Eggshell: a potential raw material for CEramic wall tiles

PROJECT DESCRIPTION

BACKGROUND

Waste management is one of the most important issues for food processors. More specifically, the egg transformation industry generates large amounts of eggshell waste (about 11% of total egg weight), totalling up to 150 000 t/y in Europe. The consumption of processed egg products currently accounts for 30% of the production of eggs, with increasing demand in the fields of ready-prepared meals, cake mixes, and fast-food. Therefore, the generation of eggshell waste will increase in the coming years. Regulation EC No 1069/2009 considers eggshells as animal by-products not intended for human consumption, establishing strict health rules for their use. For this reason, there is not an extended use of eggshell at industrial scale except for the occasional use as fertiliser or soil conditioner. The most common practice is disposal in landfills. In Europe, more than 90% of this solid waste is disposed inlandfills.

Eggshells are comprised of a network of protein fibres associated with crystalline calcium carbonate (95%), magnesium carbonate (1%), calcium phosphate (1%) and water. Once the membrane of protein fibres is separated, eggshell can become an alternative source of calcium carbonate (bio-CaCO3). Large amounts of calcium carbonate are used in the manufacturing of ceramic tiles. Therefore, eggshell can be a valuable bio-based raw material for the ceramic tile industry. This would help to reduce the impact of the consumption of limestone, a non-renewable natural source of calcium carbonate. Wall tiles contain between 10-15% of calcium carbonate, with an estimated consumption of 300 000 t/y in Europe. Thus the ceramic industry could absorb the totality of the eggshell produced by the egg transformation industry, reducing the extraction of limestone for the ceramic industry by up to 40%.

OBJECTIVES

The main objective of the LIFE EggshellenCE project is to demonstrate the feasibility of using eggshell as a secondary raw material in the production of ceramic wall tiles. The success of the project will lead to environmental and economic benefits for both the egg transformation industry and for the ceramic industry. This will bean example of a circular business model, in line with the European priorities for resource efficiency and with the Waste Framework Directive. Furthermore, the project fully falls within the scope of the recent EU Farm to Fork Strategy regarding new opportunities for stimulating sustainable food processing and reducing food waste.

RESULTS

Expected results:

One prototype for the separation of the egg membrane from the eggshell validated;

Ceramic tiles with between 5 and 12% content of calcium carbonate from eggshell (considering that between 50 and 75% of their calcium carbonate is replaced by bio-CaCO3);

Reduction of at least 90% of egg-related waste generated by the company AGOTZAINA. This entails the valorisation of around 50 t of eggshell during the project, and at least 2500t/y after the project. The consumption of mineral calcium carbonate will be reduced correspondingly;

Start of replication of the solution in at least one other egg transformation company during the project, with expected replication after the end of the project in several Spanish and Portuguese companies in the egg processing and ceramics sectors; and

Development of at least two business models for egg transformation and ceramic tile companies.