WHERE DOES LPG COME FROM?
Oct 16 - 22, 2006
LPG is a derivative of two large energy industries: natural gas processing and crude oil refining. When natural gas is drawn from the earth, it is a mixture of several gases and liquids. Methane, which is sold by gas utilities as "natural gas," constitutes about 90 percent of this mixture. Of the remaining 10 percent, 5 percent is propane and 5 percent is other gases such as butane and ethane. Before natural gas can be transported or used, the gases (which are slightly heavier than methane, the major component of natural gas) are separated out. Depending on the "wetness" of a producing gas field, gas liquids generally contain 1%-3% of the unprocessed gas stream. Some LPG is also trapped in crude oil. In order to stabilize the crude oil for pipeline or tanker distribution, these "associated" or "natural gases" are further processed into LPG. Worldwide, gas processing is a source of approximately 60% of LPG produced.
In crude oil refining, LPG is the first product produced on the way to making the heavier fuels such as diesel, jet fuel, fuel oil, and gasoline. Roughly 3% of a typical barrel of crude oil is refined into LPG, although as much as 40% of a barrel could be converted into LPG. Worldwide, crude oil refining is the source for the other roughly 40% of LPG supplies, although the ratio between gas processing and refining varies among regions.
LPG production from these sources is a natural derivative. That means production of LPG is assured since the primary motive for gas processors and refiners is to produce fuels other than LPG, and inevitably LPG is first produced. Although tied to the production of natural gas and crude oil, LPG has its own distinct marketing advantages and can perform nearly every fuel function of the primary fuels from which it is derived.
In Pakistan, there are many gas fields which are used to extract LPG.
USES OF LPG
The initial stage of switching from traditional fuels or kerosene to LPG in developing countries typically involves the use of a cylinder attached to a simple burner. As familiarity with LPG grows and incomes rise, the user may install a modern cooker inside the home, possibly with the gas supplied by rubber pipe from a cylinder placed outdoors or in a separate room. Later, hot water and/or a refrigeration system may be added. In remote rural communities, LPG can also be used to power electric generators, although diesel is generally a more economic option. Further, LPG can be used in conjunction with renewable technologies for decentralized power generation, to meet loads that may be beyond the capacity of the renewable system or as back-up fuel where intermittence may be a problem.
Internationally, LPG is being consumed as a fuel in the following sectors:
- Domestic (household) sector as cooking, heating and in nominal quantities as lighting fuel.
- Commercial sector such as cooking fuel in hotels and restaurants.
- Automotive sector as fuel for taxis, vans and private cars.
- Industrial sector as cutting and heating fuel.
- Agriculture sector for crop drying, etc.
- Other industrial uses such as manufacture of petrochemicals.
LPG AND CNG
LPG and CNG are all viable fuels with varying levels of infrastructure.
While LPG and CNG are both used in the automotive sector, there are considerable differences:
Average 70% lesser than petrol / diesel
Average 90% lesser than petrol / diesel
Reduces by about 20% as gas carburetors are often used
Same as petrol / diesel vehicles
Volume of Fuel tank
Large tanks avg. 6 times that of petrol / diesel for same mileage: additional weight and eats up boot space
One third that of CNG
Many times compared to petrol / diesel depending on quality of compressor
Same as petrol / diesel
Taxi / car: PKR 25,000
Taxi / Car: PKR 6,000 – 14,000
High pressure can be a safety concern
5-7 bar, comparable to conventional fuel.
Requires special equipment
Ease in handling as close to liquid fuels
Requires special equipment. A compressor alone costs PKR 20 million and a complete station could cost up to PKR 30 million
Average LPG stations cost PKR 3.5 million only.
Dependent on pipeline networks
Easily transported by road tankers like liquid fuels.
Dependent on pipeline networks
Supplies delivered by road tankers liquid fuels.
Longer lead time due to pipeline laying
Easy to develop, lead time of hardly three months for each facility
Initial investment in infrastructure
Average USD 250,000 and upwards for just a dispensing station with compressor of suitable capacity
Average USD 65,000
Over 9 million – 2 times more vehicles on road in cities across the world.