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- Brown, Andrew S., et al.
(författare)
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Sampling of gaseous sulfur-containing compounds at low concentrations with a review of best-practice methods for biogas and natural gas applications
- 2015
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Ingår i: TrAC. Trends in analytical chemistry. - : Elsevier BV. - 0165-9936 .- 1879-3142. ; 64, s. 42-52
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Tidskriftsartikel (refereegranskat)abstract
- The accurate quantification of low-concentration sulfur-containing compounds is essential for the biogas and natural gas industries. We review literature data for the stability of these compounds in standard gas mixtures when sampled in cylinders with different passivations, sample bags, sorbent tubes, solid-phase microextraction and glass sampling bulbs, and we present new data obtained at our three National Measurement Institutes. We show that losses of sulfur-containing compounds are minimized when using passivated sampling cylinders, and the most suitable sorbent material for sampling these compounds is Tenax TA. We also discuss methods for transferring gas from sample vessels to analyzers and give recommendations for the selection of regulators (and other pressure-reducing devices) and transfer lines. Further, we propose approaches that could be taken to reduce or correct for losses in order to provide more accurate measurements of sulfur-containing compounds.
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2. |
- Van Der Veen, Adriaan M. H., et al.
(författare)
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Measurement requirements for biogas specifications
- 2015
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Ingår i: 17th International Congress of Metrology. - Les Ulis, France : EDP Sciences.
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Konferensbidrag (refereegranskat)abstract
- The increased use of biogas and biomethane urgently requires that these non-conventional energy gases can be transmitted through natural gas grids and refuelling stations. The European Standardization Organisation CEN is developing specifications for green gas which supplement the specifications for natural gas. The specifications for green gas address a range of parameters not commonly covered in natural gas, such as the contents of impurities (e.g., siloxanes, ammonia, halogenated hydrocarbons, and hydrogen chloride), dust content and particles. In a collaboration between 12 European metrology institutes and 3 university groups, robust and reliable methods are developed to support these draft specifications and to enable conformity assessment. The project also deals with issues related to density, calorific value, moisture content, and the sampling of biogas. This paper gives an overview of the state-ofthe-art in green gas testing, as well as an outlook what methods need be developed.
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