In this post, I want to share to you how to estimate total capital cost of flare system, especially installation cost. In previous post, I already shared a step-by-step method on how to estimate purchase equipment cost of flare system.
Installation cost of flare system covers direct installation costs and indirect installation costs.
In this post I want to share how to estimate total capital cost of flare system. Since the post is quite long, I will divide it into 3 posts:
In the last part, I will also post a free spreadsheet on how to estimate capital cost of flare system described in every post.
For disclaimer, the accuracy of this cost estimation is ±30% (study estimate). Apply for tip flare tip diameter ranging from 1-60 in and stack heights ranging from 30-500 ft. Standard construction material is carbon steel.
The cost is based on 2017$ basis.
In this post I want to share how to estimate gas specific gravity.
Gas specific gravity refers to the ratio between the density of a gas and the density of air at standard conditions (1 atm pressure and 60°F). When assuming ideal gas law behaviour, it equals the molecular weight of the gas divided by that of air.
Gas specific gravity data is frequently utilized in chemical engineering design processes. For example, gas specific gravity data is used to:
In this post I want to share to you how to estimate wind speed as function of height. Wind velocity plays a significant role in influencing the dispersion of released fluids. Wind speed rises with altitude above the earth’s surface, so reference height should be specified. Typically, 10 m is used as the meteorological standard unless noted otherwise.
Wind speed is also a function of weather stability and on the terrain.
Weather stability relates to vertical temperature gradients and atmospheric turbulence. The Pasquill-Gifford (P-G) classes are commonly used, with class G excluded from dispersion modelling. Read More
I plan to post more about process safety fundamentals in the future. In this post I want to share about process safety fundamentals which is important terms regarding characterization of fires and explosion.
Disclaimer: I am not a process safety expert. I am still learning about process safety topics. So, your feedback is appreciated.
Based on statistics, the main cause of accidents in the chemical industry is fires and explosions. To prevent fires and explosions, we need to:
Understanding the basics of fires and explosions begins with familiarizing yourself with key terms related to these phenomena. You will learn through this post. Read More
In this post I want to share to you about closed drain systems and how to design them. You may know several types of drainage in process plant, which are:
This post will cover about closed drain system. Hopefully in the near future I share to you other types of drain.
During maintenance activities, process liquid in the equipment should be emptied. The liquid must be collected. The volume of collected liquid can be significant, therefore must be recovered and can be reused in the process or disposed safely.
Closed drain system is facility used to collect the liquid from the bottom of vessels and their associated piping to a recovery vessel or closed drain drum or closed drain vessel. The liquid flows to the vessel or drum by gravity. Read More
In this post I want to share several examples of fail-safe position selection of control valves. I posted about this topic a long time ago. You can also check the post.
A control valve consists of valve body, trim, or stem, plug and seat, and an actuator. The valve body consists of an orifice through which the manipulated variable passes. The trim or stem is connected to the diaphragm and the valve plug that can be in the form of a ball, a disk, or a gate. The valve seat offers a tight seal for a valve shutoff position.
In this post, I want to share to you how to easily estimate the time needed for the vessel to collapse. The equation involves several simple and basic equation, such as conservation principle and adiabatic compression equation. Let’s dig into the example.
There is a thermally insulated vessel initially at atmospheric pressure and partially filled with water. The vessel is fed with additional water at a constant flow rate of 2 m3/h. The air contained in the vessel headspace is compressed as the additional water is fed. The vessel can withstand a maximum pressure of 3 atm absolute. Read More
In this post, I want to share with you the applications of globe valves and their examples. Different from ball, plug, and gate valves, which are used to start and stop fluid flow in piping systems, globe valves are used to regulate flow. Globe valves usually should not be used for less than 20% opening for throttling, because it will increase the wear and load concentration on the seat and plug.
Typical application of globe valves is for control valves bypass. When control valve is taken out for maintenance purpose, a bypass globe valve provides continuous operation with some level of regulation. Read More
In this post I want to share with you the applications of butterfly valves and their examples. A butterfly valve can stop, regulate, and start the fluid flow. Due to its ninety-degree rotation of the handle and the disk, the valve is quickly and easily operated.
Butterfly valves offer many advantages over ball, gate, globe, and plug valves, such as lower cost, less weight, less space requirements, and lower maintenance cost. The maintenance cost is relatively low because of few moving parts.
Butterfly valves are usually selected for utility services and low pressure gas services, with pressure class 300 and lower.
