Relevant • Independent • Objecve rupture near a pumping staon in Illinois when two drag racers crashed through a chain-link fence and connued more than 100 feet to hit the above- ground pipeline. 3 A third alternave has been proposed by Alexander Bolonkin, 4 based on the buoyancy of natural gas. He envisions a trunk natural gas pipeline that would be tethered rather like a helium-filled balloon, not elevated or buried. Methane, the chief constuent of natural gas, has half of the molecular weight of oxygen, so the buoyancy would disappear as pressure approaches two atmospheres. Pressure in convenonal natural gas pipelines oſten exceeds 200 atmospheres, so a tethered pipeline would have to be of much larger diameter to preserve buoyancy. (Bolonkin proposes to keep pipeline pressure below 1.5 atmospheres.) In order to keep the pipeline buoyant, he also proposes replacing the convenonal metal or plasc pipeline material with a double layer of lightweight flexible thin film. He illustrates the concept with a pipeline design that calls for a diameter of 10 metres, with the bulk of the pipeline elevated 90 metres above the land surface. Bolonkin claims that such a pipeline would be orders of magnitude cheaper to construct than a buried pipeline, and would require less energy to operate. Among the other advantages, he cites the following: Much lower environmental impact as clearance of an enre right-of-way would be unnecessary, and river crossings would not require trenching or direconal drilling Possible shortening of construcon me from years to months Reduced interference with enjoyment of surface rights Ease of repair Reduced exposure to theſt and terrorism June-July 2012 CERI Commodity Report — Natural Gas Why Bury Pipelines? By Thorn Walden The vast majority of energy and water pipelines are buried, generally to a depth of 1-2 metres. One notable excepon is the Trans-Alaska Pipeline System (TAPS), much of which is elevated to avoid melng permafrost. (A small secon is buried and refrigerated, again to avoid melng permafrost.) Various pipelines have small secons that protrude above ground level. Another is the Tas-Tumas/ Yakutsk natural gas pipeline in Siberia, also traversing permafrost. Most of it is above ground on untreated mber H-supports or within a berm. 1 The TAPS oil pipeline is elevated sufficiently to enable large animals to pass beneath at various crossing points. 2 Even so, it has been observed that mosquito-harassed caribou tend to balk at crossing beneath. Animals apparently prefer a ramp to enable them to cross over rather than under a pipeline. The comparave risks to pipeline integrity are not straighorward. One might think that exposure to the elements would be a disadvantage to above- ground pipelines. Third-party damage to buried pipelines from construcon equipment is one of the more common causes of ruptures to buried pipeline, although above-ground pipelines are not immune to third-party damage. Enbridge recently suffered a CERI Commodity Report – Natural Gas Editor-in-Chief: Mellisa Mei ([email protected]) Contents Featured Arcle ...................................................................... 1 Natural Gas Prices .................................................................. 4 Weather ................................................................................. 6 Consumpon and Producon ................................................. 8 Transportaon........................................................................ 10 Storage ................................................................................... 12 Liquefied Natural Gas ............................................................. 15 Drilling Acvity ....................................................................... 17
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Relevant • Independent • Objective
rupture near a pumping station in Illinois when two drag racers crashed through a chain-link fence and continued more than 100 feet to hit the above-ground pipeline.3
A third alternative has been proposed by Alexander Bolonkin,4 based on the buoyancy of natural gas. He envisions a trunk natural gas pipeline that would be tethered rather like a helium-filled balloon, not elevated or buried. Methane, the chief constituent of natural gas, has half of the molecular weight of oxygen, so the buoyancy would disappear as pressure approaches two atmospheres. Pressure in conventional natural gas pipelines often exceeds 200 atmospheres, so a tethered pipeline would have to be of much larger diameter to preserve buoyancy. (Bolonkin proposes to keep pipeline pressure below 1.5 atmospheres.) In order to keep the pipeline buoyant, he also proposes replacing the conventional metal or plastic pipeline material with a double layer of lightweight flexible thin film. He illustrates the concept with a pipeline design that calls for a diameter of 10 metres, with the bulk of the pipeline elevated 90 metres above the land surface. Bolonkin claims that such a pipeline would be orders of magnitude cheaper to construct than a buried pipeline, and would require less energy to operate. Among the other advantages, he cites the following: Much lower environmental impact as clearance
of an entire right-of-way would be unnecessary, and river crossings would not require trenching or directional drilling
Possible shortening of construction time from years to months
Reduced interference with enjoyment of surface rights
Ease of repair Reduced exposure to theft and terrorism
June-July 2012
CERI Commodity Report — Natural Gas
Why Bury Pipelines? By Thorn Walden The vast majority of energy and water pipelines are buried, generally to a depth of 1-2 metres. One notable exception is the Trans-Alaska Pipeline System (TAPS), much of which is elevated to avoid melting permafrost. (A small section is buried and refrigerated, again to avoid melting permafrost.) Various pipelines have small sections that protrude above ground level. Another is the Tas-Tumas/Yakutsk natural gas pipeline in Siberia, also traversing permafrost. Most of it is above ground on untreated timber H-supports or within a berm.1
The TAPS oil pipeline is elevated sufficiently to enable large animals to pass beneath at various crossing points.2 Even so, it has been observed that mosquito-harassed caribou tend to balk at crossing beneath. Animals apparently prefer a ramp to enable them to cross over rather than under a pipeline. The comparative risks to pipeline integrity are not straightforward. One might think that exposure to the elements would be a disadvantage to above-ground pipelines. Third-party damage to buried pipelines from construction equipment is one of the more common causes of ruptures to buried pipeline, although above-ground pipelines are not immune to third-party damage. Enbridge recently suffered a
CERI Commodity Report – Natural Gas Editor-in-Chief: Mellisa Mei ([email protected]) Contents Featured Article ...................................................................... 1 Natural Gas Prices .................................................................. 4 Weather ................................................................................. 6 Consumption and Production ................................................. 8 Transportation........................................................................ 10 Storage ................................................................................... 12 Liquefied Natural Gas ............................................................. 15 Drilling Activity ....................................................................... 17
CERI Commodity Report - Natural Gas
Page 2
Although natural gas is the most obvious commodity to transport in this fashion, Bolonkin also claims that it can be used to transport heavier-than-air commodities, using what he calls a wing container, that employs a very light monorail. Rather than construct a canal from the Red Sea to the Dead Sea to prevent the water levels in the latter from continuing to fall, he proposes to cover 90 percent of the Dead Sea surface with plastic, and to transport water from the Red Sea by means of a 30-metre tethered pipeline at an estimated one twenty-fifth of the capital cost of the proposed canal. Endnotes 1McFadden, T. T. and F. L. Bennett, Construction in Cold Regions: A Guide for Planners, Engineers, Contractors and Managers, Wiley, 1991, p. 359. 2Truett, J. C. and S.R. Johnson, The Natural History of an Arctic Oil Field: Development and the Biota, Academic Press, 2000, p. 100. 3“Two Cars in Fiery Pipeline Crash were Drag-Racing, Police Say,” Chicago Tribune, March 6, 2012. 4Bolonkin, A. A., “A Cheap Levitating Gas/Load Pipeline”, accessed at arxiv.org/ftp/arxiv/papers/0812.0588.pdf.