Effect of nano-ZnO on biogas generation from simulated landfills

Waste Manag. 2017 May:63:18-26. doi: 10.1016/j.wasman.2017.01.017. Epub 2017 Jan 23.

Abstract

Extensive use of nanomaterials in commercial consumer products and industrial applications eventually leads to their release to the waste streams and the environment. Nano-ZnO is one of the most widely-used nanomaterials (NMs) due to its unique properties. It is also known to impact biological processes adversely. In this study, the effect of nano-ZnO on biogas generation from sanitary landfills was investigated. Two conventional and two bioreactor landfills were operated using real MSW samples at mesophilic temperature (35°C) for a period of about 1year. 100mg nano-ZnO/kg of dry waste was added to the simulated landfill reactors. Daily gas production, gas composition and leachate Zn concentrations were regularly monitored. A model describing the fate of the nano-ZnO was also developed. The results obtained indicated that as much as 99% of the nano-ZnO was retained within the waste matrix for both reactor operation modes. Waste stabilization was faster in simulated landfill bioreactors with and without the addition of nano-ZnO. Moreover, the presence of the nano-ZnO within the waste led to a decrease in biogas production of about 15%, suggesting that the nano-ZnO might have some inhibitory effects on waste stabilization. This reduction can have potentially significant implications on waste stabilization and the use of biogas from landfills as a renewable energy source.

Keywords: Anaerobic digestion; Biogas; Bioreactor landfills; Nano-ZnO; Nanoparticle; Sanitary landfills.

MeSH terms

  • Air Pollutants / analysis*
  • Air Pollutants / chemistry
  • Air Pollution / prevention & control
  • Air Pollution / statistics & numerical data
  • Biodegradation, Environmental
  • Refuse Disposal / methods*
  • Waste Disposal Facilities*
  • Zinc Oxide / analysis*
  • Zinc Oxide / chemistry

Substances

  • Air Pollutants
  • Zinc Oxide