunia.

Chevron terbilang cukup loyal terhadap karyawannya. Tabel di atas adalah berdasar PKB tahun 2006. Konon komponen tersebut sudah mencakup basic salary plus 21% regional allowance. Fresh graduate umumnya masuk di tingkat 18A.

Kiat Membuat Proposal Magang dan KP

Magang dan KP bagi beberapa orang memang mampu menjadi jalan 'pintas' untuk mendapatkan pekerjaan impian. Kegiatan ini tak hanya memberikan kesiapan mental saat melamar pekerjaan namun juga memberi gambaran riil dunia kerja.

Nurhadi, Direktur ECC UGM, mengatakan melamar magang atau KP ke perusahaan sama seperti halnya melamar sebuah pekerjaan. Anda juga butuh menampilkan potensi diri sehingga perusahaan layak menerima Anda untuk magang di perusahaannya. Potensi ini mula-mulanya dilihat perusahaan melalui proposal yang Anda kirimkan. Lalu, bagaimana cara membuat proposal magang dan KP yang baik? Simak tip-tip berikut.

Pertama. Sampaikan tujuan Anda dengan jelas sehingga perusahaan tahu apakah mereka bisa memenuhi keinginan Anda. Karena tidak selalu kebutuhan perusahaan sejalan dengan kebutuhan Anda. Siapa tahu load bidang pekerjaan yang Anda lamar sedang tidak membutuhkan tenaga tambahan. Tuangkan tujuan tersebut dalam bentuk kegiatan.

Kedua. Menjelaskan rencana kegiatan dengan detail. Cantumkan berapa lama kegiatan tersebut bisa Anda lakukan. Benefit apa yang perusahaan bisa terima dari kegiatan Anda tersebut. Dan jika perlu, gunakan konsep 5W+1H (What, When, Who, Why, Where, and How). "Akan lebih baik lagi jika kegiatan tersebut jelas-jelas bisa mengatasi masalah perusahaan," ujar Sri Muliati Abdullah, Staf Ahli Bagian SDM dan HR Service ECC UGM. Satu poin yang perlu diperhatikan dalam penyusunan kegiatan adalah mempertimbangkan kemampuan, periode, dan beban kerja Anda.

Ketiga. Pilih lokasi dan pekerjaan magang sesuai minat Anda. Meski sifatnya wajib dan berbeda dengan magang, Anda tetap boleh memilih di perusahaan dan jenis pekerjaan seperti apa yang akan Anda lakukan saat KP. Tapi tentu saja sesuai dengan background studi Anda. Misalnya, jika Anda mengambil jurusan Teknik Kimia, Anda bisa memilih bidang kegiatan tentang pangan, energi, ataupun lingkungan. Apapun, sesuai dengan minat Anda. "Kalau berminat, maka dia juga akan termotivasi menjalaninya," ujar Waziz Wildan, Ketua Jurusan Teknik Mesin dan Industri UGM.

Keempat. Tentu saja, proposal magang atau KP akan diperhatikan perusahaan ketika ada yang memayungi kegiatan tersebut. Pastikan proposal Anda mendapat pengesahan dari fakultas. Sertakan surat ijin permohonan magang dari instansi tersebut. "Kalau ada apa-apa, perusahaan akan mudah menelusur datanya," terang Sri Muliati Abdullah.

Nah, lalu berkas apa saja yang sebaiknya Anda lampirkan bersama proposal permohonan magang?

Seperti apa yang disebutkan di atas, selain proposal Anda juga harus menyertakan surat ijin magang dari fakultas yang bersangkutan. "Di jurusan kami juga ada Surat Perintah Kerja Praktik sebagai legalitas si anak dalam menjalankan KP," terang Waziz Wildan. Selain itu, Anda bisa juga menyertakan transkrip nilai sementara.Nurhadi menambahkan untuk menyertakan biodata beserta pengalaman organisasi Anda. tuliskan pengalaman ini secara mendetail beserta deskripsi kerjanya. "Jadi meski tidak melalui proses wawancara, perusahaan tahu Anda bisa," ujarnya. Proposal magang dapat dikirim melalui dua cara, yakni via pos maupun via email. 

Untuk membuat proposal Anda diperhatikan, ada baiknya menuliskan 'perihal surat' di amplop luar jika Anda mengirimnya via pos. Jika Anda mengirim via email, tuliskan subject yang membuat si pembaca langsung tahu bahwa email tersebut berisi permohonan magang. Misalnya, "Permohonan magang/KP".

Selamat mencoba.. ^^

Source:

ecc.ft.ugm.ac.id

Magang : Jalan 'Pintas' Mendapatkan Pekerjaan Impian

Apa Anda mahasiswa tingkat akhir yang sedang berencana magang atau kerja praktek (KP)? Jika iya, baca dulu artikel ini.

Banyak istilah untuk menggambarkan kegiatan mencari pengalaman di perusahaan bagi mahasiswa. Ada yang menyebutnya magang, KP, ataupun PKL. Namun sebenarnya, beda istilah beda pula hasilnya.Ir. M. Waziz Wildan, Msc. PhD., Ketua Jurusan Teknik Mesin dan Industri UGM, mengatakan magang sama dengan bekerja untuk perusahaan. Sehari-hari dia melakukan pekerjaan selayaknya karyawan perusahaan.

 

Magang tidaklah wajib di beberapa jurusan perguruan tinggi. Magang bisa juga dilakukan karena inisiatif sendiri. "Biasanya ada mata kuliah tertentu, dan dia butuh magang untuk bisa mendalaminya, semua tergantung kebijakan jurusan masing-masing,"ujar Nurhadi, Direktur ECC UGM. Ada juga mahasiswa yang melakukan magang dengan tujuan untuk bekerja di perusahaan tersebut. Tak mengherankan jika kemudian hasil akhir yang diharapkan adalah diterimanya mahasiswa tersebut untuk bekerja di perusahaan tempatnya magang. "Tidak untuk memenuhi SKS, sehingga tidak mendapat nilai," tambah Waziz Wildan.

 

Sedangkan KP biasanya dilakukan untuk memenuhi kebutuhan SKS. KP juga menjadi syarat kelulusan. Benar saja, Waziz Wildan mengatakan jurusannya menerapkan 2 SKS untuk kegiatan ini. Kegiatan saat KP biasanya harus sesuai dengan kegiatan yang ada dalam proposal serta kebutuhan perusahaan. Memang berbeda, namun keduanya memiliki manfaat yang hampir sama.

 

Pertama, Anda bisa mempraktekkan teori yang sudah Anda dapat di bangku kuliah. "Memberikan wawasan riil tentang industri ke mahasiswa," ujar Waziz Wildan. Dengan magang atau KP, Anda tidak hanya menguasai teorinya, tapi juga belajar bagaimana prakteknya.

 

Kedua. Anda akan merasa lebih percaya diri ketika sudah saatnya mencari kerja. "Karena secara skill dia sudah siap, sehingga dia merasa lebih percaya diri," ujar Nurhadi.

 

Ketiga. Selain skill, Anda juga mendapat pengalaman mengenal bagaimana budaya kerja di perusahaan. Tentu berbeda antara dunia kuliah dan dunia kerja. Dengan magang atau KP, Anda memiliki banyak kesempatan mengetahui bagaimana budaya di dunia kerja.

 

Keempat, luasnya jaringan karir. Jika Anda mampu menampilkan performa kerja yang optimal, siapa tahu perusahaan melirik Anda untuk bekerja di perusahaan tersebut ketika lulus nanti.

 

Nah, karena banyak manfaatnya, magang atau KP harus dijalani dengan serius. Beberapa perusahaan, seperti Schlumberger dan Nestle, menerima magang karena ingin mendayagunakan mahasiswa magangnya. Oleh karenanya, mereka tidak sembarangan dalam memilih karyawan magang. "Disesuaikan dengan kebutuhan perusahaan dan core bisnisnya," ujar Nurhadi. Karena magang juga berpotensi bagi seseorang diterima menjadi pegawai. Anda juga jangan sembarang pilih. "Pilih yang sesuai ketertarikan, apa yang ingin dikejar, dan gali ilmu sebanyak-banyaknya," tutur Nurhadi. Pilih perusahaan dan bidang pekerjaan yang memang menjadi ketertarikan Anda. "Kalau berminat, maka dia juga akan termotivasi menjalaninya," ujar Waziz Wildan.

 

Kapankah waktu yang tepat untuk magang dan KP?

Sri Muliati Abdullah, Staf Ahli Bagian SDM dan HR Service ECC UGM, mengatakan KP idealnya dilakukan saat teori sudah hampir habis. "Biasanya semester 7," ujarnya. Mengapa? Selain karena teori-teori sudah habis dipelajari, menurut Nurhadi mahasiswa di semester 7 biasanya sudah mengetahui minatnya di mana. Sehingga mahasiswa menjalani KP pun bukan karena sekadar memenuhi SKS. Lebih dari itu, mereka bisa mengejar apa yang menjadi ketertarikan mereka.

 

Berbeda lagi dengan magang. Mungkin waktu pelaksanaan magang bisa lebih fleksibel dibanding KP. "Kan ada juga magang yang dilakukan untuk memenuhi mata kuliah tertentu," ujar Sri Muliati Abdullah. "Biasanya kalau sudah dekat-dekat tugas akhir, sekalian melakukan riset," terang Waziz Wildan.Nah, ada beberapa poin penting yang sebaiknya mahasiswa lakukan saat magang atau KP, yakni:

 

Satu. Sebagai siswa magang atau KP, Anda sebaiknya mempelajari aturan dan budaya perusahaan. Menjalani magang atau KP sama halnya dengan bekerja. Anda juga butuh beradaptasi agar apa yang menjadi tujuan bisa diraih. Tentu Anda tidak mau, dicap buruk oleh perusahaan usai magang atau KP.

 

Dua. Menjalankan kegiatan yang sudah dituliskan di proposal. Tunjukkan Anda memang memiliki potensi untuk melakukannya. Jangan justru tidak serius dan seenaknya.

 

Tiga. Menggali sebanyak-banyaknya ilmu, khususnya dari atasan Anda. "Kan ada banyak laboratorium, manfaatkan saja," tambah  Nurhadi. Apalagi jika magang yang Anda lakukan ditujukan untuk menunjang riset tugas akhir Anda.

 

Terakhir. Tentu saja, lakukan konsultasi teratur dengan dosen pembimbing. Mintalah saran ketika Anda menemui kesulitan di lokasi magang atau KP.

 

Source:

ecc.ft.ugm.ac.id

Top Colleges Offering Petroleum Engineering Courses in USA

S.No.	University Name	State	Rank	Tution Fee / App. Fees	Accept. Rate	Deadline/Fall / Spring	Avg GRE / TOEFL
1	University of Texas Austin (Cockrell)	TX	1	$11,748 / $75.00	22.50%	1-Jan / 1-Oct	1300 / 213
2	Stanford University	CA	2	$37,110 / $105.00	28.00%	See Comment	1360 / 230
3	Texas A&M University College Station (Look)	TX	3	$8,712 / $75.00	37.20%	1-Mar / 1-Oct	1269 / 213
4	University of Tulsa	OK	4	$778 (per credit hour) /$40.00	47.90%	15-Jan	1159 / 213
5	Colorado School of Mines	CO	5	$21,744 / $70.00	70.30%	1-Apr / 1-Sep	1204 / 213
6	Pennsylvania State University University Park	PA	6	$26,050 / $45.00	31.90%		1221 / 213
7	University of Oklahoma	OK	7	$12,432 / $90.00	69.90%	1-Apr / 1-Sep	1194 / 213
8	Louisiana State University Baton Rouge	LA	8	$11,281 / $25.00	38.70%		1189 / 213
9	University of Southern California (Viterbi)	CA	9	$22,734 / $85.00	46.60%	15-Jun / 1-Oct	1236 / N/A
10	New Mexico Institute of Mining and Technology	NM	10	$11,901 / $16.00	47.80%	15-Feb / 15-Sep	N/A / 207
11	Texas Tech University	TX	11	$472 (per credit hour) / $60.00	38.90%	1-Mar / 1-Sep	1171 / 213
12	University of Kansas	KS	12	$575 (per credit hour) / $55.00	61.10%	10-Jan	N/A / 200
13	West Virginia University	WV	13	$15,664 / $50.00	46.20%		1149 / 213

Source:
http://www.accesseducationindia.com

Top Petroleum Engineering Universities

Following are some of the top leading universities for petroleum engineering:

Heriot-Watt University (UK)
- The postgraduate Institute of Petroleum Engineering (IPE) is world renowned for its research on optimising economic hydrocarbon recovery. It has received 5* research ratings in the 1996 and 2001 Research Assessment Exercises.
- In 1995 Heriot-Watt received one of the inaugural Queens Anniversary Prizes for Higher and Further Education in recognition of the outstanding achievements of the Institute of Petroleum Engineering.
- In 2006 the Energy Institute granted accreditation to the MSc Petroleum Engineering and MSc Reservoir Evaluation & Management courses.
- The Petroleum Engineering department is consistently rated one of the top three in the world.

Texas A&M University (USA)
- The Harold Vance department of petroleum engineering at Texas A&M University is one of the top petroleum engineering programs in the United States. According to US News and World Report, the department has been rated the 1st among undergraduate petroleum engineering program in the United States.

University of New South Wales (Australia)
- The School of Petroleum Engineering (SCOPE) was established in 1985 as a joint initiative between UNSW and the petroleum industry.
- SCOPE is Australia's longest standing undergraduate and postgraduate petroleum industry training school.

The University of Adelaide (Australia)
- The Australian School of Petroleum (ASP) was created at the University of Adelaide in July 2003 by the merger of the National Centre for Petroleum Geology and Geophysics (NCPGG) and the School of Petroleum Engineering and Management (SPEM).
- ASP is one of only a few institutions in the world offering fully integrated teaching and research programs covering petroleum geoscience, engineering and management.

Source:
worldranking.blogspot.com

What Do Chemical Engineers Do?

Chemical engineers play a crucial role in everyday life. Chemical engineers are involved in the design, modification and operation of processes to produce desirable products. They are employed across a huge variety of sectors including: 

• Chemicals and allied products
• Pharmaceuticals
• Energy
• Water
• Food and drink
• Materials
• Oil and gas
• Process plant and equipment
• Biotechnology
• Business and management
• Consultancy

Chemical engineers must make decisions concerning:

• Which reaction pathway should be used to make the product?
• How to purify the desired product
• How to control the process and ensure it's safe
• How to make the process cost effective
• What should be done with any by-products formed?
• How to reduce the amounts of unwanted by-products formed
• What to do with unreacted raw materials
• How to recycle energy within the process

Here are some examples of job roles for chemical engineers: 

Project Engineer - Project engineers organise and run projects for engineering companies, this can be anything from managing a small modification to an existing pharmaceutical facility, to building a multi-billion dollar petrochemicals complex.

Design Engineer- The design engineer is responsible for determining how the process is to work. For example which pieces of equipment will be needed and how big they will be.

Operations Engineer - Operations engineers work "on site". This means that they spend their time ensuring that the plant is producing the right amount of product to the correct specification.

Research and Development Engineer (R&D) - The R&D engineer is innovative and creative. They develop the ideas for future plants, improving efficiency, environmental performance and even developing new products.

Coal Bed Methane Product Water

The quantity of the CBM product water: 
Extraction of CBM involves pumping large volumes of water from the saturated coal seam in order to release the water pressure holding the gas in the coal seam. What to do with this volume of often marginal-quality CBM product water is a source of much debate. Each well produces 5 to 20 gallons of water per minute. At 12 gallons per minute, one well produces a total of 17,280 gallons of water per day. It is common to have to have one well every 80 acres, and in the Powder River Basin, there are up to three methane-bearing coal seams. Therefore, there may be up to three wells per 80 acres.

The quality of CBM product water and its effects on soil:  CBM product water has a moderately high salinity hazard and often a very high sodium hazard based on standards used for irrigation suitability. Irrigation with water of CBM product water quality on range or crop lands should be done with great care and managed closely. With time, salts from the product water can accumulate in the root zone to concentrations which will affect plant growth. Saline conditions stunt plant growth because plants must work harder to extract water from the soil.
The sodium hazard of CBM product water poses additional threats to certain soil resources. Sodic irrigation water causes soil crusting and impairs soil hydraulic conductivity, adversely affecting water availability and aeration and subsequent crop growth and yield. Upon wetting of soils containing swelling clay, sodium causes the degree of swelling in the clay to increase, leading to dispersion and migration of clay particles. Current research at Montana State University shows that water with sodium levels equal to typical Montana CBM product water can degrade the physical and chemical properties of heavier, clay soils, making such soils completely unsuitable for plant growth.
The risk of sodium degradation has been observed in other soil textures. Jim Oster (personal com.) observed crusting, poor soil tilth, hardsetting and aggregate failure on a sandy loam soil irrigated with water with EC ~ 1 and SAR ~ 7. Minhaus (1994) saw irreversible and severe reduction in infiltration on sandy loam soil with long term irrigation under high SAR water followed by monsoon rain. 
There are many factors in addition to soil textures that affect infiltration rates. Mineralogy, lime, sesquiozides, organic matter content, cultivation, irrigation method, wetting rate, antecedent water content and time since cultivation all play a roll in infiltration. The only way to be certain of the impacts of saline/sodic irrigation water on the soil is to periodically sample and test the irrigation water and the soil.

Coal Bed Methane (CBM) and CBM Product Water (ex. in Powder River Basin

What is coal bed methane? 
The primary energy source of natural gas is a substance called methane (CH4). Coal bed methane (CBM) is simply methane found in coal seams. It is produced by non-traditional means, and therefore, while it is sold and used the same as traditional natural gas, its production is very different. CBM is generated either from a biological process as a result of microbial action or from a thermal process as a result of increasing heat with depth of the coal. Often a coal seam is saturated with water, with methane is held in the coal by water pressure. Currently, natural gas from coal beds accounts for approximately 7% of total natural gas production in the United States.

How do people estimate the amount of methane gas which will come from a region underlain by coal?  There are two popular methods of estimating recoverable methane gas from a coal seam.
a. One method requires estimating methane reserves by boring to the top of the coal seam, then extracting a core from the coal. The amount of methane recovered from the coal core is used to estimate gas content per unit volume of coal. If a number of cores are drilled and methane gas release is observed, one can estimate the amount of gas available in a region. The limitations to this method are:
1) there is much disturbance to the coal seam core before gas release is measured;
2) it is expensive
3) not every region of potential CBM development has been drilled and explored
b. Another method of estimation is through a series of calculations based on information already known about the coal in the region and the feasibility of CBM development. For instance, the Montana Bureau of Mines and Geology estimated the amount of recoverable CBM in the Powder River Basin using the following information:
•  A coal seam has favorable reserves if it produces 50-70 ft3 per ton of coal. 
•  CBM extraction is economical at 50 ft3 per ton of coal when a coal seam is 20 feet thick or more. 
•  Coal bed methane exists only in areas where the dominant chemistry of the water in the coal seam is sodium bicarbonate and where the coal seam is buried deeply enough to maintain sufficient water pressure to hold the gas in place. 
The Environmental Impact Statement for CBM development in the Powder River Basin estimated the amount of coal in the region based on the total reported tonnage of coal in the region multiplied by 50 ft3 of methane per ton of coal, irregardless of seam thickness, depth or proximity to outcrop. 

How do gas companies extract methane from a coal seam? 
Since CBM travels with ground water in coal seams, extraction of CBM involves pumping available water from the seam in order to reduce the water pressure that holds gas in the seam. CBM has very low solubility in water and readily separates as pressure decreases, allowing it to be piped out of the well separately from the water. Water moving from the coal seam to the well bore encourages gas migration toward the well.
CBM producers try not to dewater the coal seam, but rather seek to decrease the water pressure (or head of water) in the coal seam to just above the top of the seam. However, sometimes the water level drops into the coal seam. 


Are coal seams aquifers? 
Yes. Water flows through fractures (or cleats) in the coal seam and if the cleat system is well developed and has enough water to pump and produce an economically viable and feasible water supply, the seam can be an aquifer. Coal seams are the most regionally continuous geologic unit in the Powder River Basin and have aquifer characteristics equal to or better than sandstones, so are frequently targeted for water-well completions.

Spiral Wound Heat Exchangers

These heat exchangers have a broad temperature and pressure range and are used in single phase and two phase applications. They are able to handle many streams depending on the customers need. Pressures of up to 3625 psi can be handled sufficiently. The materials of construction of this exchanger include austenitic steels, aluminum alloys, carbon steel, nickel and chrome/moly alloys. This wide range of materials and the special features associated with the geometry of the heat exchanger allow for a wide range of applications. 
The surface area of heat transfer can be as high as 20,000 m2 but the maximum diameter is limited to 7,500 mm and a weight of approximately 260 tons per unit. It is possible to have larger diameters or higher weights but their feasibility has to be checked depending on the customer’s needs. 
The material of construction chosen depends on the customer’s needs. Simulations are The exchanger consists of a center hollow tube with tube bundles that spiral round it. The center tube and the tube bundle are housed in a metal column. The outer column does not have a uniform diameter. The bottom part has a larger diameter than the top part. Figures A and B show the outer shell and the tube bundles respectively. used for strength calculations of pressure containing vessels. Features such as tube spacing, tube support, bundle support and flexible mandrel are selected based on proven design technology developed over many years. 

Source:
Evaluation of LNG Technologies (by Valerie Rivera, Ayema Aduku, Oluwaseun Harris)

April 30, 2008 

Plate Fin Heat Exchangers

These heat exchangers are widely used in cryogenic application because of their low cost, small size, low weight, high thermal capacity and effectiveness relative to other types of heat exchangers. The result of the improved effectiveness is the achievement of true counter current flow where there is an increase in the temperature spread and a closer approach to ideality. This means that the refrigerant cooling curve is closer to the natural gas cooling curve. 
The exchanger is made up of manifolds or headers which consist of elements. A manifold and an element are shown below, Figures 4 and 5 respectively. An element is made up of a corrugated die-formed fin plate placed between flat metal separator plates. There are side bars along the outside of the fin sections. A stack of the elements is welded to form a rigid matrix and can be designed to meet any configuration and size. The stacks are welded onto the manifolds. Depending on the application, a number of manifolds can be assembled to form the heat exchanger.

 

Manifold or Header (xchanger.com)

An element

The wavy configuration of the fin promotes turbulence and therefore improves heat transfer. This increase in heat transfer is accompanied by an increase in pressure drop. This is a problem with low density fluids like gases because of the extra work required to surmount the pressure drop. 

Fin Configurations

This work is often much higher than the increase in heat transfer acquired from the fins. For applications where it is proposed any fin configuration other than the simplest, a thorough analysis of the effect on the system should be conducted.  

In designing the plate fin heat exchanger, it is possible to have different heights of the alternating fin plates. There is no requirement to have the same height or spacing of separator plates. This is a useful freedom to have in situations where the difference in density of the hot and cold fluids is large. In cryogenic systems, the refrigerant stream entering the expander has a higher density than the stream coming out of the expander. In such a case as this, it is necessary to use a larger height for the lower density stream so that a common Reynolds number and therefore heat transfer coefficient, U, can be attained.

Aluminum is the usual material of construction of plate fin heat exchangers for cryogenic applications. (Walker, 104-110)

Source:
Evaluation of LNG Technologies (by Valerie Rivera, Ayema Aduku, Oluwaseun Harris)
April 30, 2008 

Why Become a Chemcal Engineer??!!!

 1. What is chemical engineering?

Chemical engineering is all about change - chemical and biochemical engineers create and develop processes to make useful products from raw materials, in a cost effective and safe manner.

2. What does the work involve?

Chemical engineers are trained to apply fundamental engineering principles, maximise economic returns and reduce environmental impact. Chemical engineers need to work as part of a team and develop good communication skills. Strong problem solving and analytical skills are also a bonus.

World’s Best Chemical Engineering Universities

USA and Canada

1. Massachusetts Institute of Technology
   MIT is located in Boston, USA. MIT graduates and faculty are noted for their technical acumen (72 affiliated Nobel Laureates, 47 National Medal of Science recipients, and 29 MacArthur Fellows) and entrepreneurial spirit. The Department of Chemical Engineering at MIT have the largest chemical engineering faculty in the United States covering chemical engineering broadly, and in great depth. You may find further information about Che MIT here. For undergraduates, they have B.Sc degree in Chemical Engineering dan Chemical-Biological Engineering. For graduate school, they have M.S. CEP degree (Master of Science in Chemical Engineering Practice), Ph.D. CEP, and also Ph.D.
2. University of California – Berkeley
   UC Berkeley is located in Berkeley, a city on the east shore of San Francisco Bay in Northern California, in the United States. By the 1930s, Berkeley had established itself as a premier research university, and today counts sixty-one Nobel Laureates among its faculty, researchers and alumni.The College of Chemistry offers undergraduate degrees in chemistry, chemical biology, and chemical engineering, as well as double majors in chemical engineering and materials science and engineering, and in chemical engineering and nuclear engineering. A new option is a concentration in materials chemistry. The college offers doctoral programs in chemistry and chemical engineering, and a master’s program in chemical engineering, including a concentration in product development. You may find further information about chemical engineering at UC Berkeley here.
3. University of Toronto
   The University of Toronto (U of T) is a public research university in the city of Toronto, Ontario, Canada. The university is consistently placed among the leading academic institutions of the world. Newsweek magazine places the university first in Canada, and 18th worldwide, 9th among public universities, and among the top 5 universities outside the United States. The University is also affiliated with 9 Nobel laureates (6 alumni), the most of any Canadian university. Chemical Engineering and Applied Chemistry at the University of Toronto is one of the oldest and largest departments of its kind in North America. It has a rich history dating back to John Dalton of Dalton’s Atomic Theory and a modern reputation based on its state-of-the-art research achievements. You may find more information about chemical engineering at University of Toronto here

Polietilen

Ada berbagai macam polietilen berdasarkan beda massa jenis dan banyaknya cabang. Berbagai macam polietilen yaitu:

1.      Ultra high molecular weight polyethylene (UHMWPE)

2.      Ultra low molecular weight polyethylene (ULMWPE or PE-WAX)

3.      High molecular weight polyethylene (HMWPE)

4.      High density polyethylene (HDPE)

5.      High density cross-linked polyethylene (HDXLPE)

6.      Cross-linked polyethylene (PEX or XLPE)

7.      Medium density polyethylene (MDPE)

8.      Linear low density polyethylene (LLDPE)

9.      Low density polyethylene (LDPE)

10.  Very low density polyethylene (VLDPE)

Polietilen yang terpenting adalah HDPE, LDPE, dan LLDPE.