ISO 23306:2020 pdf download

ISO 23306:2020 pdf download.Specification of liquefied natural gas as a fuel for marine applications
1 Scope
This document specifies the quality requirements for Liquefied Natural Gas (LNG) used as a fuel for marine applications. It defines the relevant parameters to measure as well as the required values and the test reference methods for all those parameters. This document applies to LNG from any source, e.g. gas from conventional reservoirs, shale gas, coalbed methane, biomethane, synthetic methane. LNG described in this document can come from synthesis process out of fossil fuels or renewable sources. This document identifies the required specifications for fuels delivered at the time and place of custody transfer (at the delivery point).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 6578, Refrigerated hydrocarbon liquids — Static measurement — Calculation procedure
ISO 6974 (all parts), Natural gas — Determination of composition and associated uncertainty by gas chromatography
ISO 6976, Natural gas — Calculation of calorific values, density, relative density and Wobbe indices from composition
ISO 8943, Refrigerated light hydrocarbon fluids — Sampling of liquefied natural gas — Continuous and intermittent methods
EN 16726, Gas infrastructure — Quality of gas — Group H
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1 biomethane
methane rich gas derived from biogas or from gasification of biomass by upgrading with the properties similar to natural gas
[SOURCE: ISO 14532:2014, 2.1.1.15]
5 Sampling
Samples for quality verification are not mandatory but can be taken at various locations as agreed among the parties concerned. Samples, if any, can also be taken at multiple moments in time, as LNG has distinct different ageing characteristics than traditional hydrocarbon maritime fuels (with regards to ageing reference is made to Annex D). In order to ensure a representative sample, proper sampling procedures should be followed. When sampling of LNG for analysis is carried out, it shall be in accordance with the procedures provided in ISO 8943 or an equivalent national standard agreed between the parties concerned. Where specific sampling requirements are documented, the relevant parties should agree on the reference test methods. The LNG collected in liquid state shall be instantly conditioned to gaseous state without any partial vaporization or loss of molecular components to ensure a representative sample. There are two methods for sampling LNG as defined in ISO 8943, continuous and intermittent. Both methods obtain LNG from the LNG cargo/bunker line and then it is gasified in a vaporizer. The continuous method collects the gasified LNG in a sample holder at a constant flow rate for offline analysis. The intermittent method collects gasified LNG and directs it to an on-line analyzer at predetermined intervals. Please refer to ISO 8943 for more details on these methods. The requirements for sampling LNG for marine applications can vary throughout the industry, depending on availability and equipment. Load port samples can be used for quality determination if the sampling equipment is not available and if it is agreed between the parties.