Library / GUIDE FOR THE ESTABLISHMENT AND OPERATIONS OF DOWNSTREAM GAS FACILITIES IN NIGERIA (LPG, CNG, LNG) ISSUED BY

GUIDE FOR THE ESTABLISHMENT AND OPERATIONS OF DOWNSTREAM GAS FACILITIES IN NIGERIA (LPG, CNG, LNG) ISSUED BY

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Applicable to all Oil & Gas Operators
GUIDELINES FOR THE ESTABLISHMENT AND OPERATIONS OF CNG
COMPRESSION FACILITIES IN NIGERIA
Code: DPR Guide 0029 - 2020

Revision Date: 1st September 2020

13
vii.
Storage systems and vessels shall be fitted with over pressure protection devices
to release excess pressure under normal operating conditions and in emergency
situations.
viii.
Manually operated valves shall also be fitted to release pressure during
maintenance.
Note: All propane storage and handling facilities shall comply with Propane Rated
Standards.

3.4.1
Requirements for CNG Cascade tanks
In addition to the requirements for tanks listed in section 3.4, the following are applicable
to CNG tanks:
i. Each cylinder or bulk tank used for the storage of CNG shall be equipped with an
approved pressure relief device and isolation valve which shall be capable of
shutting off the pressure -relief device.
ii. Piping and gas storage systems shall be protected against over-pressure by safety
relief devices. Relief devices installed to protect the storage systems shall be such
that it limits the pressure to 120 per cent above the maximum allowable working
pressure of the system or the pressure which produces a loop stress of 75% of the
specified minimum yield strength, whichever is lower.
iii. A shut-off valve shall not be installed between the pressure relief valve and the gas
unit or bulk tank except that a shut-off valve may be used on multiple valve
installations where the arrangements of the valve will provide full required flow
through the safety relief devices at all times. The opening or connection between
the gas storage unit and safety relief device or devices shall have at least the
combined areas of all connected safety relief device inlets.