Wet gas measurement is becoming widely used in the modern oil and gas market place. The effect of entrained liquid in gas and its impact on measurement systems is being researched world-wide by various laboratories and JIP working groups. The impact can be very significant financially. Hydrocarbon Dew Point can also effect the financial operation of a gas transportation company if not managed effectively amounting to hundreds of thousands of dollars per annum based on incorrect sampling and its subsequent analysis.
The subject is quite large and encompasses many different concepts, meter types, standards and opinions, with many new ideas brought to the forefront each year as more research is done. From upstream applications to midstream measurement issues caused by liquid drop out in the pipelines were gas gathering systems are used.
The issue of liquid entrained gas is becoming a big issue! Small quantities of hydrocarbon liquid in a gas sample stream can have a large impact on the BTU value analysis and cause large losses or gains depending on which side of the financial fence you are.
This paper will describe the phenomenon of wet gas, liquid drop out and some of the various types of measurement concepts that are and may be used for these types of measurement, together with some recent thinking and concepts associated with wet gas measurement.
The paper will mention some of the terms and mathematical concepts used to enable the reader to grasp a better understanding of what this stuff is about together with some information on wet gas impact in the high gas volume fraction (GVF) applications and sample collection.
The paper is divided into sections and will discuss the various levels of wet gas, dew point and liquid ratios in natural gas.
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the measurement objectives derived from a wet gas methods are:
Reservoir and well management,
Production (gas, condensate and water) allocation
Formation water breakthrough detection,
Flow assurance, e.g. hydrates, scale, salt deposition
Effective Sampling and the Financial effect on Mid-Stream transportation systems. Dew Point and its Effect on Hydrocarbon Measurement.