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Projects: Projects for Investigator
Reference Number NIA_SGN0165
Title HyTechnical – Literature, science review and subsequent revision technical standards for hydrogen pipelines
Status Completed
Energy Categories Hydrogen and Fuel Cells(Hydrogen, Hydrogen transport and distribution) 100%;
Research Types Applied Research and Development 100%
Science and Technology Fields ENGINEERING AND TECHNOLOGY (Mechanical, Aeronautical and Manufacturing Engineering) 100%
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Project Contact
No email address given
Award Type Network Innovation Allowance
Funding Source Ofgem
Start Date 01 June 2020
End Date 01 March 2021
Duration ENA months
Total Grant Value £826,929
Industrial Sectors Energy
Region South East
Programme Network Innovation Allowance
Investigators Principal Investigator Project Contact , SGN (99.997%)
  Other Investigator Project Contact , Wales and West Utilities (0.001%)
Project Contact , Northern Gas Networks (0.001%)
Project Contact , Cadent Gas (0.001%)
Project Contact , SGN (99.997%)
  Industrial Collaborator Project Contact , SGN (0.000%)
Web Site https://smarter.energynetworks.org/projects/NIA_SGN0165
Objectives There are 3 parallel workstreams to complete the work; the desktop exercises for the research work packages, the repurposing standards, hazardous area classification.Workstream 1 Desktop ExercisesPRI Work Package The scope of work for the investigation of, and justification for, additional work required to develop the procedures and specifications which will be required by GDNs and NGGT for the repurposing of the LTS/NTS and its future operation for H2 service required will involve:Literature Review and Industry Visits: Review current code requirements specified in pressure reduction and installation PRI standards compliance with PSR and PSSR to repurpose existing PRI. Literature review to identify the key requirements for the operations inspection, maintenance identified in existing published and authoritative research to determine approach applied to existing H2 installations can be applied to existing installations. Contact equipment manufacturers to understand their experience in designing and manufacturing hydrogen pressure reduction equipment to support the design of new installations and repurposing of existing PRIs Arrange research visits to existing hydrogen facilities in UK and Europe to identify learning which can be applied to design and repurposing of network PRIs. Venting/Hazardous Areas:Review Energy Institute EI Model code of safe practice Part 15: Area classification for installations handling flammable fluids Annex B to determine if additional experimental studies are required to evaluate the venting / hazardous areas. Pressure ranges from 2 to 50 bar relief sizes 10mm, 15mm 32mm, 50mm, 100mm. Gas composition 100% H2 and mixtures of H2/Natural Gas with 20% to 50% H2. IMR Work PackageThe scope of work for the investigation of, and justification for, additional work required to develop the procedures and specifications which will be required by GDNs and NGGT for the repurposing of the LTS and its future operation for H2 service required will involve:Review current code requirements specified in pipeline standards and required for compliance with PSR and PSSR. To include routine and non routine IMR activities. Brief literature review to identify the key requirements for inspection, maintenance and repair identified in existing published and authoritative research i) carried out for the networks, ii) published and iii) included in standards for pipelines transporting H2 and NG/H2 mixtures.Identify the procedure and specification requirements to address the key damage mechanisms and parameters affecting the requirements for damage identification, sizing and assessment for the operation of H2 and H2/NG mixture pipelines, including reduction of ductility and toughness (embrittlement), fatigue crack growth, denting/gouging and metal lossUsing P11 as a roadmap to assess if there are any major changes in inspecting / repairing H2 and NG/H2 pipelines.Output will be documented as P11 impact assessment which will detail for each document subsection: no change / editorial / minor technical / major technical.(a) Review current / emerging in line inspection capabilities for H2 and NG/H2 pipelines to cover: Current tool accuracy, repeatability, POD and feature detectability limitations. Ability of existing technologies to be extended for H2 and NG/H2 pipelines and any limitations (flow / diameter / feature type (especially crack detection in gas pipelines etc.) Emerging technologies that are under development and their suitability forH2 and NG/H2 pipelines – tool (material) compatibility, flowrate (b) ILI interval assessment – assess the methodology required for assessing time dependent failure mechanisms for H2 and NG/H2 pipelines, e.g. corrosion + crack growth, etc.Review and assess the currently available repair methods for application to H2 and NG/ H2 pipelines, including epoxy shells, composite repairs and Plidco clamps. Include assessment of hot work on pipeline steels exposed to hydrogen, and review current capability for carrying out hot tap, stopple and bypass operations on hydrogen pipelines.Consider the expected performance of pipeline girth welds which to not meet current girth weld quality standards (i.e. girth welds on P18 pipelines)QRA Work PackageFurther work is required on understand building proximity distance (BPD) and the minimum separation distance between parallel pipeline (hydrogen vs hydrogen and hydrogen vs natural gas). This first phase is a desktop exercise. Impact assessment of hydrogen transmission on TD/1 BPDs Gather background information on the basis of the existing TD/1 BPDs Perform an assessment of the individual elements of the calculations (gas outflow, fire size and radiative properties, thermal effects) to propose how to adapt them using existing knowledge to estimate new BPDs for hydrogen transmission pipelines, based on fire effects. Calculate new BPDs for hydrogen pipelines for fire effects, following the same principles and assumptions as the existing relationships for natural gas. Perform scoping calculations for delayed ignition, using the estimated inventory of hydrogen within the (unconfined) flammable cloud resulting from a hydrogen release and predicting the possible overpressures that could result. Use existing data for delayed ignition of large scale jet releases as a sense check on the predictions. Compare results of overpressure estimates with predicted BPDs to identify whether overpressures from delayed ignition could extend the hazard ranges beyond the predicted BPDs for fires. Report on impact assessment on BPDs with discussion of significance of overpressure effects for hydrogen and recommendations for further development required for hydrogen pipeline risk assessments. N.B. The scope of work does not include (at this stage) the calculation of risk, which would require inputs on failure frequencies and assumptions of ignition probabilities and ignition timing (especially if overpressure effects are significant). The methodology can be extended to include that in due course as the work on failure frequencies progresses. Ignition will remain an area of uncertainty and hydrogen risk predictions will be cautious until there is more operational experience.Impact assessment on TD/1 parallel pipeline separation distancesTo assess the impact of hydrogen transmission on the recommended separation distances, the possibility of one pipeline transporting natural gas and the other transporting hydrogen may need to be considered, as well as both pipelines transporting hydrogen.The following steps are envisaged, to assess the impact of hydrogen transmission on parallel pipeline separation distances, drawing on existing knowledge only: Estimate the ground pressure loading predicted from a hydrogen pipeline rupture. Consider the ground pressure effect on a parallel natural gas or hydrogen pipeline. Evaluate available ground crater formation models and assess if existing natural gas model is cautious for hydrogen. Considereffects of thermal loading due to hydrogen fires where recommended natural gas separation distances are not met. Check whether puncture releases can be neglected when considering separation distances for hydrogen pipelines (as for natural gas). Report on impact assessment of the use of existing recommended minimum separations for hydrogen transmission pipelines with discussion of the implications where recommended distances cannot be met. To include recommendations for any further work to provide evidence as required. Workstream 2 Transmission and DistributionIGEM will appoint specialist Engineering Contractors to undertake research required to create the new requirements for IGEM standards;The project will start with TD/1 and TD/13 (above 7 bar) first, followed by TD/3, TD/4 and TD/13 (below 7 bar).The methodology for the development of the new requirement of the IGEM standards TD/1, TD/3, TD/4 and TD/13 is detailed below and identifies key steps that will be undertaken during development, which would be challenged and reviewed in parallel to the supplementary documents being produced. 1) Risk Registera. Creation of a risk register identifying additions / updated risks associated with transporting a new fluid (including different pressure tiers, operating conditions and materials) 2) Research Review a. Review relevant research reports and publications to identify how the influence of the change in product can be assessed in terms of: Impact on material properties, applied loading (static / dynamic) and damage / deterioration mechanisms and the consequential change in safety factor and failure frequency Behaviour of the product in planned and unplanned releases Changes to operations, inspection and maintenance requirements. identify any gaps and their impact [priority
Abstract move to decarbonisation in the UK has generated major interest in initiatives into the use of existing natural gas networks (pipelines and installations) for the transportation and distribution of hydrogen (H2) and natural gas/H2 mixtures. The SGN Future of the LTS Phase 1 project identified the potential to repurpose the LTS network. In February 2020 SGN held an industry workshop with attendees from the GDNs, NGGT, HSE, BEIS and industry experts. The aim of the workshop was to share and disseminate the knowledge from the first phase of the project, identify gaps and develop a roadmap for the future. The main outcome from the workshop was to develop a common framework of needs to allow the projects to be developed to complete the gaps. Following the workshop, we established IGEM LTS Futures group. This group will ensure the research undertaken underpins the national standards and supports hydrogen implementation. All the GDNs and NGGT are members of IGEM LTS Futures, which SGN chairs, and the work will be done collaboratively. Following on from the Future of the LTS Phase 1 project, there is a requirement to undertake; material testing and analysis, desktop exercises to understand the impact hydrogen has on, (i) inspection, maintenance and repair (IMR) and (ii) repurposing pressure reduction installations (PRI) and closing gaps in the Quantified Risk Assessment (QRA). The desktop exercise to understand the impact hydrogen has on IMR, PRI and QRA will be done in parallel of writing the standards to provide input to the standards and further guidance to the GDNs and NGGT. The development of approved industry standards to formalise requirements and secure safe best practise is needed to ensure consistency in repurposing existing natural gas networks, construction of new assets, and to ensure compliance with legislation. The GB gas industry are driving forward towards live consumer trials in the medium terms. As such it is imperative that the GB industry have a suit of supportive standards that deliver consistency and confidence in the engineering practise deployed for such trial activity and future expansion of hydrogen for heat. This is therefore a high priority. Current projects which will benefit from the availability of approved standards include, the SGN Future of the LTS and H100 projects, the Cadent HyNet project which includes development in the WWU network, H21 and the National Grid HyNTS. The standards which apply to the existing natural gas networks have been developed over many decades and are widely regarded having overseen significant improvements in asset delivery and management resulting in exemplary level of safety and reliability. These standards are published and managed by the Institution of Gas Engineers and Managers (IGEM). Following on from the Future of the LTS Phase 1 project, there is a requirement to undertake an urgent literature-based research for the development of new supplements/documents to these IGEM current natural gas standards which will enable the repurposing of the existing assets and the design and construction of new assets for H2 and Natural Gas/H2 mixtures. The research and the creation of new supplements/documents can be prepared, approved and published more quickly than developing new standards and can be incorporated into the existing standards when they are next reviewed. This NIA is directly focused on the future low carbon solutions for the gas industry which will support the governmentstarget of Net Zero by 2050 by creating technical standards which allow real engineering to be developed. This work is essential to provide, secure and sustainable long term customer benefits.
Publications (none)
Final Report (none)
Added to Database 02/11/22