Page 63 - Handbook of Natural Gas Transmission and Processing Principles and Practices

1.12. Sales Gas Transmission
After the raw gas has been processed to meet pipeline gas specifications, the marketable (sales) gas
is transported through pipelines to industrial and residential consumers or to underground storage
facilities for later delivery to these consumers as demand dictates. A number of compressor stations
(containing one or more compressor units) are located along the pipeline system to maintain the
pipeline pressure and overcome the pressure drop in the pipeline. Sales gas transmission will be
discussed in detail in Chapter 15.
When the sales gas reaches a local gas utility, it normally passes through a gate station to serve
three purposes: (1) reducing the pressure in the line from transmission levels to distribution levels,
(2) adding an odorant so that consumers can smell even small quantities of gas, and (3) measuring
the flow rate of the gas to determine the amount delivered to the utility. From the gate station, sales
gas then moves into distribution lines to supply gas to the end users/customers.

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