The need for good quality measurement has increased dramatically in recent years. Deregulation of market pricing structures, open access markets, increased exploration and drilling costs, fierce competition and new regulatory requirements have all influenced today’s approach to quality measurement methodologies. In fact, the terminology has evolved from “gas volume measurement” to “total energy measurement.” Today, not only is the volume of gas a consideration, but also the quantity of energy the gas produces. The gas industry has evolved from the MMcf to the MMBtu.
In Part One (P&GJ July 2012) we discussed the practice of natural gas sampling, challenges, current standards and the basic equipment that is available for the measurement technician.
Natural gas is one of the most important energy resources1. However, its chemical composition can fluctuate considerably, depending on where it is found. Added to this, the various gas qualities are mixed together due to the networked pipeline system of main and sub branches, receiving and transfer stations and gas storage facilities. This means that the natural gas must be tested qualitatively and quantitatively at strategic points to establish its volume and its quality parameters such as its calorific value (CV or Btu), hydrocarbon dew point and hydrogen sulfide content.
Gas chromatographs (GCs) are installed all over natural gas pipeline networks, providing an analysis of the flowing gas and calculating the physical properties used for the flow calculations and for custody transfer. However, a clear understanding of just how the GC works and the considerations that need to be made for the installation and operation of the GC are often lacking in the industry. This article discusses the major components of the GC and provides an understanding of the theory and practice of gas chromatography in the pipeline industry.
When it comes to gas measurement, the technology is as varied as the multitude of challenges that face this important sector of the utility industry. Winston C. Meyer is a well-known gas measurement guru who plies his trade with CenterPoint Energy in Houston. Because his job involves integrating technology and bringing advancements to gas measurement, Meyer has been active with manufacturers and industry associactions for more than 30 years. He is now focused on electronic instrumentation for gas supply needs, loss and unaccounted-for reporting efforts, technician training, automated meter reading and resource management.
A new instrument called realSens™ has been designed by Synodon Inc. for the remote sensing detection of leaked natural gas.
There are several types of flow meters used to measure the flow profile of a fluid. They are; turbine flow meters, ultrasonic flow meters, magnetic flow meters, Coriolis flow meters and target flow meters.
The flow measurement performance of two commercially available ultrasonic flow meters has been evaluated under conditions in which there were various levels of contaminate-like coating applied to the inside wall of the pipe upstream of the meter.
Ultrasonic flow meters are among the most popular of the flow meter types. They are used for a wide range of applications, including natural gas and petroleum liquids custody transfer, check metering and flare gas measurement.
Custody transfer measurement in the oil and gas business has been described many ways. It has been called an accuracy in measurement that both the buyer and seller can agree upon and it has been called the best that can be achieved to meet the contract conditions.
Well-known throughout the flow measurement industry, Jesse Yoder is founder and CEO of Flow Research, Wakefield, MA. Since 2000, he has focused principally on world markets for flow, pressure and temperature devices as they are employed in the energy business. He excels in his chosen pursuit by the force of his intelligence, his enthusiasm and his research and writing aptitude.
Dresser Masoneilan along with joint venture partner DS Control Technologies in Novgorod, Russia, say they have demonstrated a new benchmark in large-valve positioner accuracy.