title: Reduction of nitrogen loss and Cu and Zn mobility during sludge composting with bamboo charcoal amendment.
abstract: OBJECTIVE
  Composting is an effective treatment process to realize sludge land application. However, nitrogen loss could result in the reduction of nutrient value of the compost products and the stabilization effect of composting on heavy metal concentration and mobility in sludge has been shown to be very limited.
  
  
  METHODS
  Laboratory-scale experiments were carried out to investigate the effects of bamboo charcoal (BC) on nitrogen conservation and mobility of Cu and Zn during sludge composting.
  
  
  RESULTS
  The result indicated that the incorporation of BC into the sludge composting material could significantly reduce nitrogen loss. With 9% BC amendment, total nitrogen loss at the end of composting decreased 64.1% compared with no BC amendment (control treatment). Mobility of Cu and Zn in the sludge may also have been lessened, based on the decline in diethylenetriaminepentaacetic acid-extractable Cu and Zn contents of composted sludge by 44.4% and 19.3%, respectively, compared to metal extractability in the original material.
  
  
  CONCLUSIONS
  Ammonia adsorption capability of BC might be the main reason for the retention of nitrogen in sludge composting materials. Decrease of extractable Cu2+ and Zn2+ in the composting material mainly resulted from the adsorption of both metals by BC.
  
  
  CONCLUSIONS
  Incorporation of BC into composting material could significantly lessen the total nitrogen loss during sludge composting. Mobility of heavy metals in the sludge composting material could also be reduced by the addition of BC.
  
  
  CONCLUSIONS
  Bamboo charcoal could be an effective amendment for nitrogen conservation and heavy metal stabilization in sludge composts. Further research into the effect of BC-amended sludge compost material on soil properties, bioavailability of heavy metals, and nutrient turnover in soil needs to be carried out prior to the application of BC-sludge compost in agriculture.
authors.affiliation: College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310029, China.
authors.forename: Li
authors.initials: L
authors.lastname: Hua
authors.forename: Weixiang
authors.initials: W
authors.lastname: Wu
authors.forename: Yuxue
authors.initials: Y
authors.lastname: Liu
authors.forename: Murray B
authors.initials: MB
authors.lastname: McBride
authors.forename: Yingxu
authors.initials: Y
authors.lastname: Chen