Case study: Granville Ecopark // APROVIS
Granville EcoPark is an Enhanced Anaerobic Digestion Facility based outside Dungannon. The state-of-the-art facility is the largest of its kind in Northern Ireland and the company is currently the market leader in Ireland within the sector.
The plant’s process utilises food waste to produce a biogas which is then used to power onsite CHP (Combined Heat and Power) units to generate renewable electricity.
In 2018, the company undertook a project to integrate two APROVIS EGHEs (Exhaust Gas Heat Exchangers) into their system to capture waste exhaust heat being created by two of these CHP units and utilise it elsewhere on site.
Specifically, they sought to use it to heat water needed for their biogas upgrading system, a task previously achieved using an oil boiler. The Upgrading plant, built by PureGas, uses hot water of around 130 degrees to remove CO2 from biogas creating Biomethane which is 99% CH4.
Successful completion represented the potential for substantial savings and a more environmentally sustainable process, central to the company’s ethos.
Due to their track record of successful EGHE projects, APROVIS was selected as the main supplier for the project. The design was completed with collaboration between APROVIS design engineers and the GECO team in April & May 2018 with delivery of the new units in September 2018.
The new EGHEs were connected by fabricating connecting ductwork, maintaining the current CHP silencers. This method once completed and lagged resulted in noise levels around this process area being vastly reduced.
In order to introduce the hot water now being produced via the EGHEs to the Puregas system across the site, 100m of overhead pipeline system was installed. After a successful commissioning, the company’s oil consumption vastly reduced and by mid-way through November the oil boiler had been switched off entirely with all heat requirements being supplied by the CHPs waste exhaust heat.
The success of the project has seen Granville’s oil usage virtually eliminated with the boiler now only being turned on when routine maintenance work of the new system is carried out, representing savings of up to £250,000 a year to the company. Furthermore, Granville now has access to valuable real-time data on the waste heat being produced in their process. This has allowed them to consider options for how unused output their other CHP units could potentially be used in future, further developing and improving their existing circular economy model.