REFLOW Overall Research Goals:

  • To develop and demonstrate processes for the recovery and reuse of phosphorous (P) products from DPW;
  • To establish their fertilizer value and optimum application rates through laboratory protocols and field trials;
  • To address the environmental, social, food safety and economical challenges, ultimately finding market-driven solutions for the new processes and fertilizer products.

The REFLOW research-training programme comprises five integrated cohesive and complementary work packages (WP). REFLOW will have significant societal impact through closing the phosphorous loop for the dairy industry by delivering cost effective P recycling processes which minimise leakage, producing safe, effective high value fertiliser products.  Its socio-economic impact will be facilitated by the strong industry presence driving WPs 1-3.).

REFLOW specific scientific and technological objectives:

  • To achieve removal of up to 90% of soluble P from dairy effluent streams using enhanced biological P removal rather than chemically with alum or iron salts, to concentrate it P-rich bio-solids (WP1).
  • To release P from P-rich bio-solids as a sterile substrate by using fluidised bed incineration (<850oC) thermochemical processes combined with energy recovery (WP1).
  • To extract and recover heavy-metal-free, water-soluble phosphate salts or phosphoric acid, to create new REFLOW fertilizers (WP1).
  • To assess the effect of the REFLOW fertilizers on crop yield for forage crops (grass, maize) and soil health (WP2).
  • To determine how the new fertilizers affect greenhouse gas (GHG) emissions and N dynamics, by conducting comparative field trials with conventional fertilizer from rock phosphorous (WP2).
  • To map the loss of P through investigating P-dynamics over time in the run-off pathway, and post-application of DPW and new fertilizers to agricultural land (WP2).
  • To develop sustainability indicators and conduct a comprehensive life-cycle analysis (LCA) of REFLOW fertilizers to determine carbon footprint relative to commercial fertilizers (WP3).
  • To develop guidelines and an application tool to assist farmers and growers in determining optimised applications rates of REFLOW fertilizers based on their Fertilizer Equivalence Value (FEV) (WP3).
  • To develop an interactive Financial Model for REFLOW products which will consider investment and operating costs for each of the REFLOW products, including processing costs, regulatory, compliance, and market activation instruments, and to assess the impact of market dynamics on the future commercial uptake of REFLOW fertilizers (WP3).
  • To identify any potential risk to food safety as a result of the application of dairy processing sludge and the REFLOW fertilizer products (WP3).