Energy and carbon emissions
Sugar production is an energy-intensive process. Beet expenses aside, energy is our highest cost. We therefore have a long-standing commitment to reduce our energy consumption. We achieve this by continuously improving the effectiveness of the sugar production processes and by investing in new innovative energy-saving projects.
Using energy efficiently
Most of our production factories are equipped with their own efficient power plants. This means our factories produce the steam and electricity required for the sugar manufacturing process and thus lower the amount of electricity we have to buy from the local grid.
The power plants – the boilers - burn fossil fuels (oil, gas or coal) to produce steam, and electricity required for the sugar manufacturing process. The boilers release carbon emissions, as well as air pollutants such as sulphur dioxide (SO2) and nitrogen oxides (NOx). We are taking steps to minimise emissions from our boilers, including substituting fuels for cleaner alternatives where possible. Read more about emissions from Boilers.
We are looking at the possibility of further reducing carbon emission from our boilers by installing bivalent operating systems when existing boilers need to be reconstructed or new boilers are installed. Bivalent operating systems use either natural gas or oil. Natural gas usage emits less CO2 than oil and coal combustion. These systems are already in place in most of our German factories where natural gas is used.
Nakskov Sugar Factory will change fuel from heavy fuel oil and coal to liquefied Natural Gas (LNG) 2021/2022. The change will reduce CO2 emission by app. 28.000 t/year. The rebuild of the boilers also include installation of low NOx-burners.
In recent years we have optimized the biogas production of our anaerobic wastewater treatment plants. The biogas produced there can be burned in the boilers, reducing CO2 emissions by up to 5 per cent in some plants.
Steam dryers
Drying pulp process in Nordzucker production plants is performed by 55% in modern steam dryers.
Energy to a steam dryer is supplied as steam at a pressure of e.g. 16 bar direct from the boilers. The feed steam is returned as a pure condensate and used as feed water in the boilers.
All the energy supplied to the dryer is leaving as steam, and used as energy supply for the first evaporator effect. The steam leaving the dryer is actually the water evaporated from the beet pulp. By using this steam in the first evaporator effect, a full energy recovery is achieved, and air pollution from dust and smell is fully avoided.
In 2012/13, we installed a steam dryer in Nakskov (Denmark). A similar steam dryer has been installed in Örtofta (Sweden) during the sugar production campaign in 2014.
Other energy-saving initiatives
Other examples of recent energy-saving projects include the sixth-effect evaporation station in Säkylä (Finland). Sugar juice is concentrated in a multi-effect evaporator. Water evaporated as steam in the first effect is used for heating the next evaporator effect. The more effects the evaporation process has, the more energy efficient the process is. The sixth-effect in Säkylä has saved us about 5,000 tonnes of CO2 per year.
In Poland, we expanded the evaporation system to include a sixth effect and invested in a new heat exchanger, which together contributed to savings of around 6,000 tonnes of CO2 per year.