Storage of LPG

Most liquid feedstock and chemicals such as naphtha or benzene are stored in above ground steel tanks. In order to prevent the formation of explosive mixtures in the tank ullage, some organisations use floating roof tanks, particularly favoured for large tanks in the refining industry, whereas others use inert gas blanket of nitrogen, particularly favoured for small tanks in the chemicals industry. 

The main concern is the storage of liquefied petroleum gas (LPG) which in this context can be propane and butane feedstock or product, or ethylene and propylene. The storage of LPG is costly and there are various technologies which depend on the amount of material to be stored. 

LPG has been the main source of fuel for some of the petrochemical industries worst fires and explosions. As a consequence the safety measures and regulations concerning LPG storage are extensive and a full discussion of these is beyond the scope of this work. 

Small volumes of LPG are stored in large cylindrical tanks often referred to as bullets, with typical volumes 100cm. 

Because of a major fire and explosion at Feyzin, France 1966 there are extensive regulations concerning the construction and operation of such pressure spheres. The following are some of the general issues to be considered. 

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The general requirements for the storage of LPG eylinders are given in Tables 9.16 to 9.18. Considerations in the transport of eylinders by road are given in Chapter 15. 

Table 9.17 Recommended minimum separation distances for total storage of LPG in cylinders stack (the greater of the two distances is advised) or size of maximum...

Schulz-Forberg, B., B. Droste, and H. Charlett. 1984. Failure mechanics of propane tanks under thermal stresses including fire engulfment. Proc. Int. Symp. on Transport and Storage of LPG and LNG. 1 295-305. 

Liquefied petroleum gas Storage of LPG at Fixed Installations (HSE, HSG 34) Storage and Use of LPG at Metered Estates (HSE, CS11) Storage and Use of LPG on Construction Sites (HSE, CS6) Keeping of LPG in Cylinders and Similar Containers (HSE, CS4)... 

The Storage of LPG at Fixed Installations, Health and Safety Executive (UK), 1987... 

Outline the requirements for the safe storage of LPG cyiinders on a construction site. 

Every occasion where LPG is carried in motor vehicles Storage on site of more than five full cylinders Use of LPG in confined spaces Storage of LPG inside buildings or structures... 

Workers must not be smoking or be near any open flames when handling tanks. Any area near the use or storage of LPG must be designated as a nonsmoking area. Post appropriate signs and properly instruct all employees. 

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