Abstract
Owing to the limited accuracy and measurement uncertainty of the instruments installed in gas pipeline systems, it is impossible to completely avoid transmission loss during transportation of natural gas. This study established an uncertainty model for the measurement system determining the complex flow rates of trunk gas pipelines, analyzed the uncertainty calculation methods of different metering systems, and developed a calculation method for determining the theoretical transmission loss. Application showed that the theoretical transmission loss serves not only as an early warning regarding a transmission loss, but also as a guide to the pipeline enterprise for determining the transmission loss assessment index. If the actual transmission loss rate is smaller than the theoretical transmission loss rate during the calculation cycle, it means that the pipeline metering system is working normally. Otherwise, it is necessary to immediately investigate the reason behind the transmission loss and implement corresponding measures.
Highlights
A generic definition of transmission loss of gas is the difference between metered gas receipts and metered gas deliveries to end-use customers; in other words, the volumetric difference between the gas injected into a pipeline system and the gas measured at customers’ meters.[1]
We analyzed the uncertainty calculation methods of different metering systems based on the error theory and obtained the measurement uncertainty of the inlet and outlet ends of a trunk gas pipeline; a calculation method for determining the theoretical transmission loss was developed and the influencing factors were analyzed
To analyze the theoretical transmission loss in the whole trunk gas pipeline system, suppose that the measurement instruments in the branch measuring system are independent of each other and the pipeline operation parameters are measured independently by the related instruments, and the theoretical transmission loss can be obtained by the following three steps: the first step is to determine the combined uncertainty of a single measuring system; the second step is to calculate the combined uncertainty of the parallel flow measuring system; and the third step is to obtain the combined uncertainty of the inlet and outlet ends
Summary
A generic definition of transmission loss of gas is the difference between metered gas receipts and metered gas deliveries to end-use customers; in other words, the volumetric difference between the gas injected into a pipeline system and the gas measured at customers’ meters.[1]. We analyzed the uncertainty calculation methods of different metering systems based on the error theory and obtained the measurement uncertainty of the inlet and outlet ends of a trunk gas pipeline; a calculation method for determining the theoretical transmission loss was developed and the influencing factors were analyzed. To analyze the theoretical transmission loss in the whole trunk gas pipeline system, suppose that the measurement instruments in the branch measuring system are independent of each other and the pipeline operation parameters are measured independently by the related instruments, and the theoretical transmission loss can be obtained by the following three steps: the first step is to determine the combined uncertainty of a single measuring system; the second step is to calculate the combined uncertainty of the parallel flow measuring system; and the third step is to obtain the combined uncertainty of the inlet and outlet ends. In order to be distinguished from the total rate Q, the flow rate here is represented by lowercase q qn
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call