PROJECT DESCRIPTION
BACKGROUND
Calcium carbonate (CaCO3) is one of the most widely used minerals worldwide, with a wide range of industrial applications. CaCO3 is a mineral commonly found in rocks such as chalk, limestone and marble. In Europe alone, 53 million tonnes of CaCO3 are mined annually. The open pitch mining destroys landscapes and threatens biodiversity, and CaCO3 mining and the subsequent production of ground calcium carbonate (GCC) is a highly unsustainable and energy-intensive process. The GCC focussed on in this project has an average environmental footprint of 200 kilograms (kg) of carbon dioxide (CO2) equivalent per tonne.
The paper industry is one of the largest consumers of CaCO3, where it is used as filler and a coating pigment. It makes up some 25% of the total CaCO3 consumption. The EU paper industry produces 9 million tonnes of paper sludge annually. This waste stream contains important amounts of CaCO3 and is mostly landfilled or incinerated. This contributes further to the CO2 footprint via the transport of paper sludge for elimination and the release of the captured CO2 in the atmosphere when being incinerated.
In 2014, the company Alucha started the development of a new production process to recover CaCO3 and pyrolysis oil from paper sludge through pyrolysis. Between 2014 to 2018, a small-scale pilot plant (Mine1) capable of converting paper sludge into circular calcium carbonate (CCC) and pyrolysis oil was successfully tested. Mine1 has the capacity to convert up to 100kg per hour into paper sludge, from which 60kg per hour of CCC is produced. Several companies have approved CCC for use in paint, coatings and plastics.
OBJECTIVES
LIFE RE&UCE will demonstrate the recovery of CCC and renewable energy – pyrolysis oil – from paper mill sludge on a large scale.
The project will develop a demonstration plant which is a 15-times scale-up of the existing Mine1 pilot plant. The demonstration plant will be built on the premises of Alucha in Cuijk, in the Netherlands, which is located next to the Essity-owned paper mill.
The demonstration plant will convert paper sludge into CCC, pyrolysis oil and gas. The pyrolysis oil will be reused at the paper mill, and the pyrolysis gas will be used in the pyrolysis process itself. This will lead to an improved environmental performance through:
- converting waste into a valuable resource instead of resorting to incineration or landfill
- energy recovery thanks to the pyrolysis oil
- less mining and consequently less landscape degradation in the EU
- less transport of mined GCC and paper sludge waste in the EU
One production line will be implemented and tested during the LIFE project, with a production capacity of 900kg per hour of CCC, treating 19 700 tonnes of paper sludge per year. The aim is to go from technology readiness level (TRL) 7 to TRL8.
RESULTS
The demonstration plant will have the following expected results:
- 19 700 tonnes per year less paper sludge waste at Essity’s paper mill in Cuijk
- 7 000 tonnes of CCC recovered annually
- 2 000 tonnes a year of pyrolysis oil produced
- 5 230 megawatt hour (MWh) less energy usage from fossil fuels at Essity Cuijk
- 4.3 million kg per year reduction in CO2 emissions
Once the LIFE project is complete, the plan is to implement a second production line (Mine2.2). In the long-term, a third line is planned.
Replication at other paper mills in Europe is foreseen, and four feasibility studies will be conducted during the LIFE project. To achieve this, paper sludge from four paper mills will be processed at the demonstration plant, and the CCC produced will be assessed via dedicated application tests. Four new value chains (VC) for the use of CCC in different industries will be established in the plastics, adhesives and sealants, paints and coatings, and rubber industries.