Pipelining Liquefied Petroleum Gas (LPG)

Liquefied Petroleum Gas (LPG) is a mixture of light hydrocarbons, gaseous at normal temperature (15°C) and pressure (101.329 kPa) and maintained in the liquid state by increased pressure or lowered temperature. LPG is the generic name for “commercial butane” and “commercial propane”. Because of its high heating values, high purity, cleanness of combustion and easy of handling, LPG finds very wide application in a large variety of industrial, commercial, domestic and leisure uses. The history of LPG goes back to the early 1900s. The first car powered by propane ran in 1913 and by 1915 propane was used in torches to cut through metal. Current global LPG consumption is over 200 million tonnes/annum. Transportation of LPG by pipelines is environmentally friendly in that it entails less energy consumption and exhaust emissions than other modes of transportation. Worldwide, there are over 220,000 miles (350,000 kilometers) of petroleum, refined products and LPG pipelines. The majority are in the United States. Some refined products pipelines carry LPG in batch form. However, there are only about 8000 kilometers of single phase pipelines, of various diameters, that transport LPG (propane or butane) fluids (Mohitpour et al, 2006). There are a number of codes that industry follows for the design, fabrication, construction and operation of LPG facilities. However, there are no regulations or legislation that specifically cite the pipeline transportation of the product. From a safety point of view, although LPG is non-toxic, it can be very dangerous if not handled properly. A partial or complete rupture of an LPG pipeline, resulting in an accidental release, will cause issues related to evaporation, vapor cloud propagation and dispersion. Response to emergencies such as rupture and leak in LPG pipelining is thus critical and must ensure rapid action with respect to containment, control, elimination and effective maintenance/repair. This paper provides an overview the code and regulatory requirements and summarizes the more significant aspects of the design, construction and safe operation pertaining to LPG pipeline systems. It covers the timeline and statistics of the global LPG business; the type of facilities that make up the industry; and the LPG properties pertinent to pipeline design. It also addresses the significant safety issues of LPG pipelining including a discussion on emergency response and associated equipment needs and repair techniques.