1.0.1 This code was formulated in order to implement the relevant principles and policies of the state, unify the technical requirements, conserve energy and resources, protect environment and achieve safety and usability, advanced technology and economic rationality in the design of underground oil storage in rock caverns.
1.0.2 This code applies to the engineering design of the underground oil storage in rock caverns for storing such storable crude oil, gasoline and diesel fuel.
This code does not apply to the engineering design of steel tank off/on wall in manual caverns, petroleum storage in natural caverns and storage in salt caverns.
1.0.3 In addition to this code, the design of underground oil storage in rock caverns still shall comply with those specified in the current relevant standards of the state.
2 Terms
2.0.1 Underground oil storage in rock caverns
It refers to the underground space system excavated in the rock mass under a steady underground water level to store crude oil, gasoline and diesel fuel. It is named as "water-sealed storage" for short.
2.0.2 Cavern
The underground space excavated in rock mass to store crude oil and its products
2.0.3 Caverns tank
Caverns tank is composed of one or several mutually connected caverns, and its functions are equivalent to one oil tank on ground.
2.0.4 Connecting tunnel
The channels connecting the caverns in order to guarantee the circulation of stored crude oil and its product between caverns and to keep one same liquid level
2.0.5 Access tunnel
The channel leading from the ground to the cavern for the construction and tunneling of cavern and meeting the requirements of equipment passing, tapping, ventilation, water supply and drainage, power supply and human passing during the construction period
2.0.6 Shaft
Shaft built from the top of cavern to the ground or operation tunnel
2.0.7 Shaft operation area
The area surrounding the shaft opening, used for the maintenance, operation and management of oil pump, water pump, instruments and electricity
2.0.8 Water curtain hole
A hole drilled for artificial water flooding in order to keep the underground water sealing condition
2.0.9 Water curtain tunnel
The tunnel used for construction of water curtain hole, which can store water during operation and feed water through the water curtain hole
2.0.10 Concrete plug
The reinforced concrete structure installed in access tunnel or shaft to plug the caverns tank
2.0.11 Pump pit
The pit at the cavern bottom facing to the shaft to mount the submersible oil and water pumps and instruments
2.0.12 Water bed
A water layer set with a certain height at the cavern bottom to, used to deposit the impurities in the crude oil and its products and to collect the leakage water from surrounding rock
2.0.13 Logging hole
A hole used to monitor the underground water level and water quality
2.0.14 Operation tunnel
The tunnel leading from the ground to each shaft operation area
2.0.15 Storage perimeter
The border line of construction protective area, used to structure stability of the underground oil storage in rock caverns
2.0.16 Hydrogeological perimeter
The border line of hydraulic protective area required to keep the steady design underground water level of the underground oil storage in rock caverns
2.0.17 Vapor recovery unit
The unit used to recovering the oil gas exhausted from the underground caverns tank
3 General Requirements
3.0.1 The design storage capacity of the underground storage in caverns for storing crude oil should not be less than 1,000,000m3, and that of those for storing refined oils should not be less than 500,000m3.
3.0.2 The fire hazard classification of oil products stored in underground storages in caverns shall be in accordance with those specified in Table 3.0.2.
