From foremost physics at CERN to the development of technologies, gases are intrinsically involved in the research sector, as Tony Wheatley explains.
The gas phase of matter has always held a fascination that the other more tangible phases lack, in that it is usually invisible and unless contained, quickly dissipates and is ‘gone’.
The chemical and physical properties of gases are exploited in a broad range of different fields and the industry supplying these gases has developed techniques of purification, blending, packaging, storage and distribution to cater for many diverse requirements.
In addition to these indispensible services in support of research activities worldwide, industrial gas suppliers are at the core of several high profile research projects, three of which are featured in this article.
Gases for Research Laboratories
A broad range of high quality Custom Calibration Gas Standards for use in laboratory, R&D and industrial analysis applications.
Industrial Health and Hygene Calibration Gas Standards for many market segments including; laboratory, university, petrochemical, research, energy, computer science and process management.
A variety of Petrochemical and Refinery Calibration Gas Standards in both the liquid phase and gas phase.
Environmental Gas Standards including EPA Protocol Gas used to ensure environmental safety, compliance and meet regulatory requirements.
Calibration gases for BTU (energy value) analysis by gas chromatography and Residual Gas Analysis using mass spectrometry.
Instrument grade pure gases to preserve the integrity of instrument columns and detectors.
High Purity Oxygen at 30% lower cost
Oxygen is the 3rd largest bulk chemical produced in the US, but at lower cost this market would grow significantly larger, driven by demand from power generation, pollution control and many other industrial processes including the production of steel, glass, paper and aluminium.
Oxygen-enriched combustion could increase the efficiency of high-temperature furnaces and minimise the formation of nitrogen oxide pollutants, a major contributor to smog and ground-level ozone.
Oxygen is already being used in a new generation of power plants that rely on coal gasification and could also be used to improve the economics and environmental performance of more traditional coal-burning power generation.
Atmospheric gases oxygen, nitrogen and argon are produced commercially by separating air using a variety of technologies for over 100 years.
Typically cryogenic distillation is used for large tonnage production (100–2000 tpd) of high purity (> 95%) oxygen, Pressure or Vacuum Swing Adsorption (PSA / VSA) for small-tonnage production (less than 100 tpd) and other techniques exist for smaller production capacities.
Large scale cryogenic air separation units are both capital and energy intensive because massive refrigeration capacity is required to cool air to its liquefaction temperature of about -170°C.
As early as 1989 Air Products and chemicals, Inc (APCI) started pursuing a unique method of separating oxygen using an Ion-Transport Membrane (ITM) developed by Ceramatec, Inc.
The Advanced Technology Programme awarded Air Products cost-shared funding in 1993 worth $2m for a three year project, but a functional ITM prototype was not achieved in this timeframe.
Partnered with several businesses, APCI is still committed to its original objective to develop an oxygen-separation technology that will generate high-purity (> 95%) oxygen with a 30% cost saving over traditional processes and has agreed to a jointly funded project with the Department of Energy (DOE).
In October 1998, US Energy Secretary Bill Richardson announced a new $24.8m research project to explore an entirely different and possibly revolutionary way to produce high-purity oxygen, one of the most commonly used commodities in modern industry.
Vision 21 Programme
In the DOE’s ‘Vision 21’ programme, low-cost oxygen separation has been targeted as one of the key research goals for the next decade in conjunction with the gas-to-liquids research programme.
Gas separation membranes are envisioned as a way to provide high-quality oxygen to react with natural gas for generating electric power, to react in coal or biomass gasifiers to form a ‘synthesis gas’, that can be further processed into transportation-grade fuels or chemicals.
A hybrid system showing great promise is integration of gasification with a fuel cell. Fuel cells offer very high efficiencies, with emerging fuel cells having 60% efficiency.
These emerging fuel cells also produce very high-temperature exhaust gases that can either be used directly in combined-cycle or used to drive a gas turbine.
Integrated gasification fuel cell hybrids have the potential to achieve up to 60% efficiency and near-zero emissions. Moreover, the concentration of carbon dioxide lends itself to removal by separation or other capture means.
Such systems require that the syngas derived from gasification be free of contaminates for use in the fuel cell, or that the hydrogen be separated from the syngas (hydrogen is the fuel element for the fuel cell).
Carbon sequestration is the ultimate solution to stabilising global carbon emissions. A prerequisite to carbon sequestration is carbon capture, which for power systems is carbon dioxide capture.
Power system developments are moving toward higher efficiency to lower carbon dioxide emissions on a per-Btu basis and toward more concentrated carbon dioxide emission streams through oxygen, rather than air-based gasification and combustion.
Air separation efforts support the move to oxygen-based systems. Ultimately, carbon dioxide must be captured either through chemical or physical separation methods.
Vision 21 is addressing the challenges outlined above through a cooperative effort involving industry, universities, and National Laboratories. It includes fundamental research in materials science, novel concept evaluation at bench-scale, and process verification at pilot-scale.
Facilities such as the Power System Development Facility at Wilsonville, Alabama, along with industry/National Laboratory/university facilities, are being enlisted to address these challenges.
CERN announces start-up date for Large Hadron Collider (LHC)
CERN (Conseil Européen pour la Recherché Nucléaire), or the European Organisation for Nuclear Research, announced that the first attempt to circulate a beam in the Large Hadron Collider (LHC) would be made on 10th September 2008.
The news came as the cool down phase of commissioning CERN’s new particle accelerator reached a successful conclusion. The LHC is the world’s most powerful particle accelerator, producing beams seven times more energetic than any previous machine and around 30 times more intense when it reaches design performance, probably by 2010.
Housed in a 27km tunnel, it relies on technologies that would not have been possible 30 years ago.
The CERN Control Centre, from where the LHC will be operated
The superconducting magnets have been specially developed for the LHC operating at minus 271.3 degrees Celsius, closer to absolute zero than the temperature in outer space – making the LHC the coldest place in the universe.
The LHC needs 120 metric tons of liquid helium to cool down the accelerator to a mere 2.17 Kelvin, when helium becomes a superfluid and an ideal thermal conductor (90 metric tons are being used in the magnets and the rest in the pipes and refrigerator), and 40 more metric tons to cool down the magnets of the large detectors to 4.5 Kelvin, so that the coils are superconducting.
Helium will also cool down the large spectrometer magnets for particle physics experiments. But even this huge amount of helium is just about 5% of the annual US consumption of helium for cryogenics!
In the period up to 2011, industrial gas specialist Messer will supply around 160,000kg of helium through its Swiss subsidiary, Lenzburg-based Messer Schweiz AG.
Messer transports the helium from Orenburg to its European filling plants in its own vacuum-insulated tank containers with a capacity of 40,000 litres. The Messer Group’s Austrian site is home to Europe’s largest helium tank farm with capacity to store liquid helium during maintenance work on the LHC.
Sourcing helium for research
Helium is the second-most abundant element in the Universe, but on Earth, it is rare: The atmosphere cannot hold back the light noble gas atoms – ionised helium is transported along magnetic field lines into the upper atmosphere, where its thermal velocity exceeds the escape velocity of 11.2 km/s.
Thus, the constant helium content of about 5 parts per million in the atmosphere is maintained only because helium is constantly being produced anew in radioactive decay: for each uranium, thorium or radon nucleus undergoing alpha decay in the Earth’s crust, a new helium atom has emerged.
This helium gas accumulates in gas fields within Earth, often together with natural gas. That’s where helium can be won. Fortunately for future particle accelerators, and all other applications of helium in science and technology, helium can also be won back from the atmosphere, albeit at a higher cost.