Full-scale phosphorus recovery from digested wastewater sludge in Belgium - part II: economic opportunities and risks

Water Sci Technol. 2015;71(4):495-502. doi: 10.2166/wst.2014.509.

Abstract

One of the options to recycle phosphorus (P) in the wastewater sector is to recover it as struvite crystals from digested sludge. Measurements on a full-scale demonstration plant in Leuven, Belgium, yielded a first indication of the profitability of struvite recovery, in function of different variables such as incoming PO(4)(3-) concentration, MgCl₂dosing, improved dewaterability, etc. An uncertainty and sensitivity analysis was carried out. Although possible improvement in sludge dewaterability when recovering struvite from digested sludge has a positive economic amortization effect, it is at the same time the largest source of financial risk. A theoretical exercise showed that for struvite recovery from centrate, uncertainty would be lower, and the largest sensitivity would be attributed to ingoing PO(4)(3-) concentration. Although struvite recovery from digested sludge is riskier, it is an investment with potentially a higher return than investment in struvite recovery from centrate. The article provides information for possible financial incentive schemes to support P-recovery.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Belgium
  • Bioreactors
  • Phosphorus / chemistry*
  • Sewage / chemistry*
  • Waste Disposal, Fluid / economics*
  • Waste Disposal, Fluid / methods
  • Wastewater / chemistry*
  • Water Pollutants, Chemical / chemistry
  • Water Purification / economics*
  • Water Purification / methods

Substances

  • Sewage
  • Waste Water
  • Water Pollutants, Chemical
  • Phosphorus