Written on December 1, 2009 at 3:50 pm, by Dr. Mahmood Moshfeghian
In this tip of the month (TOTM) we will describe the dense phase of a pure compound, what it is, and how it impacts processes. We will illustrate how thermophysical properties change in the dense phase as well as in the neighboring phases. The application of dense phase in the oil and gas industry willContinue Reading
Written on October 1, 2009 at 3:30 pm, by Dr. Mahmood Moshfeghian
In the August 2009 Tip of the Month (TOTM), it was shown that pumping power requirement varies as the crude oil °API changes. Increasing °API or line average temperature reduces the crude oil viscosity. The viscosity reduction caused higher Reynolds number, lower friction factor and in effect lowered pumping power requirements. Since the objective ofContinue Reading
Written on August 1, 2009 at 10:31 pm, by Dr. Mahmood Moshfeghian
During the life cycle of a crude oil pipeline the properties of transported oil change, because in gathering systems the produced oils come from different wells. New wells may be added or some wells may go out of production for maintenance and repair. Production rates during the life of wells vary, too. In addition theContinue Reading
Written on June 1, 2009 at 10:20 pm, by Alan Foster
Introduction To many people involved in the Oil and Gas production and refining industry, the terms monitoring and inspection are used interchangeably when referring to corrosion issues. However, this lack of differentiation can lead to misunderstandings and errors. It is our contention that a clear differentiation is needed and that engineers should strive to useContinue Reading
Written on May 1, 2009 at 10:07 pm, by Joe Honeywell
One of the most important physical properties of a gas is the ratio of specific heats. It is used in the design and evaluation of many processes. For compressors, it is used in the design of components and determination of the overall performance of the machine. Engineers are frequently asked to evaluate a compressor performanceContinue Reading
Written on March 1, 2009 at 9:23 pm, by Dr. Mahmood Moshfeghian
In the February 2007 tip of the month (TOTM), Joe Honeywell [1] presented a procedure for calculating fluid pressure drop for liquid in a piping system due to friction. Continuing Honeywell’s TOTM, we will outline procedures for calculation of friction losses in oil and gas pipelines. From an engineer’s point of view the question may arise “howContinue Reading
Written on January 1, 2009 at 9:13 pm, by Kindra Snow-McGregor
In this tip of the month, we will discuss how miscalculations and incorrect analysis of potential process upsets can affect process safety. There are many aspects in facility design engineering and process safety engineering that should be considered when designing a new facility or debottlenecking an existing one. During these times of compressed schedules andContinue Reading
Written on October 1, 2008 at 8:25 pm, by Dr. Mahmood Moshfeghian
Gas density estimates are of fundamental importance for process simulation, equipment design, and process safety engineering. In the previous Tip of the Month (TOTM), two shortcut methods for predicting sour and acid gas density were evaluated. We showed that Katz correlation gives accurate results for lean sweet gases and it is the most accurate inContinue Reading
Written on September 1, 2008 at 8:10 pm, by Dr. Mahmood Moshfeghian
Gas density is needed for process simulation and equipment design. For example, accurate predictions of gas density are needed for calculation of pressure drop in piping/pipeline and for vessel sizing. Accurate gas density is also essential for custody transfer metering. Gas density, , is calculated by: (1) Where: &Gas density, kg/m3 (lbm/ft3) Absolute temperature, KContinue Reading
Written on March 1, 2006 at 10:53 am, by Dr. Mahmood Moshfeghian
The best way to prevent hydrate formation (and corrosion) is to keep the pipelines, tubing and equipment dry of liquid water. There are occasions, rightly or wrongly, when the decision is made to operate a line or process containing liquid water. If this decision is made, and the process temperature is below the hydrate point,Continue Reading
