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Technical aspect of feasibility study

Technical Aspect of Feasibility Study based on My Actual Experience

There are at least two aspects that make a feasibility study sounds: technical aspect and financial aspect. In this post I want to share you the first one: how to make technical aspect of feasibility study.

I have involved in three feasibility study projects. Each project has different technical aspect that being focused. I want to be more practical in this post, so I will share you example of what to write for technical aspect of feasibility study based on my current project.  Read More

Pipe wall thickness chart-3

Pipe Wall Thickness Chart

Pipe wall thickness chart is a must-have item for me as process engineer. I usually use it when I have to size pipe, do hydraulic analysis, etc. Information I need from the chart are mostly outside diameter and inside diameter of particular pipe size.

In this post I want to share you pipe wall thickness chart based on ASME B36.19M-2004 Stainless Steel Pipe.

In this chart you can extract data of

  • Outside diameter and wall thickness in inch and mm
  • Pipe size is expressed in NPS (Nominal Pipe Schedule) and DN (Diametre Nominal)
  • Weight in pound per linear foot or kilogram per meter

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Safety Valve vs Relief Valve (Differences based on API 521)

Sometimes terms can be confusing. Terms safety valve and relief valve are confusing too. So, to make it clear, let see the definition based on API 521.

Pressure relief valve is a generic term applied to relief valves, safety valves, and safety relief valves. It is designed to automatically reclose and prevent the flow of fluid.

Relief valve is a spring-loaded pressure relief valve actuated by the static pressure upstream of the valve. The valve opens normally in proportion to the pressure increase over the opening pressure. A relief valve is used primarily with incompressible fluids.

Safety relief valve is a spring-loaded pressure relief valve that may be used as either a safety or relief valve, depending on the application.

Safety valve is a spring-loaded pressure relief valve actuated by the static pressure upstream of the valve and characterized by rapid opening or pop action. A safety valve is normally used for compressible fluid.

Can you spot the differences?

Relief valve is used for liquid and open in proportion to the pressure increase, while safety valve is used for gas and open rapidly.


API 521 Pressure relieving and depressuring system


First Experience Involved in Plant Register Project

Two weeks ago I had a workshop in Yogyakarta. The intention of the workshop was to finish and close one of my company’s project which was plant register project for one of geothermal field in Indonesia. Actually I am not official member of this team. But my boss wanted me to join the workshop to fulfill the quota.

Although I am not official team member of this project, project manager of this project asked me to help. Before I joined the team, I thought the project was simple enough because it involved only three person plus one non-dedicated person (not 8 hours/day, 5 days/week doing the project). Then, I changed my mind. The project needs more people. Read More

Submerged Turret Loading Buoy

LNG Regasification Vessel Requirement based on DNV Classification Notes No. 16.3

In previous posts, I shared some of onshore LNG terminal and regasification system. How about offshore LNG regasification system? Does it have any differences with onshore regasification system? In this post, I want to share you practical guidance of offshore regasification vessel from DNV (Det Norske Veritas) Classification Notes No. 16.3. DNV Classification Notes No. 16.3 is applicable for all vessels engages in LNG regasification.

Regasification vessel is intended to regasify LNG then delivered the gas to pipeline gas grid, through a Submerged Turret Buoy or through dedicated export manifold. The Classification Notes specifically explains regasification systems and offloading systems for natural gas through submerged turret buoy offshore or through dedicated gas unloading manifolds. Read More

Water treatment plant balance

Water Treatment Plant Capacity Calculation

In this post, I want to share you how to calculate water treatment plant capacity. I used this term to avoid misunderstanding.

  • Raw water is untreated water coming from water source, such as from wellwater, river, or seawater
  • Utility water is raw water which has been treated and used in plant, such as for personal hygiene (flushing), utility station, cooling tower make up
  • Potable water is sufficiently high quality water which is provided for drinking, cooking, laundry, and safety shower/eye wash
  • Demineralized water is treated water which is usually used as chemical dilution of MDEA or boiler feed water

Water treatment plant capacity calculation begins with demin water demand, potable water demand, utility water demand, and the last is raw water demand. Read More

Typical Content of Feasibility Study

Many people visited my blog because they searched about feasibility study. I wrote a bit about the topic years ago. I wrote it when I involved in my second feasibility study project, which is bankable feasibility study for ferronickel smelter.

In this post I want to share you typical content of feasibility study. The content actually may be different from one another, depends on the topic. But, after I involved in two previous feasibility projects and current project, I learnt that there is similarity about the structure of the content.

I hope you find this post is useful. Read More

Cargo Emergency Shut Down System in Liquefied Gas Carrier

I am interested in designing ship-to-shore link and ESD arrangement in LNG vessel. I have involved in about three LNG projects, but I did not design or paid more attention in this field (because all the projects were front-end engineering design). In this post, I want to share you practical information about ESD arrangement as suggested by SIGTTO (Society of International Gas Tanker and Terminal Operators).

Function of Emergency Shut Down System

Function of cargo ESD system is to stop cargo liquid and vapor flow in the event of emergency and to bring the cargo handling system to safe condition. Read More

Little bets

Book Review: Little Bets, How Breakthrough Ideas Emerge from Small Discoveries

Weekend is almost over. So let’s begin new week with new insight. Instead of sharing chemical engineering things which may be quite serious, in this post I want to share you a book I read. The title is Little Bets – How Breakthrough Ideas Emerge from Small Discoveries by Peter Sims.

I just read second chapter of the book of ten chapters. So I am quite slow at reading. That is because content in second chapter is really amazing. I highlighted most of the chapter and I internalized the chapter. Problem I always face after reading good book is I forget the content or I don’t know how to behave better based on the book. So, here I write it so it will lessen my forgetfulness.

Title about second chapter is The Growth of Mind-SetI kept repeating word “growth”, “grow”, “growing” to myself and I visualized is as growing small tree. This chapter is really important for me. Read More

Methane number empirical models

Understanding Methane Number

In my previous LNG project, we need to supply gas with specified minimum methane number and specified higher heating value.

What is methane number?

It is the measure of resistance of fuel gases to engine knock, known as detonation. Detonation is produced by the auto-ignition of fuel/air mixture ahead of the propagating flame. Detonation must be immediately stopped to avoid increase of wear and tear and engine damage.

If MN is too low, the detonation can reduce engine efficiency and increases the quantity of harmful engine emissions.

MN Calculation

I searched if there is formula for the calculation, but I cannot find it. MN is not gas thermodynamic property, so no equation of state can be used to calculate it. I found there are several online methane number calculators. I tested three of them, Cummin, Wartsilla, and DNV MN calculator, respectively by using LNG Tangguh composition. These are the results.

Read More