PROJECT DESCRIPTION
BACKGROUND
Whey permeate (WP) is a by-product of the dairy industry, obtained during cheese production. A typical cheese WP consists mainly of water, approximately 4-5% of lactose, nitrogenous components (0.9%), minerals and traces of vitamins. The presence of lactose and proteins represents a potential source of re-usable substances, but which are not properly valorised, and whose disposal generates adverse consequences for the environment. According to the European Dairy Association, the EU produces around 10 M tons/year of cheese (EDA, 2018), which corresponds to 4 M tons/year of WP.
Currently, a significant amount of WP is pumped untreated into rivers and water bodies, scattered on the soil, or given in an unprocessed form as animal feed and sold for little or no profit to farmers. WP is an important pollutant, demonstrating between 35-50 g/l Biochemical Oxygen Demand (BOD) and around 60-80 g/l Chemical Oxygen Demand (COD). A significant amount of WP is currently used for farmland irrigation, but its use as a soil fertiliser is limited to about 45-90 tons/acre without damage to watercourses, crop yield, and soil structure. Whilst technologies are now available for whey permeate treatment, the current focus of dairy companies is typically on facilities for cheese and whey protein production, with limited investment in developing innovative biorefining processes and facilities to manage WP.
OBJECTIVES
Whey2LIFE aims at addressing the environmental impacts of cheese production by overcoming the main barrier currently limiting the appropriate valorisation of whey permeate (WP). This barrier is the lack of investment by dairy companies to address WP valorisation and the absence of a proven economically-affordable process for whey permeate reuse that makes it worth extending its value chain.
The specific objectives are to:
enable industrial symbiosis by upgrading the existing anaerobic digester (AD) facility towards an integrated biorefinery (10-14 kton/year of fermentation capacity) that enables the extension of the WP value chain in a cost-effective way, maximising the recycling potential of process side-streams (wastewater, digestate, CO2); produce a high-quality protein-rich (40-50% protein yield) biomass as a non-GMO functional ingredient for animal and aquaculture feed manufacturing, able to replace costly soy/potato-based proteins and fish oil; perform quantitative assessment of environmental impact indicators by LCA to prove the economic feasibility and the environmental benefits of the concept; stimulate stakeholders to the valorisation of WP to create a business system, which can unlock the value embedded in under-utilised resources, reducing the economic burden of environmentally-friendly industrial processes; and pave the way for replication and transfer of results in other EU countries. The project contributes to the implementation of the 7th Environment Action Programme, the Roadmap to a Resource-efficient Europe, the Water Framework Directive, the Nitrate Directive and other EU policy relating to the circular economy, waste and water treatment, and energy and resource use efficiency.
The project contributes to the implementation of the 7th Environment Action Programme, the Roadmap to a Resource-efficient Europe, the Water Framework Directive, the Nitrate Directive and other EU policy relating to the circular economy, waste and water treatment, and energy and resource use efficiency.
RESULTS
Expected results: The project aims for 100% valorisation of whey permeate (WP) by using it as a biorefinery feedstock to produce valuable yeast biomass. This can then be used as a protein-rich ingredient for animal feed, in line with circular economy principles, thereby facilitating new methods for disposal of animal-origin products from dairies. The wider benefits anticipated include:
waste management: 10-14 kton/year of WP valorised instead of improper disposal in fields and water bodies; Water: 19 800 m3 of wastewater processed in the anaerobic digester (AD) plant instead of being discharged in public sewage systems; energy from renewables: residues from the biorefinery will contribute to the production of 2.7 MW, corresponding to 1.7 MW of renewable electricity and 1 MW of thermal power generated from the CHP plant, firing the biogas produced in the AD, with the surplus thermal power available for the biorefinery; GHG emissions: contribute to 6 948 kton/year of CO2 savings, equivalent to emissions from more than 1 200 homes electricity use for 1 year; CO2 capture/savings: the CO2 released during the fermentation process will initially be used to enhance biogas production. As the production volume increases, the CO2will be captured and reused in the beverage industry when it exceeds the biogas production capacity of 2 566 kton/year; land use and agriculture: 1 250 ha (corresponding to 1 250 soccer fields) of land could be fertilised with 44 kton digestate generated in the AD. As no nutrients are lost during AD, farmers can close the circular system and reuse the nutrients contained in the digestate; rReduction of fertiliser use: production of c.44 kton/year of digestate to be used in agriculture to replace inorganic fertilisers. According to the European Biogas Association (2017) 1 ton of artificial fertiliser replaced with digestate saves 1 t of oil, 108 t of water and 7 t of CO2 emissions; consumption of resources: AD digestate gives the possibility to recycle phosphate from side-streams. The amount of digestate produced in the project will replace the following quantities of inorganic substances: 52.6 t of phosphorus, 13.1 t of nitrogen and 39.4 t of potassium; and socio-economic benefits:Production of 1.75 -2.25 kton/year (92% dry matter) of yeast biomass with a protein fraction between 45-50% to be used as feed ingredient/biorefinery input; and aWhey2LIFE industrial cluster that is expected to generate 10 FTE jobs.
