Abstract

The European Union’s circular economy strategy aims to increase the recycling and re-use of products and waste materials. According to the strategy, the use of industry waste materials and side flows is required to be more effective. In this research, a chemical precipitation method to simultaneously remove ammonium and phosphate from the reject water of anaerobic digestion plant using calcined paper mill sludge and fly ash as a precipitant, was tested. Paper mill sludge is a waste material formed in the paper-making process, and fly ash is another waste material formed in the power plant. Objective of this research was to test whether these industrial waste streams could be used as low cost precipitation chemicals for ammonium and phosphate removal from wastewaters and whether the precipitate could be suitable for fertilizer use. Results indicated that calcined paper mill sludge had high removal efficiency for both ammonium (97%) and phosphate (73%). Fly ash also had good removal efficiency for both ammonium nitrogen (74%) and phosphate (59%) at 20 ± 2 °C. The precipitates contained high concentrations of nitrogen and phosphate and could be used as a recycled fertilizer. Other possible mechanisms for the removal of phosphate and ammonium were considered.Graphic

Highlights

  • The European Union’s circular economy strategy aims to increase the recycling and re-use of products and waste materials [1]

  • The particle sizes were distributed at a wider range in calcined paper mill sludge than in fly ash

  • The utilization of industrial waste materials as secondary raw materials is crucial for sustainable new technologies

Read more

Summary

Introduction

The European Union’s circular economy strategy aims to increase the recycling and re-use of products and waste materials [1]. The use of industry waste materials and side flows should be more effective. The first goal of the waste hierarchy is to prevent formation of waste streams. If this is not possible, the step is to prepare waste for re-use, followed by recycling and other recovery (e.g., energy recovery). According to Sokka et al [3] re-use and symbiosis products manufactured from side flows or waste materials in the local industry carry a small environmental load

Methods
Results
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call