Page 17 - Petroleum and Gas Field Processing

combusted, it produces sulfur oxides, which are a nuisance to
consumers. Both H 2 S and CO 2 are corrosive, especially in the
presence of water. Once removed, H 2 S could be commercially
utilized to produce sulfur.
3. Heavy hydrocarbon separation: It is desirable to remove hydro-
carbons heavier than methane from natural gas, especially for fuel
gasses. Heavier hydrocarbons, specifically C þ tend to condense,
3
forming two-phase flow and thus creating pipeline operating
problems.
Irrespective of the source of natural gas, the final specifications set for
market sales requirements are usually the following [1]:

H 2 S 0.25–0.3 grain per 100ft 3
(one grain ¼ 64.799 mg)
Total sulfur 20 grains per 100 ft 3
Oxygen (air) 0.2% by volume
Carbon dioxide 2% by volume
Liquefiable hydrocarbons 0.2 gal per 1000 ft 3
Water content 7 lbs/MMSCF (in a 1000-psia gas line)
Thermal heating value 1150 Btu/ft 3

Identification of the hydrocarbon constituents of crude oils and
associated natural gas along with their corresponding commercial products
are summarized in Table 1 [1].

REFERENCE

1. Abdel-Aal, H.K. Surface Petroleum Operations, Saudi Publishing & Distributing
House, Jeddah, 1998.

Copyright 2003 by Marcel Dekker, Inc. All Rights Reserved.