The glass industry is also facing the challenge of finding alternative energy sources to natural gas. In a joint project, the Bundesverband Glasindustrie e.V. and the Gas- und Wärme-Institut Essen have investigated hydrogen as a possible source of energy and have now successfully completed the project.
The Bundesverband Glasindustrie e.V. (BV Glas) and the Gas- und Wärme-Institut Essen e.V. (GWI) have successfully completed their joint HyGlass project. The aim was to investigate Hydrogen in regenerative glass melting tanks, to replace natural gas as an energy source in the long term. Both hydrogen-natural gas mixtures and the use of pure hydrogen were investigated.
The HyGlass project was funded by the Ministry of Economic Affairs, Innovation, Digitalisation and Energy of the state of North Rhine-Westphalia via the „progres.nrw - Innovation“ funding programme with the support of NRW.Energy4Climate and was supported with great commitment by glass manufacturers in North Rhine-Westphalia. In addition to the use of hydrogen in the glass melting process, the GWI experts also analysed the Aspects of logistics and procurement as well as technical feasibility along the value chain. The focus was on analysing the effects of hydrogen on both combustion and glass quality.
„Hydrogen is one of the great hopes for the switch from conventional to renewable energy sources. BV Glas therefore started looking at the potential early on as part of its decarbonisation strategy.“
Dr Johann Overath, Managing Director of the Bundesverband Glasindustrie e.V.
The experiments and simulations have shown that the use of hydrogen has a moderate overall effect on combustion as long as the air flow rate and burner output are kept constant using a control strategy. Both furnace chamber temperature and heat transfer remain almost constant. The use of hydrogen can result in higher NOx emissions, but these can be compensated for by technical measures on the furnaces.
One The challenge, on the other hand, is to minimise the influence of hydrogen on glass quality.
„We have found that the use of hydrogen in the glass melt can indirectly lead to changes in glass quality, e.g. discolouration. Interestingly, these discolourations are independent of the hydrogen content in the natural gas-H2 mixture and therefore cannot be regulated by higher or lower admixture rates,“ explains Dr Anne Giese, Head of the Industrial and Combustion Technology Department at GWI. However, an adjustment could be made via a Changed composition of the glass batch be carried out. Further comprehensive tests are required here in order to achieve the desired glass quality in the long term.
For the glass industry to be able to switch to hydrogen in the long term, the Availability of green electricity significantly increased be realised. The investigations have also shown that the available electricity generation capacities (wind and solar) within a radius of 20 kilometres of the respective glass locations in NRW are currently not sufficient to produce hydrogen, even if these were only available for the glass industry.
Source: Bundesverband Glasindustrie e.V.