The lime industry is and will continue to be energy intensive. While certain physical and chemical restrictions limit what level of improvement is theoretically possible to achieve, Nordkalk continues to actively work on issues relating to energy efficiency and climate impact. Measures to optimise our production processes, mix of fuels used or choice of environmental friendly transports are key tools to reduce emissions from our operations. To capture and reuse secondary heat from our limekilns and find solutions to store energy with lime are other efforts to improve climate impact.
Producing quicklime will always require a lot of energy due to the exothermic nature of the process and CO2 will be released from the limestone during calcination due to the chemical reaction formula. Still, we see possibilities to continuously improve our performance both when it comes to energy efficiency and emissions.
In Finland, Nordkalk has a long history of participating in the Energy Efficiency Agreements and is currently participating in the latest agreement which covers the years 2017-2025.
Nordkalk also has a long experience of capturing secondary heat from our lime kilns and using it either on-site or delivering it to the local communities’ district heating networks. All rotary kilns in Nordkalk are equipped with heat recovery set-ups.
During recent years, Nordkalk has decreased emissions into the air by investing in new abatement technology at many of its production plants. The new equipment helps to cut down on both gaseous and particulate emissions. All Nordkalk lime kilns are covered by the EU Emission Trading System, which ensures that the CO2emissions are followed rigorously.
Energy efficiency actions
More than 30 separate energy efficiency improvements were reported during 2018. The projects cover a wide array of improvement actions, such as the optimisation of grinding processes, replacement of motors, pumps, lights and other equipment with more energy efficient versions, improved production, transport and maintenance routines etc.
Energy efficiency 2016-2018
Increased use of biofuels
Last year, Nordkalk’s plant in Ignaberga changed its production to 100% use of biofuels, by using sidestreams from the feed production.
In Vampula, Finland we have been using locally produced biogas since 2011. The biogas is supplied to the plant by a 1,5 km long pipeline, so in addition to decreasing the fossil CO2 emissions from the plant, the amount of transports is also reduced.
At the end of 2018, a biofuel test programme was started in Köping, Sweden. The programme aims to decrease the use of fossil fuels in quicklime production. In 2018, the first full-scale tests were carried out and the project will continue in 2019.
Site example: Improvements in Köping 2018
Nordkalk has also made several other improvements at its production plant in Köping during 2018. The heat recovery setup has been updated, which allows for more secondary heat to be captured. This increase the amount of district heat that can be delivered to the community. In 2018, Nordkalk delivered 40 GWh of district heat to the local community in Köping and Arboga.
The kiln automation system received an update as the function of the kiln optimiser software was improved. The optimiser maximises the energy efficiency of day to day kiln operations.
At Ignaberga, an increase in production rate enabled us to optimise the customer delivery network. Having less demand for supportive deliveries from alternative Nordkalk sites to Southern Sweden we could greatly reduce the overall transportation distances to our customers. The Ignaberga production process was improved using the Lean Six Sigma methodology. Limiting factors in the production chain were identified, ranked and purposely addressed.
Energy storage with lime
In 2018, Nordkalk embarked on an interesting project to study how energy could be stored with the help of lime. The energy storage company SaltX Technology and Nordkalk Corporation signed a Letter of Intent to manufacture Nano Coated Salt.
Especially energy storage from renewable resources is challenging and new technologies are desperately needed. New NCS-technology is one of the solutions. Nano-coated technology by SaltX has been developed to store energy thermo-chemically. The main ingredient of the "salt" is calcium oxide i.e. lime, which has a good volumetric energy density. The technology enables a long-term and a cost-effective solution.
Nordkalk started pilot production in Pargas Finland and has produced several tons of the SaltX NCS based on SaltX’s recipe and specifications. The capacity of full-scale production will be 10,000 tons of NCS, which is equivalent to 4,000 MWh of thermal energy storage.
At Nordkalk, we find it important to support and participate in different development projects to find new ways of doing things that benefit the environment.
- To lowering emissions to air by improving our energy efficiency
and monitoring our completed energy efficiency actions
against the annual target.
- To reporting our CO2 emission performance and aiming to con-tinuously reduce emissions per tonnes of quicklime.
- To investing a minimum of 10% of our investment budget (3-year rolling average) into better environmental technologies and to increasing the automated monitoring of the emissions.
- To choosing low-emission alterna-tives for logistics – transports by sea or rail when possible. Aiming
at a higher payload and alternative fuels in truck transports.
Nordkalk is the leading limestone company in Northern Europe. We deliver essential raw materials to numerous industries, and our solutions contribute to clean air and water as well as productivity of agricultural land.