Firstgas Group (FGL) owns and operates New Zealand’s high pressure gas transmission system and gas distribution networks that supply more than 60,000 North Island businesses and homes.
Ecogas have built NZ’s first large scale anaerobic digestion plant at Broadlands, Reporoa.
Verbrec NZ have been engaged by First Renewables, part of the First Gas group, to design the balance of plant for the upgrading of the biogas produced by Ecogas, which includes safely injecting it into the existing gas pipeline system.
METHODOLOGY
For the biogas to be safely introduced into the pipeline, it is required to be upgraded to high quality biomethane at the Reporoa plant, and certain sections of the pipeline need to be adjusted to operate at a lower pressure.
Verbrec has been engaged to deliver the following:
- FEED for the Biogas Upgrading Facility
- DD for the Biogas Facility
- DD for 3 x delivery points (Broadlands, Taupo and Reporoa)
- DD for the pipeline to link the Biogas Facility to the gas network
SOLUTION
Gas Conditioning: before injecting biogas into the pipeline, it needs to be cleaned and conditioned to meet the quality standards of the natural gas grid.
Biogas is typically produced at a relatively low pressure, so it needs to be compressed to be able to be injected into the natural gas pipeline system.
To meet the national gas specification, biogas needs to undergo additional treatment to remove carbon dioxide and other trace components, resulting in a higher methane content.
Once the biogas has been cleaned, conditioned, and compressed, the biomethane is injected into the natural gas pipeline system. The injection point is usually located near the biogas production facility or at a suitable connection point along the pipeline route.
BENEFITS
The injected biomethane can replace conventional natural gas in sections of the pipeline, and is transported and distributed to consumers like residential, commercial and industrial users.
Biomethane contributes to the overall gas supply and reduces the reliance on fossil fuel-derived natural gas.