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Rollover in LNG Storage Tank

Rollover in LNG Storage Tank

Rifka Aisyah 5 Comments

I think reading BS EN 1160 makes my writing ideas grows. As a follow of of this post (LNG Basics: Understanding Its Typical Properties), I want to share you what I read and browsed about Rollover in LNG Storage Tank.

Rollover in one of physical phenomena explained in BS EN 1160, other than Rapid Phase Transition (RPT) and Boiling Liquid Expanding Vapor Explosion (BLEVE).

Rollover refer to process whereby large quantities of gas can be emitted from an LNG storage tank over a short period of time. How this could happen? Read More

Nitrogen vaporizing package

Nitrogen Gas Supply System

Rifka Aisyah 3 Comments

It is quite some time I don’t write about utility system. In this post I want to share you some basic knowledge of nitrogen supply system. In December 2015, I prepared several training presentation about nitrogen supply system when I was working in this company. I think it is a good idea to share some of them.

Nitrogen is used for purging activity and blanketing due to its unreacted feature.

Nitrogen is used at different application, depend on its application.

Required nitrogen purity based on its application

Required nitrogen purity based on its application

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Difference between Base Load, Peak Load, and Load Following Power Plant

Rifka Aisyah 1 Comment

Yesterday I had a discussion about our current project. The discussion was actually not only limited to that topic, however a topic in general: power plant. When one has plan to build a power plant, he must know operational profile of the power plant. Is it used for base load, peak load, or follower load ? What does it mean?

In this picture I show you the difference between those three. Read More

calculation holding time of LNG in storage tank

Predicting Holding Time of LNG in Storage Tank Without Venting

Rifka Aisyah Leave a comment

In this post, we use vacuum insulated type LNG storage tank when we don’t want to deal with boil-off gas handling. The storage tank have design pressure as high as 6-10 barg. When we store LNG in the LNG, boil-off gas will be generated due to heat leak to tank. Increasing temperature of LNG will increase total volume of LNG and vapor in the tank, thus increasing its pressure.

This phenomena leads to a simple question, “How long can LNG storage tank keep the vapor before PSV works?” Read More

LNG Basics: Understanding Its Typical Properties

Rifka Aisyah 2 Comments

For those who starts working with LNG, I recommend to read BS EN 1160 – Installations and equipment for liquefied natural gas – general characteristics of liquefied natural gas. The standard covers almost all LNG characteristics that you need to know, such as properties of LNG, evaporation of LNG, spillage, ignition, containment, and other physical phenomena. I think it will be nice to share some of them in this post.

There are three things at least you need to know about LNG before knowing other things.

lng-basic-properties
lng-basic-properties

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Understanding Flammability Limit and Explosive Limit

Rifka Aisyah 2 Comments

Have you heard about Flammability Limit and Explosive Limit? What does it mean? What the difference? These day I kept wondering if flammability limit and explosive limit is the same? Since I have to check vent stack data sheet from our mechanical engineer, I need to put low flammability limit criteria. What is that?

Explosion occur when three conditions are met:

  • Fuel
  • Oxygen (air)
  • Ignition source (spark or flame)

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Understanding Pumps Terminology

Rifka Aisyah 1 Comment

As a process engineer, I sometimes dealing with pumps. I usually feel confuse when I read pump specification or graphs offered by vendors. Here in this post, I want to share you some knowledge about pumps terminology that you may hear before what don’t really understand the meaning.

I create mind map for several most-often-used pump terminology that come to my mind. I’m sorry if the arrangement is a bit messy :D.

pump-terminology Read More

Reciprocating Pump P&ID Configuration

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Reciprocating pump is a class of positive displacement pump which includes piston pump, plunger pump, and diaphragm pump. It is often used where a relatively small quantity of liquid to be handled and where delivery pressure is quite large. Priming is not required because it is positive displacement pump. Reciprocating pumps have lower efficiency compared to centrifugal pump.

API 674 – Positive Displacement Pump – Reciprocating covers minimum requirements for reciprocating positive displacement pumps for refinery application. The standard also covers piping and instrumentation required for the pump. Read More