Engr MAA

Air System

2011-05-07T08:15:00.000-07:00

Here is something interesting to discuss on how to design air system in term it's capacity. It's basically on how to determine user's consumption. Users can be continuous users and intermittent users. Continuous users easily can be estimated since these users are consume continuously and no need to consider on oversizing the air system. However, there is some confusion in intermittent users. There are two different approaches in estimating the consumption for these users when designing air compressors. This intermittent users also classified as dynamic users sometimes. The first approach is by putting some weightage to the different users in percentage which will give lower consumption per unit user; it shows that the consumption is not fully utilized all the time. The second approach is by taking three single largest users without multiplying with any weightage. This is something very hard to clarify because of the subjectiveness. Lastly, any comments or criticisms are most welcome for our all understanding improvement.

Pressure Drop - Part 2

2010-01-13T05:17:00.000-08:00

In the previouse article, I wrote about good and bad pressure drop and briefly explained about why we care about it from the beginning stage and while operating the plants or facilities. Here I'll further share about how can we utilize the pressure drop.

The pressure drop again as highlighted in previous article is actually due to the friction along the piping. In the meantime, it is not a significant losses relative to equipments. As we all aware there is allowable pressure drop for all the equipments such a way that pumps or compresssors can be sized properly to reach destination pressure. All the equipments need to be sized so that the pressure drop calculated is not beyond the allowable pressure drop. How does usually this pressure drop is affected or can affect the size/design of equipment? It is exactly same as happen to piping but than much larger pressure drop relative to friction losses. So, it is actually same principal where the friction losses inside the equipment as higher velocity will give higher losses. For new design, the equipment can be designed so that the calculated pressure drop lower than allowable. Unfortunately, what would happen if the equipment designed is giving higher pressure drop than allowable? How it can be rectified? Does it mean that the whole equipment need to be revamped?

Pressure Drop

2010-01-07T05:17:00.000-08:00

What do we know about pressure drop? What is all about? Where do we see this pressure drop? Is it a harm or benefit? How to differentiate between good and bad pressure drop? Why do we need pressure drop? Where do we need it? When do we need it? Why is that so important to consider the pressure drop? What is the difference between allowable and calculated pressure drop? How pressure drop can be manipulated in order to get the optimum performance of equipments?

As we all know pressure drop occur due to friction factor and it can't be zero but can be minimised as happen to fouling. Similarly the pressure drop can be minimised as much as possible by using very smooth material of pipe. However, this is not practicale to use very smooth material of pipe or equipment since it would not be feasible economically for large configuration of plants or processing facilities. So far while this para, people might think about the harm and benefit of pressure drop and obviously only the bad thing can be seen so far as it all talk about how to minimise it.

Here is the time to talk about good and bad pressure drop. The pressure drop again needs to be defined properly so that can differentiate between good and bad. These good and bad actually reflecting to the allowable and calculated pressure drop. We should know how to manipulate the pressure drop so that good pressure drop can be gained. Before the good and bad pressure drop can be explained further, the allowable and calculated pressure drop need to be understood correctly. In direct way, substraction of the allowable and calculated pressure drop dictating the pressure drop is a good or bad pressure drop. Do you have any idea on this? Usually if calculated pressure drop is higher than allowable pressure drop, then, the excess pressure drop is considered as bad pressure drop. This scenario is further explained later by referring to an example.

The allowable pressure drop usually is defined from overall allowable pressure drop of the system/unit/line. This system, unit, or line can be defined starting from discharge point of pump or compressor to the destination point. So, the allowable pressure drop can be defined as substraction of discharge pressure and destination pressure. Greater the deviation between these values, better the allowable pressure drop. However, it is not economical to design very huge margin of allowable pressure drop. So, have you got an idea how this allowable pressure drop can be considered as good pressure drop? Let us explore!

Glycol Package

2009-12-27T01:57:00.000-08:00

What is the real function of glycol package? Why do we need this? Is that necessary to have this? Where it is located? Onshore? Offshore? What are the parameters that actually affect the performance of the glycol package which consists of glycol contactors and it's glycol regeneration skid? What do we expect if the feed conditions change in term of the performance of overall of glycol package? What should we do in order to get the optimum performance? When talk about performance, what are the parameters actually can be measured in order to get optimum performance? Which area that can be studied further if there is change in feed condition? What is the benchmark when do the optimisation?

There are lot of questions that can be raised for only simple package (I would say) compared to any other process technologies. Some people might say that first couple of questions is very fundamental relative to oil and gas industry. However, we should bear in mind that there might be some people never came accross in this glycol package before. Sometime different discipline might not really aware of this since they concern might be same regardless of the operation.

Overall picture of this glycol package can be read from GPSA section 20. However, those interested with the topic in surface and want to via this article and comment. You can do so. Experienced guys are welcomed to share their experience during designing or operation of this glycol package and very much appreciated.

Simulation Software

2009-11-30T05:53:00.000-08:00

Why do we need simulation software? Simulation softwares always consider the ideal condition, whereby in the real world, there is no such word of ideal condition. There must be some disturbances that affecting the system which cannot perform as it is. There are some people from non-engineering background but technical people always say this to most of the engineers. "We do the real thing in lab but you all only develop the model in the simulation softwares, how true it is?", this is some of queries (in proper manner) that non-engineering but technical people always say that to us, engineers. So, where are we stand at? Nod their statement? Or argue with them? Let us think to answer this.

Fuel Saver

2009-11-02T05:39:00.000-08:00

Now everyone is thinking of saving anything which ultimately would save money. Same goes to fuel consumption, where everyone is thinking of using more economical product. So, nowadays all big players which are competitors among themselves competing each other by promoting the more economical alternative ways. However, do the users really aware of the benefits of the product. So, any claims can be challenged by us as end user since most of the time, the customers are buying by referring to the advertisements which is actually giving more powerful impact than the real technology that is used in the product. Let us think what is the basis that been taken into account when considering the efficiency of the product.........

RON 95 & RON 97

2009-09-02T23:18:00.000-07:00

This newly introduced petrol with RON 95 has been launched recently to most of petrol station. It is not saying that RON 97 is not supplied to petrol station but as higher premium product which initially was only non-premium petrol. So, it is obvious that there is no any specific reason why it is classified as premium petrol but only because of the lower RON is introduced. People might question about premium petrol was sold when RON 97 was sold as non-premium petrol. The only thing is that about the quality of the product which requires more operating cost to produce it. Besides, people might wonder also why suddenly the price of RON 95 was increased by five cents compared to RON 97 when it was sold as non-premium petrol.

There is also some news polls by voting three categories such as comfort level of using RON 95 compared to RON 97. Some of them even don’t mind using RON 97 with increase of 25 cents which looks very small amount but cumulatively very huge. Interested people can refer to the poll result at http://polls.thestar.com.my/polls/result.asp?id=129&cid=2&cdesc=News. Some of them even simply not comfortable with using RON 95 with no basis. What really makes difference in determining the level of comfort to choose either RON 95 or RON 97? Is it because of lack of knowledge in term of RON content in petrol? If so, why not conduct some quick research on it by referring to the car’s manual and the history of RON.

This is not something to blame the public but knowledge accessibility about the fact that RON 95 is good enough as long meeting the specification described in the manual. This is not something not aware by public only but also by authority that introducing all those RON 95 which they themselves don’t have basis why it is introduced and what actually term premium petrol stands for. It’s again very important to know the basis when finalizing any decision especially when purchasing something.

HX Design - BEU and BFU

2009-08-27T23:44:00.001-07:00

It’s very hard to see design of heat exchanger with configuration of BFU in the industry. Whereby this configuration or F-shell has its own advantage when using compared to BEU configuration. It’s again because the designer, client, owner, and whoever in the position deciding the configuration has a tendency to choose BEU. Usually when deciding on choosing the configuration, the process stream properties will be considered such as temperature approach, fouling resistance, fluid phases, etc. Issue on temperature approach will be discussed in detail here since BFU has its own beneficial to get desired temperature even the temperature approach is very low and sometime even the temperature cross happens. The TEMA configuration for BEU and BFU is shown:-

Usually when temperature cross happens, BEU configuration will be used in series to cater issue of very low temperature approach or temperature cross. This is very common to happen because the designer or the decision making authority more convenient to use series of BEU heat exchanger. There is no any other engineering reason but only based on their experience. So, if thorough engineering study is conducted some other alternative might be able to be considered such as by using BFU configuration. The only different is that the longitudinal baffle that separating the shell into two sections which is ultimately separating the inlet and outlet of shell side fluid.

Some people might say that issue on temperature cross can be resolved if the flow is counter current. However, the true counter current is not achieved in E shells if the tubeside pass is only one pass but again not to be forgotten that pressure drop across the tube should be utilized to increase the velocity of the tube side which eventually enhance the heat transfer coefficient of tube side. So, by considering the minimum number of passes as two passes, the true counter current cannot be achieved if there is no any device separating the fluids between tube and shell meeting as co-current. Here is typical configuration of BEU heat exchanger with its flow as shown:-

So, it’s again very important to consider BFU configuration which actually might give lot of impact to economic of the heat exchanger to be purchased or fabricated. It’s not that BEU in series cannot be used but on apply existing shell type not fully utilized when some circumstances such as very low temperature approach or temperature cross persist.

Rule of Thumb

2009-08-20T01:07:00.000-07:00

Rule of thumb basically means the experience on doing any particular job by applying the standard or reference. The variety of rule of thumb is varies among different people according to their experience. Different discipline engineers will have different rules of thumb that applicable to their work. For example, chemical engineers might have their rules of thumb when designing any process equipment. Piping engineers might have their own when routing the piping. The application of applying this rule of thumb mainly in engineering design work can shorten the time required to design.

This rules of thumb is mainly comes from research done by any institute such as American Petroleum Institute (API), Tubular Exchanger Manufacturer Associates (TEMA), etc. In addition to this, there are also from experience of the engineer him/her self all this while doing the design work. For example, pressure drop across the shell and tube heat exchanger is roughly about 0.7bar which typical value is allowed when designing it. This is purposely made so that the pumps that pumping upstream of the heat exchanger can cater the required pressure drop. There are no specific standards telling so, but from experience of people designing heat exchanger. Some people might say 1.0bar also can be considered. Some people might give more stringent value which is 0.3bar. So, if there is argument in deciding the value, it’s better to refer to the design basis that agreed by the team for that particular project.

The rule of thumb is basically would give some flavor of the rightness when getting the result. It is not only giving the standard to be used but when converting from one unit to another unit. For example, natural gas that having molecular weight 19-22kgmole/kg will give 1mmscfd equal to 1000kg/hr. Again this type of rule of thumb can be cross checked with simulation data to verify it. However, as we all doing the work with simulation interference, this can be on our finger tips.

Finally, this rule of thumb can be used to design any new equipment if you are referring very established sources such as TEMA, API, etc. That rule of thumb from your experience can be used to quick check of the calculation.

MAN Turbo to Supply Compressors to Abu Dhabi

2009-08-06T19:37:00.000-07:00

MAN Turbo AG of Oberhausen (Germany) has been awarded a contract for the supply of nine compressors to the value of around €60 million to the emirate of Abu Dhabi for the expansion of the Thamama-B oil field. The purchaser is the Abu Dhabi Company for Onshore Oil Operations (ADCO). The contract forms part of an overall project awarded by ADCO to SK Engineering and Construction (SKEC) of Seoul as the general contractor.

The contract that has now been signed relates to the ‘Bab Gas Compression Project’ and focuses on the expansion of Thamama-B, one of the five most important oil fields in Abu Dhabi. ADCO thereby aims to increase its production from the existing field considerably, thus further helping to safeguard the country’s energy supply. Over 94% of the United Arab Emirates’ total oil and gas reserves can be found in Abu Dhabi. The emirate has the world’s tenth-largest gas reserves.

In addition to the tendered compressor technology, the short delivery times agreed were a key factor in the award of this contract to MAN Turbo. ADCO, the biggest oil and gas producer in the United Arab Emirates, wants to commission the installation as a whole by 2011 and increase its yield from the existing field substantially by the year 2030.

The compressor trains manufactured by MAN Turbo at its Berlin plant are used in so-called gas collecting stations. Three compressor trains operate in each of the three stations. The incoming gas is conducted there to the compressor trains, which increase its pressure. The gas is then transported via pipeline to the Gasco refinery in Habshan for further processing.

For MAN Turbo and SKEC, this is the first order for ADCO. The two companies have successfully handled a similar contract in Kuwait in the past. “We are supplying compressor technology to Abu Dhabi for ADCO for the first time. This gives us a good foothold for further activities in this region. The Middle East with its emergent economy and its important oil and gas industry is of great strategic importance for our company,” said Dr Gerhard Reiff, a member of the MAN Turbo executive board.

Source: www.gulfoilandgas.com 7/27/2009, Location: Middle East

Runway Reaction

2009-07-30T20:16:00.000-07:00

Runaway reaction happens in a reactor most of the time if proper handling not considered during handling chemicals, operating plant, abrupt climate change, etc. This runaway reaction can be categorized as two runaway reactions; marginal and non-marginal. This is because of the allowable margin during design to allow some operating envelope fluctuation. This fluctuation to the operation might because of the abrupt climate change during monsoon season. Besides, upstream unit operation also can cause some fluctuation to downstream and eventually causing runaway reaction.

Marginal runaway reaction is expected to happen during normal operation and can be adjusted or corrected by applying relieving system. This marginal runaway reaction some time might cause unwanted incident but still in tolerable limit. However, there is a case whereby the incident caused to fatality due to some leakage and sudden pressure relief and cause explosion. This is not only happening for the new cases or process technology but even repeating incidents keep on happening from time to time.

There is non-marginal runaway reaction whereby the runaway reaction happens due to negligence of the operators, supervisors, engineers, and up to plant general manager. This is because of the discipline in following the procedures available in plant are not fully complied when operating the plant. This is eventually can cause to the runaway reaction which ends up with losses of dollars and brings to fatality. This kind of accident is not only releasing the hydrocarbons to atmosphere but explosion which made a vessel like a rocket shooting up to the sky. So, all the procedures which are available in plant must be followed even it sounds tedious procedures eventually can give big impact to the plant quality.

So, as time go on, technology also developed and there are chances to repeat the similar mistakes that happened before for different technologies. People might say that it’s very hard to stop the accident from happen but actually all these accidents caused by runaway reaction can be reduced which by reducing human error. This human error can be reduced by practicing the quality management of the plant operational. This is can be done by emphasizing the use of operating procedures with systematic by really follow the work flow given in organization chart. Besides, the authority delegation also must be looked into seriously to avoid any careless mistakes such as signing off permits without checking it properly. It’s again depending upon attitude of the personnel.

Competitive World

2009-07-15T00:49:00.000-07:00

Everyone are competing to be the best and the first in supplying goods, equipments, services, consultancies, etc. In this competitiveness, the end user is the one will benefit. Everyone is competing everywhere in getting job and satisfy the customer. Even not going into detail engineering world, competitiveness can be seen in retail industry where the products are high demand if economical and quality. So, from this competitiveness, grow the innovation where the research is being done to improve the quality compared to existing technology.

Starting from small items such as chemicals for treating until very proprietary processes, there are very huge competitions to get the customer. Those days, it’s very hard to get any licensor for any particular niche technology but today the similar process technology with innovated technology can be found anywhere. Again the customer will get the benefit in getting the best product in market.

Sometimes the customer or the plant owner needs to perform study properly so that the ultimate objective can be achieved. This is basically to avoid any losses to the production as highlighted in previous article which caused losses of diesel due to jellying.

Alternative Energy

2009-07-03T01:57:00.000-07:00

Everyday people in every corner in the world are talking about alternative energy or renewable energy. This is not something that people not realize of it but more viability of develop it. This is because of the current situation with availability of fossil fuel, every one chasing to produce oil and gas. The demand also increases as the oil and gas not only used for fuel purpose but also for other derivative products from these oil and gas. All these derivative products are being used everywhere starting from small baby to variation of age of people. We might not really realize on this if not really dealing with petrochemicals where all these oil and gas based products are produced.

Demand for fuel is keep on increasing from time to time, country to country, etc. This is because of the world circumstances where everyone all over the world is utilizing the fuel. We might see in last 15 years, all Chinese in China are using bicycle to move around and very few using cars or bikes. In those days, America is the largest importer and user of oil compared to other region. Recently, off shoring of job is being practiced everywhere to cheaper place. From there everyone starts realizing the important of urbanization and higher living style. Nowadays everyone competing to reach the highest living style which give better lifestyle and sometime not necessarily. So, as the demand increases from time to time and the source is kept on depleting, there must be something to be done to cater energy demand in future.

As the demand increases, everyone is talking about alternative or renewable energy. Sometimes is not really works if the big player such as Shell, Exxon, PETRONAS, Chevron, etc really keen to invent in this alternative energy. However, it can be seen that some of the country still using some of alternative energy for very minor application. Alternative energy like wood, animal dunk, wastes, etc are still being used but not really in commercial scale. For example in India, people quite often use animal dunk as a fuel for many applications.

So, it’s again depending upon the initiative taken by anybody to fully utilize the sources. The direct gas such flaring always has been an issue to come out with zero flaring. However, this is something that very subjective to the law. This is because of the viability of the process with current sources. So, the only way is that by enforcing the law to the operating company to come out zero flaring. For time being this initiative is only considered to produce money rather than comply with obligation of zero flaring. Same goes to waste management in landfill whereby the methane produced is simply flared or vented to atmosphere. This can be monetized if waste management company willing to take initiative to use it as fuel source.

Chartered Engineers

2009-07-01T18:34:00.000-07:00

There was question raised in previous article on BEM and IEM regarding the necessity of registering with BEM and/or IEM if registered with some other body such IChemE, AMechE, SPE, etc. Again as an engineer must realize that they are not really professional engineer if there are chartered respective disciplines.

By right it is a regulatory mandatory with Board of Engineers, Malaysia (BEM) if practicing engineering and wants to be certified as professional engineer. In the mean time, engineers can practice parallel to be certified as chartered respective discipline engineer too.

Currently there is no enforcement yet on registering with BEM in Malaysia but as a preparation for facing new challenge as a develop country we as an engineer need to be qualified not only by degree but also acknowledged by regulatory body such as BEM.

Jelly

2009-06-27T00:30:00.000-07:00

Jellying is something bad stuff that might occur when dealing or processing liquid most of the time. It might occur directly or indirectly along the process line or even during the storage. Proper guideline is very necessary when dealing with production that having more than one train and even having slightly different configuration. The configuration might not be big difference on the process technology but there might be small differences in using the chemicals when injecting them to prevent corrosion, fouling, or waxing. This eventually will give big impact on the products.

This jellying is not only might occur due to temperature difference but due to different chemical presence in the different train which end up to the same storage tank. This is mainly because of the different chemicals used might cause undesired reaction which gives emulsion to the mixture of different streams. This emulsion eventually might give billions of dollar losses. So, it is really important to evaluate the proper chemicals to be used if there are more than one trains that streaming to same storage tanks.

This is crucially important when dealing with different vendors for the chemical supply. Sometime the owner or operator might want to see the significant benefit from different vendors which might end up with something bad stuffs. So, as a owner of the plant, need to conduct small lab analysis of emulsion for different chemicals sources. Or, the owner might use only vendor at one particular time to see the significant benefits.

Some people might argue that this might be very ridiculous mistake that can be done by human being. However, this is the fact that human errors are come from very ridiculous errors which end up with quite significant impact. This is phenomenon has happened in one of the plant or refinery which caused million dollars losses and some of end users sued the refinery due to consequent impact to their equipments. Luckily the product sold off is not fully distributed to the end users and remedies are given to the affected end users.

Since this already had happened in the refinery/plant itself where they have their own expertise in that particular area. So, there is possibility of to happen it again in end users since there is using different products from different supplier which can cause similar phenomena. This is not simply postulate done from the incident happened in plant/refinery but can be seen lot of cars, machineries, etc that end up with blockage of fuel line and need quite frequent cleaning or maintenance.

Sweet Sour Crude

2009-05-25T07:21:00.000-07:00

How many people those really realize of this sweet sour crude? I would say that many of them not really aware of this sweet sour crude. Many of us have heard of sweet sour fish, sweet sour chicken, etc, which is actually reflecting the type of cooking. However, in oil and gas industry these are totally different categories which reflecting lot of differences. Those differences in fact not really recognized even by those personnel from oil and gas industry. Again, oil and gas industry is not really a small scope of world which can be understood by all the personnel from the industry.

There are different levels of understanding of this sweet and sour crude. Some might say that sweet crude is more expensive than sour crude which is right and they are not really sure why that is so. Besides, some people might say that refinery configuration would be different in term of the process involved which is also absolutely right. There are people would say that sour crude is nasty crude whereby sweet crude something good crude. All these are absolutely correct but there is a reason why those people saying so.

The main culprit that causing this nattiness is actually all those unwanted gaseous such as carbon dioxide (CO2), sulfur, etc that need to be treated before further processed. So, the main difference to the refinery is that additional unit area which requires additional cost. However, it does not mean that the sour crude is unwanted crude relative to sweet crude. Obviously the sweet may not to be treated to remove all those unwanted gaseous since it is within allowable limit to the downstream unit where the rest of refinery taking place such as reforming which is actually the main process to convert long chain into aromatics which gives the higher octane number.

Industry vs. Academic

2009-05-17T05:06:00.000-07:00

Industry and academic are very interrelated between both two. As in engineering world, they need to be some collaboration continuously in order to invent new technology which at the end will be used widely and benefited by both two sectors.

This is very crucial because of the continuity of the technology which actually is contributed from either area where any small scale or lab result that is done by academic which from university later will be used by industry to maximize the profit of the company as an ultimate objective. This is again is not something that any industry can straight away take any formulation or research done by university but there will be some agreement such as industry or more specifically an identified company that willing to pump in some fund to make move the research or development to be done without any monetary burden. This is because of the insufficient fund for academic or university stopping them from moving on with any new innovation to be invented.

In addition, there is necessity also from industry people as alumni to support their school they graduated from at least from knowledge or experience to enhance the syllabus of the school/university so that can ease the accreditation process for the related department of engineering. This is the reason why almost all the faculty that contributing growth of industrialist will have at least one industry advisor. Besides, there would be cases where academic will invite industry people to evaluate for the final year project of the students. This is really important because of the feedback that will be highlighted by them usually more than practical rather than totally theory.

Last but not least, there are some limitations to make them collaborating these areas because of some agreement issues or understanding arguments. This is the reason both industry and academic need to clarify all the commercial issues to avoid any misunderstandings. So, in order to avoid any confusion both parties should really clear of the contract of agreement.

Inspection – Preparation

2009-04-19T17:45:00.000-07:00

Here are some guidelines on preparing prior to inspection mainly those engineers are considered young engineers. Experienced engineer would know what to be asked or recorded during the inspection and obviously know what to prepare prior to inspection visit in site.

An engineer need to know what the equipment to be inspected obviously and any related documents to the equipments need to be brought. This is crucial because to have some understanding of the inspection process. One of the main documents that need to be brought while in site is obviously are drawings. Drawings like process flow diagram, (PFD), piping and instrumentation diagram, (P&ID), isometric drawing, and assembly drawing are really important while conducting inspection. This is because of the identity of the equipments, layouts, etc are provided in drawings. So, it would give the some idea on the internals of the equipment such as baffles, wire-meshed, inlet device, etc.

Sometime most of the preparations are done perfectly but still sometime there is a circumstance where the major license that need to have forgotten to take which is confined space entry permit. This sometime would cause unnecessary delay to overall project deliverables. This mainly happens for those had conducted any inspection during last turn-around and thought that there’s still valid but unfortunately it is already expired. So, it is advisable to cover this requirement as a part of checklist and put it as first priority.

Inspection

2009-04-14T23:35:00.000-07:00

Inspection can be done for two main reasons; first for periodic check-up as human being is recommended to do medical check-up and second if there is any rectification to be done to the system as human being as well where need to go for medication.

The inspection wills actually reflecting the performance of the plant or platform in term of downtime. As for shutdown, there are planned and unplanned shutdowns. So, during the planned shutdown there will be couple of teams conducting inspection for identified equipment for respective department. Obviously department such operation, technical service, maintenance, and inspection will take part as main role player. Inspection during planned shutdown usually will be taken part by almost all of the engineers from respective department. Unplanned shutdown usually occur due plant upset where unexpected than planned happens. So, the team for the inspection will be called usually as root cause analysis, (RCA) team. For this kind of inspection, usually there will be one engineer from each department.

Inspection for planned shutdown usually will take place as mandatory for Department of Occupational, Safety, and Health (DOSH) requirement to conduct inspection during the turnaround (TA). During this period of duration, related vendors also take part to inspect. As an owner of the plant, all the observations and findings will be recorded to investigate the process behavior. Normally technical service department will do all this since most of the troubleshooting will be done by this department which acts as internal consultant for the plant. The rest of the departments might look into the findings mainly on the physical of the equipments in term of the welding, joint between connection, thickness of the wall of the equipment, etc. From all the findings, respective departments will come with the recommendations or conclusions in order to rectify it before the equipment is boxed up. For example, inspection to the shell and tube heat exchanger might be found with slurry that stagnant at any corner of tube or shell. Prior to this inspection, operation/production department might have faced problem in achieving desired temperature due to inefficient heat transfer. So, further study will be conducted so that fouling in future can be reduced so that won’t affect the performance until the next turnaround. The heat exchanger might be redesigned so that minimum velocity can be achieved so that the liquid can form turbulence enough to move any possible materials along the tube or shell. Besides, for those young engineers that desired to be design engineer can be credit since have seen the real internal part of the equipments. From there, the young engineers can take some reasonable margin or consideration when designing the equipments even not highlighted by theory.

Inspection during unplanned shutdown will be conducted in order to rectify the problem faced that causes plant upset. The RCA team will conduct a study on factors and solutions and present it to the management whereby there is no presentation to the management during inspection for planned shutdown. There will be a leader selected by plant general manager to lead the study which usually from technical division that familiar with the process involved. Historical data for the operation will be studied whether the operation follows the operating envelope while operating the plant. Typical cases for this unplanned shutdown and inspection are tube ruptures for furnace and heat exchangers.So, both inspections are really crucial for all generally and those young design engineer specifically since the real equipment can be seen in term of physical appearance and problems faced. If there is any chance to get involve, then it is recommended to grab the opportunity. It might be harshly and messy but will be end up with fruitful experience and knowledge when designing any equipments.

BEM and IEM

2009-04-13T19:44:00.000-07:00

Engineers practicing (Malaysia) engineering must register with Board of Engineers, Malaysia (BEM) in order to acknowledge their experience when certifying the engineers to be professional engineer. The number or years acknowledged by BEM is the year started from the date registered with them. In order to certify an engineer as professional engineer, the engineer must have at least three years experience (acknowledged by BEM).

People might wonder if BEM is the one giving certification for professional engineer, what goes with Institutions of Engineers, Malaysia (IEM). So, the main difference between these two is that IEM is learning organization for engineers. In order to get privileges from IEM, an engineer need to register to be member first and there are a lot of membership types. Engineers need to register to be graduate member to start getting privileges in term of trainings, industry exposure, etc. Differ from BEM, IEM recognize experience from the graduation date.

In order to upgrade the membership from graduate member to member, the engineer needs to practice engineering work which consists of design, site, project management, etc for at least three years. The work was done by the engineer must be supervised by an engineer that member of IEM (MIEM). So, this supervision can go in two different ways; direct supervision if the engineer (MIEM) and graduate engineer in one organization and indirect supervision by mentoring scheme or log book scheme. After practicing minimum three years of working experience from the date of graduation, the graduate engineer can apply for professional interview (PI) in order to upgrade the membership to MIEM. Then, engineer with MIEM can apply for professional engineer with BEM if the number of years experience meeting minimum three years requirement.

RAM Study

2009-04-13T18:58:00.000-07:00

Reliability, availability, and maintainability (RAM) study is a method or approach that being used in many industries many years ago. This is mainly because to optimize the reliability of the system so that can reduce the downtime of the system which eventually causing loss of production. So, by conducting this RAM study operation people will aware of the availability of the equipments respect to the system and maintenance team is aware with maintenance job need to be done. This RAM study is important so that the system reliability is reliable enough to produce the products as in agreement with customer.

There are lot of software are offered in market nowadays that claim can deliver the RAM study with minimal time consumption. However, there are skills needed when developing model for the RAM study. The model usually will be modeled with reliability block diagram (RBD) or fault tree diagram and the approach or basis of both diagrams are really dependent of the engineer develop it. Both diagrams will be modeled by referring to the process flow diagram to demonstrate the continuity of the process. However, it is more recommended to develop RBD which will give more information as a result and definitely need more info to key in when developing the model.

This RAM study usually will be done in a workshop where all personnel will be in during the session. If anyone realize this session almost like hazard and operability (HAZOP) study. So, those attended or conducted the HAZOP study might realize that if the leader/chairman prepared some draft of the node to be studied would be easier to carry the HAZOP workshop. Otherwise the session would be lengthy if the node to be identified during the workshop and there will be a lot of conflicts among participants. So, it is recommend as RAM workshop leader to construct the model prior to workshop and during the session all the information will be added as the workshop goes on.

In order to be leader/chairman for the RAM workshop, he or she needs to attend couple of RAM workshop as HAZOP chairman needs to be really experienced personnel. This is because the leader should know how to raise the issue related to any systems or equipments. Similar to HAZOP study, the chairman must be able to prompt the participants to extract the information so that can be documented during the workshop.The result or conclusion is again dependent on the input that was given to the software to run it. These RAM study software will use Monte Carlos approach to simulate probabilistic statistic and will give some figure for all three; reliability, availability, and maintainability in term of probability. Normally this probability must at least more than 90% and this is even considered as bad system that having only 90% reliability, availability, or maintainability. As HAZOP, this RAM study is only method or approach to predict any contingency plan to avoid any bad downtime.

Slugging and Pigging

2009-04-06T22:41:00.000-07:00

Slugging and pigging are normal terms commonly used in oil and gas industry, more specifically in upstream rather than downstream. This is mainly because of the different phases of fluid with presence of other materials such as sand. Because of this slugging phenomenon, there is equipment called slug catcher to catch all this nasty stuff by stabilizing the fluids from the reservoir.

In other word, this slug catcher also can be said as stabilizer (some might not agree and it depends how they interpret it) since stabilizing among oil, gas, and water until reaching certain acceptable content level.

This slugging usually takes place when there is either liquid/gas in gas/liquid when form a pocket and starts hitting the wall of the pipe. This at the end actually will shorten the life the piping and causes more frequent maintenance which actually increases the downtime of the plant or platform due to unplanned shutdown. Besides, solids such as sands, wax, and impurities sometime can cause harm to the pipeline which can increase operating cost by increasing pumping cost due to rough surface of the pipeline. So, there must be some alternative need to be taken before the problem exists or during the operation. Slug catcher usually will be installed upstream of the most of unit operation to stabilize the crude to be processed. However, even lot of action has been considered there is also problem persists which end-up with some operational issues such as pressure loss, off-spec products, etc. Once the problems found during the operation then the pipeline need to be rectified.

Pigging is usually a common used method during construction and operation. During construction the pig launcher play a role such that the pigging process can be used for debris removal (onshore and offshore), gauging, measuring, cleaning, flooding for hydro-test, dewatering and drying, and some other specialized applications. During operation the pig launcher is being used for product’s separation (if batch process is carried out for different products), wax removal, line cleaning, condensate clearance, corrosion inhibition, meter proving, and some other specialized applications. So, this pigging is one of method commonly used to prevent, monitor, and rectify any slugging consequences which can cause to the shutdown of the plant/platform.

GA Drawing

2009-03-31T01:39:00.000-07:00

GA sounds like GH but here is General Assembly which is very important when designing plot plan. This GA drawing is basically a product from plot plan design. This GA drawing will be used from the beginning of the plant/platform until infinite. This is because of the necessity as guidance for space availability. From this GA drawing most of area related to design need to be considered such as pipe rack coordination, pump location, maintainability, equipment installation, hydraulic calculation, etc.

The pipe racks really important when designing the piping route which really dependent to GA drawing which eventually will dictate overall of the process stream. This is because of the products processed are being transported through piping from one unit to another unit (processing area or storage). Besides, this GA will give some idea on the restriction area to be routed such as road access which will affect to the safety and end up with lost time injury, LTI. As everyone aware, nobody wants LTI to be recorded to show the credibility of the company.

This GA drawing will assist a lot in term of pump installation when taking into consideration of the net suction positive head. An engineer can know some idea on the location to be located when deciding the new pump during any expansion.

In addition, this GA drawing also can be used for the preparation of both owner and contractor when planning for maintenance works. This is really crucial when the works need some cranes or fork-lift which is commonly used during the maintenance work usually during turn-around. Besides this machinery they are also some other considerations need to be taken into account. For example, space availability for cleaning any tube bundle which is really common thing to happen during turn-around.

As highlighted for pump installation it goes similarly for new equipment to be installed when new expansion or initiative implemented. This is again will dictate to identify the area where the equipment to be installed before verifying it at site. This will also tell whether the equipment to be installed to be totally new big equipment or just a baby equipment to cater additional capacity. The space availability sometimes can control the design of the equipment for expansion.GA drawing will give the dimension of the distance and the size of the equipments (length and width) which actually can be used for hydraulic calculation as a rough estimation to make judgment on the routing the piping or installing the new equipment.

Confined Space

2009-03-16T00:40:00.000-07:00

Confined space by meaning itself means that very limited or closed area. From the definition, what can be seen that something present in very few quantity which is oxygen in this case. This is the term used in oil, gas, and petrochemical industry. This is actually as requirement for personnel when dealing with entrance of the unit operation. All the personnel that involved must have entrance permit to confined space which will be issued by the doctor examined the personnel to assure that he/she is fit to conduct the job.

This confined space must be blown with air by blower in order to sustain the oxygen content so that personnel inside can breathe as usual. Besides, when entering the confined space, personnel must present their identification card to hole watcher or safety officer. This is mainly because of the safety consideration that needs to be addressed so that can monitor number of the personnel in that particular equipment to avoid crowd.

People might be asking why respective personnel need to enter the equipments and when they have to. This is mainly done during turn-around where the plant (mainly downstream) will be shutdown as planned shutdown to inspect the equipments such as vessels, towers, reactors, etc. It is not only conducted during planned shutdown but also unplanned whereby unwanted scenario happens. This is basically happens during plant upset or any unit operation upset due to any failure, rupture, leakage, etc. Therefore, there must be somebody need to go in the affected equipment(s) to inspect any findings could be observed. From the findings found, there would be some initiatives to be taken to rectify the problem and come out with plan to prevent in future.

People might be asking also why need to go inside the equipment even there are monitoring (corrosion) points as given the diagram below. Unit operation might have all those indicators but most of the time the indicators only can show us the result of from the impact such high pressure drop, off-spec product, corrosion behavior, etc. So, in order to rectify it related personnel from operation, maintenance, and inspection need to go inside to conduct detail study.

Here are sample of the signs that can be seen near to area that classified as confined space and require permit to enter with presence of safety officer.

Corrosion Monitoring

2009-03-12T19:53:00.000-07:00

Corrosion is a natural phenomenon which will occur but will vary on the rate depending on the environment and the material. Corrosion not only taking place in industry generally or oil and gas specifically but also everywhere which are not really noticed by human being. For instance, many of car manufactures are having some sort of antirust which giving some coating on the surface of the car body to prevent from corrosion taking place. This antirust scheme is not a whole life guarantee given by them but just for some time only. What can be seen from here is that the coating mechanism only can sustain for limited time only and again need to be coat again with the presence of car polishing companies. So, even coating mechanism itself facing corrosion problem where they lose of the coating film on the car body. Here where the material taking the action but some other scenario where environment will take action. For example, those cars exposed to beach area more prone to corrode since the environment is corrosive.

Corrosion is everyone issue which need to be addressed by everyone, everywhere, and every time. However, the corrosion that taking place in industry is more severe compared to non-industry related. This is mainly because of the function of itself where in industries, corrosion like a culprit to production. If the corrosion persists, the production line has to be shut-down since the safety always become on the top priority even ultimate aim of industries are to make profit. Therefore, there lot initiatives have been taken and being done in all level to monitor the corrosion. This mainly to study the suitable material to be used in related industry and way of minimizing the rate of corrosion. There are lot of proprietary chemicals are being used as a corrosion inhibitor to inhibit the corrosion. Again this corrosion can behave very differently for different application and they need different chemicals as a corrosion inhibitor. There is detail study to be done when procuring any vendor chemicals to avoid any off-spec products which can cause billion dollars losses. Thus, corrosion monitoring is important to identify the behavior of the fluid exposed to the material (piping, vessel, etc.). There are many ways of monitoring and one of it has been discussed on corrosion coupon. In addition to that, electrical resistance (ER) and linear polarization resistance (LPR) also have been successfully applied and are used in an increasing range of applications.

ER probes can be thought of as “electronic” corrosion coupons. Like coupons, ER probes provide a basic measurement of metal loss, but unlike coupons, the value of metal loss can be measured at any time, as frequently as required, while the probe is in-situ and permanently exposed to the process stream.

The LPR technique is based on complex electro-chemical theory. For purposes of industrial measurement applications it is simplified to a very basic concept. In fundamental terms, a small voltage (or polarization potential) is applied to an electrode in solution. The current needed to maintain a specific voltage shift (typically 10 mV) is directly related to the corrosion on the surface of the electrode in the solution. By measuring the current, a corrosion rate can be derived.